Response of tomato cultivars differing in growth habit to nitrogen and phosphorus fertilizers and spacing on vertisol in Ethiopia

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1 Act griculture Slovenic, 91-1, mj 2008 str DOI: /v Agrovoc descriptors: tomtoes, lycopersicon esculentum, vrieties, crop yield, crop performnce, spcing, fertilizer ppliction, phosphorus, phosphte fertilizers, nitrogen, nitrogen fertilizers, Ethiopi Agris ctegory codes: F04, F61, F62 COBISS Code 1.01 Response of tomto cultivrs differing in growth hit to nitrogen nd phosphorus fertilizers nd spcing on vertisol in Ethiopi Tesfye BALEMI 1 Received: June 29, 2007; ccepted: Mrch 21, Prispelo 29. junij 2007; sprejeto 21. mrc ABSTRACT A field experiment ws conducted on vertisol t Amo University College (Ethiopi) during 2003/2004 nd 2004/2005 cropping sesons to investigte the response of tomto cultivrs vrying in growth hit to rtes of Nitrogen (N) nd Phosphorus (P) fertilizers nd plnt spcing. The tretment consisted of fctoril comintion of two cultivrs (Mrgeloe nd Melk shol), three NP fertilizers rtes (50 kg N + 60 kg P 2 O 5 /h, 80 kg N + 90 kg P 2 O 5 /h nd 110 kg N kg P 2 O 5 /h) nd three spcing (100 cm x 30 cm, 80 cm x 30 cm nd 60 cm x 45 cm) rrnged in Rndomized Complete Block Design. Results reveled tht fertilizer rtes nd spcing significntly ffected the totl nd mrketle fruit yields s well s % mrketle fruit yield. Similrly, plnt vigor (plnt height), numer of fruits per cluster nd 10 fruit weight were significntly influenced y ll of the min fctors. Besides the min fctors effect, fertilizer rte*spcing nd cultivr*spcing interction effects were lso oserved on % mrketle fruit yield nd 10 fruit weight, respectively. The results of 2003/2004 cropping seson showed tht the ppliction of 110 kg N kg P 2 O 5 /h or 80 kg N + 90 kg P 2 O 5 /h resulted in significntly higher totl s well s mrketle fruit yield of the tomto cultivrs. Result of 2004/2005 cropping seson, however, demonstrted tht only the ppliction the highest fertilizer rte (110 kg N kg P 2 O 5 /h ) resulted in superior fruit yields whilst the other two rtes did not significntly differ from ech other in ffecting fruit yields. Results of oth cropping sesons confirmed significntly higher % mrketle fruit yield due to the ppliction of either 110 kg N kg P 2 O 5 /h or 80 kg N + 90 kg P 2 O 5 /h. Closer spcing of 80 cm x 30 cm nd 60 cm x 45 cm gve higher totl s well s mrketle fruit yield thn the wider spcing of 100 cm x 30 cm. Key words: fertilizer rte, mrketle fruit yield, tomto cultivrs, totl fruit yield, spcing 1 Deprtment of Plnt Sciences, Amo University College, P.O Box 19, Ethiopi, E-mil: tesfye2005@yhoo.co.uk

