research article phenotypic response of two garlic varieties...

Research ArticlePhenotypic Response of Two Garlic Varieties to DifferentNitrogen Fertilization Grown under Irrigation in SudanSavannah Ecological Zone of Nigeria

Magaji G Usman1 A S Fagam1 Rilwanu U Dayi2 and Zaharaddeen Isah1

1Department of Crop Production School of Agriculture and Agricultural TechnologyAbubakar Tafawa Balewa University (ATBU) PMB 0248 Bauchi Nigeria2Department of Agricultural Technology College of Agriculture Hassan Usman Katsina PolytechnicTafawa Balewa Way PMB 2052 Katsina State Nigeria

Correspondence should be addressed to Magaji G Usman magajiusman0gmailcom

Received 29 November 2015 Revised 12 March 2016 Accepted 17 April 2016

Academic Editor Iskender Tiryaki

Copyright copy 2016 Magaji G Usman et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

A study was conducted under irrigation during dry season at the Katsina State Irrigation Site AjiwaThe aim of the experiment wasto enhance the productivity of garlic through the choice of appropriate levels of nitrogenous fertilizer and suitable cultivar whichmaximizes yield The experiment consisted of two varieties (ex-kofa and ex-sokoto) and four levels of nitrogen (0 50 100 and150 kgNha) They were arranged in a randomized complete block design in three replications The variety ex-sokoto was foundsuperior to ex-kofa with respect to plant height number of leaves leaf area and days to maturity number of bulbs bulb diameterbulb weight and number of cloves per bulb cloves weight per bulb and fresh and cured bulb yield Application of 50 kgNhasignificantly increased plant height (cm) number of leaves per plant leaf area number of bulbs and the total yield of the garlicSignificant effects of interaction between variety and nitrogen on leaf area and number of cloves per bulb of the garlic were observedThe combination of ex-sokoto variety and 50 kgNha was found to increase garlic yield Maximum growth and yield could berealized using a combination of ex-sokoto variety and 50 kgNha at Ajiwa

1 Introduction

Garlic (Allium sativum L) belongs to the family Alliaceae Itis the secondmost widely used among cultivated alliums afteronion (Allium cepa) The crop consists of an undergroundbulb and above the ground vegetative part which consists ofthe leaves and flowers The rooting system is fibrous whilethe bulbs comprise small bulbils called cloves which are thevegetative propagating materials of the crop [1] Garlic is acold weather perennial crop with high nutrient and waterrequirement [2] The crop is grown under both rain-fed andirrigated conditions It gives good result when grown onfertile well-drained and sand or silt-loam soils with goodmoisture retaining properties Garlic ismainly used as a spiceseasoning and flavouring for foodstuff involving both greentops and bulbs due to its pungent flavour [3] Garlic nitrogenrequirement is 5N 4N and 3N at prebulbing bulbing

and postbulbing stages respectively [4] and it is considereddeficient in nitrogen with 4N 3N and 2N at earlyseason midseason and late season respectively [4]

India is one of the worldrsquos largest producers of garlic withan average yield of about 523 tonnes per hectare [5] Othergrowers are Spain Egypt Korean Republic Argentina ItalyChina and the United States According to [6] production ofgarlic stood at about 10 million tonnes per annum which isonly about 10 of the production of bulb onions The worldaverage yield of garlic is about 10 tha but can go up to 19 thaIn Nigeria the crop has been in cultivation for decades innorthern states such as Kano Sokoto Borno Bauchi JigawaKatsina and Zamfara [7]The sativum variety has a bulb withmany pure white or pink-blushed bulblets [8]

Plant growth characteristics can vary tremendously fromone location to another complicating variety selection[9] Significant variations were observed for various garlic

Hindawi Publishing CorporationInternational Journal of AgronomyVolume 2016 Article ID 2495828 9 pageshttpdxdoiorg10115520162495828

2 International Journal of Agronomy

characteristics such as the relative growth rate plant heightnumber of leaves leaf area and net assimilate rate [10ndash13]due to grown cultivars Recently [14] reported variations inplant vigour among six garlic genotypes tested with Egaseed1 and Sid 40 recorded the highest plant vigour comparedto the other varieties Earlier reports [3] showed that therewas significant difference in plant height among the testedvarieties Variety Tsedey 92 recorded the highest plant heightcompared to the local variety Rie at Tegahne irrigation siteGolgol Naele and Atsbi Womberta Wereda It was reportedin [15] that there was significant difference among 17 cultivarsof garlic in plant height in 1995 rainy and 1996 dry seasons(under irrigation) at Debre Zeit

Chemical fertilizers have becomewidely used in vegetableproduction in tropical areas particularly where they arereadily available It is well known that the use of fertilizerhelps in production and is somewhat a quick method forachieving maximum yield [16] Nitrogen is generally founddeficient in most of the African soils particularly in theareas where farmers practice intensive cultivation and growhigh yielding varieties [17] Availability of nitrogen is ofprime importance for growing plants as it is an integralpart of chlorophyll molecules which are responsible forphotosynthesis [18] A high rate of nitrogen induces growthforms high amount of proteins and by competence reducesanthocyanin synthesis because a high amount of aminoacids is destined to form proteins [19] Nitrogen is amongthe most important nutrient elements in garlic and othercrops and actively acts in numerous metabolic processesNitrogen supply was reported [20] to affect growth andassimilation rates in plant mainly by altering the size ofthe photosynthetic apparatus (leaf area) and it may alsoaffect leaf efficiency Nitrogen fertilizer increased the rate ofleaf appearance and the rate of leaf extension particularlyfor the first leaf following effects on tissue nitrogen Bulbgrowth also responded significantly to applied nitrogen [20]Increasing nitrogen rates to 100 kgNha resulted in longerleaves and greater number of leaves per plant [21] In anothertrial [2] the growth and yield parameters increased withincreasing nitrogen rates up to 150 kgNha However higherrates of nitrogen beyond 150 kg decreased growth and yield200 kgNha significantly increases the yield parameters likeneck thickness bulb diameter number of cloves per bulband fresh weight of 20 cloves [22] However at Samaru inNigeria [23] nitrogen application increased almost all growthand yield parameters of garlic significantly and themaximumyield of 15 tha was recorded with 90 kgNha Furthermore[24] recorded significant increase in bulb yield with theapplication of 75 kgNha while clove weight increased only at150 kgNha beyond which there was a significant reduction

