Lead lecture –Biotic stress

Stress on Agriculture Education and Research System

SK Laha*, PM Bhattacharya and A Roy

Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal 736 165., Email: slahaubkv@yahoo.co.in

Present day agriculture in India is full of stress at various levels. The stress related to human factor is perhaps the most important of them. It is observed that in the farming community, the farmers by and large, are ignorant about most of the crop diseases, particularly at initial stage and thus they approach for any suggestion at the fag end when it is too late. Often insect damages are confused with diseases leading to selection of wrong pesticides. There is trend to apply over dose of pesticides which often leads to Phyto-toxicity. The farmers, knowingly or unknowingly, do not care for any waiting period after application of pesticide leading to high residual toxic products in their produce. Moreover, the equipments used for application, the method of application and the safety measures followed are all faulty in most of the cases. Another important factor is the over dependence on chemical methods of disease management. Often they approach the experts and demand for remedies involving application of chemicals. They are not satisfied if some cultural measures are suggested. The recent trend by many farmers has to apply over doses of fertilizers, particularly nitrogen which often makes it impossible to manage a disease by any means. For some diseases (e.g., late blight of potato) community approach is needed. In addition, majority of the farmers are of the habit of getting critical inputs free of cost and loose interest when the critical input is withdrawn even after being satisfied about the effectiveness of the suggested technology.

At the site of education, the teachers often fail to introduce students about disease in population. A few field visits are organized and the curriculum includes mostly laboratory based practical. The present course and curriculum has not been able to build up self confidence in students. The fault lies in not only unwillingness of most of the students to be attentive but also in the quality and way of sharing knowledge from teachers' end. Consequently, the training to students is by no means completed to develop human resources as per farmers' requirement.

In the context of research activities, in our country most of the research stations are not well equipped with many facilities required for field and laboratory work. Region specific problem oriented research programme is comparatively low. Rather execution of programme formulated at hierarchical system is going on. The fund flow in fundamental research has been lowered down during recent past in agricultural sector creating hindrance in finding actual cause in stress biology. The culture and ethics within the working force is also now questionable. Plagiarism in information generation along with predetermined and fabricated

results in research publications may also aggravate the negative impact at field level. It is therefore urgently needed to assess the entire perspective and re-orient the agriculture education research and extension system that will be complementary to farmers' requirement.

Lead lecture-abiotic stress

Alleviation of Salinity and Water Stress in Crop Plants by Osmo-Tolerant Plant Growth Promoting Rhizobacteria

U Chakraborty*, BN Chakraborty, AP Chakraborty and PL Dey

Plant Biochemistry Laboratory and Immuno -Phytopathology Laboratory, Department of Botany, University of North Bengal, Siliguri-734013, West Bengal, Email- chakrabortyusha@hotmail.com

A large number of bacteria were isolated from rhizosphere of different plants viz. Triticum aestium, Cynodon dactylon, Imperata cylindrical and Camellia sinensis. Paenibacillus polymyxa (TRS5), Bacillus megterium (TRS 7) and Ochrobactrum anthropi (TRS 2) obtained from the rhizosphere of tea were found to be highly salt-tolerant, when grown in nutrient broth medium supplemented with 10% NaCl and also exhibited PGPR characteristics. Besides, 9 isolates (S1-5 and N1-4) from rhizosphere of C. dactylon, 27 isolates from wheat rhizosphere (W1-27) and 18 isolates from I. cylindrica (IP1-18) were also found to be salt-tolerant. Those bacterial isolates showing positive responses in vitro were identified by morphological, biochemical and 16SrDNA sequencing to be Ochrobactrum pseudogregnonense (IP8), Bacillus safensis (W10) and Bacillus cereus (S4). Scanning electron microscopic observation and RAPD-PCR analysis of the isolates were done for microscopic and molecular characterization. In vitro PGPR tests such as phosphate solubilization, siderophore production, IAA, chitinase production showed positive results. W5, 10, 11, IP5, 8 and 23 also showed ACC deaminase activities. On the basis of in vitro PGPR tests, eight isolates (Bacillus cereus, B. safensis, O. pseudogregnonense, N2, N4, TRS-2, 5 and 7) were selected as potential salt-tolerant PGPR for field study to determine their ability to promote growth of plants under saline as well as water stress conditions. For in vivo studies on certain crops, Bacillus cereus was applied along with 200ml of 200mM NaCl to the rhizosphere of Vigna radiata, Cicer arietinum and Oryza sativa separately. Results revealed that the bacterium could promote growth, elicit antioxidant responses against salt stress as well as induce the activities of defense enzymes associated with ISR significantly. For salinity studies on wheat, aqueous suspensions of S4, N2, N4, TRS-2, TRS-7 and TRS-5 were applied thrice at an interval of one day to the rhizosphere of wheat plants which were already treated with 200mM NaCl solution. For water stress studies, B. safensis and O. pseudogregnonense which were found to be drought tolerant were selected and these could promote

J Mycol Plant Pathol, Vol. 42, No.4, 2012538

Abstracts of the papers presented at the National Symposium on “Biotic and Abiotic Stresses in Plants under Changing Climate Scenario” at

thEast Zone Meet, UBKV, Pundibari, Coochbehar (WB), 29-30 November, 2012

J Mycol Plant Pathol, Vol. 42, No.4, 2012 539

growth in terms of increase in root and shoot biomass, height of plants, yield, as well as increase in chlorophyll content. Besides, the wheat plants could withstand water stress more efficiently in presence of the bacteria as indicated by delay of appearance of wilting symptoms increases in RWC of treated water stressed plants. In case of both salinity and water stressed conditions, application of bacteria led to elevated antioxidant responses which were evident as elevated activities of enzymes such as catalase, peroxidase, ascorbate peroxidase, superoxide dismutase and glutathione reductase as well as increased accumulation of antioxidants such as carotenoids and ascorbate. Results clearly indicate that the ability of wheat plants to withstand water stress is enhanced by application of these bacteria which also function as plant growth promoting rhizobacteria. Thus, osmo-tolerant PGPR strains could be used in field condition in order to mitigate saline stress in crop plants as they are beneficial and also economically suitable for the cultivars than any other approaches like manipulation of stress associated gene expression and conventional plant breeding.

Invited lecture-biotic stress

Molecular Detection of Viral Diseases from Economically Important Crops and Allied Weeds of North East Indian Plains

*Aniruddha Saha , Bikram Saha, Piyali Sarkar, Prosenjit Chakraborty, Shibu das and Dipanwita

1Saha1Department of Botany, Deparment of Biotechnology, University of

North Bengal, India, Pin 734013. E-mail: asahanbu@yahoo.co.in

The north East Indian states are suitable for cultivation of several horticultural crops. The place is also known for its rich biodiversity. Diseases and pests are major limiting factors for cultivation of horticultural crops. Viral diseases also constitute substantially to limit the production. In the present study, an approach has been taken to detect viral pathogens of major horticultural crops like tomato, potato, papaya and bean and uncultivated plants like datura, jatropha, croton, acalypha and ageratum as a reservoir of viral pathogens. Genome sequencing of most conserved regions have been done for molecular detection of the viruses. Using universal primers, begomoviruses were detected from tomato, potato and uncultivated plants like datura, jatropha, croton, acalypha and ageratum. Four viruses namely Tobacco curly shoot virus (TbCSV), Tomato leaf curl New Delhi virus (ToLCNDV), Tomato leaf curl Bangladesh virus (ToCBV) and Tomato leaf curl Ranchi virus (ToLCRnV) have been provisionally identified from cultivated tomato. Tomato leaf curl New Delhi virus (ToLCNDV) was also provisionally identified from potato and datura plants growing in the region. The above mentioned viruses were not associated with papaya and bean. On the basis of sequencing of PCR amplified viral genome using RT-PCR kit Papaya ring spot virus (PRSV), Potato virus Y (PVY) and Bean common mosaic virus (BCMV) were detected in papaya, potato and bean respectively. Papaya ring spot virus type-P (PRSV-P) was confirmed following host range test. Several botanicals (plant extracts) were tested to control Bemisia tabaci, the vector of begomoviruses present in tomato fields. Out of the botanicals tested two botanicals could check the insect infestation in north East Indian field condition.

Induction of Plant Growth Promotion in Persea bombycina Kost by Bacillus pumilus

1 1* 1A Acharya , BN Chakraborty , U Chakraborty , J 2 2 3Rabha , DK Jha , HK Sharma

1Immouno-Phytopathology Laboratory, Department of Botany, 2University of North Bengal, Microbial Ecology Laboratory,

3Department of Botany, Gauhati University, Department of Biotechnology, Gauhati University. Email: bncnbu@gmail.com

Persea bombycina Kost, family Lauraceae, with the local name “Som” is one of the main primary host plants of muga silkworm (Antheraea assama), and has significant effects on the health and survival of the silkworms. A study was made to improve the health status of Som plant with the application of plant growth promoting rhizobacteria Bacillus pumilus (BRHS/C1) as foliar spray as well as directly applying it to the soil. Eight different varieties of Som plants viz. S1, S2, S3, S4, S5, S6, S7 and S8 were used in this study. An increase in height, number of leaves and branches in all the varieties were observed following the application of the bacterium. Increase in the level of the defense enzymes such as peroxidase, phenylalanine ammonia lyase, chitinase and â-1,3glucanase in the leaves of the Som plant was also noticed in different varieties due to the treatment. B.pumilus also showed antagonistic activity in vitro against two important fungal pathogens, Pestalotiopsis dissemenata, casual organism of grey blight disease and Colletotrichum gleosporoides, casual organism of leaf blight disease of Som plant.

In vitro Sensitivity of Fungal Pathogens Isolated From Seed Samples of Jute (Corchorus sp.) and Mesta (Hibiscus sp.) Germplasm

1* 1 2AN Tripathi , SK Sarkar and PC Agarwal1Division of Crop Protection, Central Research Institute for Jute &

2Allied Fibers, Barrackpore, Kolkata- 700120 Plant Quarantine Division, National Bureau of Plant Genetic Resources, New Delhi-110012. E-mail; antripathi_patho@rediffmail.com

Seed health testing studies were conducted using 60 seed samples of jute and mesta comprising 15 each Corchours olitorius, C. capsularis, Hibiscus cannabinus and H. sabdariffa germplasm obtained from National Gene Bank, New Delhi (India) were subjected for seed health test. These seed samples were tested by Blotter Method and pure cultures of seed borne fungal pathogens were maintained on potato dextrose agar for further studies. The five fungal pathogens namely Alternaria alternata, Fusarium moniliforme, Macrophomina phaseolina, Phoma exigua and Sclerotium rolfsii were isolated.

Ten essential oils Citronella, Cedar wood, Cotton seed, Eugenol, Lemongrass, Linawool, Neem, Palmarosa, Patchouli and Winter green oil which are in commercial use were evaluated for their in vitro antifungal efficacy on five fungal pathogens. The order of efficacy of essential oils assayed by per cent of mycelial growth inhibition against test pathogens Eugenol oil was most effective and Cotton seed oil was least effective at test concentration of 1000 ppm. In general per cent mycelial growth inhibition was concentration dependent. Similarily, In vitro mycelial growth inhibition efficacy were carried out in five test isolates using biocontrol agents namely Trichoderma harzianum isolates (T1, T2 and T8) and mycelial growth inhibition efficacy of T. harzianum

Lead lecture –Biotic stress

Stress on Agriculture Education and Research System

SK Laha*, PM Bhattacharya and A Roy

Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal 736 165., Email: slahaubkv@yahoo.co.in

Present day agriculture in India is full of stress at various levels. The stress related to human factor is perhaps the most important of them. It is observed that in the farming community, the farmers by and large, are ignorant about most of the crop diseases, particularly at initial stage and thus they approach for any suggestion at the fag end when it is too late. Often insect damages are confused with diseases leading to selection of wrong pesticides. There is trend to apply over dose of pesticides which often leads to Phyto-toxicity. The farmers, knowingly or unknowingly, do not care for any waiting period after application of pesticide leading to high residual toxic products in their produce. Moreover, the equipments used for application, the method of application and the safety measures followed are all faulty in most of the cases. Another important factor is the over dependence on chemical methods of disease management. Often they approach the experts and demand for remedies involving application of chemicals. They are not satisfied if some cultural measures are suggested. The recent trend by many farmers has to apply over doses of fertilizers, particularly nitrogen which often makes it impossible to manage a disease by any means. For some diseases (e.g., late blight of potato) community approach is needed. In addition, majority of the farmers are of the habit of getting critical inputs free of cost and loose interest when the critical input is withdrawn even after being satisfied about the effectiveness of the suggested technology.

At the site of education, the teachers often fail to introduce students about disease in population. A few field visits are organized and the curriculum includes mostly laboratory based practical. The present course and curriculum has not been able to build up self confidence in students. The fault lies in not only unwillingness of most of the students to be attentive but also in the quality and way of sharing knowledge from teachers' end. Consequently, the training to students is by no means completed to develop human resources as per farmers' requirement.

In the context of research activities, in our country most of the research stations are not well equipped with many facilities required for field and laboratory work. Region specific problem oriented research programme is comparatively low. Rather execution of programme formulated at hierarchical system is going on. The fund flow in fundamental research has been lowered down during recent past in agricultural sector creating hindrance in finding actual cause in stress biology. The culture and ethics within the working force is also now questionable. Plagiarism in information generation along with predetermined and fabricated

results in research publications may also aggravate the negative impact at field level. It is therefore urgently needed to assess the entire perspective and re-orient the agriculture education research and extension system that will be complementary to farmers' requirement.

Lead lecture-abiotic stress

Alleviation of Salinity and Water Stress in Crop Plants by Osmo-Tolerant Plant Growth Promoting Rhizobacteria

U Chakraborty*, BN Chakraborty, AP Chakraborty and PL Dey

Plant Biochemistry Laboratory and Immuno -Phytopathology Laboratory, Department of Botany, University of North Bengal, Siliguri-734013, West Bengal, Email- chakrabortyusha@hotmail.com

A large number of bacteria were isolated from rhizosphere of different plants viz. Triticum aestium, Cynodon dactylon, Imperata cylindrical and Camellia sinensis. Paenibacillus polymyxa (TRS5), Bacillus megterium (TRS 7) and Ochrobactrum anthropi (TRS 2) obtained from the rhizosphere of tea were found to be highly salt-tolerant, when grown in nutrient broth medium supplemented with 10% NaCl and also exhibited PGPR characteristics. Besides, 9 isolates (S1-5 and N1-4) from rhizosphere of C. dactylon, 27 isolates from wheat rhizosphere (W1-27) and 18 isolates from I. cylindrica (IP1-18) were also found to be salt-tolerant. Those bacterial isolates showing positive responses in vitro were identified by morphological, biochemical and 16SrDNA sequencing to be Ochrobactrum pseudogregnonense (IP8), Bacillus safensis (W10) and Bacillus cereus (S4). Scanning electron microscopic observation and RAPD-PCR analysis of the isolates were done for microscopic and molecular characterization. In vitro PGPR tests such as phosphate solubilization, siderophore production, IAA, chitinase production showed positive results. W5, 10, 11, IP5, 8 and 23 also showed ACC deaminase activities. On the basis of in vitro PGPR tests, eight isolates (Bacillus cereus, B. safensis, O. pseudogregnonense, N2, N4, TRS-2, 5 and 7) were selected as potential salt-tolerant PGPR for field study to determine their ability to promote growth of plants under saline as well as water stress conditions. For in vivo studies on certain crops, Bacillus cereus was applied along with 200ml of 200mM NaCl to the rhizosphere of Vigna radiata, Cicer arietinum and Oryza sativa separately. Results revealed that the bacterium could promote growth, elicit antioxidant responses against salt stress as well as induce the activities of defense enzymes associated with ISR significantly. For salinity studies on wheat, aqueous suspensions of S4, N2, N4, TRS-2, TRS-7 and TRS-5 were applied thrice at an interval of one day to the rhizosphere of wheat plants which were already treated with 200mM NaCl solution. For water stress studies, B. safensis and O. pseudogregnonense which were found to be drought tolerant were selected and these could promote

J Mycol Plant Pathol, Vol. 42, No.4, 2012538

Abstracts of the papers presented at the National Symposium on “Biotic and Abiotic Stresses in Plants under Changing Climate Scenario” at

thEast Zone Meet, UBKV, Pundibari, Coochbehar (WB), 29-30 November, 2012

J Mycol Plant Pathol, Vol. 42, No.4, 2012 539

growth in terms of increase in root and shoot biomass, height of plants, yield, as well as increase in chlorophyll content. Besides, the wheat plants could withstand water stress more efficiently in presence of the bacteria as indicated by delay of appearance of wilting symptoms increases in RWC of treated water stressed plants. In case of both salinity and water stressed conditions, application of bacteria led to elevated antioxidant responses which were evident as elevated activities of enzymes such as catalase, peroxidase, ascorbate peroxidase, superoxide dismutase and glutathione reductase as well as increased accumulation of antioxidants such as carotenoids and ascorbate. Results clearly indicate that the ability of wheat plants to withstand water stress is enhanced by application of these bacteria which also function as plant growth promoting rhizobacteria. Thus, osmo-tolerant PGPR strains could be used in field condition in order to mitigate saline stress in crop plants as they are beneficial and also economically suitable for the cultivars than any other approaches like manipulation of stress associated gene expression and conventional plant breeding.

Invited lecture-biotic stress

Molecular Detection of Viral Diseases from Economically Important Crops and Allied Weeds of North East Indian Plains

*Aniruddha Saha , Bikram Saha, Piyali Sarkar, Prosenjit Chakraborty, Shibu das and Dipanwita

1Saha1Department of Botany, Deparment of Biotechnology, University of

North Bengal, India, Pin 734013. E-mail: asahanbu@yahoo.co.in

The north East Indian states are suitable for cultivation of several horticultural crops. The place is also known for its rich biodiversity. Diseases and pests are major limiting factors for cultivation of horticultural crops. Viral diseases also constitute substantially to limit the production. In the present study, an approach has been taken to detect viral pathogens of major horticultural crops like tomato, potato, papaya and bean and uncultivated plants like datura, jatropha, croton, acalypha and ageratum as a reservoir of viral pathogens. Genome sequencing of most conserved regions have been done for molecular detection of the viruses. Using universal primers, begomoviruses were detected from tomato, potato and uncultivated plants like datura, jatropha, croton, acalypha and ageratum. Four viruses namely Tobacco curly shoot virus (TbCSV), Tomato leaf curl New Delhi virus (ToLCNDV), Tomato leaf curl Bangladesh virus (ToCBV) and Tomato leaf curl Ranchi virus (ToLCRnV) have been provisionally identified from cultivated tomato. Tomato leaf curl New Delhi virus (ToLCNDV) was also provisionally identified from potato and datura plants growing in the region. The above mentioned viruses were not associated with papaya and bean. On the basis of sequencing of PCR amplified viral genome using RT-PCR kit Papaya ring spot virus (PRSV), Potato virus Y (PVY) and Bean common mosaic virus (BCMV) were detected in papaya, potato and bean respectively. Papaya ring spot virus type-P (PRSV-P) was confirmed following host range test. Several botanicals (plant extracts) were tested to control Bemisia tabaci, the vector of begomoviruses present in tomato fields. Out of the botanicals tested two botanicals could check the insect infestation in north East Indian field condition.

Induction of Plant Growth Promotion in Persea bombycina Kost by Bacillus pumilus

1 1* 1A Acharya , BN Chakraborty , U Chakraborty , J 2 2 3Rabha , DK Jha , HK Sharma

1Immouno-Phytopathology Laboratory, Department of Botany, 2University of North Bengal, Microbial Ecology Laboratory,

3Department of Botany, Gauhati University, Department of Biotechnology, Gauhati University. Email: bncnbu@gmail.com

Persea bombycina Kost, family Lauraceae, with the local name “Som” is one of the main primary host plants of muga silkworm (Antheraea assama), and has significant effects on the health and survival of the silkworms. A study was made to improve the health status of Som plant with the application of plant growth promoting rhizobacteria Bacillus pumilus (BRHS/C1) as foliar spray as well as directly applying it to the soil. Eight different varieties of Som plants viz. S1, S2, S3, S4, S5, S6, S7 and S8 were used in this study. An increase in height, number of leaves and branches in all the varieties were observed following the application of the bacterium. Increase in the level of the defense enzymes such as peroxidase, phenylalanine ammonia lyase, chitinase and â-1,3glucanase in the leaves of the Som plant was also noticed in different varieties due to the treatment. B.pumilus also showed antagonistic activity in vitro against two important fungal pathogens, Pestalotiopsis dissemenata, casual organism of grey blight disease and Colletotrichum gleosporoides, casual organism of leaf blight disease of Som plant.