2 104 Act griculture Slovenic, 91-1, mj 2008 IZVLEČEK VPLIV GNOJENJA Z DUŠIKOM IN FOSFORJEM NA RASTLINE KULTIVARJEV PARADIŽNIKA Z RAZLIČNO RASTJO NA VERTISOLU V ETIOPIJI N Amo University College v Etiopiji je il v letih 2003/2004 in 2004/2005 izveden poljski poskus z dvem kultivrjem prdižnik (determinntnim in nedeterminntnim) d i rziskli vpliv gnojenj z dušikom (N) in fosforjem (P) ter rzdlje med rstlinmi n prdižnik. Izveden je il fktorski poskus z dvem kultivrjem (Mrgeloe in Melk shol), tremi odmerki gnojil NP (50 kg N + 60 kg P 2 O 5 /h, 80 kg N + 90 kg P 2 O 5 /h in 110 kg N kg P 2 O 5 /h) in tremi rzdljmi med rstlinmi (100 cm x 30 cm, 80 cm x 30 cm in 60 cm x 45 cm) v nključnem loku. Rezultti so pokzli, d so stopnje gnojenj in gostot rstlin znčilno vplivli n celoten in tržen pridelek rslin, kot tudi n odstotek uporneg pridelk. Podono so ile višine rstlin, tež in število plodov v znčilni povezvi z vsemi glvnimi fktorji. Poleg glvnih vplivom so vplivle tudi interkcije gnojenje*gostot in kultivr*rzdlje tko n % tržneg pridelk plodov kot n težo 10 plodov. Rezultti v sezoni 2003/2004 so pokzli d je upor 110 kg N kg P 2 O 5 /h li 80 kg N + 90 kg P 2 O 5 /h omogočil znčilno višje celokupne in tržne pridelke prdižnikov pri oeh kultivrjih. Tod v sezoni 2004/2005 je smo njvišji odmerek gnojil (110 kg N kg P 2 O 5 /h ) dl višje pridelke. Rezultti oeh sezon skupj so potrdili višji % tržneg pridelk pri upori 110 kg N kg P 2 O 5 /h li 80 kg N + 90 kg P 2 O 5 /h. Gostejš sditev (80 cm x 30 cm ozirom 60 cm x 45 cm) je dl višje pridelke kot redkejš sditev (100 cm x 30 cm). Ključne esede: celoten pridelek, gostot sditve, kultivrji prdižnik, odmerki gnojil, tržni pridelek INTRODUCTION Tomto (Lycopersicon esculentum L.) is the most widely grown vegetle in the world eing recognized s rech source of vitmins nd minerls. It is lso mong the most importnt vegetle crops in Ethiopi. The totl production of this crop in the country hs shown mrked increse (Lemm et l., 1992) since it ecme the most profitle crop providing higher income to smll scle frmers compred to other vegetle crops. However, tomto production is highly constrined y severl fctors especilly in developing ntions like Ethiopi. The ntionl verge of tomto fruit yield in Ethiopi is often low (125 q/h) compred even to the neighoring Africn countries like Keny (164 q/h) (FAO Production Yer Book, 2004). Current productivity under frmers condition is 90 q/h, wheres yield up to 400 q/h cn e recorded on reserch plots (personl communiction). In Ethiopi, frmers get lower yield minly due to diseses nd pests s well s due to su-optiml fertiliztion. Mehl et l., (2000) nd Pndey et l., (1996) reported tht fruit yield in tomto is highly influenced y the NP fertilizers rtes pplied. Similrly, Sherm et l., (1999) lso reported verge fruit weight of tomto to hve een influenced y the mount of NP fertilizers rtes pplied. Thus, tomto plnt should receive optimum mount of NP fertilizers to produce higher fruit yields. According to ( 2007) the totl nitrogen (kg h -1 ) required to chieve trget fruit yield is estimted y multiplying the trget yield in tons per hectre y 2.4. Similrly, P 2 O 5 requirement per hectre cn e estimted y multiplying N requirement y 0.35 ( 2007).

