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2. REVIEW OF LITERATURE

Tomato is affected by a number of fungal, bacterial and viral diseases like

damping-off (Pythium aphanidermatum), early blight (Alternaria solani), late blight

(Phytophthora infestans), buckeye rot (Phytophthora nicotianae var parasitica), fusarium

wilt (Fusarium oxysporum f.sp. lycopersici), septoria leaf spot (Septoria lycopersici),

powdery mildew (Leveillula taurica), anthracnose (Colletotrichum phomoides), bacterial

wilt (Ralstonia solanacearum), bacterial leaf spot (Xanthomonas campestris pv.

vesicatoria), bacterial canker (Clavibacter michiganensis pv. michiganensis), tomato

mosaic virus (ToMV), tomato leaf curl virus (TLCV), tomato spotted wilt virus (TSWV),

tomato bunch top virus (TBTV), tomato big bud (TBB) etc. Buckeye fruit rot of unripe

tomato is of serious concern to the farmers around the globe and especially to the small

and marginal hill farmers of Himachal Pradesh. The relevant literature pertaining to

different aspects of present study has briefly been reviewed for guidance and planning of

investigations under the following headings:-

2.1 Occurrence and distribution

2.1.1 Present status

2.1.2 Identification

2.1.3 Effect of media

2.2 Isolation of antagonists and their potential

2.3 Use of ITK based and other organic inputs both in vitro and in vivo

2.3.1 Himsol, matkakhad, panchgavya, vermiwash, biospray

2.3.2 Fresh and fermented cow products

2.3.3 Urine from different cattle

2.4 Use of bioagents

2.5 Use of botanicals and crude extract

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2.6 Use of oils and modified panchgavyas

2.7 Use of commercial products

2.7.1 Use of resistance enhancer

2.8 Screening of germplasm/ cultivars and susceptibility of tomato against the disease

2.9 Integrated management of disease

2.1 Occurrence and Distribution

2.1.1 Present status

This disease (buckeye rot of tomato) has been reported by several workers from

different parts of the world. Sherbakoff (1917) was the first to report it from Florida and

described the causal organism as Phytophthora terrestria. Later, Tucker (1931) reported

P. terrestria as synonym of P. parasitica Dastur. Bewley (1922) reported the disease

from England with some other diseases and mentioned this disease as one of the major

diseases of tomato. Weber (1922) stated buckeye rot of tomato to be of economic

importance and Kendrick (1923) while working on diseases of tomato, eggplant and bell

pepper reported Phytophthora rot identical with the buckeye rot in epidemic form with 40

per cent damage to tomato fruits in Indiana. Heavy losses due to buckeye rot were

reported by Gram et al. (1927) in Denmark. Wager (1935) reported this disease from

Eastern Transvaal, where it was locally known as brown rot (P. parasitica) caused heavy

losses to the green fruits.

The buckeye rot pathogen has been reported to cause damage to different parts of

the tomato plants including fruits. This pathogen has been observed to cause stem and

fruit rots (Richardson 1941; Raicu and Stan; 1973 ; Sharma 1971). Damping-off of

tomato due to P. nicotianae var parasitica has also been reported by Bewley (1922);

Taylor (1924); Samuel (1930); Goidanich (1936); Conners (1937) and Singh and

Srivastava (1953). McIntosh (1951) also reported that unripe fruits were attacked by P.

parasitica. Obrero and Aragaki (1965) reported that green, mature and fully red fruits

were readily rotted and those turning pink at the time of inoculation were resistant to P.

nicotianae var parasitica. Jones and McCarter (1974) reported P. parasitica on tomato

fruits from Georgia.

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In India, buckeye rot of tomato caused by P. nicotianae var parasitica was

reported for the first time from Solan (Himachal Pradesh) by Jain et al. (1961) and

subsequently from Karnataka, Punjab and Haryana, by various workers.

Several species of Phytophthora have been reported in literature to cause fruit rot

of tomato. P. infestans (Mont.) de Bary causing late blight of potato produced similar

symptoms in tomato (Reed 1911). Rotting of tomato fruits have also been reported to be

caused by P. maxicana (Hotson and Hortge 1923), P. drechsleri (Tompkin and Tucker

1941), P.capsici (Simond and Kreutzer 1944), P. palmivora (Thomas et al. 1947) and P.

cryptogea (Williams et al.1943). Richardson (1941) studied the disease in detail and

reported Phytophthora parasitica to be the causal agent.

2.1.2 Identification

The occurrence of Phytophthora parasitica was reported for the first time by

Dastur (1913) on castor (Ricinus communis). Since then the fungus has been studied by a

number of workers. In his classical work, Dastur gave the morphological characters of

the fungus as well as suitability of the different media for its growth and reproduction.

Tucker (1931) while working on the taxonomy of the genus Phytophthora has shown that

morphological characters i.e. the size of reproductive organs are of limited value in the

identification of the species.

Use of PCR-based molecular markers provides an efficient reproducible and

reliable approach to characterize plant pathogen population particularly for the

assessment of genetic diversity and phylogenetic relationships. Internal Transcribed

Spacer (ITS) sequence data have been used to study the phylogenetic relationships of

many Phytophthora spp. (Lee and Taylor 1992). Molecular tools used in phylogenetic

studies of Oomycetes (Forster et al. 1990) have included large and small subunits of

ribosomal RNA genes and sequence analysis of the Internal Transcribed Spacer (ITS)

regions of the rRNA genes (Crawford et al. 1996).

2.1.3 Effect of media

Several culture medium have been developed to determine the growth

characteristics of this pathogen. Richardson (1941); Fulton and Fulton (1951) reported

oat meal agar medium as luxuriant for the growth of the fungus. Dodan (1991) recorded

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maximum growth of different isolates of Phytophthora nicotianae var nicotianae on

OMA (oat meal agar) followed by CMA (corn meal agar), BPA (bean pod agar), PDA

(potato dextrose agar) and others. Hossain and Banik (1999) evaluated six agar media for

vegetative growth and sporulation of P. nicotianae var nicotianae isolated from infected

brinjal and observed that corn meal agar and oatmeal agar media produced maximum

vegetative growth and V8 juice agar medium was the best for sporulation. Mishra et al.

(2010) recorded maximum vegetative growth of P. drechsleri f. sp. cajani on oat meal

agar medium. Higher mycelial growth of P. infestans in rye B medium and higher

sporangial production on V8 and PDA medium was observed by Costa et al (2011).

Tsopmbeng et al. (2012) assessed six artificial media in vitro to determine the growth

characteristics of the pathogen P. colocasiae Racib. After 7 days, colony diameter was

highest on v6 juice agar (64 mm), followed by V8 m juice agar (57 mm), onion agar (55

mm), V8 juice agar (54 mm) and potato dextrose agar (54 mm). Sahu et al. (2000) studied

different media to determine the most suitable medium for the growth of P. colocasiae

The highest linear mycelial growth was observed in papaya dextrose agar medium

followed by potato dextrose agar. Flores (2013) reported that Phytophthora genus has

been a group whose isolation and conservation is laborious and the work on search of

better options for both mycelial growth as well as sporulation for different isolates of

Phytophthora is a continuous process.