The wide gap between present low yield and the poten-tial yield of garlic in Nigeria is an indication of severalconstraints that are limiting garlic production Some ofthese limiting factors are environmental While other fac-tors are due to agronomic or cultural practices Some ofthe major constraints include inadequate fertilizer weedschemicals storage and transportation facilities Howeverthe per-hectare yield of garlic can be increased by adoptingproper package of practices like timely planting proper

spacing and judicious application of irrigation water andbesides these balance application of nitrogen plays a vitalrole in the development of garlic [21] There is dearth ofinformation on garlic production in Nigeria except for someworks done at Samaru on spacing fertilizer and irrigationrequirements [24] Generally it is in view of this backgroundthat this study was undertaken with the aim of exploringopportunities to improve the productivity of garlic throughthe choice of appropriate levels of nitrogenous fertilizer andsuitable cultivar which maximizes yield The objectives wereto determine the influence of nitrogenous fertilizer on theperformance of two garlic varieties and their interactionsThe hypothesis for this work was as follows H

0there is no

significant variation between the two garlic varieties withrespect to their growth and yield performance and differentnitrogen fertilization does not affect the growth and yield ofgarlic

2 Materials and Methods

21 Site and Location Field experimentwas conducted underirrigation during 20102011 dry season at the Katsina StateIrrigation Site Ajiwa The site is approximately located at13∘011015840N and 7∘411015840E and 619m above sea level in the Sudansavannah ecological zone of Nigeria [26] The soil of theexperimental site was loamy soil A detail of the physio-chemical analysis of the soil was presented in Table 4 whilemeteorological data was presented in Table 5

22 Treatments and Experimental Design The treatmentsconsisted of factorial combination of two garlic varieties (ex-kofa and ex-sokoto) and four nitrogen rates (0 50 100 and150 kgNha) These were arranged in a randomized completeblock design and replicated three times The total area forthe experiment was 16m times 65m The field was furthermade into three replicates with 10m spacing between thereplicates Each replicate comprises 8 plots (each representinga treatment combination) with 05m spacing between theplots The experimental field was cleared ploughed andharrowed to pulverize the soil before making a plot of 15mtimes 15m as gross size in sunken appearance The gross plotsize was 225m2 and the net plot size was 1m2 The net plotwas ldquothe central area where observations were takenrdquo Thisis to avoid bias due to interference between plots The plotswere bounded by low bounds in order to retain the irrigationwaterTheuniforms inter- and intrarow spacing of 10 cmwereused Each gross size plot consists of 15 rows with 15 holes perrow and a total of 225 plants per plot and 100 per net plot(10 rows with 10 holes per row) The total plant populationwas 5400 plants during the experimental period The cropreceived an application of nitrogen fertilizer as urea (46)according to the treatments in two equal split doses A basaldose of half the nitrogen rate was applied and incorporated atsowing The second dose of the nitrogen was applied at fourweeks after sowing (4WAS) The fertilizer was incorporatedmanually using hand hoe

23 Experimental Material Local variety of garlic ex-kofais popularly grown around Kofa village in Kano State

International Journal of Agronomy 3

The matured bulb is globular in shape with white ldquoskinrdquo orouter covering The bulbs are medium in size and sealed upat the tip The ex-sokoto is also a local variety commonlygrown in Sokoto State The matured bulb is not completelyround The bulb has protruded cloves This variety is alsocalled Hyena Hoof These varieties were selected based ontheir high bulb yield and pungent flavour

24 Plant Husbandry The land preparation was carried outin the last week of December 2010 Planting was carriedout on December 30 in the 20102011 dry season A daybefore planting bulbs were separated into individual cloveswith only the large and healthy ones selected and soaked inwater overnight in order to remove the scale leaves coveringthe clove which enhanced rapid sprouting The basins werepreirrigated a day prior to planting Planting was donemanually on the prepared plots with one clove planted perstand The cloves were placed into the soil 2-3 cm deep withthe growing point upward and covered lightly with soil forconsolidationThe experimental field was irrigated by surfaceflooding method every three days during the early stagesof growth and later every four days Irrigation was stoppedtwo weeks before harvest to allow for uniform maturityWeeding was done manually using both handpicking andhoes weeding The weeding was carried out at 4 6 and 8weeks after sowing There was no observable incidence ofeither pest or disease attack on the crop throughout thegrowing period

25 Morphophysiological Parameters Characters assessedinclude plant height number of leaves leaf area and numberof days to 50 maturity matured bulb diameter individualbulb weight and number of cloves per bulb cloves weight perbulb fresh bulb yield and cured bulb yield (Table 1)

26 Data Analysis Results were analysed using SAS version93 computer software for all characters assessed [27] Leastsignificance difference (LSD) was used to separate the sig-nificantly different means and their interactions The meanvalues of the dependent and independent variables werealso subjected to correlation coefficients Association of thevarious characters with yield per plant and among themselveswas worked out at phenotypic level according to the methodgiven in [28]

3 Results

31 Garlic Varietal Response on Growth Characters Thevarieties differed significantly (119901 lt 005) at most stages ofgrowth in affecting the plant height number of leaves leafarea (Figures 1ndash3) and days to 50 maturity (Figure 4(a)) ofgarlic during the course of the study The variety ex-sokotoconsistently produced taller plants and grewmore leaves withgreater leaf area compared to ex-kofa The growth of theseparameters increases from 4WAS to 8WAS after which itdeclinesHowever ex-kofa took the highest number of days to50 maturity of the garlic plants compared to the ex-sokotovariety (Figure 4(a))

ex-kofaex-sokoto

R2= 09974

5 7 9 113Weeks after sowing

05

10152025303540

Plan

t hei

ght (

cm)