In vitro Sensitivity of Fungal Pathogens Isolated From Seed Samples of Jute (Corchorus sp.) and Mesta (Hibiscus sp.) Germplasm

1* 1 2AN Tripathi , SK Sarkar and PC Agarwal1Division of Crop Protection, Central Research Institute for Jute &

2Allied Fibers, Barrackpore, Kolkata- 700120 Plant Quarantine Division, National Bureau of Plant Genetic Resources, New Delhi-110012. E-mail; antripathi_patho@rediffmail.com

Seed health testing studies were conducted using 60 seed samples of jute and mesta comprising 15 each Corchours olitorius, C. capsularis, Hibiscus cannabinus and H. sabdariffa germplasm obtained from National Gene Bank, New Delhi (India) were subjected for seed health test. These seed samples were tested by Blotter Method and pure cultures of seed borne fungal pathogens were maintained on potato dextrose agar for further studies. The five fungal pathogens namely Alternaria alternata, Fusarium moniliforme, Macrophomina phaseolina, Phoma exigua and Sclerotium rolfsii were isolated.

Ten essential oils Citronella, Cedar wood, Cotton seed, Eugenol, Lemongrass, Linawool, Neem, Palmarosa, Patchouli and Winter green oil which are in commercial use were evaluated for their in vitro antifungal efficacy on five fungal pathogens. The order of efficacy of essential oils assayed by per cent of mycelial growth inhibition against test pathogens Eugenol oil was most effective and Cotton seed oil was least effective at test concentration of 1000 ppm. In general per cent mycelial growth inhibition was concentration dependent. Similarily, In vitro mycelial growth inhibition efficacy were carried out in five test isolates using biocontrol agents namely Trichoderma harzianum isolates (T1, T2 and T8) and mycelial growth inhibition efficacy of T. harzianum

isolates were assessed by the formation of the inhibition zone against tested pathogens . The result of the in vitro inhibition showed that efficacy of isolate T1 (50-75%) was highest followed by T8 (50-73) and T (0-55).

Isolation and Identification of Endophytes from Groundnut (Arachis hypogaea L.) for Their Possible Use in Management of Biotic and Abiotic Stresses

KK Pal, R Dey, ET Janeesh, M Thomas, K Hudka, N Acharya and RB Rupapara,

Directorate of Groundnut Research, Ivnagar Road, PB No. 5, Junagadh 362 001, Gujarat

Groundnut, a major oilseed crop in India is cultivated predominantly as a rain-fed crop and as such the productivity is quite often affected by drought, high temperature, salinity, or combination of these factors and incidence of major soil-borne and foliar fungal diseases.

Of late, both bacterial and fungal endophytes have been reported to help the plants in alleviating the biotic and abiotic stresses, besides improving growth and yield. Among the bacterial endophytes inoculation of Pseudomonas pseudoalcaligenes has been reported to alleviate salinity stress in rice (Jha et al. 2010) and Bacillus megaterium promoted growth and yield in maize (Surette et al. 2003).

As some of the popular groundnut cultivars of groundnut tolerant to these stresses, attempts were made to identify candidate endophytes which could be useful in alleviating the biotic and abiotic stresses in groundnut.

From root, stem and seeds of groundnut cultivars viz., Girnar 2, TG37A (tolerant to moisture deficit stress), GG2 (tolerant to salinity) and the seeds of some other cultivars, such as, J11 (seed coat resistance to A. flavus), ICGS11, SG99 and germplasm accessions like NRCG 12431, 12962, 12732 (all tolerant to moisture deficit stress), etc., 131 bacterial and 20 fungal putative endophytes were isolated. Fifty-two bacterial and 20 fungal endophytes were characterised for tolerance of salinity and high temperature and also for antifungal activity in vitro. All the 52

obacterial and 20 fungal endophytes were able to grow at 50 C and 5% NaCl. Fourteen bacterial and two fungal isolates showed inhibitory activity on soil-borne fungal pathogens of groundnut viz., Aspergillus niger, Sclerotium rolfsii and Aspergillus flavus.

So far, 76 bacterial and 20 endophytes have been identified. Among the bacterial root endophytes, organisms belonging to Bacillus and Bacillus derived genera were predominant. Besides, Acinetobacter radioresistens, Staphylococcus sp., Kytococcus sp., Pseudomonas fluorescens, Enterobacter sp., Alcaligenes faecalis and a number of isolates belonging to uncultured bacterial clones were also obtained indicating that these organisms might be novel ones. Bacterial stem endophytes include isolates of Alcaligenes faecalis, Kocuria palustris, Brevundimonas sp., Pantoea agglomerans, Pseudomonas aeruginosa, Enterobacter ludwigii, Enterobacter cloacae, Staphylococcus sp., and a number of isolates of Bacillus and Bacillus-derived genera. The seed endophytes include Bacillus subtilis, Bacillus firmus, Pseudomonas sp., Bacillus tequilensis and Pseudomonas aeruginosa. As many of the isolated endophytes of groundnut showed tolerance of salinity and high temperature, besides the presence of plant growth promoting

traits and having antifungal properties, a few of these might be potential candidates for alleviating biotic and abiotic stresses in groundnut.

Phylogenetic Analysis among Trichoderma harzianum, T. asperellum and T. erinaceum and their Evaluation for Management of Sclerotial blight

PL Dey, K Sunar, U Chakraborty and BN Chakraborty

Immuno-Phytopathology Laboratory, Department of Botany, University of North Bengal, Siliguri 734013, Darjeeling, West Bengal, India

Ten isolates of Trichoderma harzianum, three of T. asperellum and four T. erinaceum obtained from forest soil, agricultural field and rhizosphere of plantation crops were characterized by morphological features as well as by bright field and scanning electron microscopy. In vitro tests of these isolates of Trichoderma sp. showed significant inhibition against Sclerotium rolfsii, Rhizoctonia solani, Fusarium oxysporum, F. solani, F. graminarium and Macrophomina phaseolina. They also exhibited exo and endo-chitinase activities. Their diversity was analyzed using RAPD-PCR and Denature Gradient Gel Electrophoresis (DGGE). The amplified DNA was sequenced and aligned against ex-type strains sequencings from TrichoBLAST /GenBank Trichoderma taxonomy. Consequently, a reliable phylogenetic tree was constructed containing isolates belonging to the T. harzianum T. asperellum and T. erinaceum clade. Multiple sequence alignment of rDNA gene of these Trichoderma isolates was carried out in BIOEDIT and MEGA-4 software to compare with other ex-types gene sequences and their evolutionary distances. The isolates which were positively identified as Trichoderma harzianum, T. asperellum and T. erinaceum were used as an out-group in these analyses. The isolates were evaluated for the management of sclerotial blight of Vigna radiata in green house and field conditions. Direct application of these isolates in the rhizosphere of Vigna radiata and Phaseolus vulgaris significantly reduced sclerotial blight incidence by enhancing key defense enzymes such as chitinase, â 1-3 glucanase, and peroxidase and phenylalanine ammonia lyase.

Endophytes, organisms belonging to Bacillus and Bacillus derived genera were predominant. Besides, Acinetobacter radioresistens, Staphylococcus sp., Kytococcus sp., Pseudomonas fluorescens, Enterobacter sp., Alcaligenes faecalis and a number of isolates belonging to uncultured bacterial clones were also obtained indicating that these organisms might be novel ones. Bacterial stem endophytes include isolates of Alcaligenes faecalis, Kocuria palustris, Brevundimonas sp., Pantoea agglomerans, Pseudomonas aeruginosa, Enterobacter ludwigii, Enterobacter cloacae, Staphylococcus sp., and a number of isolates of Bacillus and Bacillus-derived genera. The seed endophytes include Bacillus subtilis, Bacillus firmus, Pseudomonas sp., Bacillus tequilensis and Pseudomonas aeruginosa.

As many of the isolated endophytes of groundnut showed tolerance of salinity and high temperature, besides the presence of plant growth promoting traits and having antifungal properties, a few of these might be potential candidates for alleviating biotic and abiotic stresses in groundnut.

J Mycol Plant Pathol, Vol. 42, No.4, 2012540 J Mycol Plant Pathol, Vol. 42, No.4, 2012 541

Seed Infection of Jute (Corchorus olitorius, C. capsularis) and its Management

Rajib Kumar De* and RK Mandal

Crop Protection Division, Central Research Institute for Jute and Allied Fibres, (Indian Council of Agricultural Research), Nilganj, Barrackpore, Kolkata 700 120. Email:rkde@rediffmail.com

Jute (Corchorus olitorius L. and C. capsularis.) is a unique plant in the sense that it requires two separate crops to produce commercial fibre or seed with different agronomic practices for each of them. Fibre crop is grown in the eastern part of India as pre-Kharif crop whereas seed crop is normally grown in the states of Maharashtra and Andhra Pradesh. Then seeds produced there have to travel long distance to be sown in the eastern part of India every year. Tossa jute is the most widely cultivated in all the jute growing areas of India. Stem rot caused by Macrophomina phaseolina (Tassi) Goid. is the economically most important disease causing reduction in yield (10 - 25 % loss) and deterioration of fibre quality. At times, this disease is a major constraint in some belts threatening both fibre and seed crops. Though commonly known as stem rot, symptoms of stem rot include seedling blight, damping off, leaf blight, collar rot, and stem rot, spot on pod and root rot. Seed transmission is one of the most important modes of dissemination of plant diseases around the world. Besides stem rot, black band caused by Botryodiplodia theobromae and anthracnose caused by Colletotrichum gloeosporiodes, C. corchoriare the other seed-borne diseases of jute. In the present investigation, the extent of seed-borne pathogens, susceptible crop stage and management of seed infection in jute were studied.

Seed samples were collected from different sources, viz., Andhra Pradesh, Maharashtra

and local markets, tested by standard blotter method (of ISTA) under 12 hours alternate cycles of NUV and darkness, incubated

ofor 8 days at temperature of 25+ C for identification of fungal pathogens. Two field experiments were conducted at CRIJAF, Barrackpore using variety JRO 524 to (1) identify the most susceptible stage of jute seed infection by B. theobromae and M. phaseolina with artificial inoculation separately with spores of both pathogens at pre-flowering, 50 % flowering, pod formation, just before seed maturity and control, i.e., no inoculation, (2) manage jute seed infection by two seed-borne pathogens, four fungicides, namely, carbendazim, copper oxychloride, mancozeb, metalaxyl were sprayed. RBD with five replications was used in both field experiments.

All seed samples showed presence of both M. phaseolinaandB. theobromae. The extent of infection was however very low (0.25 to 7.25%). Other fungal pathogens recorded in jute seed were Colletotrichum gloeosporiodes, C. corchori, Curvularia, Sclerotium rolfsii (contamination) and different species of Fusarium and Alternaria. Highest seed infection by M. phaseolinaandB. theobromae place when inoculation was done at pod formation stage followed by at 50 % flowering, before seed maturity and pre-flowering stage of inoculation. Pod formation was the most vulnerable stage for seed infection for most of the seed borne pathogens of jute and measure taken at this stage produced healthy seeds. M. phaseolina and B. theobromae very sensitive to carbendazim and complete growth inhibition was obtained even at as low as 10 ppm concentration, whereas with copper oxychloride no inhibition was obtained up to 200 ppm. Carbendazim was most effective fungicide showing mean seed

infection percentage only 0.8 (90.7% over check) followed by copper oxychloride with 1.2 % infection (86.5% control). By a single spray of carbendazim or copper oxychloride at pod formation stage, management of seed infection by both the pathogens may be possible.

Plant Parasitic Nematodes: An Emerging Problem under Changing Climate and Agricultural Practices

Ajoy K Ganguly and Tushar K Dutta

Division of Nematology, Indian Agricultural Research Institute, New Delhi-110012

Plant parasitic nematodes are gaining considerable importance worldwide due to their devastating effects on crops leading to major economic and social impacts. Because of their size nematodes have remained a little known group. Much of the damages remained unappreciated since the symptoms are mistaken for nutrient or water deficits, salinity or other soil disorders. According to the world estimates the 20 major life sustaining crops suffer 10.7% yield losses due to nematodes, and other 20 economically important crops suffer 14% losses, the average amounts to 12.3%. While the average losses in developing nations including India is 14.6% (Sasser, 1989). According to trials in the 1960s, in Rajasthan alone the molya disease due to Heterodera avenae caused crop losses worth Rs. 400 million at current prices. Even ear cockle nematode, Anguina tritici caused less than 1% average loss of wheat amounts to Rs. 750 million at current prices. Similarly, root lesion nematode, Pratylenchus coffee cause damage worth of Rs. 200 million on coffee. At the global level root-knot nematodes, Meloidogyne incognita is the major hindrance in crop production as rarely any crop is free from its damage. In India M. incognita causes cause huge lose in vegetables like tomato, brinjal, okra, cucurbits etc. Rice root-knot nematode, M. graminicola has emerged as a major problem in rice-wheat agro-ecosystem especially in south-east Asia. Diseases caused by nematodes are divided into subgroups according to their habitat and parasitic habit (sedentary, migratory, endo and ecto parasites). Majority of the plant parasitic nematodes are ectoparasites include Tylenchorhynchus, Helicotylenchus, Hemicriconemoides, Paratylenchus, Xiphinema, Longidorus, Trichodorus etc. some of the important migratory nematodes of above ground plant parts are Aphelenchoides besseyi, Ditylenchus dipsaci, D. angustus, Rhynchophorus palmarum, Bursaphelenchus xylophilus etc. Parasitic stages of some genera like Tylenchulus and Rotylenchulus partially enter roots of citrus and castor known as sedentary semi-endoparasites. While sedentary endoparasies like root-knot and cysts complete their life cycle almost within the root itself followed by production of medium to large size galls in case of Meloidogyne incurring heavy damage. Besides the direct damage, nematodes also predispose plants to a variety of other pathogens especially bacteria and fungi forming disease complexes. Some of them are tundu, vascular wilt, damping off, cortical rot, black shank etc. Other than that species of Xiphinema, Longidorus, and Trichodorus are known to transmit soil borne viruses in plants leading to diseases like grapevine fan leaf, raspberry ring spot, tobacco black ring etc. Under the changing climate and agricultural scenario, a sustainable management approach need to be adopted with an objective to maintain nematode population densities at the levels below the economic injury threshold or to reduce their levels such as to derive maximum profits out of the management cost is incurred.

isolates were assessed by the formation of the inhibition zone against tested pathogens . The result of the in vitro inhibition showed that efficacy of isolate T1 (50-75%) was highest followed by T8 (50-73) and T (0-55).

Isolation and Identification of Endophytes from Groundnut (Arachis hypogaea L.) for Their Possible Use in Management of Biotic and Abiotic Stresses

KK Pal, R Dey, ET Janeesh, M Thomas, K Hudka, N Acharya and RB Rupapara,

Directorate of Groundnut Research, Ivnagar Road, PB No. 5, Junagadh 362 001, Gujarat

Groundnut, a major oilseed crop in India is cultivated predominantly as a rain-fed crop and as such the productivity is quite often affected by drought, high temperature, salinity, or combination of these factors and incidence of major soil-borne and foliar fungal diseases.

Of late, both bacterial and fungal endophytes have been reported to help the plants in alleviating the biotic and abiotic stresses, besides improving growth and yield. Among the bacterial endophytes inoculation of Pseudomonas pseudoalcaligenes has been reported to alleviate salinity stress in rice (Jha et al. 2010) and Bacillus megaterium promoted growth and yield in maize (Surette et al. 2003).

As some of the popular groundnut cultivars of groundnut tolerant to these stresses, attempts were made to identify candidate endophytes which could be useful in alleviating the biotic and abiotic stresses in groundnut.

From root, stem and seeds of groundnut cultivars viz., Girnar 2, TG37A (tolerant to moisture deficit stress), GG2 (tolerant to salinity) and the seeds of some other cultivars, such as, J11 (seed coat resistance to A. flavus), ICGS11, SG99 and germplasm accessions like NRCG 12431, 12962, 12732 (all tolerant to moisture deficit stress), etc., 131 bacterial and 20 fungal putative endophytes were isolated. Fifty-two bacterial and 20 fungal endophytes were characterised for tolerance of salinity and high temperature and also for antifungal activity in vitro. All the 52

obacterial and 20 fungal endophytes were able to grow at 50 C and 5% NaCl. Fourteen bacterial and two fungal isolates showed inhibitory activity on soil-borne fungal pathogens of groundnut viz., Aspergillus niger, Sclerotium rolfsii and Aspergillus flavus.

So far, 76 bacterial and 20 endophytes have been identified. Among the bacterial root endophytes, organisms belonging to Bacillus and Bacillus derived genera were predominant. Besides, Acinetobacter radioresistens, Staphylococcus sp., Kytococcus sp., Pseudomonas fluorescens, Enterobacter sp., Alcaligenes faecalis and a number of isolates belonging to uncultured bacterial clones were also obtained indicating that these organisms might be novel ones. Bacterial stem endophytes include isolates of Alcaligenes faecalis, Kocuria palustris, Brevundimonas sp., Pantoea agglomerans, Pseudomonas aeruginosa, Enterobacter ludwigii, Enterobacter cloacae, Staphylococcus sp., and a number of isolates of Bacillus and Bacillus-derived genera. The seed endophytes include Bacillus subtilis, Bacillus firmus, Pseudomonas sp., Bacillus tequilensis and Pseudomonas aeruginosa. As many of the isolated endophytes of groundnut showed tolerance of salinity and high temperature, besides the presence of plant growth promoting

traits and having antifungal properties, a few of these might be potential candidates for alleviating biotic and abiotic stresses in groundnut.

Phylogenetic Analysis among Trichoderma harzianum, T. asperellum and T. erinaceum and their Evaluation for Management of Sclerotial blight

PL Dey, K Sunar, U Chakraborty and BN Chakraborty

Immuno-Phytopathology Laboratory, Department of Botany, University of North Bengal, Siliguri 734013, Darjeeling, West Bengal, India

Ten isolates of Trichoderma harzianum, three of T. asperellum and four T. erinaceum obtained from forest soil, agricultural field and rhizosphere of plantation crops were characterized by morphological features as well as by bright field and scanning electron microscopy. In vitro tests of these isolates of Trichoderma sp. showed significant inhibition against Sclerotium rolfsii, Rhizoctonia solani, Fusarium oxysporum, F. solani, F. graminarium and Macrophomina phaseolina. They also exhibited exo and endo-chitinase activities. Their diversity was analyzed using RAPD-PCR and Denature Gradient Gel Electrophoresis (DGGE). The amplified DNA was sequenced and aligned against ex-type strains sequencings from TrichoBLAST /GenBank Trichoderma taxonomy. Consequently, a reliable phylogenetic tree was constructed containing isolates belonging to the T. harzianum T. asperellum and T. erinaceum clade. Multiple sequence alignment of rDNA gene of these Trichoderma isolates was carried out in BIOEDIT and MEGA-4 software to compare with other ex-types gene sequences and their evolutionary distances. The isolates which were positively identified as Trichoderma harzianum, T. asperellum and T. erinaceum were used as an out-group in these analyses. The isolates were evaluated for the management of sclerotial blight of Vigna radiata in green house and field conditions. Direct application of these isolates in the rhizosphere of Vigna radiata and Phaseolus vulgaris significantly reduced sclerotial blight incidence by enhancing key defense enzymes such as chitinase, â 1-3 glucanase, and peroxidase and phenylalanine ammonia lyase.

Endophytes, organisms belonging to Bacillus and Bacillus derived genera were predominant. Besides, Acinetobacter radioresistens, Staphylococcus sp., Kytococcus sp., Pseudomonas fluorescens, Enterobacter sp., Alcaligenes faecalis and a number of isolates belonging to uncultured bacterial clones were also obtained indicating that these organisms might be novel ones. Bacterial stem endophytes include isolates of Alcaligenes faecalis, Kocuria palustris, Brevundimonas sp., Pantoea agglomerans, Pseudomonas aeruginosa, Enterobacter ludwigii, Enterobacter cloacae, Staphylococcus sp., and a number of isolates of Bacillus and Bacillus-derived genera. The seed endophytes include Bacillus subtilis, Bacillus firmus, Pseudomonas sp., Bacillus tequilensis and Pseudomonas aeruginosa.

As many of the isolated endophytes of groundnut showed tolerance of salinity and high temperature, besides the presence of plant growth promoting traits and having antifungal properties, a few of these might be potential candidates for alleviating biotic and abiotic stresses in groundnut.