2.2 Isolation of antagonists and their potential

Plotnikova (1977) observed the presence of mycolytic bacteria in cow manure.

The extract of cow dung compost showed the presence of bacterial isolates which

inhibited the mycelial growth of Fusarium oxysporum f.sp. cucumerinum and

Helminthosporium sigmoideum (Kai et al. 1990). Czaczyk et al. (2000) isolated four

strains of Bacillus from cow dung compost. All the strains were reported to possess

strong inhibition properties against the mycelial growth of Rhizoctonia solani, Bipolaris

sorokiniana, Sclerotinia sclerotiorum, Trichothecium roseum, Fusarium solani and F.

oxysporum and recorded 56.2-71.0 per cent inhibition of these pathogens.

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Chung et al. (2000) isolated Paenibacillus koreensis from compost and observed

the antifungal activity against Fusarium oxysporum, Colletotrichum lagenarium,

Sclerotinia sclerotiorum, Botrytis cinerea and Rhizoctonia solani.

Quarles (2001) revealed that compost tea was rich source of nutrients and

microorganisms. These organisms were inhibitory to soil borne pathogens. Aspergillus

niger, Trichoderma harzianum, Bacillus cereus and B. subtilis were the major microbes

in cow dung compost. When these microbes were cocultured with the seedling blight

inducing pathogens such as Sclerotium rolfsii, F. oxysporum, Pythium aphanidermatum,

Helminthosporium maydis and R. solani, the mycelial growth of all tested pathogenic

fungi was inhibited to the tune of 40.0-57.8 and 35.5-53.3 per cent, respectively by B.

subtilis and B. cereus (Muhammad and Amusa 2003). Streptosporangium pseudovulgare

– an actinomycete caused the complete inhibition of mycelium of Lasiodiplodia

theobromae, a causal agent of rot of guava (Garg et al. 2003). Garg et al. (2004) isolated

an actinomycete from compost and found inhibitory to Colletotrichum gloeosporioides.

Raja et al. (2004) reported the presence of large number of bacteria in animal

excreta viz. Pseudomonas, Bacillus, Serratia, Flavobacterium and Streptomyces; majority

of which had the capacity to degrade cellulose, hemicelluloses and pectin, quickly

colonized the seed and induced systemic resistance. Velazquez et al. (2004) recovered the

xylan-degrading sporulated bacterium from fresh and old cow dung. The organism was

identified as Paenibacillus favisporus. Edward and Arancon (2004) reported the

antifungal activity of actinomycetous isolate obtained from vermicompost against

Pythium and Fusarium. Burkholderia cepacia (F-66) isolated from compost showed

mycelial inhibition of R. solani (Quan et al. 2005).

Charest et al. (2005) observed the presence of two bacteria Pseudomonas

aeruginosa and Rhizobium radiobacter in cow dung manure. Both bacterial isolates were

evaluated against Pythium ultimum. The fungal inhibition was increased 2-3 per cent by

R. radiobacter. Microbes present in compost protected the cucumber seedlings against

damping off caused by Pythium aphanidermatum (Larbi 2006). Prabhu (2006) reported

the presence of large number of plant growth promoting micro organisms in coconut leaf

vermiwash. Dogra (2006) evaluated the antifungal potential of bacterial isolates present

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in panchgavya against S. rolfsii, R. solani and S. sclerotiorum and reported 97-100 per

cent inhibition in the mycelial growth of pathogens. Swaminathan et al. (2007) observed

the presence of naturally occurring beneficial micro-organisms predominantly lactic acid

bacteria, yeast, actinomycetes, photosynthetic bacteria and certain fungi in panchgavya.

Khaing et al. (2008) reported the presence of ten species of beneficial microbes

such as Serratia marcescens, Bacillus megaterium, Azotobacter chroococcum,

Pseudomonas medocina and Flavobacterium spp. in vermiwash. Species of Bacillus,

Serratia, Pseudomonas and actinomycetes were obtained from panchgavya and evaluated

for their antifungal potential against soil borne pathogens viz. S. rolfsii, F. oxysporum, F.

solani and R. solani (Ashlesha and Sugha 2008). Maximum inhibition (99.0%) was

possessed by Serratia followed by species of Bacillus (72.7-99.0%) and actinomycetes

(48.6-99.0%) against all the test pathogens. Several phosphate solubilizing bacteria (PSB)

with lytic enzyme activity (proteases, amylases, phosphatases) were obtained from

vermiwash and also exhibited antifungal properties against soil borne pathogens

(Zambare et al. 2008). Kerkeni et al. (2008) isolated the bacterial cultures from animal

manure compost extract and evaluated these against F. oxysporum f.sp. radicilycopersici

causal agent of crown and root rot of tomato. Out of 14 isolates screened, 8 isolates

inhibited the mycelial growth of pathogen by 8-47 per cent. The effective isolates were

Chryseomonas luteola, Serratia liquifaciens and Aeromonas hydrophila.

Bacillus thermocloacae found in compost showed antifungal activity against

Fusarium (Niisawa et al. 2008). Meenatchi et al. (2009) observed the appearance of

beneficial bacteria, fungi and actinomycetous population in vermicompost. Naik and

Sreenivasa (2009) studied the presence of bacterial isolates in panchgavya which resulted

in increased seed germination (99%), seedling length and vigour in wheat. Beejamrutha

exhibited the presence of several beneficial microorganisms (Sreenivasa et al. 2009).

Raoudha et al. (2009) investigated the effect of bacterial isolates from compost amended

with solid olive mill wastes against Pythium aphanidermatum. Maximum inhibition was

obtained by B. subtilis (38%) followed by B. thuringiensis (37%), P. fluorescens (35%)

and P. pseudoalcaligenes (34%). Six bacterial strains isolated from compost showed

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antifungal properties against soil borne pathogens (Abdel et al. 2010). Gopal et al. (2010)

reported that P. fluorescens was predominantly present in coconut leaf vermiwash.