Figure 1 Significant (119901 lt 005) growth trend of garlic varieties at 46 8 and 10 weeks after sowing on plant height 1198772 is the goodness offit

ex-kofaex-sokoto


0

2

4

6

8

Num

ber o

f lea

ves

R2= 09373

Figure 2 Significant (119901 lt 005) growth trend of garlic varieties at4 6 8 and 10 weeks after sowing on number of leaves 1198772 is thegoodness of fit

Effect of interaction between variety andnitrogen rates onthe garlic leaf area at 6WAS differed significantly (119901 lt 005)during the study as shown in Figure 5 Increase in nitrogenrates from 0 to 50 kgNha significantly increased leaf areain ex-sokoto with no significant influence on ex-kofa Thesignificant difference in the variety and nitrogen rates wasfound in the combination of ex-sokoto and 50 kgNha

32 Effect of Nitrogen on the Growth Performance of Garlicduring the Period of the Experiment Plant height numberof leaves and leaf area differed significantly with differentnitrogen rates (Figures 6ndash8) 50 kgNha produced similarplant height and grew more leaves compared with thecontrol 0 kgNha which was significantly higher than 100and 150 kgNh The growth increases from 4WAS to 8WASafter which it declines Similarly nitrogen response differedsignificantly (119901 lt 005) in days to 50maturity (Figure 4(b))

With regard to the effect of nitrogen rates on the numberof bulbs fresh bulb and cured bulb yield responded signifi-cantly (Table 2) 50 kgNha recorded the maximum numberof bulbs and high bulb yield while 150 kgNha recorded thelowest


Table 1 Description of characters assessed during the study

Parameters assessed DescriptionPlant height Measured from the ground level to the tip of the tallest leaf with the aid of meter ruleNumber of leaves Recorded as the mean number of fully opened leaves from the 10 sampled plantsLeaf area Leaf area was measured and calculated using leaf parameter method as described in [25]Number of days to 50 maturity Number of plants with dried leaves in each plot was counted at maturity stageMatured bulb diameter Measured using vernier calliper from 10 air-cured bulbs with the mean expressed in centimeterIndividual bulb weight Ten air-cured bulbs sampled per plot were weighed on Mettler balanceNumber of cloves per bulb Cloves were separated from each of the 10 bulbs sampled per plot and counted

Cloves weight per bulb The weights of cloves separated per each of the 10 sampled bulbs were measured using Mettlerbalance

Fresh bulb yield Total weight of fresh bulb harvested from each net plot was recordedCured bulb yield Total bulbs harvested from each net plot were weighed after one week of air drying (curing)

Table 2 Effect of variety and nitrogen rates on the yield and yield components of garlic during the 20102011 dry season at Ajiwa

TreatmentMatured bulbdiameter(cm)

Individualbulb weight

(g)

Number ofcloves per

bulb

Cloves weightper bulb (g)

Number ofbulbs

Fresh bulbyield (kgha)

Cured bulbyield (kgha)

Varietyex-kofa 053b 141b 655b 125b 2042b 42250b 22417b

ex-sokoto 071a 177a 733a 164a 2975a 62500a 42917a

Mean 062 159 694 145 2509 52375 32667STDplusmn 013 025 055 028 660 14319 14496LSD (119901 lt 005) 012 032 070 032 526 18581 12649Nitrogen rates (kgha)0 062 162 670 148 2817a 61167a 36167a

50 073 188 733 170 3017a 66167a 41000a

100 057 150 703 140 2283a 50667a 29833a

150 055 135 670 120 1917b 31500b 23667b

Mean 062 159 694 145 2509 52375 32667STDplusmn 007 019 026 018 434 13287 6533LSD (119901 lt 005) mdash mdash mdash mdash 744 26277 14098Means with the same letter are not significantly different LSD least significant difference STD standard deviation


ex-kofaex-sokoto

R2= 09999Le

af ar

ea (c

m2)

0

5

10

15

20

25

Figure 3 Significant (119901 lt 005) growth trend of garlic varieties at 46 8 and 10 weeks after sowing on leaf area

33 Yield and Yield Components Response to Different Nitro-gen Rates and Garlic Varieties The result in Table 2 shows

the effect of variety and nitrogen rates on the maturedbulb diameter individual bulb weight number and weightof cloves per bulb number of bulbs and fresh and curedbulb weights The effect of variety was highly significant(119901 lt 005) in affecting all the yield and yield componentsof garlic during the period of the experiment The varietyex-sokoto appeared to be superior to ex-kofa throughout theexperiment (Table 2)

The significant effect of nitrogen rates showed that50 kgNha gave significantly higher number of bulbs andfresh and cured bulb weights than 150 kgNha which wassimilar with the control and 100 kgNhaNitrogen applicationincreases bulb yield initially at an increasing rate and thenincreases at a decreasing rate and then later at higher dosesignificantly decreases at a decreasing rate On the contrarymatured bulb diameter and individual bulb weight andnumber and weight of cloves per bulb showed no significanteffect (Table 2)


9175

885

ex-kofa ex-sokotoGarlic varieties

86

87

88

89

90

91

92

Day

s to

50

mat

urity

(a)

9317

9067

886788

0 50 100 150Nitrogen rates (kgNha)

85

86

87

88

89

90

91

92

93

94

Day

s to

50

mat

urity

(b)

Figure 4 Significant differences (119901 lt 005) between (a) variety least significant difference (LSD) 323 and (b) different nitrogen rates LSD457 in the days to 50 maturity of garlic

Nitrogen rates (kgha)

ex-kofaex-sokoto

Leaf

area

(cm

2)

150N100N50N0N05

10152025

Figure 5 Interaction effect of variety and nitrogen rates on the leafarea at 6WAS (LSD = 454)

150kgha100N

50N0N


15

20

25

30

35

Plan

t hei

ght (

cm)

Figure 6 Significant (119901 lt 005) growth trend of garlic response todifferent nitrogen rates at 4 6 8 and 10 weeks after sowing on plantheight during the period of the experiment