J Mycol Plant Pathol, Vol. 42, No.4, 2012540 J Mycol Plant Pathol, Vol. 42, No.4, 2012 541

Seed Infection of Jute (Corchorus olitorius, C. capsularis) and its Management

Rajib Kumar De* and RK Mandal

Crop Protection Division, Central Research Institute for Jute and Allied Fibres, (Indian Council of Agricultural Research), Nilganj, Barrackpore, Kolkata 700 120. Email:rkde@rediffmail.com

Jute (Corchorus olitorius L. and C. capsularis.) is a unique plant in the sense that it requires two separate crops to produce commercial fibre or seed with different agronomic practices for each of them. Fibre crop is grown in the eastern part of India as pre-Kharif crop whereas seed crop is normally grown in the states of Maharashtra and Andhra Pradesh. Then seeds produced there have to travel long distance to be sown in the eastern part of India every year. Tossa jute is the most widely cultivated in all the jute growing areas of India. Stem rot caused by Macrophomina phaseolina (Tassi) Goid. is the economically most important disease causing reduction in yield (10 - 25 % loss) and deterioration of fibre quality. At times, this disease is a major constraint in some belts threatening both fibre and seed crops. Though commonly known as stem rot, symptoms of stem rot include seedling blight, damping off, leaf blight, collar rot, and stem rot, spot on pod and root rot. Seed transmission is one of the most important modes of dissemination of plant diseases around the world. Besides stem rot, black band caused by Botryodiplodia theobromae and anthracnose caused by Colletotrichum gloeosporiodes, C. corchoriare the other seed-borne diseases of jute. In the present investigation, the extent of seed-borne pathogens, susceptible crop stage and management of seed infection in jute were studied.

Seed samples were collected from different sources, viz., Andhra Pradesh, Maharashtra

and local markets, tested by standard blotter method (of ISTA) under 12 hours alternate cycles of NUV and darkness, incubated

ofor 8 days at temperature of 25+ C for identification of fungal pathogens. Two field experiments were conducted at CRIJAF, Barrackpore using variety JRO 524 to (1) identify the most susceptible stage of jute seed infection by B. theobromae and M. phaseolina with artificial inoculation separately with spores of both pathogens at pre-flowering, 50 % flowering, pod formation, just before seed maturity and control, i.e., no inoculation, (2) manage jute seed infection by two seed-borne pathogens, four fungicides, namely, carbendazim, copper oxychloride, mancozeb, metalaxyl were sprayed. RBD with five replications was used in both field experiments.

All seed samples showed presence of both M. phaseolinaandB. theobromae. The extent of infection was however very low (0.25 to 7.25%). Other fungal pathogens recorded in jute seed were Colletotrichum gloeosporiodes, C. corchori, Curvularia, Sclerotium rolfsii (contamination) and different species of Fusarium and Alternaria. Highest seed infection by M. phaseolinaandB. theobromae place when inoculation was done at pod formation stage followed by at 50 % flowering, before seed maturity and pre-flowering stage of inoculation. Pod formation was the most vulnerable stage for seed infection for most of the seed borne pathogens of jute and measure taken at this stage produced healthy seeds. M. phaseolina and B. theobromae very sensitive to carbendazim and complete growth inhibition was obtained even at as low as 10 ppm concentration, whereas with copper oxychloride no inhibition was obtained up to 200 ppm. Carbendazim was most effective fungicide showing mean seed

infection percentage only 0.8 (90.7% over check) followed by copper oxychloride with 1.2 % infection (86.5% control). By a single spray of carbendazim or copper oxychloride at pod formation stage, management of seed infection by both the pathogens may be possible.

Plant Parasitic Nematodes: An Emerging Problem under Changing Climate and Agricultural Practices

Ajoy K Ganguly and Tushar K Dutta

Division of Nematology, Indian Agricultural Research Institute, New Delhi-110012

Plant parasitic nematodes are gaining considerable importance worldwide due to their devastating effects on crops leading to major economic and social impacts. Because of their size nematodes have remained a little known group. Much of the damages remained unappreciated since the symptoms are mistaken for nutrient or water deficits, salinity or other soil disorders. According to the world estimates the 20 major life sustaining crops suffer 10.7% yield losses due to nematodes, and other 20 economically important crops suffer 14% losses, the average amounts to 12.3%. While the average losses in developing nations including India is 14.6% (Sasser, 1989). According to trials in the 1960s, in Rajasthan alone the molya disease due to Heterodera avenae caused crop losses worth Rs. 400 million at current prices. Even ear cockle nematode, Anguina tritici caused less than 1% average loss of wheat amounts to Rs. 750 million at current prices. Similarly, root lesion nematode, Pratylenchus coffee cause damage worth of Rs. 200 million on coffee. At the global level root-knot nematodes, Meloidogyne incognita is the major hindrance in crop production as rarely any crop is free from its damage. In India M. incognita causes cause huge lose in vegetables like tomato, brinjal, okra, cucurbits etc. Rice root-knot nematode, M. graminicola has emerged as a major problem in rice-wheat agro-ecosystem especially in south-east Asia. Diseases caused by nematodes are divided into subgroups according to their habitat and parasitic habit (sedentary, migratory, endo and ecto parasites). Majority of the plant parasitic nematodes are ectoparasites include Tylenchorhynchus, Helicotylenchus, Hemicriconemoides, Paratylenchus, Xiphinema, Longidorus, Trichodorus etc. some of the important migratory nematodes of above ground plant parts are Aphelenchoides besseyi, Ditylenchus dipsaci, D. angustus, Rhynchophorus palmarum, Bursaphelenchus xylophilus etc. Parasitic stages of some genera like Tylenchulus and Rotylenchulus partially enter roots of citrus and castor known as sedentary semi-endoparasites. While sedentary endoparasies like root-knot and cysts complete their life cycle almost within the root itself followed by production of medium to large size galls in case of Meloidogyne incurring heavy damage. Besides the direct damage, nematodes also predispose plants to a variety of other pathogens especially bacteria and fungi forming disease complexes. Some of them are tundu, vascular wilt, damping off, cortical rot, black shank etc. Other than that species of Xiphinema, Longidorus, and Trichodorus are known to transmit soil borne viruses in plants leading to diseases like grapevine fan leaf, raspberry ring spot, tobacco black ring etc. Under the changing climate and agricultural scenario, a sustainable management approach need to be adopted with an objective to maintain nematode population densities at the levels below the economic injury threshold or to reduce their levels such as to derive maximum profits out of the management cost is incurred.

Identi f icat ion of Lenti l Genotype for Augmenting Arbuscular mycorrhizal Fungal (AMF) Spore Population Density and Species Diversity

1BN Panja*, S Ngomle, J Saha and R Nath1Department of Plant Pathology, Department of Agronomy, Bidhan

Chandra Krishi Viswavidyalaya, Mohanpur - 741235, Nadia, West Bengal, India. Email: birenpanja@rediffmail.com

Arbuscular mycorrhizal fungal (AMF) root colonization intensity, spore population density, species distribution, richness and diversity of forty lentil genotypes grown under field condition were studied. Spore population density (varied from 22 – 81 per 30 g) and root colonization intensity (ranged from 55.1 – 96.2%) of genotypes were found highest in L- 338 and Hull – 57 whereas the lowest with L-317 and L – 223 respectively. Based on spore population density and root colonization intensity, ten, twenty four and six genotypes and zero, one and thirty nine genotypes were placed under low, medium and high categories respectively. A total of eighteen AMF spores types extracted, the highest fifteen number of AMF spore types was observed in the rhizosphere of L-226 and L-338 genotypes whereas the lowest five in L-240 and L-317. Glomus sp. type 6 was found to appear in higher percentage, distributed in thirty nine genotype rhizospheres and was dominant in the rhizosphere of L-317 (36.0%). At the same time, AMF spore type Glomus aggregatum appeared in 0.4 % and was present in the

rhizosphere of only four genotypes. Species richness, diversity and evenness of AM fungi varied from 5 – 15 (maximum with L-226 and L-338), 1.53 - 2.66 (maximum L-248 and L-338) and 0.5 -1.0 (maximum with L-248 and L-338) respectively. Five, nine and twenty six lentil genotypes were placed under low, medium and high species richness categories; seven, twenty six and seven genotypes under low, medium and high species diversity categories; four, twenty two and fourteen genotypes under low, medium and high species evenness categories respectively. All forty lentil genotypes along with eighteen AMF spore types when subjected to principal component analysis, eight components accommodating 77.9% of total variation were obtained. Lentil genotype L - 338 was identified as the most preferred host for its significant influence on the abundance on majority of the AMF spores types followed by genotype L- 340 and L- 311. Hence, the lentil genotype L – 338 could be selected as promising genotypes for the enhancement of AMF spore population density as well as for conservation of AMF species diversity.

Evaluation of Cost Effective and Eco-Friendly Weed Control Measures in Jute through On-Farm Trial

Biplab Mitra & Saikat Mookherjee

Cooch Behar Krishi Vigyan Kendra,Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, 736 165, West Bengal

Jute is a major cash crop in Terai region of West Bengal. High pre-monsoon shower coupled with high humidity results in huge weed growth which offers a strong competition to jute for several growth factors and farmers have to go for a huge expenditure for controlling those weeds. Keeping these in mind, an on-farm trial was carried out for two consecutive years during pre-Kharif 2010 &11 at three villages of Cooch Behar District. In this OFT, straw

mulching after thinning and application of post-emergence herbicides were assessed against the farmers' practice of hand weeding only. The experiment was laid out in Randomized Block Design (RBD) with eight replicates. The major weeds in the experimental fields were Cynodon dactylon, Digitaria ciliaris, Setaria glauca, Cyperus rotundus, Cyperus iria, Ageratum conyzoides, Ludwigia parviflora, Polygonum persicaria, etc. It was revealed that post emergence application of Quizalofop ethyl 5% @50 g a.i./ha at 15-20 DAS followed by one hand weeding produced significantly higher yield (33.90 q/ha) than farmers' practice (31.17 q/ha). The chemical treatment was found to be the most economic options (B: C ratio 2.79) against straw mulch treated plots (B: C ratio 2.55) and farmers' practice (B:C ratio 2.04). However, no significant difference in yield was achieved under chemical treated plots and mulched plots.

Management of Sheath Blight of Rice using Local Trichoderma Isolates of the Old Alluvial Zone of North Bengal

Goutam Mondal

Regional Research Station (Old Alluvial Zone), Uttar Banga Krishi Viswavidyalaya, Majhian, Patiram-733133, Dakshin Dinajpur, WB, India. Email: gm_rrsubkv@yahoo.co.in

Sheath blight of rice caused by Rhizoctonia solani Kühn is one of the major constraints for rice cultivation in old alluvial zone of North Bengal causing 5-70% loss in every year. Five biocontrol agents of Trichoderma spp. were isolated from this agro ecological zone and were identified after dual culture test against R. solani. A talc based bioformulation of Trichoderma spp. was prepared with

8 3x10 cfu to use in a field experiment. The experimental field was designed as split plot, divided into two blocks for each of 3 replications and one block of each replication was green manured with Dhaincha [Sesbania aculeata (Willd.)Pers]. Germinated seed and seedling of rice (cv. Swarna) were treated with the bioformulation @5g/l of water. For soil application, bioformulation @7.5kg/ha was mixed in soil at the time of final land preparation. Two commonly used fungicides, namely, Hexaconazol 5EC @2.0ml/l and Carbendazim 50WP @1ml/l were taken as check along with another check plot where no treatment was given. In the field experiment, all the bioformulations of Trichoderma spp. were found effective to increase the yield (12.50% to 23.14%) significantly over check plots and the isolate, Trichoderma sp. B18 was given the highest yield. Again, the efficacy of the biocontrol agents was significantly greater in the blocks with green manured than the blocks without green manured. The incidence disease was significantly reduced with 46.32% to 70.54% on application of bioagent and two fungicides, Hexaconazol 5EC and Carbendazim 50WP comparing with the check plot. It was also observed that the all biocontrol agents were found significantly effective than the fungicides, where the Trichoderma sp. B18 and Trichoderma sp. B16 was performed better in disease reduction. Therefore, the fungal biocontrol agents could be used as biofungicides for the management of sheath blight of rice as well as biofertilizer.

Analysis of Core Coat Protein Gene Sequences Associated with Yellow Vein Mosaic Diseases of Weed Species in North-East Indian Plains

Prosenjit Chakraborty, Bikram Saha, Dipanwita 1 *Saha , Aniruddha Saha

J Mycol Plant Pathol, Vol. 42, No.4, 2012542 J Mycol Plant Pathol, Vol. 42, No.4, 2012 543

Department of Botany, University of North Bengal, India, Pin- 734013, 1Department of Biotechnology, University of North Bengal, India, Pin- 734013. E-mail: asahanbu@yahoo.co.in

Croton bonplandianum Baill., Acalypha indica L. and Ageratum conyzoides L. are the common weeds, grown in and around the cultivated fields of sub-Himalayan north-east Indian plains. Yellow vein mosaic diseases caused by begomoviruses are often associated with the weeds and may act as reservoirs of crop infecting begomoviruses. To find correlation of the weed infecting begomoviruses with crop infecting begomoviruses the present study was under taken. The core coat protein gene sequences are known to be useful in Begomovirus classification and provisional identification of the begomoviruses. Cloning and sequencing of the core CP gene of the three infected samples (C. bonplandianum, A. indica and A. conyzoides) were done using two universal primer sets (AV494 and AC1048) to partially characterize the Begomovirus complexes associated with these weed species from sub-Himalayan north-east India plains. Core CP genes were found to be amplified from all the naturally infecting weed samples tested. Sequence analysis study and phylogenetic analysis of the present Begomovirus complexes revealed significant variation among their sequences, although causing the same yellow vein mosaic diseases and also exhibited closeness to weed infecting and crop infecting begomoviruses.

Molecular Detection and Identification of Potyviruses Infecting Papaya and Potato Growing in North-East Indian Plains

Shibu Das, Bikram Saha, Piyali Sarkar, Dipanwita 1 *Saha and Aniruddha Saha

Department of Botany, University of North Bengal, India, Pin- 734013, 1Department of Biotechnology, University of North Bengal, India, Pin- 734013. E-mail: asahanbu@yahoo.co.in

Papaya and potato are extensively cultivated vegetable crops in India. A severe mosaic disease of papaya and potato with significant disease incidence was observed during the survey of different areas of north-east Indian plains. Infected papaya plants showed mosaic and string formation in leaves, pale oily greasy streaks on stems and ring spots on the fruits. Foliar mosaic and stunting of plants was observed in case of potato plants. cDNA was prepared from the RNA extracted from papaya and potato leaves. Potyvirus primers (CP9502 and CPUP) were used to amplify the virus genome in PCR. A positive PCR amplification product is obtained from all the samples tested. PCR amplicons were cloned and sequenced (GenBank accession no. JX 567310 for papaya and JX945850 for potato). The sequence data analysis of papaya revealed highest 92% nucleotide sequence identity with Papaya ring spot virus type P (PRSV-P) and potato samples showed highest 99% nucleotide sequence identity with Potato virus Y (PV-Y). The phylogenetic analysis also showed closest relationship of the isolates having accession nos JX 567310 and JX945850 with various variants of PRSV and PVY respectively. On the basis of highest nucleotide sequence identity and closest relationships with PRSV and PVY, the virus isolates were considered as potyviruses.

Role of Biochemical and Nutritional Parameters of Piper betle L. Leaf in the Resistance to White Fly Species Singhiella pallida Singh

T Dhar, PM Bhattacharya* and SK Senapati

Department of Agricultural Entomology and Plant Pathology*, Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar, West Bengal

Betelvine (Piper betle L.) is a perennial, dioecious evergreen creeper, grown in shady condition with warm and humid climate under conservatory. It is an important cash crop of rural India, which has immense potentiality in medicinal industry due to presence of wide array of primary and secondary plant metabolites in its leaf. White fly, Singhiella pallida Singh (Aleyrodidae: Hemiptera) is an important pest, found infesting the crop for the presence of micro-climate within the conservatory throughout the year, thus causing huge crop loss. Screening of betelvine cultivars for its resistance to S. pallida was carried out at the Research Farm of Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar, and West Bengal, India in the consecutive two years 2009-2010. Emphasis was given to find out the possible reasons of differential feeding preference of the pest by bio-chemical analysis of the betel leaf. Nine 'Bangla type cultivars and two 'Sanchi' type cultivars were used for screening to elucidate their resistance against the white fly, both Sanchi type cultivars viz. Simurali Sanchi and Halisahar Sanchi showed high resistance against the pest throughout the period of investigation. However, Simurali Sanchi was revealed more resistant than Halisahar Sanchi. In contrary, 'Bangla' type variety Simurali Golebhavna was noticed as most susceptible cultivar. Two 'Bangla' type cultivars namely Bagehot Local and Simurali Havana exhibited moderate resistance to white fly, while rest six 'Bangla' type cultivars were highly or moderately susceptible to the pest. Most of the biochemical and nutritional parameters had an important role in fluctuation of the white fly population. Phenol, ortho-dihydroxy (OD) phenol, polyphenol (PPO) and peroxidase (POD) activities in leaves were inversely correlated with the white fly population, while a positive response was recorded to leaf protein, nitrogen and phosphorus. Both the resistant varieties contained higher amount of phenol and OD phenol content as well as higher PPO and POD activities, resulting in low level of the white fly infestation. However, high protein, nitrogen concentration, nitrogen and phosphorus content in unit area of leaf were noticed in the susceptible cultivars, which induced high level infestation of the white fly. So far as cumulative role of the biochemical and nutritional parameters when taken into consideration, PPO and OD phenol have been identified most important factors in population fluctuation of the white fly; contributing 96.9% of total variation among the populations.

Turcicum Leaf Blight of Maize: Occurrence and Management under North Bengal Situation

Sajeed Ali and AK Chowdhury

Department of Plant Pathology, Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar, 736 165, West Bengal

Maize (Zea mays L.) is a miracle C4 cereal crop belonging to graminaceous family. It and has a very high yield potential and grown throughout the world from temperate to tropic regions. In West Bengal, Maize is cultivated both in Darjeeling Hills and Terai Zone of West Bengal; in hills it is cultivated as rabi crop. Farmers start sowing of seeds from mid of February to mid of March as rainfed crop, the growing period coincides with monsoon and hot summers which makes plant more liable to different diseases. There are numerous foliar blights diseases reported on maize, among them Turcicum Leaf Blight (TLB) disease caused by Exerohilum turcicum is important because yield losses as high as 60 % have been reported on susceptible cultivar. The pathogen is

Identi f icat ion of Lenti l Genotype for Augmenting Arbuscular mycorrhizal Fungal (AMF) Spore Population Density and Species Diversity

1BN Panja*, S Ngomle, J Saha and R Nath1Department of Plant Pathology, Department of Agronomy, Bidhan

Chandra Krishi Viswavidyalaya, Mohanpur - 741235, Nadia, West Bengal, India. Email: birenpanja@rediffmail.com

Arbuscular mycorrhizal fungal (AMF) root colonization intensity, spore population density, species distribution, richness and diversity of forty lentil genotypes grown under field condition were studied. Spore population density (varied from 22 – 81 per 30 g) and root colonization intensity (ranged from 55.1 – 96.2%) of genotypes were found highest in L- 338 and Hull – 57 whereas the lowest with L-317 and L – 223 respectively. Based on spore population density and root colonization intensity, ten, twenty four and six genotypes and zero, one and thirty nine genotypes were placed under low, medium and high categories respectively. A total of eighteen AMF spores types extracted, the highest fifteen number of AMF spore types was observed in the rhizosphere of L-226 and L-338 genotypes whereas the lowest five in L-240 and L-317. Glomus sp. type 6 was found to appear in higher percentage, distributed in thirty nine genotype rhizospheres and was dominant in the rhizosphere of L-317 (36.0%). At the same time, AMF spore type Glomus aggregatum appeared in 0.4 % and was present in the

rhizosphere of only four genotypes. Species richness, diversity and evenness of AM fungi varied from 5 – 15 (maximum with L-226 and L-338), 1.53 - 2.66 (maximum L-248 and L-338) and 0.5 -1.0 (maximum with L-248 and L-338) respectively. Five, nine and twenty six lentil genotypes were placed under low, medium and high species richness categories; seven, twenty six and seven genotypes under low, medium and high species diversity categories; four, twenty two and fourteen genotypes under low, medium and high species evenness categories respectively. All forty lentil genotypes along with eighteen AMF spore types when subjected to principal component analysis, eight components accommodating 77.9% of total variation were obtained. Lentil genotype L - 338 was identified as the most preferred host for its significant influence on the abundance on majority of the AMF spores types followed by genotype L- 340 and L- 311. Hence, the lentil genotype L – 338 could be selected as promising genotypes for the enhancement of AMF spore population density as well as for conservation of AMF species diversity.