Actinomycetes present in cow dung compost possessed antimicrobial activity against

fifty three pathogens (Pinto et al. 2010). Sinha et al. (2010) documented the presence of

nitrogen fixing and phosphate solubilizing bacteria, Actinomycetes and mycorrhizal fungi

in vermicompost and vermiwash which showed antifungal activity against soil borne

pathogens. Thakur (2010) isolated fifty three bacteria from vermiwash and screened in

vitro for various plant growth promoting traits. Among 53 bacterial isolates tested, only

four showed antifungal activity against S. rolfsii, F. oxysporum and F. solani. Bacterial

isolates were found to be the species of Pseudomonas, Bacillus, Alcaligenes and

Micrococcus. Sreenivasa and Naik (2011) exhibited the presence of beneficial

microorganisms in panchgavya and beejamrutha which resulted in improved seed

germination, seedling length and vigour in wheat and soybean. Sook et al. (2011)

screened multifunctional bacteria with biocontrol and biofertilizing effects, identified

three Bacillus strains (BS11-1, BS11-2, BS11-3) with biological control and biofertilizing

effects. These strains exhibited antifungal activities against phytopathogenic fungi,

Botrytis cinerea, Cylindrocarpon destructans, F. oxysporum, R. solani, and P. capsici.

All these strains also produced IAA and siderophore depending on culture time and

produced a visible clear zone on agar plate containing 0.5 per cent carboxylmethyl

cellulose as a carbon source. Tan et al. (2013) evaluated Bacillus amyloliquefacien, CM2

and T5 isolated from the roots of tomato seedlings. Both these strains showed strong

biocontrol and growth promotion effects in tomato seedlings after treating both seedlings

and soils. The disease incidence was recorded to be reduced by 70.1 and 79.4 per cent by

CM2 and T5, respectively.

2.3 Use of ITK based and other organic inputs in vitro and in vivo

2.3.1 Himsol, matkakhad, panchgavya, vermiwash, biospray

Antifungal activity among various organic composts has been reported by various

workers against soil borne and foliar pathogens. Aqueous extracts of vermicompost and

organic compost inhibited the mycelial growth of B. cinerea, S. sclerotiorum, S. rolfsii, R.

solani and F. oxysporum f.sp. lycopersici in vitro (Nakasone et al. 1999).

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Sugha (2005) evaluated the antifungal potential of panchgavya against R. solani,

S. rolfsii, F. solani, S. sclerotiorum and Phytophthora colocasiae and advocated that the

mycelial bits dipped for 6 hours in panchgavya caused complete suppression of mycelial

growth of R. solani and the growth inhibition ranged between 88.1-92.3 per cent in other

pathogens. Dogra (2006) observed the antifungal activity of panchgavya against major

soil borne pathogens viz. F. solani f.sp. pisi, R. solani, S. rolfsii and S. sclerotiorum.

Mycelial bits dipped for 12 hours in panchgavya caused more than 90 per cent inhibition

of F. oxysporum f.sp. pisi and F. solani f.sp. pisi and 100 per cent inhibition of S. rolfsii,

S. sclerotiorum and R. solani.

Basak and Lee (2005) studied the efficacy and in vitro activities of cow urine and

dung for controlling wilt caused by F. oxysporum f.sp. cucumerinum of cucumber and F.

solani f.sp. cucurbitae. Cow dung solution showed 80-84 per cent inhibition of wilt

pathogens and cow urine showed 100 per cent inhibition of wilt pathogens. Fresh cow

dung, urine, milk and cow dung based preparations namely cow dung slurry, dried

powder and ash were evaluated against R. solani causing damping-off of okra and root

rot of pea pathogens. Complete inhibition in mycelial growth was obtained by amending

potato dextrose agar with cow dung and cow dung ash @ 5 g/100 ml medium followed

by cow dung powder (0.5 mm radial mycelial growth) (Ashlesha et al. 2009). Out of

twelve organic inputs tested, eight inputs viz. himsol, matkakhad, agnihotra ash + cow

urine, panchgavya, vermicompost, cow pat pit compost, NADEP compost and

biodynamic compost showed 60.2-100 per cent inhibition in mycelial growth of S.

sclerotiorum without autoclaving (Shalika 2009).

Sinha et al. (2010) studied the antifungal properties of vermicompost and

vermiwash against soil borne pathogens (P. ultimum, R. solani and Fusarium sp.) and

recorded 51-72 per cent inhibition in mycelial growth of pathogens. Sang et al. (2010)

reported the reduction in mycelial growth of P. capsici and Colletotrichum coccodes in

pepper and C. orbiculare in cucumber by water extracts of compost. Sathasivam et al.

(2010) analyzed the antibacterial and antifungal activity of cow urine distillate against

Pseudomonas aeruginosa, Klebsiella pneumoniae, Aspergillus flavus and A. niger.

Joseph and Sankarganesh (2011) studied the antifungal activity of panchgavya and cow

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urine against soil borne pathogens. Sreenivasa and Naik (2011) observed 92.1 and 57.3

per cent inhibition in mycelial growth of Fusarium sp. at 15 and 20 per cent

concentrations of cow urine in vitro. Pane et al. (2012) evaluated different compost teas

for the control of three tomato pathogens; Alternaria alternata, Botrytis cinerea and

Pyrenochaeta lycopersici and found that direct application of teas on tomato plants

significantly reduced disease symptoms caused by above pathogens. Chadha et al. (2012)

investigated efficacy of some of vedic krishi inputs, viz. panchgavya, vermiwash,

compost tea, matkakhad, beejamrit and jiwamrit for management of various plant

diseases under organic farming conditions. Panchgavya was found to be the most

effective (88.9%) in controlling the stalk rot of cauliflower while beejamrit was the most

effective as seed treatment and recorded 92 per cent seed germination of pea compared to

56 per cent in control. Compost tea, matkakhad and jeevamrit as foliar sprays also proved

to be quite effective against various foliar plant pathogens and enhancing the productivity

of different crops.

2.3.2 Fresh and fermented cow products

Earlier workers have also reported the efficacy of various cow products against

several diseases. Jayashree et al. (1999) tested butter milk, plant extracts and derivatives

for their efficacy in controlling pumpkin yellow vein mosaic virus in pumpkin. The only

animal product tested i.e. buttermilk reduced virus transmission effectively. Arun et al.

(2004) reported effectiveness of raw milk in reducing the severity of sorghum downy

mildew effectively. The antifungal activity of buttermilk is due to the lactic acid bacteria

that produced antifungal metabolites such as proteinaceous compounds and fatty acids

(Schniirer and Magnusson 2005). Diniz et al. ( 2006) exlpored the efficacy of crude cow

milk diluted in water (20%, v/v) as an alternative product to manage tomato late blight

caused by P. infestans and found that it did not reduce the disease. It was postulated that

diluted cow milk (20%) could also control P. infestans, however, at this concentration it

did not reduce the severity of tomato late blight (Diniz et al. 2006). Kurosaki et al.

(2007); Badadani et al. (2007) observed that the antimicrobial activity of cow urine may

be attributed to the presence of inorganic phosphorus, dimethylamine, amino acids and

peptides. Kutywayo et al. (2009) reported fermented cow urine at concentrations of 0.1,

0.5 and 100 per cent as more effective than the conventional fungicides. Shwetha and

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Hegde (2012) concluded that cow urine inhibited completely the mycelial growth of S.

rolfsii causing wilt of Stevia rebaudiana. Harender and Sharma (2013) investigated bio

efficacy of aqueous (BF-1) and cow urine based bio formulations (BF-II) against grey

mold of strawberry and found BF-II as more effective in mycelial growth inhibition

(95.4%) compared to BF-I (82.0%). BF-II resulted in 85.9 per cent reduction in the

incidence of grey mould and 81.4 per cent increase in yield compared to untreated

control.