The effect of interaction between variety and nitrogenrates was found significant on the number of cloves per bulbof garlic during the period of the experiment (Figure 9) Thiswas apparent from the difference in the main effects (varietyand nitrogen) The result further depicts that 50 kgNha


150kgha100N

50N0N

2

4

6

8

Num

ber o

f lea

ves

Figure 7 Number of leavesrsquo response to different nitrogen ratesthroughout the period of the experiment

significantly gave the highest number of cloves per bulbcompared to the control 0 kgNha with ex-sokoto varietybeyondwhich there was no significant reductionThe ex-kofavariety produced similar number of cloves per bulb of garlicwith all the nitrogen rates

34 Correlation between Studied Characters To study therelationship between the yields and yield components corre-lation coefficient analysis was performed [27] This helps toestablish a better understanding of the relationship amongthe yield and yield related characters such as plant heightnumber of leaves leaf area number of bulbs and clovesweight Significant (119901 lt 005) and very strong-positivephenotypic relationships were observed among individualbulb weight cloves weight per bulb number of bulbs andfresh bulb and cured bulb yield characters (Table 3) Besidesmatured bulb diameter and individual bulb weight werefound to have a significant strong-positive association withplant height


Table 3 Coefficient of phenotypic correlations among the investigated garlic characters as response to different nitrogen rates

PH8 PH10 NLs8 NLs10 LA8 LA10 MBD IBW NCB CWB NB FBY CBYPH8 1PH10 0810 1NLs8 0881 0469 1NLs10 0420 0346 0165 1LA8 0897 0635 0765 0750 1LA10 0871 0866 0562 0738 0906 1MBD 0761 0978lowast 0368 0509 0669 0914 1IBW 0624 0936lowast 0184 0511 0554 0854 0982lowast 1NCB 0548 0613 0188 0946 0770 0876 0754 0763 1CWB 0524 0883 0060 0531 0485 0808 0949lowast 0991lowast 0776 1NB 0436 0880 minus0004 0240 0271 0648 0896 0946lowast 0540 0950lowastlowast 1FBY 0268 0768 minus0203 0312 0179 0577 0826 0914 0583 0947lowast 0973lowastlowast 1CBY 0474 0892 0021 0346 0351 0713 0926 0973lowast 0629 0979lowast 0994lowastlowast 0975lowastlowast 1lowastSignificant at 5 lowastlowastHighly significant at 1 PH8 plant height at 8WAS PH10 plant height at 10WAS NLs8 number of leaves at 8WAS NLs10 number ofleaves at 10WAS LA8 leaf area at 8WAS LA10 leaf area at 10WAS MBD matured bulb diameter IBW individual bulb weight NCB number of cloves perbulb CWB cloves weight per bulb NB number of bulbs FBY fresh bulb yield and CBY cured bulb yield


150kgha100N

50N0N

Leaf

area

(cm

2)

0

5

10

15

20

25

Figure 8 Significant (119901 lt 005) growth trend of garlic response todifferent nitrogen rates at 4 6 8 and 10 weeks after sowing on leafarea during the period of the experiment

4 Discussion

41 Garlic Varietal Response to Growth Characters Leaf is afood manufacturing factory for plants Leaf area is directlyrelated to photosynthesis as it provides more area for pho-tosynthetic activity which consequently affects the yield Thephotosynthetic material synthesized in the leaves primarilyflows down to the root zone for bulb formation Hence plantheight the number of leaves and leaf area are some of themost important measures of the plant vigour in garlic Leafnumber is directly related to variety characteristics [3] Thegarlic varieties tested were the available varieties cultivatedin the neighbouring areas of Ajiwa Katsina State They aremostly preferred by the consumer The variety ex-sokotoappeared to be more vigorous in terms of plant heightnumber of leaves and leaf area compared to the ex-kofathereby producing taller plants and it grew higher numberof leaves and wider leaves (leaf lamina) This work is inaccordance with the work [29] that reported significant leafnumber difference among garlic accessions and with the

0 50 100 150Nitrogen rates (KgNha)

ex-kofaex-sokoto

0

2

4

6

8

10N

umbe

r of c

love

s per

bul

b

Figure 9 Interaction effect of variety and nitrogen rates on thenumber of cloves per bulb (LSD = 168)

findings of [30] that reported significant difference in leafwidth and length in Iranian garlic In addition the varietyex-kofa took more days to mature compared to the ex-sokotovariety indicating that ex-sokoto variety matures earlier thanthe ex-kofa variety This is in harmony with the work [31] inwhich it was observed that Xian variety was earlier to matureand was harvested 18 days before the other tested varieties

42 Response of Nitrogen to the Growth Performance ofGarlic during the Period of the Experiment Plant heightwas apparently increased with increase in nitrogen up to50 kgNha beyond which there was significant reduction atthe later stage of growth (12WAS)The increase in plant heightdue to increase in nitrogen application indicates the positiverole of nitrogen in plant growth and that the soil was deficientin nitrogen for garlic requirementThis agrees with the worksof [16] that reported significant increase in plant heightwith the application of nitrogen fertilizer Particularly at theearly stage of growth the maximum number of leaves perplant was recorded with 50 kgNha which was significantly


Table 4 Physical and chemical properties of soil of the experimentalsite during 20102011

Soil characteristics Soil depth0ndash15 cm 15ndash30 cm

Chemical propertiespHw (1 1) 622 609pHc (1 2) 547 532Organic carbon () 074 036Total nitrogen () 097 058Available phosphorus () 736 644Exchangeable bases (meq100 g)Ca 253 262Mg 073 055K 021 019Na 028 024CEC 738 681Zn 036 039Cu 019 030Fe 713 847Mn 1309 1526Physical propertiesSand () 8168 8368Silt () 856 856Clay () 976 776Textural class Loam Loam

Table 5 Mean rainfall maximum and minimum temperature andrelative humidity at monthly interval during the period of theexperiment 20102011 dry season

Month Rainfall (mm)Temperature

(∘C) Relative humidity()