Evaluation of Cost Effective and Eco-Friendly Weed Control Measures in Jute through On-Farm Trial

Biplab Mitra & Saikat Mookherjee

Cooch Behar Krishi Vigyan Kendra,Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, 736 165, West Bengal

Jute is a major cash crop in Terai region of West Bengal. High pre-monsoon shower coupled with high humidity results in huge weed growth which offers a strong competition to jute for several growth factors and farmers have to go for a huge expenditure for controlling those weeds. Keeping these in mind, an on-farm trial was carried out for two consecutive years during pre-Kharif 2010 &11 at three villages of Cooch Behar District. In this OFT, straw

mulching after thinning and application of post-emergence herbicides were assessed against the farmers' practice of hand weeding only. The experiment was laid out in Randomized Block Design (RBD) with eight replicates. The major weeds in the experimental fields were Cynodon dactylon, Digitaria ciliaris, Setaria glauca, Cyperus rotundus, Cyperus iria, Ageratum conyzoides, Ludwigia parviflora, Polygonum persicaria, etc. It was revealed that post emergence application of Quizalofop ethyl 5% @50 g a.i./ha at 15-20 DAS followed by one hand weeding produced significantly higher yield (33.90 q/ha) than farmers' practice (31.17 q/ha). The chemical treatment was found to be the most economic options (B: C ratio 2.79) against straw mulch treated plots (B: C ratio 2.55) and farmers' practice (B:C ratio 2.04). However, no significant difference in yield was achieved under chemical treated plots and mulched plots.

Management of Sheath Blight of Rice using Local Trichoderma Isolates of the Old Alluvial Zone of North Bengal

Goutam Mondal

Regional Research Station (Old Alluvial Zone), Uttar Banga Krishi Viswavidyalaya, Majhian, Patiram-733133, Dakshin Dinajpur, WB, India. Email: gm_rrsubkv@yahoo.co.in

Sheath blight of rice caused by Rhizoctonia solani Kühn is one of the major constraints for rice cultivation in old alluvial zone of North Bengal causing 5-70% loss in every year. Five biocontrol agents of Trichoderma spp. were isolated from this agro ecological zone and were identified after dual culture test against R. solani. A talc based bioformulation of Trichoderma spp. was prepared with

8 3x10 cfu to use in a field experiment. The experimental field was designed as split plot, divided into two blocks for each of 3 replications and one block of each replication was green manured with Dhaincha [Sesbania aculeata (Willd.)Pers]. Germinated seed and seedling of rice (cv. Swarna) were treated with the bioformulation @5g/l of water. For soil application, bioformulation @7.5kg/ha was mixed in soil at the time of final land preparation. Two commonly used fungicides, namely, Hexaconazol 5EC @2.0ml/l and Carbendazim 50WP @1ml/l were taken as check along with another check plot where no treatment was given. In the field experiment, all the bioformulations of Trichoderma spp. were found effective to increase the yield (12.50% to 23.14%) significantly over check plots and the isolate, Trichoderma sp. B18 was given the highest yield. Again, the efficacy of the biocontrol agents was significantly greater in the blocks with green manured than the blocks without green manured. The incidence disease was significantly reduced with 46.32% to 70.54% on application of bioagent and two fungicides, Hexaconazol 5EC and Carbendazim 50WP comparing with the check plot. It was also observed that the all biocontrol agents were found significantly effective than the fungicides, where the Trichoderma sp. B18 and Trichoderma sp. B16 was performed better in disease reduction. Therefore, the fungal biocontrol agents could be used as biofungicides for the management of sheath blight of rice as well as biofertilizer.

Analysis of Core Coat Protein Gene Sequences Associated with Yellow Vein Mosaic Diseases of Weed Species in North-East Indian Plains

Prosenjit Chakraborty, Bikram Saha, Dipanwita 1 *Saha , Aniruddha Saha

J Mycol Plant Pathol, Vol. 42, No.4, 2012542 J Mycol Plant Pathol, Vol. 42, No.4, 2012 543

Department of Botany, University of North Bengal, India, Pin- 734013, 1Department of Biotechnology, University of North Bengal, India, Pin- 734013. E-mail: asahanbu@yahoo.co.in

Croton bonplandianum Baill., Acalypha indica L. and Ageratum conyzoides L. are the common weeds, grown in and around the cultivated fields of sub-Himalayan north-east Indian plains. Yellow vein mosaic diseases caused by begomoviruses are often associated with the weeds and may act as reservoirs of crop infecting begomoviruses. To find correlation of the weed infecting begomoviruses with crop infecting begomoviruses the present study was under taken. The core coat protein gene sequences are known to be useful in Begomovirus classification and provisional identification of the begomoviruses. Cloning and sequencing of the core CP gene of the three infected samples (C. bonplandianum, A. indica and A. conyzoides) were done using two universal primer sets (AV494 and AC1048) to partially characterize the Begomovirus complexes associated with these weed species from sub-Himalayan north-east India plains. Core CP genes were found to be amplified from all the naturally infecting weed samples tested. Sequence analysis study and phylogenetic analysis of the present Begomovirus complexes revealed significant variation among their sequences, although causing the same yellow vein mosaic diseases and also exhibited closeness to weed infecting and crop infecting begomoviruses.

Molecular Detection and Identification of Potyviruses Infecting Papaya and Potato Growing in North-East Indian Plains

Shibu Das, Bikram Saha, Piyali Sarkar, Dipanwita 1 *Saha and Aniruddha Saha

Department of Botany, University of North Bengal, India, Pin- 734013, 1Department of Biotechnology, University of North Bengal, India, Pin- 734013. E-mail: asahanbu@yahoo.co.in

Papaya and potato are extensively cultivated vegetable crops in India. A severe mosaic disease of papaya and potato with significant disease incidence was observed during the survey of different areas of north-east Indian plains. Infected papaya plants showed mosaic and string formation in leaves, pale oily greasy streaks on stems and ring spots on the fruits. Foliar mosaic and stunting of plants was observed in case of potato plants. cDNA was prepared from the RNA extracted from papaya and potato leaves. Potyvirus primers (CP9502 and CPUP) were used to amplify the virus genome in PCR. A positive PCR amplification product is obtained from all the samples tested. PCR amplicons were cloned and sequenced (GenBank accession no. JX 567310 for papaya and JX945850 for potato). The sequence data analysis of papaya revealed highest 92% nucleotide sequence identity with Papaya ring spot virus type P (PRSV-P) and potato samples showed highest 99% nucleotide sequence identity with Potato virus Y (PV-Y). The phylogenetic analysis also showed closest relationship of the isolates having accession nos JX 567310 and JX945850 with various variants of PRSV and PVY respectively. On the basis of highest nucleotide sequence identity and closest relationships with PRSV and PVY, the virus isolates were considered as potyviruses.

Role of Biochemical and Nutritional Parameters of Piper betle L. Leaf in the Resistance to White Fly Species Singhiella pallida Singh

T Dhar, PM Bhattacharya* and SK Senapati

Department of Agricultural Entomology and Plant Pathology*, Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar, West Bengal

Betelvine (Piper betle L.) is a perennial, dioecious evergreen creeper, grown in shady condition with warm and humid climate under conservatory. It is an important cash crop of rural India, which has immense potentiality in medicinal industry due to presence of wide array of primary and secondary plant metabolites in its leaf. White fly, Singhiella pallida Singh (Aleyrodidae: Hemiptera) is an important pest, found infesting the crop for the presence of micro-climate within the conservatory throughout the year, thus causing huge crop loss. Screening of betelvine cultivars for its resistance to S. pallida was carried out at the Research Farm of Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar, and West Bengal, India in the consecutive two years 2009-2010. Emphasis was given to find out the possible reasons of differential feeding preference of the pest by bio-chemical analysis of the betel leaf. Nine 'Bangla type cultivars and two 'Sanchi' type cultivars were used for screening to elucidate their resistance against the white fly, both Sanchi type cultivars viz. Simurali Sanchi and Halisahar Sanchi showed high resistance against the pest throughout the period of investigation. However, Simurali Sanchi was revealed more resistant than Halisahar Sanchi. In contrary, 'Bangla' type variety Simurali Golebhavna was noticed as most susceptible cultivar. Two 'Bangla' type cultivars namely Bagehot Local and Simurali Havana exhibited moderate resistance to white fly, while rest six 'Bangla' type cultivars were highly or moderately susceptible to the pest. Most of the biochemical and nutritional parameters had an important role in fluctuation of the white fly population. Phenol, ortho-dihydroxy (OD) phenol, polyphenol (PPO) and peroxidase (POD) activities in leaves were inversely correlated with the white fly population, while a positive response was recorded to leaf protein, nitrogen and phosphorus. Both the resistant varieties contained higher amount of phenol and OD phenol content as well as higher PPO and POD activities, resulting in low level of the white fly infestation. However, high protein, nitrogen concentration, nitrogen and phosphorus content in unit area of leaf were noticed in the susceptible cultivars, which induced high level infestation of the white fly. So far as cumulative role of the biochemical and nutritional parameters when taken into consideration, PPO and OD phenol have been identified most important factors in population fluctuation of the white fly; contributing 96.9% of total variation among the populations.

Turcicum Leaf Blight of Maize: Occurrence and Management under North Bengal Situation

Sajeed Ali and AK Chowdhury

Department of Plant Pathology, Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar, 736 165, West Bengal

Maize (Zea mays L.) is a miracle C4 cereal crop belonging to graminaceous family. It and has a very high yield potential and grown throughout the world from temperate to tropic regions. In West Bengal, Maize is cultivated both in Darjeeling Hills and Terai Zone of West Bengal; in hills it is cultivated as rabi crop. Farmers start sowing of seeds from mid of February to mid of March as rainfed crop, the growing period coincides with monsoon and hot summers which makes plant more liable to different diseases. There are numerous foliar blights diseases reported on maize, among them Turcicum Leaf Blight (TLB) disease caused by Exerohilum turcicum is important because yield losses as high as 60 % have been reported on susceptible cultivar. The pathogen is

J Mycol Plant Pathol, Vol. 42, No.4, 2012544

capable of infecting in all the stages from seedlings to maturity. The symptoms starts appearing form seedling to maturing stage; the first symptom appeared as a small oval spots, usually gray in colour on the lower leaves and spreads upwards. Slowly this spot enlarged and appeared as spindle shaped with pointed ends having gray centre and dark brown margin. The conidia are borne on the tip of conidiophores of the pathogen; the conidia are light brown to dark brown in colour. Conidiophores of the pathogen emerged out from the stomata in a bunch. Morphological and molecular characterizations of nine isolates of the E. turcicum have been carried out. An integrated disease management has been developed against the disease and seed treatment with Captan followed by three foliar sprays of Propiconazole is found to be the most effective in reducing the disease severity and increasing the yield.

Effect of Seed Encapsulation with Trichoderma harzianum on Growth Promotion and Development of Induced Biochemical Resistance in Cauliflower Seedling.

Tshering Lama, A Roy and PM Bhattacharya

Department of Plant Pathology, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, 736 165, West Bengal. E mail: amalgniretsh@rediffmail.com

The formulation of microbial biomass represents a critical step in

advancing the commercial development of prospective biological

control agents and enhances their bio-control potential. An

investigation was conducted to study the effect of seed

encapsulation with Trichoderma harzianum on growth promotion

and systemic induction of biochemical resistance in cauliflower

seedling. Type of formulations included carrier based preparations

viz., talc and activated charcoal and the others were alginate pellet

formulations, with calcium chloride (CaCl ) and calcium gluconate 2

(C H CaO ) as gellant. These formulations were applied through 12 22 14

three different delivery systems viz., soil application, seed pelleting

and seed dressing under protected seedling raising system in

portrays. The germination behaviour was recorded during the

seedling growing period, whereas, physical and biochemical

studies were conducted with the seedlings of transplanting stage.

The germination percentage at transplanting stage showed that

pellet based formulation had pronounced effect (1.67-1.85 fold

increase) on seed germination than carrier based formulation (1.63-

1.74 fold increase). Soil application of CaCl based pellets had 2

highest potential in increasing germination index and germination

rate of cauliflower seedling. Seed dressing with talc based

formulation recorded highest chlorophyll content. Vigour index in

bioinoculated treatments was significantly at par and only differed

with non treated control yet seed dressing with activated charcoal

based formulation had shown comparatively better vigour index

(1350.56). Biochemical studies of cauliflower seedlings showed

that protein content in the bio-inoculated treatments did not

differed significantly only differed from non treated control.

Phenol and OD phenol concentration was significantly high

enough when soil application of C H CaO gelled alginate pellet 12 22 14

-1 formulation was done (1.998 and 0.32 mg g fresh wt.,

respectively). Peroxidase activity was found to be highest in case

of seed pelleting using C H CaO as gelling agent (Ä 18.33 at 12 22 14

-1 -1490nm min g fresh wt) while poly phenol oxidase activity was

highest in seed dressing with talc formulation (Ä 6.95 at 495nm

-1 -1min g fresh wt). Highest soil dehydrogrenase activity was

measured in seed dressing with activated charcoal based

formulation which was statistically at par with seed dressing with

talc formulation and soil application of C H CaO gelled alginate 12 22 14

pellet formulation. From the present investigation it is concluded

that seed dressed with T. harzianum by using calcium gluconate as

gelling agent is an effective delivery approach of the bioagent for

improvement of seedling vigour along with development of

induced resistance in the cauliflower seedlings.

Management of Soft Rot and Bacterial Wilt

Disease of Ginger with Special Reference to

Cabbage Biofumigation

1 2S Bandyopadhyay and S Khalko

1 2AICRP on Spices, Department of Plant Pathology, Uttar Banga Krishi

Viswavidyalaya, Pundibari, Coochbehar – 736165, West Bengal. E

mail: bandyopadhyaysekhar@yahoo.co.in

India ranks first in the production (2, 73,333 tonnes) and second in

the area (80,000 ha) of ginger in the world. In India the major

Ginger producing states are Kerala, Orissa, Andhra Pradesh,

Himachal Pradesh, Meghalaya and West Bengal. The productivity

of ginger in West Bengal is low (10.30 t/ha) as compared to the

highest productivity (18.75 t/ha) in Tamil Nadu. The productivity

of ginger varies between 1t/ha to 14 t/ha in different districts of

West Bengal. Productivity is low in the plains of the state. This is

due to different factors, one of the factors being the attack of

different soil borne diseases mainly soft rot and bacterial wilt

disease of ginger. Keeping in mind of the above, a novel approach

like cabbage bio-fumigation was used along with 5 other

treatments for the management of those 2 diseases during 2009 –

2011 ginger growing seasons. In pooled data analysis for the 3

years, it was found that biofumigation using cabbage is the best

treatment as it produced the lowest bacterial wilt (6.02%

incidence) and soft rot (10.05% incidence) disease incidence of

ginger. This treatment is closely followed by soil treatment by

bleaching powder @ 10g/bed (3m × 1m) which recorded 8.24%

bacterial wilt and 12.79% soft rot disease incidence. These 2

treatments produced yield of 16.31 t/ha and 14.90 t/ha respectively.

Regarding leaf spot disease incidence, minimum PDI of 12.54 and

maximum PDI of 16.95 was recorded in cabbage bio-fumigation

treatment and soil treatment by bleaching powder respectively.

Biology of Mango Defoliator, Cricula sp. in

North Bengal Conditions

J Ghosh and N Chaudhuri*

Dept. of Agril. Entomology, Uttar Banga Krishi Viswavidyalaya,

Pundibari, Coochbehar.

RRS, Terai Zone, Uttar Banga Krishi Viswavidyalaya, Pundibari,

Coochbehar.

The biology of Cricula sp. was studied on mango leaves under laboratory condition at the Department of Agril. Entomology, Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar. Studies were made in two different seasons i.e., one during March to June and another during June to October. Performance of biology was found better in first season. Different aspects of biology namely,

st nd rd th th thincubation period, duration of 1 , 2 , 3 , 4 , 5 and 6 instars of

J Mycol Plant Pathol, Vol. 42, No.4, 2012 545

larvae; duration of pre-pupal and pupal stage; duration of male and female; length, breadth and weight of corresponding instars, pupal stage and adult stage were studied. The result indicated that the average incubation period was 10.8 and 10.4 days respectively in two seasons. Total larval duration was more or less similar; 36.4days in March-June and 37.8 days in June-October season. Pupal diapauses were found of 99.51 days in June-October. In both the season adult male lived shorter than adult female. Total life span of male (64.94 days) was shorter than female (66.29 days) in March-June season while in June-October season the total life span is prolonged in male (140.61days) and female (141.91days).

Food Utilization Efficiencies of Mango Defoliator Cricula sp. in Terai Region of West Bengal

N Chaudhuri* and J Ghosh

Dept. of Agril. Entomology, Uttar Banga Krishi Viswavidyalaya, Pundibari, CoochbeharRRS, Terai Zone, Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar

The experiment was carried out to study the nutritional efficiency of mango defoliator Cricula sp. in two important seasons (May-June and October-November) in terai region of West Bengal. In order to have a detailed picture of food utilization daily measurement of dry matter ingested, faeces produced and biomass gain by the larva were recorded. Consumption rate was increased

thwith the age and reached highest value in the 6 instars during thMay-June while it was highest in 5 instars during October-

November. The percent biomass gain also increased with the advancement of larval development. The larva ingested over 60% of their total intake during last instars. The ability to digest food decreased gradually to the late stage larvae since they become a voracious feeder and intake crude fiber that affects the digestibility. The efficiency percent of conversion of food ingested and digested varied significantly in different instars and the value was higher during October-November.

Seasonal Incidence of Insect-Pests of Okra under Terai Region of West Bengal

Dipen Dahal

Department of Agricultural Entomology,Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar 736 165, West Bengal

Field studies were carried out at the farm of Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar during 2011-12 to find out the seasonal incidence against insect-pests of okra in two seasons i.e., rabi and Kharif. Different insects-pests of okra namely, jassid (Amrasca biguttula biguttula Ishida), aphid (Aphis gossypii, Glover), leaf roller (Sylepta derogate Fabr.), epilachna beetle (Henisepilachna vigintioctopunctata), flea beetle (Phyllotreta sp.) and fruit borer (Earias insulana Boisd. and E. vittella Fabr.) were found to occur in this region. The magnitude of infestation was found higher in Rabi season than Kharif season. Peak population of jassid, aphid, leaf roller, epilachna beetle, flea beetle and fruit

th th thborer was observed at 46 standard week, 50 standard week, 46 th th thstandard week, 47 standard week, 47 standard week and 49

thstandard week respectively in rabi season while at 26 standard th th thweek, 30 standard week, 27 standard week, 28 standard week,

th th26 standard week and 30 standard week respectively in Kharif season.

Effect of Bio-Ferti l izers and Organic Amendments on Yield and Disease Management of Betelvine (Piper betle L.) under Problematic Terai Soils of West Bengal.

1* 2 3PS Medda , S Chakraborty , PM Bhattacharya1Department of Plantation Crops & Processing, Faculty of

3Horticulture, Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, 736 165,

2West Bengal Department of Crop Improvement, Horticulture & Agricultural Botany, Palli Siksha Bhavana, Visva-Bharati, Santiniketan, Birbhum, E-mail : psmedda@gmail.com

Betel leaves are consumed raw; it needs to be free from toxic chemicals accumulated through non-judicious application of chemical fertilizers and pesticides. Hence, management practices needs to be reframed for the multiple nutrient deficient terai soils, using organic amendments, bio-fertilizers and bio-pesticides to improve the yield, quality of leaves and management of serious diseases.

A field experiment was conducted for two consecutive years (2008 and 2009) in a betelvine (cv. Kali Bangla) plantation in split-plot Design replicated three times in the instructional Farm of Uttar Banga Krishi Viswavidyalaya, Coochbehar with a strategy to manage the betelvine leaf and vine diseases, based on the principle of avoidance of disease following integrated nutrient management through reduction in application of inorganic nitrogenous fertilizer. A uniform plot size of 2 x 1 m with paired rows consisting of 40 vines for each of the treatment was maintained. The 50% of the nitrogen nutrition was supplemented with organic and in-organic sources as mustard cake and urea respectively as main plot treatments and rest 50% was applied through different sub-plot treatments containing various bio-fertilizers and organic amendments in eight equal splits at 30 days interval starting March, 2008. Potash and phosphate requirement was fulfilled at a time along with 10 tonnes of FYM/ha at the onset of active growing season (March).

Results revealed that in the Terai region of West Bengal combined application of PSB and VAM with full N and K O along with no or 2

partial phosphate nutrition gave higher leaf production per month as well as higher yield with increased leaf size compared to other treatments. The results indicated the role of phosphate solubilizers and phosphate mobilisers in phosphate locking acid soils of the candidate environment under study. Application of Trichoderma and Pseudomonas fluorescence showed moderate to high tolerance to Bacterial leaf spot and foot rot under organic system.

Study on the Shelf Life of the Trichoderma Isolate in Talc, Prills, Vermicompost, Sago and Dalia Based Formulation

1 1Anamika Debnath, A Roy and PM Bhattacharya1Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Kishi Viswavidyalaya, Pundibari, Cooch Behar, 736165, West Bengal

For making biocontrol product stable, effective, safer and obviously economic in case of storage and field level applications; biocontrol agent should be formulated properly. Formulation of biocontrol agent can be done in different forms. Several workers reported that amendments like chitin and ammonium sulphate

J Mycol Plant Pathol, Vol. 42, No.4, 2012544

capable of infecting in all the stages from seedlings to maturity. The symptoms starts appearing form seedling to maturing stage; the first symptom appeared as a small oval spots, usually gray in colour on the lower leaves and spreads upwards. Slowly this spot enlarged and appeared as spindle shaped with pointed ends having gray centre and dark brown margin. The conidia are borne on the tip of conidiophores of the pathogen; the conidia are light brown to dark brown in colour. Conidiophores of the pathogen emerged out from the stomata in a bunch. Morphological and molecular characterizations of nine isolates of the E. turcicum have been carried out. An integrated disease management has been developed against the disease and seed treatment with Captan followed by three foliar sprays of Propiconazole is found to be the most effective in reducing the disease severity and increasing the yield.