Kumar et al. (2013) found all the animal products to be effective for management

of Rhizoctonia web blight of urdbean through botanicals and animal products. However,

among animal products, cow urine revealed highest reduction in disease severity (69.6%),

maximum increase grain yield (33.1%) as well as maximum 1000-grain weight (49.7%)

as compared to control.

2.3.3 Urine from different cattle.

Cattle urine @ 30 per cent was efficient on disease control including powdery

mildew of okra and has no phytotoxicity on tested plants as reported by Broek et al.

(2002). Selvi et al. (2008) tested sheep urine, buffalo urine, goat dung and hen litter for

their efficacy in controlling rice brown leaf spot caused by Helminthosporium oryzae

(Cochliobolus miyabeanus). Among the animal excrements tested, application of sheep

urine (20%) also showed appreciable increase in the biometric characters of rice followed

by buffalo urine (20%) and recorded the maximum yield parameters. Raja (2009) studied

the effect of quantity and time of buffalo urine application to control sheath blight disease

of rice caused by R. solani. The disease was very effectively controlled with buffalo urine

applied once at the panicle-differentiation stage followed by booting stage and to a lesser

extent at the heading growth stage. These treatments also resulted in significantly higher

yield as compared with the inoculated check. Venkataramana et al. (2011) emphasized

the need to find out some non-toxic biodegradable natural products to control diseases.

This induction resistance of plants to pathogens by using phyto-extracts in cow urine

(animal by-product) is one of the potential areas of research. A suitable concentration of

cow urine extracts of certain botanicals on foliar disease management in mulberry was

studied and recorded significant reduction in disease severity.

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2.4 Use of bioagents

Although much biological eradication of plant pathogens takes place in nature,

efforts to control plant diseases by introducing antagonistic organisms into the milieu of

plant-pathogenic organisms have not been successful, since most introduced organisms

cannot maintain themselves indefinitely in their new environment. A number of bio-

control agents like Trichoderma spp., Gliocladium spp., Bacillus subtilis, Aspergillus

niger, Azotobacter chroococcum, Azospirillum lipoforum, Psuedomonas fluorescens etc.

have been exploited in the management of major plant diseases.

Dennis and Webester (1971) found that many isolates of Trichoderma spp.

produced volatile and non-volatile antibiotics active against wide range of fungi. T.

harzianum has been recognised as a strong mycoparasite against soil borne pathogens

such as R. solani, S. rolfsii and F. oxysporum (Papavizas 1985; Chet 1987). Singh and

Sekhon (1990) noticed antagonistic activity of T. viride against R. solani in dual culture

and checked the development of black scurf on potato tubers in greenhouse. Strong

antagonism by Trichoderma spp. against F. oxysporum f.sp. lycopersici and F.

oxysporum. sp. radicis has been reported (Monaco et al.1991).

Trichoderma and Gliocladium gave best control of pathogens of pea mainly R.

solani, F. solani and S. sclerotiorum (Lacicowa and Pieta 1994). Singh (1998) confirmed

that T. harzianum showed strong mycoparasitism and covered 100 per cent colony

growth of S. sclerotiorum. T. harzianum and T. viride were found to decrease the root rot

caused by R. solani in bell pepper plants upto 70.9 per cent (Gaikward and Nimbalkar

2003). Dikshit et al. (2004) revealed antagonistic properties of Paclobutrazol- commercial

biological control agent against Phytophthora spp. causing buckeye rot. Nine isolates of

Trichoderma spp. were screened for their ability to inhibit soil borne fungal pathogens of

chickpea viz., R. solani, S. rolfsii and F. oxysporum f.sp. ciceri. Among these, T.

harzianum showed 72.1 and 59.9 per cent mycelial inhibition of R. solani and S. rolfsii

whereas T. virens exhibited 86.6 per cent inhibition of F. oxysporum f.sp. ciceri (Rudresh

et al. 2005). Srivastava et al. (2006) conducted studies on the effect of seed treatment

with T. viride @ 4 g/ha +soil application of farm yard manure against soil borne

pathogens (Rhizoctonia, Pythium and Fusarium ) of cauliflower and observed 31 per cent

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increase in germination and 65 per cent decrease in disease. The antagonistic activity of

T. virens, T, viride, T. harzianum, T. koningii, Pseudomonas fluorescens and B. subtilis

was evaluated against F. solani and R. solani causing root rot of sage (Mallesh et al.

2008). Out of these bioagents, T. viride provided maximum inhibition (94.4%) of F.

solani and R. solani.

Shashidhara et al. (2008) reported the effectiveness of antagonistic microbes viz.,

Bacillus sp., Pseudomonas sp., Trichoderma viride and T. harzianum against

Phytophthora capsici. T. viride provided maximum inhibition (72.5%) of the pathogen. T.

harzianum showed 82.8 per cent of F. oxysporum f.sp. cumini followed by T. viride with

74 per cent inhibition in mycelial growth under in vitro conditions (Deepak et al. 2009).

Pandey et al. (2011) demonstrated the antagonistic activity of T. virens and T. harzianum

against S. sclerotiorum, F. solani, R. solani and S. rolfsii causing 62.7-69.1 per cent

inhibition in mycelial growth of pathogens. Isolates of T. viride, T. harzianum and T.

pseudokoningii caused 64.4-65.6 per cent inhibition in mycelial growth of Phytophthora

capsici of black pepper (Mathew et al. 2011).

Sankari et al. (2011) revealed the dual effect of Azospirillum EPS

(exopolysaccharides) on the enhancement of host plant growth as well as biocontrol

against P. oryzae in upland rice. Gaigole et al. (2011) reported that several strains of

Trichoderma species were found to be effective against various soil borne plant

pathogenic fungi under greenhouse and field conditions. Ashlesha (2012) found that T.

harzianum (JMA-4) was more efficient in inhibiting the growth of capsicum pathogens

causing 82.82 per cent inhibition followed by T. koningii (DMA-8) and T. viride (H3). Pre

treatment with bioagents T. harzianum, T. viride (Kan.), A. niger AN-27 and P.

fluorescens provided induced resistance in plants against F. oxysporum f.sp. lycopersici

and resulted in reduction in disease incidence from 100 to 7.69 per cent (Rajik et al.

2012). Alwathnani and Perveen (2012) studied biological control of Fusarium wilt of

tomato by antagonist fungi and cyanobacteria and showed that Aspergillus niger,

Penicillium citrinum, Penicillium sp. and T. harzianum inhibited the radial colony growth

of the test pathogen.