3 BALEMI, T.: Response of tomto cultivrs differing in growth hit to nitrogen 105 Improper plnt spcing is lso mong the notle resons of low productivity of this crop. Lemm et l., (1992) reported tht plnt spcing gretly influenced fruit yield in oth fresh mrket nd processing tomtoes. Likewise, Godfrey-Sm-Aggrey et l., (1985) nd Mehl et l., (2000) lso reported yield prmeters in tomto to hve een ffected y spcing. In Ethiopi, so fr plnt spcing nd fertilizer rtes were determined for tomtoes only t Melks reserch center which cn not gro-ecologiclly represent the other tomto growing regions of the country nd especilly no such study ws done in tomtoes under vertisol condition nd the whole of such previous gronomic studies were confined only to sndy lom soils of the rift vlley regions of the country. Although the tomto growers in the rift vlley regions cn directly use the recommendtion from this reserch center, the sme recommendtion however, cn not pply for the other tomto growing regions with completely different groecology. In tropics in generl, the common fertilizer ppliction rtes ccording to literture re kg N, nd kg P 2 O 5 nd kg K 2 O per hectre ( 2007). However, this would lso e too generl to use for specific regions. Since spcing requirement of tomto depends on soil type nd its inherent fertility (Lemm et l., 1992) nd the type of cultivrs (Mehl et l., 2000), the use of lnket recommendtion would e inpproprite nd it would e indispensle to identify pproprite recommendtion for specific soil types nd cultivrs grown in the region. Thus, the present investigtion ws proposed with n ojective to determine n optimum fertilizer rte nd plnt spcing for tomto cultivrs with contrsting growth hits grown in vertisol dominted region of the centrl Ethiopi. MATERIALS AND METHODS The experiment ws conducted in the field for two yers (2003/2004 nd 2004/2005 cropping sesons) on vertisol in Ethiopi t Amo University College experimentl sttion during offseson with irrigtion. Two commonly grown tomto cultivrs with contrsting growth hit (Mrgeloe: n indeterminte cultivr nd Melk shol determinte type) were used for the study. The tretments consisted of fctoril comintion of two ove mentioned cultivrs, three spcings (100 cm x 30 cm, 80 cm x 30 cm nd 60 cm x 45 cm) where the lrger spcing lwys stnds for inter-row spcing nd the other for intr-row spcing) nd three fertilizer rtes (50 kg N/h + 60 kg P 2 O 5 / h, 80 kg N/h + 90 kg P 2 O 5 / h nd 110 kg N/h kg P 2 O 5 / h). A totl of 18 tretments were lid out in Rndomized Complete Block Design (RCBD) with three replictions. The plot size used ws 1.8 m x 4 m (Plot re = 7.2 m 2 ) in oth yers of experimenttion. The nitrogen fertilizer (N) ws pplied s ure wheres phosphorus (P) ws pplied in the form of Dimmonium Phosphte (DAP) oth of which re commonly used forms of chemicl fertilizers y the smll-scle frmers nd commercil growers in the country. The whole mount of phosphte fertilizer ws pplied t trnsplnting wheres nitrogen ws given t two equl splits (hlf t trnsplnting nd the rest hlf 30 dys fter trnsplnting) s sl ppliction. No ny other nutrient ws pplied since especilly Potssium is not limiting in most Ethiopin soils. Dt ws recorded on plnt height (plnt vigor) t 60 dys fter trnsplnting, numer of fruits per cluster nd 10 fruit weight only during the first cropping seson experiment. However, dt on totl nd mrketle fruit yields were recorded during oth cropping seson experiments. Dt for plnt height nd numer of fruits per cluster were determined for 5 rndomly selected smple plnts for every tretment in ech lock (i.e. vlues of ech tretment in every lock re verges of 5 plnts). To see the effect of ech fctor (cultivrs, spcing nd fertilizer rte) on the mesured prmeters, the dt were nlyzed y nlysis of vrince-anova nd in ll cses mens were compred t = 0.05 proility level ccording to Tukey test using SAS sttisticl softwre.