Effect of Seed Encapsulation with Trichoderma harzianum on Growth Promotion and Development of Induced Biochemical Resistance in Cauliflower Seedling.

Tshering Lama, A Roy and PM Bhattacharya

Department of Plant Pathology, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, 736 165, West Bengal. E mail: amalgniretsh@rediffmail.com

The formulation of microbial biomass represents a critical step in

advancing the commercial development of prospective biological

control agents and enhances their bio-control potential. An

investigation was conducted to study the effect of seed

encapsulation with Trichoderma harzianum on growth promotion

and systemic induction of biochemical resistance in cauliflower

seedling. Type of formulations included carrier based preparations

viz., talc and activated charcoal and the others were alginate pellet

formulations, with calcium chloride (CaCl ) and calcium gluconate 2

(C H CaO ) as gellant. These formulations were applied through 12 22 14

three different delivery systems viz., soil application, seed pelleting

and seed dressing under protected seedling raising system in

portrays. The germination behaviour was recorded during the

seedling growing period, whereas, physical and biochemical

studies were conducted with the seedlings of transplanting stage.

The germination percentage at transplanting stage showed that

pellet based formulation had pronounced effect (1.67-1.85 fold

increase) on seed germination than carrier based formulation (1.63-

1.74 fold increase). Soil application of CaCl based pellets had 2

highest potential in increasing germination index and germination

rate of cauliflower seedling. Seed dressing with talc based

formulation recorded highest chlorophyll content. Vigour index in

bioinoculated treatments was significantly at par and only differed

with non treated control yet seed dressing with activated charcoal

based formulation had shown comparatively better vigour index

(1350.56). Biochemical studies of cauliflower seedlings showed

that protein content in the bio-inoculated treatments did not

differed significantly only differed from non treated control.

Phenol and OD phenol concentration was significantly high

enough when soil application of C H CaO gelled alginate pellet 12 22 14

-1 formulation was done (1.998 and 0.32 mg g fresh wt.,

respectively). Peroxidase activity was found to be highest in case

of seed pelleting using C H CaO as gelling agent (Ä 18.33 at 12 22 14

-1 -1490nm min g fresh wt) while poly phenol oxidase activity was

highest in seed dressing with talc formulation (Ä 6.95 at 495nm

-1 -1min g fresh wt). Highest soil dehydrogrenase activity was

measured in seed dressing with activated charcoal based

formulation which was statistically at par with seed dressing with

talc formulation and soil application of C H CaO gelled alginate 12 22 14

pellet formulation. From the present investigation it is concluded

that seed dressed with T. harzianum by using calcium gluconate as

gelling agent is an effective delivery approach of the bioagent for

improvement of seedling vigour along with development of

induced resistance in the cauliflower seedlings.

Management of Soft Rot and Bacterial Wilt

Disease of Ginger with Special Reference to

Cabbage Biofumigation

1 2S Bandyopadhyay and S Khalko

1 2AICRP on Spices, Department of Plant Pathology, Uttar Banga Krishi

Viswavidyalaya, Pundibari, Coochbehar – 736165, West Bengal. E

mail: bandyopadhyaysekhar@yahoo.co.in

India ranks first in the production (2, 73,333 tonnes) and second in

the area (80,000 ha) of ginger in the world. In India the major

Ginger producing states are Kerala, Orissa, Andhra Pradesh,

Himachal Pradesh, Meghalaya and West Bengal. The productivity

of ginger in West Bengal is low (10.30 t/ha) as compared to the

highest productivity (18.75 t/ha) in Tamil Nadu. The productivity

of ginger varies between 1t/ha to 14 t/ha in different districts of

West Bengal. Productivity is low in the plains of the state. This is

due to different factors, one of the factors being the attack of

different soil borne diseases mainly soft rot and bacterial wilt

disease of ginger. Keeping in mind of the above, a novel approach

like cabbage bio-fumigation was used along with 5 other

treatments for the management of those 2 diseases during 2009 –

2011 ginger growing seasons. In pooled data analysis for the 3

years, it was found that biofumigation using cabbage is the best

treatment as it produced the lowest bacterial wilt (6.02%

incidence) and soft rot (10.05% incidence) disease incidence of

ginger. This treatment is closely followed by soil treatment by

bleaching powder @ 10g/bed (3m × 1m) which recorded 8.24%

bacterial wilt and 12.79% soft rot disease incidence. These 2

treatments produced yield of 16.31 t/ha and 14.90 t/ha respectively.

Regarding leaf spot disease incidence, minimum PDI of 12.54 and

maximum PDI of 16.95 was recorded in cabbage bio-fumigation

treatment and soil treatment by bleaching powder respectively.

Biology of Mango Defoliator, Cricula sp. in

North Bengal Conditions

J Ghosh and N Chaudhuri*

Dept. of Agril. Entomology, Uttar Banga Krishi Viswavidyalaya,

Pundibari, Coochbehar.

RRS, Terai Zone, Uttar Banga Krishi Viswavidyalaya, Pundibari,

Coochbehar.

The biology of Cricula sp. was studied on mango leaves under laboratory condition at the Department of Agril. Entomology, Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar. Studies were made in two different seasons i.e., one during March to June and another during June to October. Performance of biology was found better in first season. Different aspects of biology namely,

st nd rd th th thincubation period, duration of 1 , 2 , 3 , 4 , 5 and 6 instars of

J Mycol Plant Pathol, Vol. 42, No.4, 2012 545

larvae; duration of pre-pupal and pupal stage; duration of male and female; length, breadth and weight of corresponding instars, pupal stage and adult stage were studied. The result indicated that the average incubation period was 10.8 and 10.4 days respectively in two seasons. Total larval duration was more or less similar; 36.4days in March-June and 37.8 days in June-October season. Pupal diapauses were found of 99.51 days in June-October. In both the season adult male lived shorter than adult female. Total life span of male (64.94 days) was shorter than female (66.29 days) in March-June season while in June-October season the total life span is prolonged in male (140.61days) and female (141.91days).

Food Utilization Efficiencies of Mango Defoliator Cricula sp. in Terai Region of West Bengal

N Chaudhuri* and J Ghosh

Dept. of Agril. Entomology, Uttar Banga Krishi Viswavidyalaya, Pundibari, CoochbeharRRS, Terai Zone, Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar

The experiment was carried out to study the nutritional efficiency of mango defoliator Cricula sp. in two important seasons (May-June and October-November) in terai region of West Bengal. In order to have a detailed picture of food utilization daily measurement of dry matter ingested, faeces produced and biomass gain by the larva were recorded. Consumption rate was increased

thwith the age and reached highest value in the 6 instars during thMay-June while it was highest in 5 instars during October-

November. The percent biomass gain also increased with the advancement of larval development. The larva ingested over 60% of their total intake during last instars. The ability to digest food decreased gradually to the late stage larvae since they become a voracious feeder and intake crude fiber that affects the digestibility. The efficiency percent of conversion of food ingested and digested varied significantly in different instars and the value was higher during October-November.

Seasonal Incidence of Insect-Pests of Okra under Terai Region of West Bengal

Dipen Dahal

Department of Agricultural Entomology,Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar 736 165, West Bengal

Field studies were carried out at the farm of Uttar Banga Krishi Viswavidyalaya, Pundibari, Coochbehar during 2011-12 to find out the seasonal incidence against insect-pests of okra in two seasons i.e., rabi and Kharif. Different insects-pests of okra namely, jassid (Amrasca biguttula biguttula Ishida), aphid (Aphis gossypii, Glover), leaf roller (Sylepta derogate Fabr.), epilachna beetle (Henisepilachna vigintioctopunctata), flea beetle (Phyllotreta sp.) and fruit borer (Earias insulana Boisd. and E. vittella Fabr.) were found to occur in this region. The magnitude of infestation was found higher in Rabi season than Kharif season. Peak population of jassid, aphid, leaf roller, epilachna beetle, flea beetle and fruit

th th thborer was observed at 46 standard week, 50 standard week, 46 th th thstandard week, 47 standard week, 47 standard week and 49

thstandard week respectively in rabi season while at 26 standard th th thweek, 30 standard week, 27 standard week, 28 standard week,

th th26 standard week and 30 standard week respectively in Kharif season.

Effect of Bio-Ferti l izers and Organic Amendments on Yield and Disease Management of Betelvine (Piper betle L.) under Problematic Terai Soils of West Bengal.

1* 2 3PS Medda , S Chakraborty , PM Bhattacharya1Department of Plantation Crops & Processing, Faculty of

3Horticulture, Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, 736 165,

2West Bengal Department of Crop Improvement, Horticulture & Agricultural Botany, Palli Siksha Bhavana, Visva-Bharati, Santiniketan, Birbhum, E-mail : psmedda@gmail.com

Betel leaves are consumed raw; it needs to be free from toxic chemicals accumulated through non-judicious application of chemical fertilizers and pesticides. Hence, management practices needs to be reframed for the multiple nutrient deficient terai soils, using organic amendments, bio-fertilizers and bio-pesticides to improve the yield, quality of leaves and management of serious diseases.

A field experiment was conducted for two consecutive years (2008 and 2009) in a betelvine (cv. Kali Bangla) plantation in split-plot Design replicated three times in the instructional Farm of Uttar Banga Krishi Viswavidyalaya, Coochbehar with a strategy to manage the betelvine leaf and vine diseases, based on the principle of avoidance of disease following integrated nutrient management through reduction in application of inorganic nitrogenous fertilizer. A uniform plot size of 2 x 1 m with paired rows consisting of 40 vines for each of the treatment was maintained. The 50% of the nitrogen nutrition was supplemented with organic and in-organic sources as mustard cake and urea respectively as main plot treatments and rest 50% was applied through different sub-plot treatments containing various bio-fertilizers and organic amendments in eight equal splits at 30 days interval starting March, 2008. Potash and phosphate requirement was fulfilled at a time along with 10 tonnes of FYM/ha at the onset of active growing season (March).

Results revealed that in the Terai region of West Bengal combined application of PSB and VAM with full N and K O along with no or 2

partial phosphate nutrition gave higher leaf production per month as well as higher yield with increased leaf size compared to other treatments. The results indicated the role of phosphate solubilizers and phosphate mobilisers in phosphate locking acid soils of the candidate environment under study. Application of Trichoderma and Pseudomonas fluorescence showed moderate to high tolerance to Bacterial leaf spot and foot rot under organic system.

Study on the Shelf Life of the Trichoderma Isolate in Talc, Prills, Vermicompost, Sago and Dalia Based Formulation

1 1Anamika Debnath, A Roy and PM Bhattacharya1Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Kishi Viswavidyalaya, Pundibari, Cooch Behar, 736165, West Bengal

For making biocontrol product stable, effective, safer and obviously economic in case of storage and field level applications; biocontrol agent should be formulated properly. Formulation of biocontrol agent can be done in different forms. Several workers reported that amendments like chitin and ammonium sulphate

J Mycol Plant Pathol, Vol. 42, No.4, 2012546

increases the bioefficacy of Trichoderma isolate and shows positive effect on multiplication and storage of Trichoderma sp. An attempt was taken to formulate the Trichoderma sp. in form of talc, sago, dalia, and palates using bentonite and wheat flour. Ammonium sulphate (0.5% and 1%) and chitin (01%) was used to increase the storage life and multiplication of the Trichoderma sp. Sago and dalia proved to be a good substrate for the bioagent under study in comparison to the conventional substrate like talc. Among the amendments added in the growth media 1% chitin may be an effective supplement to the growth media for increasing its survival in storage. From the interaction studied between different substrates and different amendments selected for the shelf life study a combination of sago and 1 % chitin found to be efficient for multiplication of Trichoderma isolate. The rate of decline in population was found low for alginate prills both in bentonite and wheat. Rate of decline was higher in organic substrates such as vermicompost, sago and dalia. Rate of decline was observed lower in 0.5% ammonium sulfate and 1% chitin amendment than the control.

Combined Effect of Meteorological Factors on Leaf blight Progression and their Comparison between Two Growth Models (Logistic and Gompertz) for predicting Disease Severity on Mustard

1 2Sunita Mahapatra and Srikanta Das1AICW&BIP, Uttar Banga Krishi Viswavidyalaya, Pundibari,

2 Coochbehar, West Bengal 736 165. Department of Plant Pathology, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal 741252.

Step down multiple regression analysis were used to identify those meteorological parameters useful in explaining variation in severities of Alternaria leaf blight of mustard (Alternaria brassicae and Alternaria brassicicola). Disease severity estimates (Y), maximum temperature (T ), minimum temperature (T ), max min

maximum relative humidity(RH ), minimum relative humidity( max

RH ), total rainfall (RT), maximum wind velocity (WV ), min max

minimum wind velocity (WV ), maximum vapour pressure (VP min

), minimum vapour pressure (VP ), bright sunshine hour (BSH) max min

were used as variable. Different weather variables were influenced differently on disease severity at five different dates of sowing for the two consecutive years. Gompertz equation was best linearized with the disease progress data followed by logistic and untransformed data sets. The linear prediction equations are (1) Y=

th3.203 – 0.356 ( T )+ 0.015 (RH ) for 20 October sowing; (2) Y min min

th= - 1.929 + 1.634 (WV ) + 0.067 (RT) for 5 November sowing; min

(3) Y = - 121.91+ 1.57(T )+ 1.083(RH ) + 0.29(RH ) - min max min

2.27(VP ) - 0.61(VP ) – 17.17(WV ) + 17.83(WV ) max min max min

th+1.65(BSH) + 0.113(RT) for 20 November sowing; (4) Y = - th5.131 + 0.25 (VP )+ 0.256 (BSH)+ 0.057 (RT) for 5 December max

thsowing; (5) Y = - 3.19 + 0.235(T ) for 20 December sowing.min

Evaluation of Cucumber Germplasm Health against Downy Mildew Disease for their Value Added Utilization

MK Bag*, Pragya, A Roy and KK Gangopadhyay

Germplasm Evaluation Division, National Bureau of Plant Genetic Resources, New Delhi 110012, India. E-mail: manas.bag@gmail.com

Conservation of healthy germplasm is important for successful crop improvement programme. Cucumber (Cucumis sativus L.) is one of the most important indigenous vegetables consumed throughout the world in salad, cooked and pickle form. Cucumber is often regarded as health foodof its low calorie content and presence of vitamins and minerals. Cucumber is highly susceptible to a range of diseases and pests which hinders its commercial production. Cucumber is known to be the most preferred host for almost all types of viruses affecting Cucurbitaceous crops. Despite the presence of vast genetic diversity throughout the country, the Indian cucumber germplasm has not been fully exploited for identification of useful source of resistance to various biotic and abiotic stresses as well as its status regarding resistant against downy mildew disease. Downy mildew, a foliar disease caused by Pseudoperonospora cubensis (Berk. and Curt.) Rostov. is one of the most destructive diseases of cucumber. Moderately resistant cultivars are available, but yield losses are high without the use of fungicides. With the objective to identify resistant source for downy mildew disease, a total of 88 accessions of cucumber collected from different parts of India were screened during Kharif 2012 at NBPGR farm, New Delhi. Percent disease severity was observed 100 in case of 9 accessions. Pusa Uday and Pusa Harit are two varieties taken as check variety has shown 100% disease severity. 40 to 80 percent disease severity was observed in 59 accessions. Out of 88 accessions, 7 accessions were found promising because severity was less than 10%. Promising accessions are IC527394, IC527397, IC527400, IC527404, IC527405, IC527423 and EC738032. These promising germplasm could be utilized for evolving disease resistant varieties with desirable quality traits.

Biochemical Variation of Some Alternaria species Infected on Different Floricultural Plants

1BS Ambesh* and Srikanta Das

Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Krishi, Viswavidyalaya, Pundibari, Cooch Behar 736 165, W.B1Department of Plant Pathology, Faculty of Agriculture, Bidhan Chandra Krishi, Viswavidyalaya, Mohanpur, Nadia-741252, West Bengal, Email: bharatambesh@gmail.com

Alternaria spp. is an economically important pathogen widely distributed throughout the world and cause devastated disease on tuberose, marigold, rose, gladiolus and other floricultural crops. Isozyme analysis revealed considerable diversity among isolates of Alternaria spp. The isozyme tested in native polyacrylamide gel electrophoresis (PAGE), â- esterase produced well resolved electrophoretic phenotypes that could be used as markers for the isolates. Isozyme pattern particularly â- esterase produces different bands with different Rm value. Clustering analysis of these isozyme profiles showed two clusters among the four isolates. In the first cluster, tuberose and rose isolates were grouped together and in second cluster, gladiolus and marigold isolates. Though tuberose, gladiolus, marigold and rose isolates produces different amount of phenol and carbohydrate. So, it can be concluded from this study that Alternaria spp. of four host cultivars exists high isozyme variability among themselves.

Ecofriendly Management of Yellow Mosaic Virus of Mungbean by using Botanical Oils

1Dharnendra Reang* and PS Nath

J Mycol Plant Pathol, Vol. 42, No.4, 2012 547

Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal 736 165.Department of Plant Pathology, Faculty of Agriculture, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia-741252, West Bengal, Email: danenreang@gmail.com

Mungbean or green gram, scientifically known as Vigna radiata L. Wilczek, is one of the important short duration pulse crops of Indian origin. In West Bengal, mungbean is the principle pulse crop and mainly grown in Pre-Kharif and Kharif season. Mungbean is known to be affected by several diseases, incited by viruses, fungi, bacteria and nematodes. Of the various viral diseases Yellow Mosaic is widely distributed and most destructive. Considering the immense economic significance of 'Mungbean Yellow Virus disease' Investigations are being carried out both at the national and international levels of different aspects of this disease particularly on the management by means of, suitable tolerant varieties, control of it insect vector (Bemisia tabaci Genn.) by using botanicals oils. But spraying of chemical insecticides possesses a threat to environment and health hazard. So, considering this fact, experiment was conducted to control the disease by alternative methods like spraying of eco friendly botanical oils and to search tolerant varieties. Among the five plant origin oil products with different doses were tested for spraying, Neem@ 0.2% showed lowest incidence (10.49%) and severity (9.58%) and the percentage of disease control was 77.94 and 77.55 respectively. Significant highest yield (1.78 kg/plots) was also recorded in Neem@ 0.2% sprayed plots. The population of whitefly was low in Neem oil@0.2% treated plots (2.25 per plants). So, Neem oil@ 0.2% is recommended for the control of the disease in the plains of West Bengal.

Refocusing the Plant Disease Pattern under Changing Climate Scenario

1 2 3K Pradhan , Soma Biswas and S Biswas1 Assistant Professor, Department of Agricultural Extension, UBKV,

2.Pundibari, Coochbehar. Subject Matter Specialist (Agricultural 3.Extension), Coochbehar KVK, UBKV, Pundibari, Coochbeha. Subject

Matter Specialist (Soil Science), Coochbehar KVK, UBKV, Pundibari, Coochbehar

Under changed climate scenario, the dynamics of the plant disease pattern is gaining a momentum for huge crop loss vis a vis loss of earning in the rural areas. The disease complex in case of crops cultivated is very much situation specific and demands a special consideration to solve the problem in field situation. The interrelated climate, land, water, vegetation and human activity determine the ever changing environment on the earth. The apparent plasticity of some agricultural systems may help to minimize negative impacts of climate change through the adoption of new adapted cultivars and other practices. However, despite significant improvements in technology, diseases continue to impose significant constraints to production under the current climate. Disease may further restrict the limited range of crops or cultivars that are adapted to a changing climate. The emerging body of knowledge strongly suggests that climate change, especially changes in precipitation, events environment and atmospheric composition will significantly add to the complex interaction between technological and socio-economic changes in influencing plant diseases. In future the potential impacts of climate change would be observed in three areas a) changes in crop loss due to diseases, b) effectiveness of management strategies and

c) geographical distribution of diseases. In such a research climate, a study was conducted with an aim to refocus the existing plant disease pattern in the district of Coochbehar, West Bengal under the changed climate perspective. Three villages at Coochbehar-II block in Coochbehar district were selected purposively. The data were collected with the help of semi structured interview schedule through focus group discussion method. Each focus group contains fifteen respondents. The data were collated and interpreted to find out the existing plant disease pattern in the study area and analyze the socio-economic and socio-personal characters of the respondents related with the study.