Max Min2010October 9258 3150 2075 mdashNovember mdash 3275 2150 mdashDecember mdash 3025 1775 mdash2011January mdash 2692 1605 mdashFebruary mdash 3152 1785 2224March mdash 3385 2010 3830Source Weather Station Katsina State Agricultural and Rural DevelopmentAuthority Katsina Nigeria

higher than the control This depicts that the increase innumber of leaves per plant as a result of an increase innitrogen indicates the positive role of nitrogen in increasingthe rates of leaf initiation and extension in early growth Thisfinding is in harmony with the study of [21] that reportedthat application of nitrogen significantly increased number ofleaves per plant Similarly further increment of nitrogen doseabove 50 kgNha has led to a reduction in the leaf area Thiscould be explained on the basis that nitrogen supply affectsgrowth and assimilation rates in plant mainly by altering the

size of the photosynthetic apparatus (leaf area) and it mayalso affect leaf efficiency [32] This is in agreement with [33]that reported that nitrogen application increased almost allgrowth parameters of garlic significantly

In essence plants grown with 50 kgNha produced themaximum vegetative growth which possibly enhanced themaximum photosynthetic activity and accumulation of drymatter in the plants The decrease in these traits as a resultof higher rates of nitrogen above 50 kgNha could be dueto imbalance of nutrients for excess application of nitrogenHowever with respect to days to 50 maturity the control(0 kgNha) had the highest number of days to 50 matu-rity compared to the other nitrogen rates and 150 kgNharecorded the lowest This shows that the more the increase innitrogen the fewer the number of days to 50 maturity andthe earlier thematurity Similar conclusionwas reported [34]This agrees with the statement of the fact that a high level ofnitrogen induces growth and forms a high level of proteins[19]

43 Response of Different Nitrogen Rates and Garlic Varietieson Yield Related Characters According to this investigationgarlic variety varies with respect to bulb diameter bulbweight number of cloves and cloves weight In harmonywith this study in [35] high variation was observed withrespect to bulb weight bulb diameter and yield in garlicThis might indicate that bulb weight should be considered inthe selection for garlic yield improving programsThe varietyex-sokoto which has protruded cloves and is not completelyround produced the highest number of bulbs and fresh andcured bulb yield compared to the ex-kofa variety that isglobular in shapeThis might be due to the fact that yield andquality varywith variety of garlic [35]The difference betweenthe tested varieties on bulb diameter number of cloves andcloves weight might be due to the fact that garlic genotypesby environmental conditions had a high contribution to clovenumber and are controlled by the interaction effect of anumber of genes This investigation agrees with [12] thatreported that among the tested varieties Clone 24 recordedthe highest total number of cloves It further reported thesignificant variation among the garlic varieties tested in bulbdiameter bulb weight and cloves weight

Availability of nitrogen is of prime importance for grow-ing plants as it is a major and indispensable source ofprotein and nucleic acid molecules It is also an integralpart of chlorophyll molecules which are responsible forphotosynthesis An adequate supply of nitrogen is associatedwith vigorous vegetative growth and more efficient useof available inputs finally leading to higher productivityProduction of maximum bulb yields by the application ofnitrogen at 50 kgNha could be due to production of tallerplants with higher number of leaves leading to increasedformation of vegetative structure for nutrient absorption andphotosynthesis and increased production of assimilates tofill the sink which result in increased bulb size and weightThe decrease in bulb yield at higher rates might be due toimbalance of nutrients for excess application of nitrogenThisinvestigation is in agreement with the findings of [11 30] that


observed significant increase in yield and yield componentsdue to nitrogen application The combination of ex-sokotovariety with nitrogen rate at 50 kgNha gave good vegetativegrowth and yield as when combined with the higher dosesof 100 and 150 kgNha during the experimental period at theexperimental site

44 Correlation between Characters Garlic bulb yield as inother crops is a quantitative character that is influenced bya number of yield contributing characters [36] Associationanalysis measures the mutual relationship between variouscharacters and it determines the component characters whichcould serve as selection criteria in crop improvement pro-gram The selection of desirable genotypes is usually basedon yield and yield components From this analysis it showsthat taller plants have better bulb diameter that leads to abetter bulb weight The higher the bulb weight the better theclove weight and size hence increasing the yield of garlic Inaddition number of bulbs has strong association with bulbyield

5 Conclusion

Fertilizers vary in type and composition and since the rangeof soil types on which they can be used is also wide firmrecommendations for their application to specific crops canonly be made if the local soil and climatic conditions areknown Based on the results obtained in this study it couldbe suggested that the use of ex-sokoto in combination with50 kgNha results in better garlic performance at AjiwaFurthermore for the improvement of garlic productionthrough selection matured bulb diameter individual bulbweight number of bulbs and cloves weight per bulb couldbe suggested as revealed from this investigation

However the parameters discussed above are function ofenvironmental variability so estimates may differ in otherenvironments but at Ajiwa and areas with similar soil andclimate conditions this could be useful Further researchescould be carried out at various agroclimate and soil type toidentify suitable varieties for maximum productivity

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors sincerely acknowledged Saleh Salleh who helpedrun the analysis

References

[1] J W Purseglove Tropical Crops Monocotyledons LongmanLondon UK 1972

[2] ldquoReport on horticultural crops research programmerdquo in Pro-ceedings of the 1996 Cropping Scheme Meeting Institute forAgricultural Research Ahmadu Bello University Zaria Nigeria1996

[3] TG TadeseParticipatory varietal evaluation and farmers-basedseed production A sustainable approach to garlic seed delivery inAtsbi Womberta Woreda Eastern Tigray [MS thesis] Depart-ment of Crop and Horticultural Science Mekelle UniversityMekrsquoele Ethiopia 2009

[4] K Tyler D May J Guerard D Ririe and J Hatakeda ldquoDiag-nosing nutrient needs of garlicrdquo California Agriculture vol 42no 2 pp 28ndash29 1988

[5] National Horticultural Research and Development Foundation(NHRDF) 2008 httpnhrdfcom