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Chowdappa et al. (2013) reported the efficacy of Bacillus subtilis OTPB1 and T.

harzianum OTPB3 in inducing systemic resistance in tomato seedling against early and

late blight. Adhikari et al. (2013) studied the antagonistic properties of rhizobacterial

isolates isolated from different vegetables including tomato against R. solani. Among

them, P. fluorescens isolate PF8 and PF7 inhibited the mycelial growth of R. solani (72.05

and 68.25%) in dual culture method.

2.5 Use of botanicals and crude extracts

The presence of antifungal components in higher plants have long been

recognized as an important factor for disease resistance (Mahadevan 1982). Such

components being biodegradable and selective in their toxicity are considered valuable in

controlling some plant diseases (Singh and Dwivedi 1987). Michael et al. (1985) noticed

the inhibition of R. solani with aqueous extract of Vitex negundo. Kaushal and Paul

(1989) studied inhibitory effects of some plant extracts (Cannabis sativa, Pinus

longifolia, Eupatorium sp. and Lantana indica) on some legume pathogens and found

that all the plant extracts inhibited Colletotrichum truncatum and L. indica was most

effective. Tiwari and Nayak (1991) observed that extract of Ocimum sanctum was

effective in reducing the growth of R. solani both in vitro and in vivo. The antifungal

activity of Ocimum sanctum, Vitex negundo, Lantana indica and Azadirachta indica

against Macrophomina phaseolina and F. oxysporum f.sp. tracheiphilum causing

charcoal rot of cow pea was studied by Ushamalini et al. (1997).

Shivpuri et al. (1997) reported the toxicity of ethanol leaf extracts of neem and

datura against F. oxysporum and R. solani in vitro. Sharma and Kapoor (1999) evaluated

plant extracts of Saussurea lappa, Lantana camara, wheat and garlic for control of S.

sclerotiorum and reported that S. lappa and L. camara were most inhibitory to pathogen.

Leaf extracts of Datura stramonium, O. sanctum and A. indica caused more than 94.0 per

cent inhibition as well as reduced production of sclerotia of S. sclerotiorum causing stem

rot of mustard (Shivpuri and Gupta 2001). Sharma et al. (2003) recorded that seed

treatment with datura and neem extracts showed good seed germination, seedling vigour

and least mortality due to F. oxysporum f.sp. pisi, R. solani, Macrophomina phaseolina

and Alternaria alternata. Owalade et al. (2003) observed significant control of

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Colletotrichum capsici on cowpea and Fusarium moniliforme on maize using the crude

extracts from the leaves of Ocimum gratissium. Leaf extract of Maesa lanceolata was

found effective against R. solani, F. oxysporum, S. rolfsii, Aspergillus niger and P.

ultimum in vitro (Okemo et al. 2003).

The aqueous and ethanolic extracts of Melia azedarach were studied as potential

antifungal agents for F. oxysporum, F. solani and S. sclerotiorum. Ethanolic extract was

highly effective on all test fungi with inhibitory concentrations ranging from 0.5 to 25

mg/ml (Carpinella et al. 2003). The fungicidal properties of extracts from A. indica, D.

stramonium, O. sanctum, M. azedarach and Cuscuta reflexa against Colletotrichum

capsici were studied in vitro (Sinha et al. 2004). The radial growth of C. capsici was

lowest (30.9 mm) with O. sanctum compared to control (71.4 mm). Tiwari et al. (2004)

evaluated 213 plant extracts against S. rolfsii. Out of these, extracts of Ranunculus

sclerotus, Aloe vera, Murraya paniculata, Colocasia sp. and Datura metel were found

effective against the pathogen. Liu et al. (2004) screened ethanolic extracts of 16 plant

species for their antifungal activity against Colletotrichum musarum, F. oxysporum,

Alternaria alternata and Botrytis cinerea. Among 16 plant extracts, Euphorbia hirta,

Myrica rubra and Rhodomyrtus tomentosa exhibited 60 per cent inhibition in mycelial

growth of all the pathogens. Methanol extracts of fresh materials of 183 plants were

tested for in vivo antifungal activity against Magnaporthe grisea, Corticium sasakii,

Botrytis cinerea, Phytophthora sp., Puccinia recondita and Erysiphe graminis f.sp.

hordei by Kim et al. (2004) and 33 plant extracts showed more than 90 per cent disease

control in all the cases. Meena and Paul (2005) studied aqueous extracts of 10 plants

(Melia azedarach, Eupatorium odoratum, E. adenophorum, Cannabis sativa, Ranunculus

muricatus, O. sanctum, L. camara, Vitex negundo, Camellia sinensis and D. stramonium)

against F. solani f.sp. pisi, F. oxysporum f.sp. pisi, R. solani, S. sclerotiorum and Phoma

medicaginis var. pinodella. R. muricatus completely inhibited the growth of R. solani, S.

sclerotiorum and P. medicaginis while E. adenophorum caused 72.2 per cent inhibition

of F. solani and F. oxysporum. Rodriguez et al. (2005) investigated the antifungal

efficacy of leaf pulp of Aloe vera against R. solani, F. oxysporum and C. coccodes

isolated from bell pepper and observed 8.1, 2.7 and 4.3 cm of inhibition zones,

respectively. Yadav et al. (2005) found that 20 per cent extract of Datura stramonium

gave 44.8 per cent growth inhibition of R. solani.

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Zhang et al. (2006) evaluated the extracts of tea leaves against Colletotrichum

camelliae and recorded 75 per cent inhibition in mycelial growth of pathogen when PDA

medium was amended @ 25 mg/ml. The aqueous extracts of Terminalia arjuna (Roxb.),

Mangifera indica and Azadirachta indica were tested for their antifungal activity against

Fusarium solani by Irum et al. (2006). All the extracts exhibited significant reduction in

radial growth of pathogen with 74.0, 67.0 and 54.0 per cent inhibition caused by T.

arjuna, M. indica and A. indica, respectively. Farzaneh et al. (2006) studied the effect of

extracts of aerial parts of Artemisia sieberi. The extracts were obtained through

hydrodistillation and evaluated against soil borne pathogens (R. solani, F. solani and F.

moniliforme). Distillates showed strong antifungal activity against R. solani (75%) and

intermediate (65.7%) against other pathogens. Huang et al. (2006) screened extracts of 10

medicinal plants against P. capsici, B. cinerea, Verticillium dahliae, F. oxysporum and S.

sclerotiorum. The aqueous extracts of Eugenia caryophyllata, Coptis chinensis and

Glycyrrhiza uralensis were found most effective against all the pathogens.