Stress Induced Antioxidant Enzyme Activity Contributes to Water Deficit Stress Tolerance in Groundnut (Arachis hypogaea L.)

K Chakraborty*, KA Kalariya, Nisha Goswami and AL Singh

Directorate of Groundnut Research, Ivnagar Road, P.B. No. 5, Junagadh – 362 001, Gujarat

Groundnut is an important oilseed which is mostly grown under rain-fed condition in various parts of India. Because of changing climatic scenario and erratic rainfall pattern it quite often faces severe water-deficit stress during the crop season. Hence, a field experiment was conducted with six Spanish cultivars viz. 'SG 99', 'ICGS 44', 'ICGV 86031', 'TAG 24', 'AK 159' and 'DRG 1' during summer 2011 to study the characters of oxidative stress tolerance and activities of antioxidant enzymes under water-deficit condition. Stress was imposed by withholding irrigation from 31 to 62 DAS and then again from 62 to 87 DAS, during flowering (WS 1) and pod development stages (WS 2) respectively. Although in WS 1 the total chlorophyll content increased in all the cultivars except 'SG 99', but in WS 2 it reduced in all the cultivars ranging from 5.5% ('ICGS 44') to 16.2% ('DRG 1'). Membrane stability index (MSI) decreased under water-deficit stress in both flowering and pod development stage and the reduction was highest in 'DRG 1' (22.1%) in pod development stage compared to that of non-stressed plants. Production of reactive oxygen species in terms of H O and superoxide radical (SOR), and lipid peroxidation was 2 2

more at both flowering and pod development stages with highest SOR content in 'ICGV 86031' and 'DRG 1'. Similarly, H O content 2 2

in 'ICGV 86031' increased in both WS 1 and WS 2. The result showed that 'ICGS 44' and 'TAG 24' had high recovery capacity with least H O production during the stress relief. Activity of the 2 2

antioxidant enzymes viz. superoxide dismutase was high especially during pod development stage in 'ICGS 44' and 'TAG 24'. Similarly, the activities of other enzymes like catalase, peroxidase, glutathione reductase and ascorbate peroxidase showed increase under water-deficit stress. Compared to other cultivars, 'ICGS 44' and 'TAG 24' showed better tolerance capacity by maintaining higher relative water content and antioxidant enzyme activity, and sustaining much less membrane injury due to imposition of water-deficit stress.

Expression Analysis of the Zinc Transporter (Zip) Gene Family and its Application as Marker to Identify the High Kernel Zn Content in Maize (Zea mays)

Tapan Kumar Mondal* and Showkat Ahemd Genei

J Mycol Plant Pathol, Vol. 42, No.4, 2012546

increases the bioefficacy of Trichoderma isolate and shows positive effect on multiplication and storage of Trichoderma sp. An attempt was taken to formulate the Trichoderma sp. in form of talc, sago, dalia, and palates using bentonite and wheat flour. Ammonium sulphate (0.5% and 1%) and chitin (01%) was used to increase the storage life and multiplication of the Trichoderma sp. Sago and dalia proved to be a good substrate for the bioagent under study in comparison to the conventional substrate like talc. Among the amendments added in the growth media 1% chitin may be an effective supplement to the growth media for increasing its survival in storage. From the interaction studied between different substrates and different amendments selected for the shelf life study a combination of sago and 1 % chitin found to be efficient for multiplication of Trichoderma isolate. The rate of decline in population was found low for alginate prills both in bentonite and wheat. Rate of decline was higher in organic substrates such as vermicompost, sago and dalia. Rate of decline was observed lower in 0.5% ammonium sulfate and 1% chitin amendment than the control.

Combined Effect of Meteorological Factors on Leaf blight Progression and their Comparison between Two Growth Models (Logistic and Gompertz) for predicting Disease Severity on Mustard

1 2Sunita Mahapatra and Srikanta Das1AICW&BIP, Uttar Banga Krishi Viswavidyalaya, Pundibari,

2 Coochbehar, West Bengal 736 165. Department of Plant Pathology, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal 741252.

Step down multiple regression analysis were used to identify those meteorological parameters useful in explaining variation in severities of Alternaria leaf blight of mustard (Alternaria brassicae and Alternaria brassicicola). Disease severity estimates (Y), maximum temperature (T ), minimum temperature (T ), max min

maximum relative humidity(RH ), minimum relative humidity( max

RH ), total rainfall (RT), maximum wind velocity (WV ), min max

minimum wind velocity (WV ), maximum vapour pressure (VP min

), minimum vapour pressure (VP ), bright sunshine hour (BSH) max min

were used as variable. Different weather variables were influenced differently on disease severity at five different dates of sowing for the two consecutive years. Gompertz equation was best linearized with the disease progress data followed by logistic and untransformed data sets. The linear prediction equations are (1) Y=

th3.203 – 0.356 ( T )+ 0.015 (RH ) for 20 October sowing; (2) Y min min

th= - 1.929 + 1.634 (WV ) + 0.067 (RT) for 5 November sowing; min

(3) Y = - 121.91+ 1.57(T )+ 1.083(RH ) + 0.29(RH ) - min max min

2.27(VP ) - 0.61(VP ) – 17.17(WV ) + 17.83(WV ) max min max min

th+1.65(BSH) + 0.113(RT) for 20 November sowing; (4) Y = - th5.131 + 0.25 (VP )+ 0.256 (BSH)+ 0.057 (RT) for 5 December max

thsowing; (5) Y = - 3.19 + 0.235(T ) for 20 December sowing.min

Evaluation of Cucumber Germplasm Health against Downy Mildew Disease for their Value Added Utilization

MK Bag*, Pragya, A Roy and KK Gangopadhyay

Germplasm Evaluation Division, National Bureau of Plant Genetic Resources, New Delhi 110012, India. E-mail: manas.bag@gmail.com

Conservation of healthy germplasm is important for successful crop improvement programme. Cucumber (Cucumis sativus L.) is one of the most important indigenous vegetables consumed throughout the world in salad, cooked and pickle form. Cucumber is often regarded as health foodof its low calorie content and presence of vitamins and minerals. Cucumber is highly susceptible to a range of diseases and pests which hinders its commercial production. Cucumber is known to be the most preferred host for almost all types of viruses affecting Cucurbitaceous crops. Despite the presence of vast genetic diversity throughout the country, the Indian cucumber germplasm has not been fully exploited for identification of useful source of resistance to various biotic and abiotic stresses as well as its status regarding resistant against downy mildew disease. Downy mildew, a foliar disease caused by Pseudoperonospora cubensis (Berk. and Curt.) Rostov. is one of the most destructive diseases of cucumber. Moderately resistant cultivars are available, but yield losses are high without the use of fungicides. With the objective to identify resistant source for downy mildew disease, a total of 88 accessions of cucumber collected from different parts of India were screened during Kharif 2012 at NBPGR farm, New Delhi. Percent disease severity was observed 100 in case of 9 accessions. Pusa Uday and Pusa Harit are two varieties taken as check variety has shown 100% disease severity. 40 to 80 percent disease severity was observed in 59 accessions. Out of 88 accessions, 7 accessions were found promising because severity was less than 10%. Promising accessions are IC527394, IC527397, IC527400, IC527404, IC527405, IC527423 and EC738032. These promising germplasm could be utilized for evolving disease resistant varieties with desirable quality traits.

Biochemical Variation of Some Alternaria species Infected on Different Floricultural Plants

1BS Ambesh* and Srikanta Das

Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Krishi, Viswavidyalaya, Pundibari, Cooch Behar 736 165, W.B1Department of Plant Pathology, Faculty of Agriculture, Bidhan Chandra Krishi, Viswavidyalaya, Mohanpur, Nadia-741252, West Bengal, Email: bharatambesh@gmail.com

Alternaria spp. is an economically important pathogen widely distributed throughout the world and cause devastated disease on tuberose, marigold, rose, gladiolus and other floricultural crops. Isozyme analysis revealed considerable diversity among isolates of Alternaria spp. The isozyme tested in native polyacrylamide gel electrophoresis (PAGE), â- esterase produced well resolved electrophoretic phenotypes that could be used as markers for the isolates. Isozyme pattern particularly â- esterase produces different bands with different Rm value. Clustering analysis of these isozyme profiles showed two clusters among the four isolates. In the first cluster, tuberose and rose isolates were grouped together and in second cluster, gladiolus and marigold isolates. Though tuberose, gladiolus, marigold and rose isolates produces different amount of phenol and carbohydrate. So, it can be concluded from this study that Alternaria spp. of four host cultivars exists high isozyme variability among themselves.

Ecofriendly Management of Yellow Mosaic Virus of Mungbean by using Botanical Oils

1Dharnendra Reang* and PS Nath

J Mycol Plant Pathol, Vol. 42, No.4, 2012 547

Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal 736 165.Department of Plant Pathology, Faculty of Agriculture, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia-741252, West Bengal, Email: danenreang@gmail.com

Mungbean or green gram, scientifically known as Vigna radiata L. Wilczek, is one of the important short duration pulse crops of Indian origin. In West Bengal, mungbean is the principle pulse crop and mainly grown in Pre-Kharif and Kharif season. Mungbean is known to be affected by several diseases, incited by viruses, fungi, bacteria and nematodes. Of the various viral diseases Yellow Mosaic is widely distributed and most destructive. Considering the immense economic significance of 'Mungbean Yellow Virus disease' Investigations are being carried out both at the national and international levels of different aspects of this disease particularly on the management by means of, suitable tolerant varieties, control of it insect vector (Bemisia tabaci Genn.) by using botanicals oils. But spraying of chemical insecticides possesses a threat to environment and health hazard. So, considering this fact, experiment was conducted to control the disease by alternative methods like spraying of eco friendly botanical oils and to search tolerant varieties. Among the five plant origin oil products with different doses were tested for spraying, Neem@ 0.2% showed lowest incidence (10.49%) and severity (9.58%) and the percentage of disease control was 77.94 and 77.55 respectively. Significant highest yield (1.78 kg/plots) was also recorded in Neem@ 0.2% sprayed plots. The population of whitefly was low in Neem oil@0.2% treated plots (2.25 per plants). So, Neem oil@ 0.2% is recommended for the control of the disease in the plains of West Bengal.

Refocusing the Plant Disease Pattern under Changing Climate Scenario

1 2 3K Pradhan , Soma Biswas and S Biswas1 Assistant Professor, Department of Agricultural Extension, UBKV,

2.Pundibari, Coochbehar. Subject Matter Specialist (Agricultural 3.Extension), Coochbehar KVK, UBKV, Pundibari, Coochbeha. Subject

Matter Specialist (Soil Science), Coochbehar KVK, UBKV, Pundibari, Coochbehar

Under changed climate scenario, the dynamics of the plant disease pattern is gaining a momentum for huge crop loss vis a vis loss of earning in the rural areas. The disease complex in case of crops cultivated is very much situation specific and demands a special consideration to solve the problem in field situation. The interrelated climate, land, water, vegetation and human activity determine the ever changing environment on the earth. The apparent plasticity of some agricultural systems may help to minimize negative impacts of climate change through the adoption of new adapted cultivars and other practices. However, despite significant improvements in technology, diseases continue to impose significant constraints to production under the current climate. Disease may further restrict the limited range of crops or cultivars that are adapted to a changing climate. The emerging body of knowledge strongly suggests that climate change, especially changes in precipitation, events environment and atmospheric composition will significantly add to the complex interaction between technological and socio-economic changes in influencing plant diseases. In future the potential impacts of climate change would be observed in three areas a) changes in crop loss due to diseases, b) effectiveness of management strategies and

c) geographical distribution of diseases. In such a research climate, a study was conducted with an aim to refocus the existing plant disease pattern in the district of Coochbehar, West Bengal under the changed climate perspective. Three villages at Coochbehar-II block in Coochbehar district were selected purposively. The data were collected with the help of semi structured interview schedule through focus group discussion method. Each focus group contains fifteen respondents. The data were collated and interpreted to find out the existing plant disease pattern in the study area and analyze the socio-economic and socio-personal characters of the respondents related with the study.

Stress Induced Antioxidant Enzyme Activity Contributes to Water Deficit Stress Tolerance in Groundnut (Arachis hypogaea L.)

K Chakraborty*, KA Kalariya, Nisha Goswami and AL Singh

Directorate of Groundnut Research, Ivnagar Road, P.B. No. 5, Junagadh – 362 001, Gujarat

Groundnut is an important oilseed which is mostly grown under rain-fed condition in various parts of India. Because of changing climatic scenario and erratic rainfall pattern it quite often faces severe water-deficit stress during the crop season. Hence, a field experiment was conducted with six Spanish cultivars viz. 'SG 99', 'ICGS 44', 'ICGV 86031', 'TAG 24', 'AK 159' and 'DRG 1' during summer 2011 to study the characters of oxidative stress tolerance and activities of antioxidant enzymes under water-deficit condition. Stress was imposed by withholding irrigation from 31 to 62 DAS and then again from 62 to 87 DAS, during flowering (WS 1) and pod development stages (WS 2) respectively. Although in WS 1 the total chlorophyll content increased in all the cultivars except 'SG 99', but in WS 2 it reduced in all the cultivars ranging from 5.5% ('ICGS 44') to 16.2% ('DRG 1'). Membrane stability index (MSI) decreased under water-deficit stress in both flowering and pod development stage and the reduction was highest in 'DRG 1' (22.1%) in pod development stage compared to that of non-stressed plants. Production of reactive oxygen species in terms of H O and superoxide radical (SOR), and lipid peroxidation was 2 2

more at both flowering and pod development stages with highest SOR content in 'ICGV 86031' and 'DRG 1'. Similarly, H O content 2 2

in 'ICGV 86031' increased in both WS 1 and WS 2. The result showed that 'ICGS 44' and 'TAG 24' had high recovery capacity with least H O production during the stress relief. Activity of the 2 2

antioxidant enzymes viz. superoxide dismutase was high especially during pod development stage in 'ICGS 44' and 'TAG 24'. Similarly, the activities of other enzymes like catalase, peroxidase, glutathione reductase and ascorbate peroxidase showed increase under water-deficit stress. Compared to other cultivars, 'ICGS 44' and 'TAG 24' showed better tolerance capacity by maintaining higher relative water content and antioxidant enzyme activity, and sustaining much less membrane injury due to imposition of water-deficit stress.

Expression Analysis of the Zinc Transporter (Zip) Gene Family and its Application as Marker to Identify the High Kernel Zn Content in Maize (Zea mays)

Tapan Kumar Mondal* and Showkat Ahemd Genei

J Mycol Plant Pathol, Vol. 42, No.4, 2012548

National Research Centre on DNA Fingerprinting, National Bureau of

Plant Genetic Resource, New Delhi- 110012, India E-

mail:mondaltk@yahoo.com

ZRT-IRT-like Protein (ZIP) is an important metal transporter

family in plants which has a characteristic ZIP domain (Pfam:

PF02535). Although several genes belongs to ZIP family have

been discovered, yet genome wide analysis of the paralouges and

their relationship among the other related genera has not been

conducted so far. Thus, a genome-wide analysis was carried out

which identified 12 member in ZIP family gene in maize genome.

Chromosomal location, protein domain and motif organization,

characterization of protein of ZIP genes were analyzed in maize

genome. The phylogenetic relationships, gene duplications and

expression profiles of ZIP genes were also presented in this study.

Twelve ZIP genes were classified into three major classes (class A,

B, and C) according to their structural characteristics and

phylogenetic comparisons. Further, the expression of all 12

member of genes were studied in high and low kernel zinc

containing maize inbred at vegetative and reproductive stage (Flag

leaf, kernel after 10 DAP) by Q-PCR which indicate two members

are highly expressed in high kernel Zn inbred line. SNP markers

based on these two paralogues are found to discriminate among the

different maize inbred lines with contrasting kernel Zn content.

The result demonstrated that ZIP family in maize has differential

expression pattern among the high and low kernel zinc containing

inbred in maize and are potential to use as diagnostic markers.

Cloning, Characterization and Development of

SNP Markers of Calcium Exchanger (CAX) and

Glutamine Synthatase (GS) Genes in Cowpea

[Vigna unguiculata (L.) Walp.]

*Tapan Kumar Mondal , Showkat Ahemed Genei and

Mukesh Kumar Rana National Research Centre on DNA Fingerprinting, National Bureau of

Plant Genetic Resources, IARI Campus, Pusa, New Delhi-110012

Email: mondaltk@yahoo.com

Cowpea (Vigna unguiculata (L.) Walp.) is an important legume

which is used as food and fodder in India. While calcium

exchanger (CAX) gene is responsible for accumulation high

calcium in plant which is important for nutritional point of view,

glutamine synthatase (GS) is a drought stress responsive enzyme.

Therefore, both the genes encoding calcium exchanger and

glutamine synthatase from cowpea (Vigna unguiculata (L.) Walp.)

were isolated and designated as cowpea calcium exchanger:

VuCAX1 and glutamine synthatase: VuGS1. In silico analysis

deduced amino acid sequence, characteristic conserved domain,

secondary structure which showed high degree of homology with

other respective similar genes of angiosperms. Semi-quantitative

RT-PCR detected the expression in different parts of the cowpea

plant. Further while VuCAX1 was induced by zinc deficiency yet

VuGS1 was induced by drought stress. Additionally, in order to

find out the allelic variations of both the genes, the ORF was

cloned from a set of diverse cowpea accessions and some novel

single nucleotide polymorphism were found in the coding region

which could serve as potential molecular markers in cowpea

breeding program.

Biochemical Responses of Different Wheat

(Triticum aestivum L.) Cultivars to Salinity

Stress

B Pradhan and U Chakraborty*

Plant Biochemistry Laboratory, Department of Botany, University of North Bengal, Siliguri, Darjeeling 734013, West Bengal, India, Email: chakrabortyusha@hotmail.com

Salt stress of 50mM, 100mM and 200mM was applied to nine different varieties of wheat (Triticum aestivum L.) - Mohan Wonder (MW), Kedar (KD), Gayetri (GY), Gandhari (GN), Kaweri (KW), PBW 343, UP 2752, Sonalika (SO), Local variety

st rd(LV) and sampling was done on the 1 and 3 day in all cases. Lower decrease in relative water content (RWC), higher values of membrane stability index (MSI) and increased levels of total antioxidant were observed in KD, GN, KW, UP 2752 and PBW 343 with increase in the severity of salinity stress than in MW, GY, SO and LV. Among the antioxidative enzymes, catalase (CAT) and superoxide dismutase (SOD) showed a decrease in MW, GY, LV and SO whereas there was an initial enhancement in case of the other varieties. Peroxidase (POX) and glutathione reductase (GR) activity increased in all the varieties following salt stress; however, a decrease was observed in case of MW, GY, LV and SO during higher concentration of salt. Ascorbate peroxidase (APOX) activity declined during higher concentration of salt with an initial enhancement following salt stress in all the varieties. In case of MW, GY, and LV and SO accumulation of hydrogen peroxide (H O ), lipid peroxidation showed increase following salt stress. A 2 2

concentration dependent increase in H O staining was observed in 2 2

the stressed leaf evident as brown coloured spots due to 3, 3-diaminobenzidine tetra hydrochloride (DAB) polymerization in comparison with the control plants. Stress responsive metabolites such as proline, total carbohydrates and antioxidants like phenol, total antioxidant, ascorbate and carotenoid content showed a significant enhancement with increase in the concentration and duration of salt stress. According to the results of the present study KD, GN, KW KD showed the highest tolerance to salinity stress followed by PBW 343, UP 2752 and MW, GY and SO showed the least tolerance to salinity stress.

Effects of Pruning on Growth of Jatropha curcas L. under Rain-fed Condition

AN Dey* and Bani Sharma

Department of Forestry, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, 736 165, West Bengal E- mail: amarendra_dey@rediffmail.com

Various intensities of pruning or lopping generally effect the growth and biomass of the trees. Jatropha curcas L. is a popular energy crop in tropical and sub-tropical countries which has multiple uses including supply of energy in the raw form or as biodiesel. The objective of the study about the pruning intensities

ndwas to determine the effects of pruning level in 2 year of growth of Jatropha curcas. 25%, 50% and 75% whole plant pruning and 25%, 50% and 75% primary branch and secondary branch pruning were done with a control in the experimental plot of Uttar Banga Krishi Viswavidyalaya; Pundibari, Cooch Behar, West Bengal during the year 2011-12. This experiment was aimed to optimize the pruning level which will enhance the production of more number of branches, healthy inflorescence and encourage the good

J Mycol Plant Pathol, Vol. 42, No.4, 2012 549

fruit set and ultimately the yield. The experiment revealed that pruning of 50 % pruning of primary and secondary branch is ideal to manage.