[6] FAOmdashFood and Agricultural Organization Rome The Originand Distribution of Garlic USDA Agricultural Research UnitWashington DC USA 2001

[7] B B D Inuwa ldquoA study of issues arising from the productionof garlic (Allium sativum L) in Nigeriardquo in Proceedings ofthe Training Workshop on Improving and Accelerated GarlicProduction for Local and Export Needs in Nigeria at FoodCrops Production Technology Transfer Station (FDA) p 16 DanHassan Kano Nigeria 2001

[8] Gvodenovic-Varga and M Vasic ldquoResponse of Spring GarlicEcotypes to environmental Growth conditionsrdquo Natura Mon-tenegrina Podgorica vol 8 no 2 pp 73ndash81 2008

[9] B Roger C Jay R Becker et al Growing Garlic in MinnesotaUniversity of Minnesota Extension 2008

[10] A A Midan M M El-Sayed R M Khalil and M A FathallaldquoGrowth and assimilation performance in garlic in relation togrown cultivar and nitrogen fertilizationrdquo Emirates Journal ofFood and Agriculture vol 4 no 1 pp 27ndash51 1992

[11] J L Brewester Onions and Other Vegetable Alliums CropProduction Science in Horticulture Horticulture ResearchInternational Wellesbourne UK 2008

[12] A Z OsmanMNMHassan andA AM El-Hamied ldquoEffectof NPK fertilizer application dates on growth yield and qualityof two garlic cultivarsrdquo Minia Journal of Agricultural ResearchDevelopment vol 13 no 2 pp 577ndash596 1991

[13] S H Aly Growth and yield of some garlic ecotype as affected bydifferent cultural practices under assiut conditions [PhD thesis]Faculty of Agriculture Assiut University 2010

[14] S-N H Gadel-Hak Y MMMoustafa G F Abdel-Naem andI A Abdel-Wahab ldquoStudying different quantitative and quali-tative traits of some white- and colored-bulb garlic genotypesgrown under a drip irrigation systemrdquo Australian Journal ofBasic and Applied Sciences vol 5 no 6 pp 1415ndash1427 2011

[15] S Brahman and M N Yousuf Effect of Nitrogen and Potassiumon the Growth and Yield of Garlic Research Report for 2008Spice Research Centre Bari Bangladesh 2008

[16] I SNaruka andR SDhaka ldquoEffect of row spacing andnitrogenfertilization on growth yield and composition of bulb in garlic(Allium sativum L) cultivarsrdquo Journal of Spices and AromaticCrops vol 10 no 2 pp 111ndash117 2001

[17] H B Singh The Role of Manures and Fertilizers in CropProduction Developing Agric-Input Markets in Nigeria IFDE2002

[18] F Romojaro M C Martinez Madrid and M T PretzelldquoPreharvest factors determining the quality and conservationpostharvest agricultural productsrdquo 2007 (Spanish) httpwwwhorticomcompdimagenes6590665906pdf

[19] A P Rodaz and Y P Rizobacter ldquoTratamiento para inducercolor en citicosrdquo 2005

[20] J G Buwalda ldquoNitrogen nutrition of garlic (Allium sativumL) under irrigation Components of yield and indices of crop


nitrogen statusrdquo Scientia Horticulturae vol 29 no 1-2 pp 69ndash76 1986

[21] A A Kakar M K Abdullahzai M Salim and S A Qaim ShahldquoEffect of nitrogenous fertilizer on growth and yield of garlicAgricultural Research Institute Sariab Quetta PakistanrdquoAsianJournal of Plant Science vol 1 no 5 pp 544ndash545 2002

[22] M A Farooqui I S Naruka P P Singh S S Rathore and R PS Shaktawat ldquoEffect of Nitrogen and sulphur levels on growthand yield of garlic (Allium sativum L)rdquo Asian Journal of Foodand Agro-Industry vol 2 pp 18ndash23 2008

[23] B A Babaji Effect of plant spacing and nitrogen fertilizationon growth and yield of garlic [MS thesis] ABU Zaria ZariaNigeria 1994

[24] A M Bichi Response of garlic (Allium sativum L) to varyinglevels of phosphorus and nitrogen [BSc thesis] Department ofAgronomy ABU Zaria Nigeria 1997

[25] M Djordge B Vukasin S Dubravka et al ldquoEffect of plantdensity on the characteristics of photosynthetic apparatus ofthe garlic (Allium sativum var vulgare L)rdquo African Journal ofBiotecnology vol 10 no 71 pp 15861ndash15868 2011

[26] J M Kowal and D T Knabe An Agroclimatological Atlas ofthe Northern States of Nigeria Ahmadu Bello University ZariaNigeria 1972

[27] SAS SAS Institute Inc SAS Campus Drive Cary NC USA2003

[28] P Kashiani and G Saleh ldquoEstimation of genetic correlationson sweet corn inbred lines using SAS mixed modelrdquo AmericanJournal of AgriculturalampBiological Science vol 5 no 3 pp 309ndash314 2010

[29] T Kassahun Variability and association among bulb yield andyield related traits in garlic [MS thesis] Alemaya UniversityDire Dawa Ethiopia 2006

[30] K Baghalian M R Naghavi S A Ziai and H N Badi ldquoPost-planting evaluation of morphological characters and allicincontent in Iranian garlic (Allium sativum L) ecotypesrdquo ScientiaHorticulturae vol 107 no 4 pp 405ndash410 2006

[31] A C Hatfield-Nicholson Juniata High Tunnel Garlic VarietyStudymdashPlasticulture Penn State Extension College of Agricul-tural Sciences 2010

[32] R E McCollum ldquoAnalysis of potato growth under differentP regimes time by P-status interactions for growth and leafefficiencyrdquo Agronomy Journal vol 70 pp 58ndash66 1978

[33] M Usman Influence of different levels of nitrogen fertilizer onthe growth and yield of garlic (Allium sativum L) varietiesunder irrigation at Ajiwa Katsina State Nigeria [Bsc thesis]Department of Crop Science Faculty of Agriculture ATBUBauchi Nigeria 2012