Dar et al. (2007) investigated the inhibitory effect of the extracts of Allium

sativum, D. stramonium, Mentha arvensis and Thuja orientalis at 25-50 per cent

concentration on S. sclerotiorum by poisoned food technique. The A. sativum extract

resulted in the highest reduction in dry mycelial weight (81.2%) and sclerotial production

(65.3%) over the control as reported by Kekuda et al. (2007). Jarald et al. (2008) reported

the anti-microbial property of cow urine and its distillate against soil borne pathogens and

found fresh cow urine to be more effective than its distillate. Aqueous and ethanol

extracts of A. indica and M. azedarach were evaluated against two pathogenic fungi of

tomato; A. solani and F. oxysporum (Hassanein et al. 2008). At 10 per cent concentration,

aqueous extracts of A. indica and M. azedarach provided 70.5 and 15.7 per cent

inhibition of A. solani and 100 and 16.5 per cent inhibition of F. oxysporum, respectively.

Shashidhara et al. (2008) tested the effectiveness of Clerodendron inerme, Duranta

plumeri, Eupatorium sp., A. sativum, V. negundo, L. camara and A. indica against P.

capsici in black pepper. Among these, duranta and garlic (10%) provided 35.5 and 26.6

per cent 16 mycelial inhibition of P. capsici, respectively. Aqueous, petroleum ether and

methanol extracts of fenugreek (3%) expressed the strongest inhibition (71.4%) against

F. graminearum, B. cinerea, Alternaria sp. and R. solani (Haouala et al. 2008). Mallesh

et al. (2008) evaluated various organic amendments against F. solani and R. solani and

found that lowest incidence of disease (18.75% and 31.25%) was recorded in neem cake

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at 5 and 2 per cent concentrations followed by pongamia cake (37.5 and 43.75%).

Bhattarai and Shrestha (2009) revealed that the aqueous and ethanolic extracts of E.

adenophorum (50 and 10% concentration) were found highly effective against F.

oxysporum, F. moniliforme and Aspergillus niger. The aqueous extracts of 46 plants were

screened for antifungal activity against species of Fusarium (Satish et al. 2009). The

extracts of Emblica officinalis, Eucalyptus globules and Punica granatum were found

inhibitory to fungi. Solvent extracts (petroleum ether, methanol and ethanol) of

Polyalthia longifolia and Murraya koenigii exhibited strong antifungal potential. Roat et

al. (2009) studied the inhibitory effects of some plant extracts (Diospyros cordifolia, D.

stramonium, Cassia fistula, Solanum indicum, Santalum album, Annosa sqamosa and

Justicia adhatoda) in vitro and in vivo against fruit rot of chilli incited by C. capsici. D.

cordifolia (bitter temru) fruit and D. stramonium (datura) leaves inhibited the maximum

mycelial growth and spore germination of C. capsici. Isopropanol alcohol-1 extract of

Melia azedarach and aqueous extract of O. basilicum and V. negundo completely

inhibited the growth of S. sclerotiorum (Shalika 2009). In vitro studies conducted by

Anand and Bhaskaran (2009) indicated that leaf extracts of Abrus precatorius, Aegle

marmelos and Eupatorium sp. showed highest inhibition of spore germination and

mycelial growth of C. capsici and A. alternata. Among 44 plant extracts tested, A.

sativum gave strong inhibition i.e. 5.75 mm at 10 ppm concentration followed by A. cepa

and Emblica officinalis i.e. 3.25 mm each against R. solani isolated from rice (Sehajpal et

al. 2009). Zang et al. (2009) studied the antifungal efficacy of Ocimum basilicum var.

pilosum against B.s cinerea, F. oxysporum, S. sclerotiorum, F. solani and Phytophthora

capsici and found it most inhibitory to all the pathogens. Shahnazdawar et al. (2010)

studied the effect of Datura alba and Cynodon dactylon against Macrophomina

phaseolina and R. solani in okra and cowpea. Both pathogens were completely

suppressed by D. alba extract. Maximum growth suppression was observed in A. flavus

(7.06 mm in diameter). Water extract and distillate of O. sanctum and M. koenigii showed

optimum antifungal activity against all the pathogens. Methanol extracts of Lawsonia

inermis, Withania somnifera, Datura metel, D. stramonium and Bauhinia racemosa were

evaluated by Khan and Nasreen (2010) against C. capsici, C. lindemuthianum, F.

moniliforme, R. solani, F. oxysporum and Alternaria alternata. Among these, L. inermis

exhibited maximum inhibition in mycelial growth of F. moniliforme (87.7%) followed by

C. capsici (84.4%), F. oxysporum (83.5%) and R. solani (81.10%).

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Goel et al. (2011) studied the antifungal activity of hexane, ethyl acetate and

methanol extracts of Parmelia reticulata against S. rolfsii, R. solani, F. udum and P.

aphanidermatum. Maximum inhibition was exhibited by hexane and ethyl acetate

extracts against all pathogens. Extracts of L. camara, neem cake extract, cow urine,

Urtica parviflora, Sapium sp., Ligustrum nepalensi, Eucalyptus spp. and Azadirachta

were found most promising for the management of pre- emergence damping –off of

tomato. In case of post emergence damping-off Curcuma longa and Thuja compacta

were found to be most effective (Hooda et al. 2011). Alemu et al. (2013) evaluated the

antibacterial activites of aqueous and solvent extracts of five invasive alien species

(Eichhorina crassipes, Mimosa diplotricha, L. camara and Prosopis jullifora) against R.

solanacearum and found that most of the plant extracts exhibited significant inhibition of

bacterial growth. Aqueous extracts of E. crassipes provided the highest inhibition zone

(26 mm).

Antifungal activity of M. azedarach against F. oxysporum and A. solani was

suggested to be due to presence of alkaloids, steroids, flavanoids (Rahman and Gray

2005; Hassanein et al. 2008) and of Eupatorium sp. against P. capsici may be due to

carotene, flavones glycoside and ranuncoside (Shashidhara et al. 2008; Hussain et al.

2011). Zhang et al. (2006) reported inhibition effect of leaf juice extracts of E.

adenophorum on P. infestans. The petroleum ether extract of E. adenophorum recorded

the highest (44.42%) inhibitory activity against the pathogen. Sterilized and non-

sterilized leaf juice of E. adenophorum exhibited more than 50 per cent inhibition, which

increased to 95 per cent against P. infestans when mixed with 25 per cent metalaxyl.

Yadav and Yadav (2009) reported the highest fungitoxic activity of 6 plant extracts

against P. parasitica var. piperina at 30 per cent concentration. Maximum growth

inhibition of the pathogen was recorded with Aegle marmelos (88.3%) followed by

Murraya koenigii (82.6%), Lawsonia inermis (81.3%), Argemone mexicana (80.1%),

Catharanthus roseus (72.5%), and M. azedarach (68.7%).

Ashlesha et al. (2013) studied antifungal activity of cow urine distillates of local

botanicals M. azedarach, Eupatorium sp and others against major pathogens of bell

pepper including P. nicotianae at 0.5, 2.0, 4.0, 6.0, 8.0 and 10.0% concentrations in vitro.