Management of Abiotic and Biotic Stresses in Plants—Light on some Indigenous Technical Knowledge (ITK)

1* 2PK Pal and Ranjit Chatterjee1Assistant Professor (Sr. Scale), Department of Agricultural Extension,

2Faculty of Agriculture & Assistant Professor (Sr. Scale), Department of Vegetable and Spice Crops, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, P.O.- Pundibari, Cooch Behar. West Bengal, INDIA. PIN-736165. E-mail: pkpalubkv@gmail.com

The technologies that are generated out of farmers own knowledge and experience in dealing with day-to-day problems are called Indigenous Technical Knowledge (ITK). These technologies evolved through trial and error methods over generations and are utilised by the farmers in their production systems. An abiotic stress defined as the negative impact of non-living factors on the living organisms ranges from the stresses generated out of adverse climatic factors to unhealthy soil systems, whereas biotic stress include such living disturbances as diseases harmful insects, or anthropogenic activities harmful to growth and development of the living system under consideration. The farmers over generations gathered a vast pool of indigenous knowledge base to overcome such stresses. Sometimes, they modify the modern recommendations of their production systems too to get rid of such adverse conditions. The present paper highlighted some specific stresses and the ITKs to overcome these stresses. The ITKs are described in respect of the specific abiotic or biotic stresses the farmers faced; on the perspective of the farmers' socio-economic status; or based on the farmers' rationality. The present study also assessed the extent of use of these ITKs in field level in the study areas.

Differential Responses of Six Varieties of Maize (Zea mays L.) to Water Stress and their Antioxidant Defense Systems

R Lama and U Chakraborty*

Plant Biochemistry Laboratory, Department of Botany, University of North Bengal, Siliguri, Darjeeling 734 013, West Bengal, Email: chakrabortyusha@hotmail.com

The variable responses of drought were tested on one month old plants of six varieties of maize – 30V92, KS 244, K 244+, BN101 Swarna and Dhanya by withholding water for 3, 5 and 7 days. Antioxidative enzymes peroxidase (POX), ascorbate peroxidase (APOX), glutathione reducatases (GR) and superoxide dismutase (SOD) showed an increase in activity during initial stages of stress in all tested varieties. In KS 244, KS244+ and BN 101 POX, GR and CAT activity showed a significant increase with prolonged stress. But in other three varieties POX and GR activity decreased

thafter the 5 day of stress; CAT activity showed a different trend in these three varieties where activity declined during the period of stress. APOX and SOD showed similar type of activity in all the six varieties where activity increased during initial stages and

thdecreased after the 5 day of stress. Ascorbate content increased during drought, with maximum in BN 101, KS 244, and K 244+. Proline content was observed to increase following water stress

while chlorophyll content showed a significant decrease in all varieties. Water stress enhanced lipid peroxidation in all varieties, whereas hydrogen peroxide (H O ) accumulation significantly 2 2 ,

increased in Dhanya, Swarna and 30V92 during all periods of stress. Results indicate that while water stress causes oxidative damage the ability to withstand prolonged stress as indicated by antioxidant responses is greater in BN 101, KS 244 and K244+ which can be considered as tolerant.

Antioxidative Responses of Mandarin (Citrus reticulata) to Water Logging

1 1 2Sanjita Allay , BN Chakraborty, Rohini Lama and 2Usha Chakraborty

1 2 Immuno-Phytopathology Laboratory, Plant Biochemistry Laboratory, Department of Botany, University of North Bengal, Siliguri 734 013, West Bengal

Biotic and abiotic stresses in plants are the results of unfavorable environmental conditions plants. Flooding is a stress that crop plants frequently encounter and results in huge economic losses. Mild flooding is experienced by most land plants; as its severity increases, fewer species are able to grow and survive. Citrus reticulata grows in warm climatic conditions. Abiotic and biotic stress condition may results in extensive loss on citrus production. Stresses such as water logging, soil acidity, unbalanced nutrition and pathogenic infestation leads to root injury resulting in citrus tree decline. In order to determine the effect of flooding on mandarin plants four replicates of mandarin plants were left in water logging condition in the field. Biochemical and morphological changes induced by water logging conditions was determined. The plants showed slight wilting and leaf dropping by the third day of flooding stress. Marked changes in antioxidative enzymes like peroxidase, catalase and ascorbate peroxidase was observed during flooding in comparison to the control plant. Antioxidative activity was seen to be more in the leaves than in the roots. Among the antioxidants carotenoid content showed a significant decrease during the stressed period in all the replicates but an increase in ascorbate content was observed during stress in comparison to the control. From this study, we can conclude that water logging stress causes adjustment of antioxidant balance in mandarin plants.

Abiotic Stress on Urban Trees

Sumit Chakravarty* and Gopal Shukla

Department of Forestry, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, Pundibari- 736 165, West Bengal, Email: c_drsumit@yahoo.com

Despite environments which are often unfavorable for plant growth, the human inhabitants of most metropolitan/urban areas are increasingly dependent upon urban trees for the aesthetic and beneficial amenities they expect from nature. Much of the available information on urban trees has been gleaned from studies on forest trees: a situation that is certainly less than satisfactory. In terms of physiological response, the most important aspect of urbanization involves the environmental constraints imposed on landscape trees. These restraints may be categorized as biotic or abiotic. Biotic factors, including insect and disease problems, are frequently important only after city trees have been adversely affected by abiotic factors much as moisture, temperature, light, etc. The paper is a review of some important abiotic stress factors and how they may influence the growth of urban trees.

J Mycol Plant Pathol, Vol. 42, No.4, 2012548

National Research Centre on DNA Fingerprinting, National Bureau of

Plant Genetic Resource, New Delhi- 110012, India E-

mail:mondaltk@yahoo.com

ZRT-IRT-like Protein (ZIP) is an important metal transporter

family in plants which has a characteristic ZIP domain (Pfam:

PF02535). Although several genes belongs to ZIP family have

been discovered, yet genome wide analysis of the paralouges and

their relationship among the other related genera has not been

conducted so far. Thus, a genome-wide analysis was carried out

which identified 12 member in ZIP family gene in maize genome.

Chromosomal location, protein domain and motif organization,

characterization of protein of ZIP genes were analyzed in maize

genome. The phylogenetic relationships, gene duplications and

expression profiles of ZIP genes were also presented in this study.

Twelve ZIP genes were classified into three major classes (class A,

B, and C) according to their structural characteristics and

phylogenetic comparisons. Further, the expression of all 12

member of genes were studied in high and low kernel zinc

containing maize inbred at vegetative and reproductive stage (Flag

leaf, kernel after 10 DAP) by Q-PCR which indicate two members

are highly expressed in high kernel Zn inbred line. SNP markers

based on these two paralogues are found to discriminate among the

different maize inbred lines with contrasting kernel Zn content.

The result demonstrated that ZIP family in maize has differential

expression pattern among the high and low kernel zinc containing

inbred in maize and are potential to use as diagnostic markers.

Cloning, Characterization and Development of

SNP Markers of Calcium Exchanger (CAX) and

Glutamine Synthatase (GS) Genes in Cowpea

[Vigna unguiculata (L.) Walp.]

*Tapan Kumar Mondal , Showkat Ahemed Genei and

Mukesh Kumar Rana National Research Centre on DNA Fingerprinting, National Bureau of

Plant Genetic Resources, IARI Campus, Pusa, New Delhi-110012

Email: mondaltk@yahoo.com

Cowpea (Vigna unguiculata (L.) Walp.) is an important legume

which is used as food and fodder in India. While calcium

exchanger (CAX) gene is responsible for accumulation high

calcium in plant which is important for nutritional point of view,

glutamine synthatase (GS) is a drought stress responsive enzyme.

Therefore, both the genes encoding calcium exchanger and

glutamine synthatase from cowpea (Vigna unguiculata (L.) Walp.)

were isolated and designated as cowpea calcium exchanger:

VuCAX1 and glutamine synthatase: VuGS1. In silico analysis

deduced amino acid sequence, characteristic conserved domain,

secondary structure which showed high degree of homology with

other respective similar genes of angiosperms. Semi-quantitative

RT-PCR detected the expression in different parts of the cowpea

plant. Further while VuCAX1 was induced by zinc deficiency yet

VuGS1 was induced by drought stress. Additionally, in order to

find out the allelic variations of both the genes, the ORF was

cloned from a set of diverse cowpea accessions and some novel

single nucleotide polymorphism were found in the coding region

which could serve as potential molecular markers in cowpea

breeding program.

Biochemical Responses of Different Wheat

(Triticum aestivum L.) Cultivars to Salinity

Stress

B Pradhan and U Chakraborty*

Plant Biochemistry Laboratory, Department of Botany, University of North Bengal, Siliguri, Darjeeling 734013, West Bengal, India, Email: chakrabortyusha@hotmail.com

Salt stress of 50mM, 100mM and 200mM was applied to nine different varieties of wheat (Triticum aestivum L.) - Mohan Wonder (MW), Kedar (KD), Gayetri (GY), Gandhari (GN), Kaweri (KW), PBW 343, UP 2752, Sonalika (SO), Local variety

st rd(LV) and sampling was done on the 1 and 3 day in all cases. Lower decrease in relative water content (RWC), higher values of membrane stability index (MSI) and increased levels of total antioxidant were observed in KD, GN, KW, UP 2752 and PBW 343 with increase in the severity of salinity stress than in MW, GY, SO and LV. Among the antioxidative enzymes, catalase (CAT) and superoxide dismutase (SOD) showed a decrease in MW, GY, LV and SO whereas there was an initial enhancement in case of the other varieties. Peroxidase (POX) and glutathione reductase (GR) activity increased in all the varieties following salt stress; however, a decrease was observed in case of MW, GY, LV and SO during higher concentration of salt. Ascorbate peroxidase (APOX) activity declined during higher concentration of salt with an initial enhancement following salt stress in all the varieties. In case of MW, GY, and LV and SO accumulation of hydrogen peroxide (H O ), lipid peroxidation showed increase following salt stress. A 2 2

concentration dependent increase in H O staining was observed in 2 2

the stressed leaf evident as brown coloured spots due to 3, 3-diaminobenzidine tetra hydrochloride (DAB) polymerization in comparison with the control plants. Stress responsive metabolites such as proline, total carbohydrates and antioxidants like phenol, total antioxidant, ascorbate and carotenoid content showed a significant enhancement with increase in the concentration and duration of salt stress. According to the results of the present study KD, GN, KW KD showed the highest tolerance to salinity stress followed by PBW 343, UP 2752 and MW, GY and SO showed the least tolerance to salinity stress.

Effects of Pruning on Growth of Jatropha curcas L. under Rain-fed Condition

AN Dey* and Bani Sharma

Department of Forestry, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, 736 165, West Bengal E- mail: amarendra_dey@rediffmail.com

Various intensities of pruning or lopping generally effect the growth and biomass of the trees. Jatropha curcas L. is a popular energy crop in tropical and sub-tropical countries which has multiple uses including supply of energy in the raw form or as biodiesel. The objective of the study about the pruning intensities

ndwas to determine the effects of pruning level in 2 year of growth of Jatropha curcas. 25%, 50% and 75% whole plant pruning and 25%, 50% and 75% primary branch and secondary branch pruning were done with a control in the experimental plot of Uttar Banga Krishi Viswavidyalaya; Pundibari, Cooch Behar, West Bengal during the year 2011-12. This experiment was aimed to optimize the pruning level which will enhance the production of more number of branches, healthy inflorescence and encourage the good

J Mycol Plant Pathol, Vol. 42, No.4, 2012 549

fruit set and ultimately the yield. The experiment revealed that pruning of 50 % pruning of primary and secondary branch is ideal to manage.

Management of Abiotic and Biotic Stresses in Plants—Light on some Indigenous Technical Knowledge (ITK)

1* 2PK Pal and Ranjit Chatterjee1Assistant Professor (Sr. Scale), Department of Agricultural Extension,

2Faculty of Agriculture & Assistant Professor (Sr. Scale), Department of Vegetable and Spice Crops, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, P.O.- Pundibari, Cooch Behar. West Bengal, INDIA. PIN-736165. E-mail: pkpalubkv@gmail.com

The technologies that are generated out of farmers own knowledge and experience in dealing with day-to-day problems are called Indigenous Technical Knowledge (ITK). These technologies evolved through trial and error methods over generations and are utilised by the farmers in their production systems. An abiotic stress defined as the negative impact of non-living factors on the living organisms ranges from the stresses generated out of adverse climatic factors to unhealthy soil systems, whereas biotic stress include such living disturbances as diseases harmful insects, or anthropogenic activities harmful to growth and development of the living system under consideration. The farmers over generations gathered a vast pool of indigenous knowledge base to overcome such stresses. Sometimes, they modify the modern recommendations of their production systems too to get rid of such adverse conditions. The present paper highlighted some specific stresses and the ITKs to overcome these stresses. The ITKs are described in respect of the specific abiotic or biotic stresses the farmers faced; on the perspective of the farmers' socio-economic status; or based on the farmers' rationality. The present study also assessed the extent of use of these ITKs in field level in the study areas.

Differential Responses of Six Varieties of Maize (Zea mays L.) to Water Stress and their Antioxidant Defense Systems

R Lama and U Chakraborty*

Plant Biochemistry Laboratory, Department of Botany, University of North Bengal, Siliguri, Darjeeling 734 013, West Bengal, Email: chakrabortyusha@hotmail.com

The variable responses of drought were tested on one month old plants of six varieties of maize – 30V92, KS 244, K 244+, BN101 Swarna and Dhanya by withholding water for 3, 5 and 7 days. Antioxidative enzymes peroxidase (POX), ascorbate peroxidase (APOX), glutathione reducatases (GR) and superoxide dismutase (SOD) showed an increase in activity during initial stages of stress in all tested varieties. In KS 244, KS244+ and BN 101 POX, GR and CAT activity showed a significant increase with prolonged stress. But in other three varieties POX and GR activity decreased

thafter the 5 day of stress; CAT activity showed a different trend in these three varieties where activity declined during the period of stress. APOX and SOD showed similar type of activity in all the six varieties where activity increased during initial stages and

thdecreased after the 5 day of stress. Ascorbate content increased during drought, with maximum in BN 101, KS 244, and K 244+. Proline content was observed to increase following water stress

while chlorophyll content showed a significant decrease in all varieties. Water stress enhanced lipid peroxidation in all varieties, whereas hydrogen peroxide (H O ) accumulation significantly 2 2 ,

increased in Dhanya, Swarna and 30V92 during all periods of stress. Results indicate that while water stress causes oxidative damage the ability to withstand prolonged stress as indicated by antioxidant responses is greater in BN 101, KS 244 and K244+ which can be considered as tolerant.

Antioxidative Responses of Mandarin (Citrus reticulata) to Water Logging

1 1 2Sanjita Allay , BN Chakraborty, Rohini Lama and 2Usha Chakraborty

1 2 Immuno-Phytopathology Laboratory, Plant Biochemistry Laboratory, Department of Botany, University of North Bengal, Siliguri 734 013, West Bengal

Biotic and abiotic stresses in plants are the results of unfavorable environmental conditions plants. Flooding is a stress that crop plants frequently encounter and results in huge economic losses. Mild flooding is experienced by most land plants; as its severity increases, fewer species are able to grow and survive. Citrus reticulata grows in warm climatic conditions. Abiotic and biotic stress condition may results in extensive loss on citrus production. Stresses such as water logging, soil acidity, unbalanced nutrition and pathogenic infestation leads to root injury resulting in citrus tree decline. In order to determine the effect of flooding on mandarin plants four replicates of mandarin plants were left in water logging condition in the field. Biochemical and morphological changes induced by water logging conditions was determined. The plants showed slight wilting and leaf dropping by the third day of flooding stress. Marked changes in antioxidative enzymes like peroxidase, catalase and ascorbate peroxidase was observed during flooding in comparison to the control plant. Antioxidative activity was seen to be more in the leaves than in the roots. Among the antioxidants carotenoid content showed a significant decrease during the stressed period in all the replicates but an increase in ascorbate content was observed during stress in comparison to the control. From this study, we can conclude that water logging stress causes adjustment of antioxidant balance in mandarin plants.

Abiotic Stress on Urban Trees

Sumit Chakravarty* and Gopal Shukla

Department of Forestry, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, Pundibari- 736 165, West Bengal, Email: c_drsumit@yahoo.com

Despite environments which are often unfavorable for plant growth, the human inhabitants of most metropolitan/urban areas are increasingly dependent upon urban trees for the aesthetic and beneficial amenities they expect from nature. Much of the available information on urban trees has been gleaned from studies on forest trees: a situation that is certainly less than satisfactory. In terms of physiological response, the most important aspect of urbanization involves the environmental constraints imposed on landscape trees. These restraints may be categorized as biotic or abiotic. Biotic factors, including insect and disease problems, are frequently important only after city trees have been adversely affected by abiotic factors much as moisture, temperature, light, etc. The paper is a review of some important abiotic stress factors and how they may influence the growth of urban trees.

J Mycol Plant Pathol, Vol. 42, No.4, 2012550

Some Weather Parameters and Fruit Drop of Mango: A Correlation Study

1 2Nilesh Bhowmick , NM Alam1 Lecturer, Dept. of Pomology and Post Harvest Technology, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, PO- Pundibari,

2Dist- Cooch Behar, West Bengal, India, Pin 736165. Scientist, CSWCTI, Dehradun, ICAR

Fruit drop of mango is one of the major constraints for its successful cultivation. Several factors, i.e, hormonal imbalance, pollination factors, climatologically factors are reported for responsible of fruit drop at different stages of fruit growth and development. In this present preliminary investigation, attempt was made to correlate the effect of different weather factors with the fruit drop rate of nine mango varieties grown under the new alluvial zone of West Bengal. The weekly fruit drop rate was evaluated with weather parameters like, average temperature, rainfall, humidity, evapotranspiration, vapour pressure deficit and soil temperature. For most of the cases, fruit drop rate showed negative correlations with the weather parameters.

Effect of Cultivars and Biofertilizer to Mitigate the Thermo Stress in Cauliflower

1 2Ranjit Chatterjee* , PM Bhattacharya and P 3Mukhopadhyay

1 2Department of Vegetable and Spice Crops, Department of Plant 3Pathology, Director of Extension Education, Uttar Banga Krishi

Viswavidyalaya, Pundibari, Cooch Behar, 736 165, West Bengal. Email: ranchat22@rediffmail.com

Cauliflower is an important member of cole group of vegetable and possess considerable amount of protein, minerals and vitamins along with anti cancerous substances. Temperature plays important role on crop growth, curd initiation-development and maturity. Again initiations of flower stalk and boron sensitivity were aggravated with temperature variation. Keeping the fact in mind an experiment was conducted to find out the effect of temperature on crop growth and to identify suitable cultivar(s) that can produced economic yield under different temperature regime. In addition to that whether biofertilizer intervention can minimize the thermo stress for marketable curd was also studied. Seven popular cauliflower hybrids were planted in three different planting dates in presence of Azotobacter and PSB containing biofertilizer (Azophos).Thus 42 treatment combinations were laid out in split split plot design with three replications. The experiment was conducted during the years 2010-11 and 2011-12 at UBKV, Pundibari, Coochbehar. The pooled result revealed that among the different cultivars Mikado-3 performed consistently for all three planting dates. Again use of biofertilizer inoculation has reduced the thermo stress and increased curd yield over the uninoculated plants.

Environmental Stress and its Management in Spice Crops

Partha Choudhuri* and Ranjit Chatterjee

Department of vegetable and Spice Crops, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch behar, 736 165, West Bengal. Email:partha2909@rediffmail.com

India is called “Land of Spices”.Out of sixty three spices; fifteen numbers of spices are grown commercially in our country. Indian spice is famous in the world export basket for its characteristic flavor and aroma. India is the largest producer, consumer and exporter of spices in the world. Different abiotic factors, specially environmental parameters namely temperature, rainfall, photoperiod, wind, etc. directly or indirectly influence different physiological growth stages like flowering, fruit setting and development, seed setting and finally yield of spice crops of spice crops .high temperature causes spike shedding in black pepper, arid conditions and violent wind are detrimental to plant growth of vanilla. Sudden fall in temperature during early vegetative stage resulted bolting in onion. High humidity and rainfall invite pest like aphid and powdery mildew disease in most of the seed spices like coriander, fenugreek, cumin, etc. The stress effect of environment also influences the seed production and storage life of the spice crops. Apart from different growth and yield attributing inputs extremes of environment also ultimately reduces the yield and quality of the spice crops. By adopting different cultural practices, different threats of environment can be managed economic return from spice crop cultivation may be increased manifold. The full review paper discussed different aspects of environmental stress on spice production and their management for better return.

Use of Protected Structures to Overcome Climatological Stress in Vegetable Production – a Case Study in Coochbehar District of West Bengal.