[34] D R Panthee P P Subedi S Bhattarai and J Dhakal ldquoDiversityanalysis of garlic germplasm available in Nepal based morpho-logical charactersrdquo Genetic Resource Crop Evaluation Journalvol 53 no 1 pp 205ndash212 2004

[35] J Bachmann and T Hinman ldquoGarlic Organic ProductionrdquoNational Center for Appropriate Technology une publicationdrsquoATTRA Etats-Unis[En ligne] 2008 httpsattrancatorg

[36] A G Addissu ldquoHeritability and genetic advance in recom-binant inbred lines for drought tolerance and other relatedtraits in sorghum (sorghum bicolor)rdquo Continental Journal ofAgricultural Science vol 5 pp 1ndash9 2012

Submit your manuscripts athttpwwwhindawicom

Nutrition and Metabolism

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014


Food ScienceInternational Journal of

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The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

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Applied ampEnvironmentalSoil Science

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AgricultureAdvances in


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characteristics such as the relative growth rate plant heightnumber of leaves leaf area and net assimilate rate [10ndash13]due to grown cultivars Recently [14] reported variations inplant vigour among six garlic genotypes tested with Egaseed1 and Sid 40 recorded the highest plant vigour comparedto the other varieties Earlier reports [3] showed that therewas significant difference in plant height among the testedvarieties Variety Tsedey 92 recorded the highest plant heightcompared to the local variety Rie at Tegahne irrigation siteGolgol Naele and Atsbi Womberta Wereda It was reportedin [15] that there was significant difference among 17 cultivarsof garlic in plant height in 1995 rainy and 1996 dry seasons(under irrigation) at Debre Zeit

Chemical fertilizers have becomewidely used in vegetableproduction in tropical areas particularly where they arereadily available It is well known that the use of fertilizerhelps in production and is somewhat a quick method forachieving maximum yield [16] Nitrogen is generally founddeficient in most of the African soils particularly in theareas where farmers practice intensive cultivation and growhigh yielding varieties [17] Availability of nitrogen is ofprime importance for growing plants as it is an integralpart of chlorophyll molecules which are responsible forphotosynthesis [18] A high rate of nitrogen induces growthforms high amount of proteins and by competence reducesanthocyanin synthesis because a high amount of aminoacids is destined to form proteins [19] Nitrogen is amongthe most important nutrient elements in garlic and othercrops and actively acts in numerous metabolic processesNitrogen supply was reported [20] to affect growth andassimilation rates in plant mainly by altering the size ofthe photosynthetic apparatus (leaf area) and it may alsoaffect leaf efficiency Nitrogen fertilizer increased the rate ofleaf appearance and the rate of leaf extension particularlyfor the first leaf following effects on tissue nitrogen Bulbgrowth also responded significantly to applied nitrogen [20]Increasing nitrogen rates to 100 kgNha resulted in longerleaves and greater number of leaves per plant [21] In anothertrial [2] the growth and yield parameters increased withincreasing nitrogen rates up to 150 kgNha However higherrates of nitrogen beyond 150 kg decreased growth and yield200 kgNha significantly increases the yield parameters likeneck thickness bulb diameter number of cloves per bulband fresh weight of 20 cloves [22] However at Samaru inNigeria [23] nitrogen application increased almost all growthand yield parameters of garlic significantly and themaximumyield of 15 tha was recorded with 90 kgNha Furthermore[24] recorded significant increase in bulb yield with theapplication of 75 kgNha while clove weight increased only at150 kgNha beyond which there was a significant reduction

The wide gap between present low yield and the poten-tial yield of garlic in Nigeria is an indication of severalconstraints that are limiting garlic production Some ofthese limiting factors are environmental While other fac-tors are due to agronomic or cultural practices Some ofthe major constraints include inadequate fertilizer weedschemicals storage and transportation facilities Howeverthe per-hectare yield of garlic can be increased by adoptingproper package of practices like timely planting proper

spacing and judicious application of irrigation water andbesides these balance application of nitrogen plays a vitalrole in the development of garlic [21] There is dearth ofinformation on garlic production in Nigeria except for someworks done at Samaru on spacing fertilizer and irrigationrequirements [24] Generally it is in view of this backgroundthat this study was undertaken with the aim of exploringopportunities to improve the productivity of garlic throughthe choice of appropriate levels of nitrogenous fertilizer andsuitable cultivar which maximizes yield The objectives wereto determine the influence of nitrogenous fertilizer on theperformance of two garlic varieties and their interactionsThe hypothesis for this work was as follows H

0there is no

significant variation between the two garlic varieties withrespect to their growth and yield performance and differentnitrogen fertilization does not affect the growth and yield ofgarlic

2 Materials and Methods

21 Site and Location Field experimentwas conducted underirrigation during 20102011 dry season at the Katsina StateIrrigation Site Ajiwa The site is approximately located at13∘011015840N and 7∘411015840E and 619m above sea level in the Sudansavannah ecological zone of Nigeria [26] The soil of theexperimental site was loamy soil A detail of the physio-chemical analysis of the soil was presented in Table 4 whilemeteorological data was presented in Table 5

22 Treatments and Experimental Design The treatmentsconsisted of factorial combination of two garlic varieties (ex-kofa and ex-sokoto) and four nitrogen rates (0 50 100 and150 kgNha) These were arranged in a randomized completeblock design and replicated three times The total area forthe experiment was 16m times 65m The field was furthermade into three replicates with 10m spacing between thereplicates Each replicate comprises 8 plots (each representinga treatment combination) with 05m spacing between theplots The experimental field was cleared ploughed andharrowed to pulverize the soil before making a plot of 15mtimes 15m as gross size in sunken appearance The gross plotsize was 225m2 and the net plot size was 1m2 The net plotwas ldquothe central area where observations were takenrdquo Thisis to avoid bias due to interference between plots The plotswere bounded by low bounds in order to retain the irrigationwaterTheuniforms inter- and intrarow spacing of 10 cmwereused Each gross size plot consists of 15 rows with 15 holes perrow and a total of 225 plants per plot and 100 per net plot(10 rows with 10 holes per row) The total plant populationwas 5400 plants during the experimental period The cropreceived an application of nitrogen fertilizer as urea (46)according to the treatments in two equal split doses A basaldose of half the nitrogen rate was applied and incorporated atsowing The second dose of the nitrogen was applied at fourweeks after sowing (4WAS) The fertilizer was incorporatedmanually using hand hoe