They reported more than 98 per cent inhibition in mycelial growth of P. nicotianae at 10

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per cent concentration. Cow urine distillates of botanicals were found more inhibitory to

pathogens than cow urine distillate alone. Alemu et al. (2013) evaluated extracts of

botanicals on tomato plants at three time of applications (at the time of inoculation and 2

days before and after inoculation) and revealed that most of the treatment combinations

significantly reduced per cent disease severity index.

2.6 Use of oils and modified panchgavya

Garg (1974) reported that oils derived from Eupatorium triplinerua, Murraya sp.

and Eugenia heyneane were inhibitory to several fungi tested using agar diffusion

technique. Singh and Dwivedi (1987) evaluated various oils of different plant species

against Sclerotium rolfsii and found that oils from Eucalyptus globulus and Ocimum

canum were most effective in inhibiting the pathogen completely at 4000 ppm. Ramezani

et al. (2002) studied the effect of volatile oils from Eucalyptus citriodora and its major

constituent citronellol against rice pathogens and concluded that eucalyptus volatile oils

have potential for the suppression of phytopathogenic fungi. Sharma et al. (2003)

evaluated oils of Brassica juncea and Mentha piperita against seed borne pathogens of

pea and found that these two oils showed considerable antifungal activity.

Gwinn et al. (2010) studied the role of essential oils from 13 monarda herbages

for controlling of Rhizoctonia damping –off in tomato. Antifungal activities of essential

oils obtained from aerial parts of aromatic plants such as Origanum syriacum, Lavandula

stoechas and Rosmarinus officinallis were investigated against Botrytis cinerea.It was

found that oils cause considerable morphological degeneration of fungal hyphae (Soylu et

al. 2010). Sukanya et al. (2011) tested essential oils and found that pepper oil is most

effective against P. oryzae followed by coriander oil.

Panchgavya use can be traced back to times of great Indian epic 'Mahabharat' as

purification act of persons who committed misdeeds as per Hindu religion (Shastri 1982).

Munshi (1984) in his monograph on "Agriculture in ancient India" has given an account

of protection of crops from pests and diseases. The application of panchgavya amended

with carbendazim (MPG-modified panchgavya) was found effective in suppressing

seedling disease and wilt incidence of tomato both in pot culture and field studies

(Bhaskar 1994). Research on the management of panama disease of banana caused by

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Fusarium oxysporum f.sp. cubense, using modified panchagavya mixture (mixture of

cow milk, curd, ghee, dung and urine supplemented with yeast and common salt) was

reviewed by Jahagirdar et al. (2003). Dhama et al. (2013) highlighted that the use of cow

derived products has been mentioned in the "Vedas" and various researchers and

scientists have found these to be rich source of essential elements as well as minerals and

hormones. For this reason, the use of panchgavya (term used to describe five major

substances obtained from cow that include: cow's urine, dung, milk, curd and ghee) and

its products is gaining popularity. Panchgavya Therapy/Chikitsa (Cowpathy) has been

proposed as an alternate prophylactic and therapeutic approach.

2.7 Use of commercial products.

Babu et al. (2000) found potential antagonists of Alternaria solani with

suspension of Psuedomonas fluorescens strains as its application reduced leaf blight

disease within 48 hours of application. Besides, several other commercial formulations of

biocontrol agents have been tested for efficacy against late blight. Curiously, bacterial

cells were not directly responsible for the inhibition of the pathogen. A cell- free culture

extract contained metabolites that were active against P. infestans (Stephan et al. 2005).

Suppression of disease in tomato infected by Pythium ultimum with a biosurfactant

produced by Psuedomonas koreensis was investigated by Hultberg et al. (2010) and was

found significant in reducing the disease. In vitro inhibition of tomato Fusarium wilt by

zearalenone, secondary metabolite produced from a soil inhabiting fungus was reported

by Njue et al. (2012).

2.7.1 Use of resistance enhancer

BTH (Benzo (1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester) synthetic

chemical was reported to be active at priming for better induction of defense responses in

both plant cell cultures and intact plants and to supply protection in the field against

broad spectrum of diseases in various crops (Ryals et al. 1996). Khan et al. (2004)

observed systemic resistance induced by Trichoderma hamatum 382 in cucumber against

Phytophthora crown rot and leaf blight as that provided by a drench with

benzothiadiazole (BTH) or mefenoxam. Control of chickpea blight disease caused by

Didymella rabiei has been reported by Sharma et al. (2011) by mixing resistance inducer

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(BTH) and contact fungicide. Chowdappa et al. (2013) found the efficacy of Bacillus

subtilis OTPB1 and T. harzianum OTPB3 to induce systemic resistance in tomato plants

against early and late blight (Phytophthora infestans). Trichoderma spp. provided

induced resistance in plant against F. oxysporum f.sp. lycopersici resulting in declined

disease incidence from 100 to 7.69 per cent (Rajik et al. 2012).

2.8 Screening of germplasm/ varieties and susceptibility of tomato against the

disease

Lines showing resistant reaction under natural epiphytotic condition succumb to

inoculations under laboratory conditions. The resistance is available only in small-fruited

cherry type lines, which get eliminated to dilute in advance generations in the process of

breeding for desirable fruit size. Felix (1948) noted that all Lycopersicon spp. tested were

susceptible to the disease. Obrero and Aragaki (1965) reported that hybrid N-64 (STEP

390 HES 6578) was highly resistant when tested under in vitro conditions. They further

observed that resistant varieties required more zoospores and longer incubation period for

infection than susceptible ones. Rattan and Saini (1979) studied inheritance of resistance

to fruit rot in tomato in a cross between EC 54725, resistant to fruit rot and four highly

susceptible tomato commercial cultivars (Gola, Sioux, S12 and Lal Mani) and indicated

that EC 54725 carries a dominant gene imparting resistance to fruit rot. Cultivar Rossol

was found to be resistant to buckeye fruit rot in laboratory as well as under field

conditions (Perez et al. 1986).

Threja and Srivastava (1989) identified lines such as EC 129171/PI-2, EC128964,

EC129166, EC72901, EC 122962-1 and Hybrid 10 as resistant. Kohli et al. (1996)

exposed huge tomato germplasm to natural epiphytotics and found that none of the

varieties/lines was free from the disease though the lines EC174023, EC174041 and Sel

16 had good fruit size and tolerance to the disease. They also observed that resistance to

disease is confined to small cherry fruited lines having fruit weight lesser than 20 g. Out

of 220 genotypes comprising of exotic and indigenous lines of tomato under natural

epiphytotic revealed that incidence of disease was relatively higher in medium and large

fruited lines having a fruit weight of 41-80 g whereas a high level of resistance was

observed in small fruited lines having a fruit weight of less than 20 g (Kohli et al. 1996).