1Ranjit Chatterjee, Sandip Mahanto* and PK Pal1Department of Vegetable and Spice Crops, Department of Agricultural

Extension, Uttar Banga Krishi Viswavidyalaya, Pundibari, CoochBehar-736165(W.B), India. Email: sandipmahanta.2009@rediffmail.com

Vegetable cultivation is the primary occupation for a large section of farmers in the district of Coochbehar that contributes a reasonable share in the state vegetable production. The effect of global climate change is also influencing the vegetable production system in the locality. Sudden rises in temperatures as well as irregular precipitation influencing the crop growth, flowering and ultimately cause economic yield loss. Protected structures can play important role to minimize the impact of temperature fluctuation, over/under precipitation, fluctuating sun shine hour and infestation of disease and pest. Farmers are gradually adopting different protected structures to combat the climate vagaries. To understand adoption trend of protected structures, an investigation was carried out during 2011-2012 through questionnaire survey in different vegetable belt of the district. The study revealed that habit of adoption of protected structures namely agro shade net house, poly tunnel, low cost poly house and plastic mulching have increased during last 5 years. As per opinion of the farmers majority of the growers are utilizing sudden temperature rise in winter by growing summer season vegetables preferably okra, cucumber, bitter gourd and bottle gourd during winter months by utilizing different protected structures to fetch early market and higher remuneration. The result also indicate that conventional summer growing vegetables is gradually replaced /occupied by heat tolerant varieties of cool season vegetables like cauliflower, cabbage, radish, palak etc. grown under poly tunnels or shade nets. To minimize the effect of direct hail storm on vegetable nursery as

J Mycol Plant Pathol, Vol. 42, No.4, 2012 551

well as standing vegetable crop, farmers are gradually adopting agro shade net again to manage disease and pest farmers are relying on mosquito net, agro shade net and coloured polythene sheets.

Variation in Production of Volatile Antibiotic by Trichoderma sp. Under Heavy Metal Stressed Condition

Nabakishore Nongmaithem, A Roy and PM Bhattacharya

Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, 736 165, West Bengal.

Metal containing pollutants such as lead, chromium, mercury, uranium, selenium, zinc, arsenic, cadmium, silver, gold, and nickel are increasingly being released into the soil from industrial waste water as well as through chemical fertilizers and pesticides as agriculture applications. Heavy metal pollution in soil and aquatic system has become great environmental concern as they are non-biodegradable and thus persistent in the food chain resulting into a serious threat to human health. Conventional methods for heavy metal reclamation like chemical precipitation, adsorption on activated carbon, electro deposition, reverse osmosis; Phyto-remediation, ultra filtration, ion exchange etc are not often economically feasible. New technologies are required that can reduce heavy metal concentration to environmentally acceptable level at affordable costs. Therefore much attention has been given to the removal of metal ions by microorganisms due to its applications in environmental protection and recovery of toxic or strategic heavy metal. Beside broad spectrum biocontrol activity against wide range of soil borne plant pathogens, plant growth promoting ability and induction of resistance in crop plants by Trichoderma spp., another possible role of these microbes in soil bioremediation is relatively unexplored. However, the response of Trichoderma spp. may undoubtedly vary under metal stress situation. The mechanisms behind their biocontrol potential like competition, lytic enzyme production, hyper-parasitism; antibiosis is significantly affected by the metal stressed micro-habitat condition. In the present investigation, selected Trichoderma isolates were tested in vitro against Rhizoctonia solani for their potential to produce volatile antibiotic under circumstances of nickel and cadmium contaminations. Although the growth of R. solani was significantly affected by the increasing concentration of nickel and cadmium, Trichoderma isolates further added considerable reduction in linear growth of the pathogen due to production of volatile antibiotics. Among the isolates UBMT 4 was found to cause maximum inhibition of linear extension of R. solani (40.78%) and it significantly differed from Tri 18 and UBIB I, which are statistically at par when both the biocontrol agent and pathogen were exposed to different concentrations nickel. Whereas, in case of cadmium, Tri 18 was found to have maximum volatile antibiotic production ability as evidenced through maximum (65.77%) reduction in linear growth of R. solani at 3ppm metal stressed situation. From the study it can be revealed that Instead of reduction in growth of both R. solani and Trichoderma under metal stress, Trichoderma was comparatively more tolerant to high doses of heavy metal and consequently the volatile antibiotics produced by the biocontrol agent provides added effect on mycelial growth inhibition of R. solani under metal stressed situation.

Phenotypic Variation under Salinity Stress and Allelic Diversity in the Saltol QTL Region among Rice Germplasm from Coastal Saline Areas

Krishnendu Chattopadhyay*, Disaree Nath, Rajib Mohanty, DP Singh, RK Sarkar and ON Singh

Central Rice Research Institute, Cuttack, Odisha, India- 753006, E-mail: krishnendu_c@sify.com

After the 'super cyclone' in coastal Odisha and the cyclone 'Aila' in the 'Sundarbans' region of West Bengal, high-yielding rice varieties sensitive to salt stress have often failed there resulting in increment of uncultivated land. As rice is sensitive to salt stress at seedling stage, even low levels of soil salinity with electrical conductivity

-1(ECe) of 5–6 dSm can cause significant reduction in seedling growth and biomass in susceptible varieties. In recent past the Saltol derived from a rice cultivar, 'Pokkali' has been identified as a major QTL for salt tolerance at the seedling stage. Unlike 'Pokkali' many rice genotypes from coastal saline areas in India are yet to be characterized for the Saltol QTL. Under present study we assessed the phenotypic and genotypic diversity in 30 rice germplasm collected from the 'Sundarban' region of West Bengal and Odisha along with 'Pokkali' and a few other indigenous or exotic lines. Allelic dissimilarities in the Saltol region were observed even within the salt-tolerant accessions of 'Pokkali' and 'Chettivirippu'. Unlike UPGMA clustering and 3-D plot derived from principal component analysis based on phenotypes, clusters in UPGMA dendrogram and 3-D arrangements based on polymorphism of microsatellite markers in the Saltol QTL region could not differentiate genotypes according to their tolerance reaction, further depicting the presence of additional QTLs for salt tolerance. In contrary, the UPGMA dendrogram and 3-D plot based on the PCA depicted that all the moderately tolerant genotypes such as 'Patnai', 'Rupshal', 'Matla', 'Talmugur' and 'Kamini' from this area were genetically closer to each other, based on polymorphism of SSR markers present in the Saltol QTL region. But they were found distantly located from 'FL478' as well as 'Pokkali' in the 3-D plot based on microsatellite polymorphism indicating the scope of utilization of these tolerant lines for identification of new physiological mechanism and deployment in breeding for broadening the genetic base for salt tolerance in rice.

Evaluation for Vegetative Stage Drought Tolerance in Rice

SK Dash*, P Swain, SK Pradhan, L Behera, L Bose and ON Singh

Central Rice Research Institute, Cuttack, Odisha-753006, E-mail: skdash139@gmail.com

One month old seedlings of 525 germplasm accessions of early to medium duration maturity were exposed to vegetative stage moisture stress under field condition following an augmented design. The entries were randomized in 4 blocks with five checks (tolerant and susceptible) randomized in every 22 entries. During the stress period, soil moisture content was recorded periodically and was 2.6 to 9.7% under 30 cm soil depths with soil moisture tension of more than 60 kPa. Leaf death score was recorded when most of the entries showed leaf rolling symptom and the score was taken following IRRI SES '0' to '9'scale. Out of 525 entries, 75 entries were observed to be highly tolerant with drought and recovery score SES '1' followed by 188 as moderately tolerant with

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Some Weather Parameters and Fruit Drop of Mango: A Correlation Study

1 2Nilesh Bhowmick , NM Alam1 Lecturer, Dept. of Pomology and Post Harvest Technology, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, PO- Pundibari,

2Dist- Cooch Behar, West Bengal, India, Pin 736165. Scientist, CSWCTI, Dehradun, ICAR

Fruit drop of mango is one of the major constraints for its successful cultivation. Several factors, i.e, hormonal imbalance, pollination factors, climatologically factors are reported for responsible of fruit drop at different stages of fruit growth and development. In this present preliminary investigation, attempt was made to correlate the effect of different weather factors with the fruit drop rate of nine mango varieties grown under the new alluvial zone of West Bengal. The weekly fruit drop rate was evaluated with weather parameters like, average temperature, rainfall, humidity, evapotranspiration, vapour pressure deficit and soil temperature. For most of the cases, fruit drop rate showed negative correlations with the weather parameters.

Effect of Cultivars and Biofertilizer to Mitigate the Thermo Stress in Cauliflower

1 2Ranjit Chatterjee* , PM Bhattacharya and P 3Mukhopadhyay

1 2Department of Vegetable and Spice Crops, Department of Plant 3Pathology, Director of Extension Education, Uttar Banga Krishi

Viswavidyalaya, Pundibari, Cooch Behar, 736 165, West Bengal. Email: ranchat22@rediffmail.com

Cauliflower is an important member of cole group of vegetable and possess considerable amount of protein, minerals and vitamins along with anti cancerous substances. Temperature plays important role on crop growth, curd initiation-development and maturity. Again initiations of flower stalk and boron sensitivity were aggravated with temperature variation. Keeping the fact in mind an experiment was conducted to find out the effect of temperature on crop growth and to identify suitable cultivar(s) that can produced economic yield under different temperature regime. In addition to that whether biofertilizer intervention can minimize the thermo stress for marketable curd was also studied. Seven popular cauliflower hybrids were planted in three different planting dates in presence of Azotobacter and PSB containing biofertilizer (Azophos).Thus 42 treatment combinations were laid out in split split plot design with three replications. The experiment was conducted during the years 2010-11 and 2011-12 at UBKV, Pundibari, Coochbehar. The pooled result revealed that among the different cultivars Mikado-3 performed consistently for all three planting dates. Again use of biofertilizer inoculation has reduced the thermo stress and increased curd yield over the uninoculated plants.

Environmental Stress and its Management in Spice Crops

Partha Choudhuri* and Ranjit Chatterjee

Department of vegetable and Spice Crops, Faculty of Horticulture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch behar, 736 165, West Bengal. Email:partha2909@rediffmail.com

India is called “Land of Spices”.Out of sixty three spices; fifteen numbers of spices are grown commercially in our country. Indian spice is famous in the world export basket for its characteristic flavor and aroma. India is the largest producer, consumer and exporter of spices in the world. Different abiotic factors, specially environmental parameters namely temperature, rainfall, photoperiod, wind, etc. directly or indirectly influence different physiological growth stages like flowering, fruit setting and development, seed setting and finally yield of spice crops of spice crops .high temperature causes spike shedding in black pepper, arid conditions and violent wind are detrimental to plant growth of vanilla. Sudden fall in temperature during early vegetative stage resulted bolting in onion. High humidity and rainfall invite pest like aphid and powdery mildew disease in most of the seed spices like coriander, fenugreek, cumin, etc. The stress effect of environment also influences the seed production and storage life of the spice crops. Apart from different growth and yield attributing inputs extremes of environment also ultimately reduces the yield and quality of the spice crops. By adopting different cultural practices, different threats of environment can be managed economic return from spice crop cultivation may be increased manifold. The full review paper discussed different aspects of environmental stress on spice production and their management for better return.

Use of Protected Structures to Overcome Climatological Stress in Vegetable Production – a Case Study in Coochbehar District of West Bengal.

1Ranjit Chatterjee, Sandip Mahanto* and PK Pal1Department of Vegetable and Spice Crops, Department of Agricultural

Extension, Uttar Banga Krishi Viswavidyalaya, Pundibari, CoochBehar-736165(W.B), India. Email: sandipmahanta.2009@rediffmail.com

Vegetable cultivation is the primary occupation for a large section of farmers in the district of Coochbehar that contributes a reasonable share in the state vegetable production. The effect of global climate change is also influencing the vegetable production system in the locality. Sudden rises in temperatures as well as irregular precipitation influencing the crop growth, flowering and ultimately cause economic yield loss. Protected structures can play important role to minimize the impact of temperature fluctuation, over/under precipitation, fluctuating sun shine hour and infestation of disease and pest. Farmers are gradually adopting different protected structures to combat the climate vagaries. To understand adoption trend of protected structures, an investigation was carried out during 2011-2012 through questionnaire survey in different vegetable belt of the district. The study revealed that habit of adoption of protected structures namely agro shade net house, poly tunnel, low cost poly house and plastic mulching have increased during last 5 years. As per opinion of the farmers majority of the growers are utilizing sudden temperature rise in winter by growing summer season vegetables preferably okra, cucumber, bitter gourd and bottle gourd during winter months by utilizing different protected structures to fetch early market and higher remuneration. The result also indicate that conventional summer growing vegetables is gradually replaced /occupied by heat tolerant varieties of cool season vegetables like cauliflower, cabbage, radish, palak etc. grown under poly tunnels or shade nets. To minimize the effect of direct hail storm on vegetable nursery as

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well as standing vegetable crop, farmers are gradually adopting agro shade net again to manage disease and pest farmers are relying on mosquito net, agro shade net and coloured polythene sheets.

Variation in Production of Volatile Antibiotic by Trichoderma sp. Under Heavy Metal Stressed Condition

Nabakishore Nongmaithem, A Roy and PM Bhattacharya

Department of Plant Pathology, Faculty of Agriculture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, 736 165, West Bengal.

Metal containing pollutants such as lead, chromium, mercury, uranium, selenium, zinc, arsenic, cadmium, silver, gold, and nickel are increasingly being released into the soil from industrial waste water as well as through chemical fertilizers and pesticides as agriculture applications. Heavy metal pollution in soil and aquatic system has become great environmental concern as they are non-biodegradable and thus persistent in the food chain resulting into a serious threat to human health. Conventional methods for heavy metal reclamation like chemical precipitation, adsorption on activated carbon, electro deposition, reverse osmosis; Phyto-remediation, ultra filtration, ion exchange etc are not often economically feasible. New technologies are required that can reduce heavy metal concentration to environmentally acceptable level at affordable costs. Therefore much attention has been given to the removal of metal ions by microorganisms due to its applications in environmental protection and recovery of toxic or strategic heavy metal. Beside broad spectrum biocontrol activity against wide range of soil borne plant pathogens, plant growth promoting ability and induction of resistance in crop plants by Trichoderma spp., another possible role of these microbes in soil bioremediation is relatively unexplored. However, the response of Trichoderma spp. may undoubtedly vary under metal stress situation. The mechanisms behind their biocontrol potential like competition, lytic enzyme production, hyper-parasitism; antibiosis is significantly affected by the metal stressed micro-habitat condition. In the present investigation, selected Trichoderma isolates were tested in vitro against Rhizoctonia solani for their potential to produce volatile antibiotic under circumstances of nickel and cadmium contaminations. Although the growth of R. solani was significantly affected by the increasing concentration of nickel and cadmium, Trichoderma isolates further added considerable reduction in linear growth of the pathogen due to production of volatile antibiotics. Among the isolates UBMT 4 was found to cause maximum inhibition of linear extension of R. solani (40.78%) and it significantly differed from Tri 18 and UBIB I, which are statistically at par when both the biocontrol agent and pathogen were exposed to different concentrations nickel. Whereas, in case of cadmium, Tri 18 was found to have maximum volatile antibiotic production ability as evidenced through maximum (65.77%) reduction in linear growth of R. solani at 3ppm metal stressed situation. From the study it can be revealed that Instead of reduction in growth of both R. solani and Trichoderma under metal stress, Trichoderma was comparatively more tolerant to high doses of heavy metal and consequently the volatile antibiotics produced by the biocontrol agent provides added effect on mycelial growth inhibition of R. solani under metal stressed situation.

Phenotypic Variation under Salinity Stress and Allelic Diversity in the Saltol QTL Region among Rice Germplasm from Coastal Saline Areas

Krishnendu Chattopadhyay*, Disaree Nath, Rajib Mohanty, DP Singh, RK Sarkar and ON Singh

Central Rice Research Institute, Cuttack, Odisha, India- 753006, E-mail: krishnendu_c@sify.com

After the 'super cyclone' in coastal Odisha and the cyclone 'Aila' in the 'Sundarbans' region of West Bengal, high-yielding rice varieties sensitive to salt stress have often failed there resulting in increment of uncultivated land. As rice is sensitive to salt stress at seedling stage, even low levels of soil salinity with electrical conductivity

-1(ECe) of 5–6 dSm can cause significant reduction in seedling growth and biomass in susceptible varieties. In recent past the Saltol derived from a rice cultivar, 'Pokkali' has been identified as a major QTL for salt tolerance at the seedling stage. Unlike 'Pokkali' many rice genotypes from coastal saline areas in India are yet to be characterized for the Saltol QTL. Under present study we assessed the phenotypic and genotypic diversity in 30 rice germplasm collected from the 'Sundarban' region of West Bengal and Odisha along with 'Pokkali' and a few other indigenous or exotic lines. Allelic dissimilarities in the Saltol region were observed even within the salt-tolerant accessions of 'Pokkali' and 'Chettivirippu'. Unlike UPGMA clustering and 3-D plot derived from principal component analysis based on phenotypes, clusters in UPGMA dendrogram and 3-D arrangements based on polymorphism of microsatellite markers in the Saltol QTL region could not differentiate genotypes according to their tolerance reaction, further depicting the presence of additional QTLs for salt tolerance. In contrary, the UPGMA dendrogram and 3-D plot based on the PCA depicted that all the moderately tolerant genotypes such as 'Patnai', 'Rupshal', 'Matla', 'Talmugur' and 'Kamini' from this area were genetically closer to each other, based on polymorphism of SSR markers present in the Saltol QTL region. But they were found distantly located from 'FL478' as well as 'Pokkali' in the 3-D plot based on microsatellite polymorphism indicating the scope of utilization of these tolerant lines for identification of new physiological mechanism and deployment in breeding for broadening the genetic base for salt tolerance in rice.

Evaluation for Vegetative Stage Drought Tolerance in Rice

SK Dash*, P Swain, SK Pradhan, L Behera, L Bose and ON Singh

Central Rice Research Institute, Cuttack, Odisha-753006, E-mail: skdash139@gmail.com

One month old seedlings of 525 germplasm accessions of early to medium duration maturity were exposed to vegetative stage moisture stress under field condition following an augmented design. The entries were randomized in 4 blocks with five checks (tolerant and susceptible) randomized in every 22 entries. During the stress period, soil moisture content was recorded periodically and was 2.6 to 9.7% under 30 cm soil depths with soil moisture tension of more than 60 kPa. Leaf death score was recorded when most of the entries showed leaf rolling symptom and the score was taken following IRRI SES '0' to '9'scale. Out of 525 entries, 75 entries were observed to be highly tolerant with drought and recovery score SES '1' followed by 188 as moderately tolerant with

J Mycol Plant Pathol, Vol. 42, No.4, 2012552

SES score '3', 92 relatively less tolerant with SES score '5', 134 with SES score '7' and 36 as susceptible with SES score '9'. The tolerant checks (Vandana, Vanaprabha, Salumpikit, CR-143-2-2) performed better with SES score ranging between '1-5' where as susceptible check (IR-20) was observed with SES score in the range of '7-9'. All the genotypes were simultaneously grown in a non-tress environment with normal irrigation. Among the genotypes showing moderate stress tolerance having SES score of 3, two genotypes IR74392-135-07 and IR-83928-B-B-56-1

-1 -1recorded better grain yield of 2.90 t ha and 4.2 t h ha respectively under non stress situation.

Productivity of Direct Seeded Rain fed Rice under Moisture Stress Condition – an Experience with Different Methods of Sowing and Seed Priming

Tanmay Patra and Swapan Kumar Maity

Palli Siksha Bhavana (Institute of Agriculture), Visva-Bharati University, Sriniketan, Birbhum, – 731 236 West Bengal, India, E-mail: swapankumar.maity@visva-bharati.ac.in

An experiment on direct seeded rice was conducted at Agriculture Farm of Institute of Agriculture, Visva-Bharati University, Birbhum district, West Bengal during Kharif season (June -

November) of 2011 under upland situation with sandy loam textured soil having soil fertility status low in available N and P and medium in available K and acidic soil reaction (5.57) to assess performance of two rice genotypes under different methods of sowing and effectiveness of seed priming. The treatments were two rice genotypes (Gothra Bidhan 1, GB 1 and IR 36); two methods of sowing (line sowing and dibbling) and seed priming treatment (no priming and hydro-priming) laid out in a completely randomized block design with three replications. The crop was taken under fully rain fed condition without any supplemental irrigation. The total rainfall received during the crop season (July to November) was 840 mm. The crop was spread with 1% KCl solution twice to overcome the moisture stress during rainless period.

It was observed that there were significant differences in the effects of rice genotypes and methods of sowing on the yields of rice and on economic parameters. But the effect of seed priming remained insignificant. The rice genotype GB 1 recorded 36.8% higher grain yield and 51.6% higher net profit over the genotype IR 36. Grain yield and net return recorded under dibbling method of sowing were 19.6% and 46.5% higher respectively over line sowing. From the above findings it can be concluded that the genotype GB 1 and dibbling method of sowing were proved to be superior to genotype IR 36 and line sowing respectively in case of direct seeded rice under rain fed condition.

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