23 Experimental Material Local variety of garlic ex-kofais popularly grown around Kofa village in Kano State






3 Results


ex-kofaex-sokoto

R2= 09974


05

10152025303540

Plan

t hei

ght (

cm)


ex-kofaex-sokoto


0

2

4

6

8

Num

ber o

f lea

ves

R2= 09373













(g)

Number ofcloves per

bulb


Number ofbulbs






50 073 188 733 170 3017a 66167a 41000a

100 057 150 703 140 2283a 50667a 29833a

150 055 135 670 120 1917b 31500b 23667b



ex-kofaex-sokoto

R2= 09999Le

af ar

ea (c

m2)

0

5

10

15

20

25






9175

885


86

87

88

89

90

91

92

Day

s to

50

mat

urity

(a)

9317

9067

886788


85

86

87

88

89

90

91

92

93

94

Day

s to

50

mat

urity

(b)



ex-kofaex-sokoto

Leaf

area

(cm

2)

150N100N50N0N05

10152025


150kgha100N

50N0N


15

20

25

30

35

Plan

t hei

ght (

cm)




150kgha100N

50N0N

2

4

6

8

Num

ber o

f lea

ves








150kgha100N

50N0N

Leaf

area

(cm

2)

0

5

10

15

20

25


4 Discussion



ex-kofaex-sokoto

0

2

4

6

8

10N

umbe

r of c

love

s per

bul

b




















5 Conclusion



Competing Interests


Acknowledgments


References









































Journal of




Agronomy





Microbiology




Volume 2014





























3 Results


ex-kofaex-sokoto

R2= 09974


05

10152025303540

Plan

t hei

ght (

cm)


ex-kofaex-sokoto


0

2

4

6

8

Num

ber o

f lea

ves

R2= 09373













(g)

Number ofcloves per

bulb


Number ofbulbs






50 073 188 733 170 3017a 66167a 41000a

100 057 150 703 140 2283a 50667a 29833a

150 055 135 670 120 1917b 31500b 23667b



ex-kofaex-sokoto

R2= 09999Le

af ar

ea (c

m2)

0

5

10

15

20

25






9175

885


86

87

88

89

90

91

92

Day

s to

50

mat

urity

(a)

9317

9067

886788


85

86

87

88

89

90

91

92

93

94

Day

s to

50

mat

urity

(b)



ex-kofaex-sokoto

Leaf

area

(cm

2)

150N100N50N0N05

10152025


150kgha100N

50N0N


15

20

25

30

35

Plan

t hei

ght (

cm)




150kgha100N

50N0N

2

4

6

8

Num

ber o

f lea

ves








150kgha100N

50N0N

Leaf

area

(cm

2)

0

5

10

15

20

25


4 Discussion



ex-kofaex-sokoto

0

2

4

6

8

10N

umbe

r of c

love

s per

bul

b




















5 Conclusion



Competing Interests


Acknowledgments


References









































Journal of




Agronomy





Microbiology




Volume 2014
































(g)

Number ofcloves per

bulb


Number ofbulbs






50 073 188 733 170 3017a 66167a 41000a

100 057 150 703 140 2283a 50667a 29833a

150 055 135 670 120 1917b 31500b 23667b



ex-kofaex-sokoto

R2= 09999Le

af ar

ea (c

m2)

0

5

10

15

20

25






9175

885


86

87

88

89

90

91

92

Day

s to

50

mat

urity

(a)

9317

9067

886788


85

86

87

88

89

90

91

92

93

94

Day

s to

50

mat

urity

(b)



ex-kofaex-sokoto

Leaf

area

(cm

2)

150N100N50N0N05

10152025


150kgha100N

50N0N


15

20

25

30

35

Plan

t hei

ght (

cm)




150kgha100N

50N0N

2

4

6

8

Num

ber o

f lea

ves








150kgha100N

50N0N

Leaf

area

(cm

2)

0

5

10

15

20

25


4 Discussion



ex-kofaex-sokoto

0

2

4

6

8

10N

umbe

r of c

love

s per

bul

b




















5 Conclusion



Competing Interests


Acknowledgments


References









































Journal of




Agronomy





Microbiology




Volume 2014

























9175

885


86

87

88

89

90

91

92

Day

s to

50

mat

urity

(a)

9317

9067

886788


85

86

87

88

89

90

91

92

93

94

Day

s to

50

mat

urity

(b)



ex-kofaex-sokoto

Leaf

area

(cm

2)

150N100N50N0N05

10152025


150kgha100N

50N0N


15

20

25

30

35

Plan

t hei

ght (

cm)




150kgha100N

50N0N

2

4

6

8

Num

ber o

f lea

ves








150kgha100N

50N0N

Leaf

area

(cm

2)

0

5

10

15

20

25


4 Discussion



ex-kofaex-sokoto

0

2

4

6

8

10N

umbe

r of c

love

s per

bul

b




















5 Conclusion



Competing Interests


Acknowledgments


References









































Journal of




Agronomy





Microbiology




Volume 2014




























150kgha100N

50N0N

Leaf

area

(cm

2)

0

5

10

15

20

25


4 Discussion



ex-kofaex-sokoto

0

2

4

6

8

10N

umbe

r of c

love

s per

bul

b




















5 Conclusion



Competing Interests


Acknowledgments


References









































Journal of




Agronomy





Microbiology




Volume 2014








































5 Conclusion



Competing Interests


Acknowledgments


References









































Journal of




Agronomy





Microbiology




Volume 2014












































Journal of




Agronomy





Microbiology




Volume 2014
























research article phenotypic response of two garlic varieties...

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