Dodan and Shyam (1996) found that the cultivar Ceresiformae exhibited a resistant

reaction at lower inoculum densities but a susceptible reaction at the highest inoculum

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density. Other tomato cultivars like Money Maker and Solan Gola were found to be

susceptible. Bijaya et al. (2002) screened 106 tomato cultivars and among them, KT-10

and KT-15 were the most promising. Joshi et al. (2004) screened 80 lines of tomato and

found that EC 129602 recorded the minimum (6.48%) buckeye rot incidence and rated as

moderately resistant under field conditions. Of the 73 genotypes evaluated, none was

found completely free from disease. Seven genotypes were rated as moderately resistant

and 47 as moderately susceptible (Joshi et al. 2005).

2.9 Integrated management of disease

Integrated disease management practices, which include use of cultural,

biological, chemical and resistance-breeding programme measures, effectively manage

the disease. Williams and Sheard (1943) recommended destruction of diseased fruits and

keeping the plants trimmed to avoid moist and stagnant air conditions. Plants should be

staked or tied to frames to avoid contact with soil (Wager 1935; Ramakrishnan and

Saumini 1947; Welch 1949). The practice of staking is the most effective mean of control

of this disease (Walker 1952). Bryant and Kreutzer (1945) suggested setting of plants on

ridges in irrigated soils under conditions where staking was not feasible. Mulching and

spraying the mulch with fungicide also reduced the disease (Welch 1949). Foliage and

fruits have to be removed upto 30 cm from ground level to control the disease (Sharma et

al. 1976b). An integrated approach consisting of spray of Dithane M-45 or Bordeux

mixture or captafol alongwith staking and removal of foliage and fruits upto 30 cm was

found to be most effective and economical (Sharma et al. 1976a; Thapa and Sharma

1978; Das and Mohanty 1987).

Combination of fungicide sprays, clipping lower leaves, weeding, and application

of polythene mulch to obstruct dispersal of soil borne inoculum of the pathogen and

removal of affected fruits increased yield and reduced disease incidence (Dodan et al.,

1994). Verma et al. (1994) while testing Dithane M-45 and Ridomil MZ-72 against P.

nicotianae var. parasitica and P. infestans on different tomato cultivars found that

cultivar Roma gave highest yield of quality fruits with Ridomil MZ-72 and highest seed

yield with Dithane M-45. The interaction effect of fungicide spray schedules and staking

on buckeye rot incidence indicated that staking had significant effect on the efficacy of

fungicide spray compared with no staking (Bhardwaj et al. 1995).

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Bhardwaj and Masand (1995) indicated that mulching increased the disease

incidence and affected tomato fruit yield and was attributed to increased soil moisture

conservation by mulch application. Ushamalini et al. (1997) found that wilt of cowpea

could be controlled either by seed treatment with T. viride and T. harzianum or soil

application of FYM and neem cake or seed treatment with leaf extract of A. indicum and

Delonix regia. Pine needle mulch and Rodimil MZ sprays on mulch and foliage reduced

the buckeye fruit rot incidence (Gupta et al. 1998). Handoro et al. (2001) revealed that

amendment of soil with organic manures was found significantly better in reducing the

white rot of pea as compared to the untreated control. Among the amendments, neemax,

FYM, horse stable manure and sheep manure resulted in 6.44, 7.43, 8.00 and 8.45 per

cent disease intensity, respectively. Burelle (2002) reviewed the non-chemical methods of

controlling tomato diseases by using resistant cultivars, applying optimum amount of

fertilizers, maintaining well drained soils, seed treatment, crop rotation, increasing soil

organic matter, soil solarization, sanitation and/or biological control agents.

Singh et al. (2004) evaluated four antagonists as seed, soil and combined seed and

soil treatments for the control of tomato wilt caused by F. oxysporum f.sp. lycopersici in

greenhouse. T. harzianum, T. viride and Gliocladium virens as seed treatment @10 g/kg

seed were effective in controlling seedling mortality up to 85 per cent. Sharma and

Deshpande (2006) found that seeds soaking with organics improved quality of seed and

also enhanced germination. The highest germination was recorded when the seeds were

soaked in vermiwash followed by cowdung and biogas slurry. The seed treatment with T.

viride along with soil application of FYM was found to be superior in controlling pre and

post emergence damping off of tomato (Usha and Satheesh 2007). T. viride proved more

effective and controlled Sclerotinia rot of rapeseed and mustard to the extent of 60.0 and

70.0 per cent compared to 40 and 60 per cent with T. harzianum in seed and spray

treatments, respectively (Singh 1998). Five biocontrol agents along with two fungicides

were applied as seed treatment, nursery drenching, seedling dip and foliar sprays against

pre and post emergence rots and foliar diseases of tomato. All treatments significantly

reduced pre and post emergence rots but foliar sprays of bioagents had no effect on the

incidence of these diseases (Hooda et al. 2008). Three modules (IPM, chemical and

organic) were tested for pest management in tomato. Out of three modules tested in

tomato, maximum severity of the disease was observed in organic module (> 6.8%)

followed by chemical (> 4.4%) and IPM module (> 2.1%) (Hooda et al. 2011).

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In controlling disease incidence, polythene mulch was found to be relevant as its

barrier like action obstructs the dispersal of the soil borne inoculum and contact of the

fruits with the soil. Effective control of fruit rot of tomato has also been reported by

Welch (1949) through application of straw mulch in combination with fungicide sprays.

Bhardwaj and Masand (1995) studied effect of mulching and irrigation schedules on

buckeye rot (P. nicotianae var. nicotianae) of tomato. It was concluded that the

application of light irrigation and ensuring optimum crop-water use were important in

reducing buckeye-rot. Soil application of T. viride decreased population of Fusarium in

wilt sick soil as reported by Jahagirdar et al. (2003) by considerably contributing towards

the good health of the plant. Mehta et al. (2010) studied effect of training methods and

mulching on growth, yield and fruit rot incidence in tomato. Amongst 8 treatment

combinations, the maximum plant height, harvest duration and fruit weight was obtained

in treatment combination L1M1 (single leader+ black plastic mulch), whereas highest

yield/plant was recorded in L2M1, i.e. double leader+ black plastic mulch. The incidence

of fruit rot was minimum in L1M1 (single leader+ black plastic mulch), closely followed

by L2M1 (double leader+ black plastic mulch) and L3M1 (triple leader+ black plastic

mulch). Shwetha and Hegde (2012) tested different bioagents, botanicals and

biorationals. Among them, T. harzianum, T. viride, Duranta repens and Eupatorium

odoratum were very effective and checked the disease completely up to 30 days after

planting.

2.9.1 Role of weather variables

Thareja et al. (1989) reported that maximum fruit infection under field conditions

occurs at a temperature range of 20-25 oC, RH > 60 per cent and high rainfall conditions.