4 106 Act griculture Slovenic, 91-1, mj 2008 RESULTS AND DISCUSSION 1. Effect of min fctors on totl fruit yield Fertilizer rte Generlly, higher totl fruit yield ws otined during the first yer (2003/2004 cropping seson) experiment thn during the second yer (2004/2005 cropping seson) experiment. This ws minly ecuse the fruits were hrvested over n extended period of time during the first yer experiment. The nlysis of vrince (ANOVA) showed tht there ws significnt min effect of fertilizer rtes (P<0.01) on the totl fruit yield of the tomto cultivrs during oth cropping sesons (Tles 1 nd 2). During the first yer experiment, significntly higher totl fruit yield (80.5 kg plot -1 ) ws otined with the ppliction of 110 kg N kg P 2 O 5 per hectre s compred to the ppliction of 50 kg N + 60 kg P 2 O 5 per hectre which gve totl fruit yield of only 66 kg plot -1 (Figure 1). During the sme yer, the ppliction of 80 kg N + 90 kg P 2 O 5 per hectre resulted in totl fruit yield of 73 kg plot -1 which ws on pr with tht otined with the ppliction of the highest fertilizer rte (110 kg N kg P 2 O 5 per hectre). During the second yer experiment (2004/2005 cropping seson), significntly higher totl fruit yield (46.6 kg plot -1 ) ws otined with the ppliction of 110 kg N kg P 2 O 5 per hectre s compred to the ppliction of oth 80 kg N + 90 kg P 2 O 5 nd 50 kg N + 60 kg P 2 O 5 per hectre which gve totl fruit yield of 38.3 nd 35.7 kg plot -1, respectively (Figure 1). The ppliction of 80 kg N + 90 kg P 2 O 5 per hectre did not significntly differ from the ppliction of 50 kg N + 60 kg P 2 O 5 per hectre in ffecting the totl fruit yields of the tomto cultivrs during oth cropping sesons. Higher totl fruit yield in tomto t higher NP rte ws reported y Rshid (1993), Pndey et l., (1996) nd Mehl et l., (2000), which is in greement with the present finding. Spcing Totl fruit yield ws lso significntly ffected y the spcing (P< 0.05) during oth yers experiments (Tles 1 nd 2). During the first yer experiment, the men totl fruit yield of the tomto cultivrs rnged etween 78.6 kg plot -1 nd 67.6 kg plot -1 due to spcing effect which ws significntly different (P< 0.05)(Figure 4). A plnt spcing of 80 cm x 30 cm resulted in the highest men totl fruit yield (78.6 kg plot - 1 ) wheres spcing of 100 cm x 30 cm gve the lowest men totl fruit yield (67.6 kg plot -1 ). Likewise, similr effect of spcing on the totl fruit yield ws oserved during the second yer experiment. A closer spcing of 80 cm x 30 cm resulted in significntly higher totl fruit yield (44.0 kg plot -1 ) s compred to wider spcing of 100 cm x 30 cm which gve totl fruit yield of kg plot -1. However, spcing of 60 cm x 45 cm gve totl yield which ws on pr with the other spcing tretments during oth cropping sesons. The present finding drws support from erlier reports of Reeve nd Schmidth (1952), Zhr (1970), Gupt nd Shukl (1977), Ali (1995), Teerpolvichitr (1983), Hmid (1985), Nssr (1986) nd Mohmed nd Ali (1986) who similrly reported the highest totl fruit yield of tomto t closer spcing thn t wider spcing. The highest totl fruit yield of the tomto cultivrs t closer spcing could e due to the higher plnt popultion per

5 BALEMI, T.: Response of tomto cultivrs differing in growth hit to nitrogen 107 plot t closer spcing thn t wider spcing s reported y Ji (1992). Moreover, the closer spcing might hve enled mximized use of the pplied nutrients etter thn the wider spcing s hs een suggested y Ming (1983). Cultivrs Cultivrs did not significntly differ in totl fruit yield during oth yer experiments (Tles 1 nd 2). Interction effects No interction effects of ll fctors on totl fruit yield were oserved during oth yer experiments in the present finding (Tles 1 nd 2). However, Mehl et l. (2000) reported significnt interction effects of cultivr*spcing nd fertilizer*spcing for totl fruit yield in tomto. 2. Effect of min fctors on mrketle nd % mrketle fruit yield Fertilizer rte Mrketility of the produce is of prmount importnce to tomto growers since they primrily produce for mrket. In the present study, undersized fruits, sunscld fruits nd fruits ttcked y insects were regrded s unmrketle fruits. Mrketle nd % mrketle fruit yield were significntly ffected y fertilizer rtes (P<0.001) during oth cropping sesons (Tles 1 nd 2). During oth yer experiments, the trend of fertilizer effect on totl fruit yield ws lso similr to its effect on mrketle fruit yield. During the first yer experiment (2003/2004 cropping seson), ppliction of the highest fertilizer rte (110 kg N kg P 2 O 5 /h) gve significntly higher men mrketle fruit yield (76.1 kg plot -1 ) thn the lowest fertilizer rte (50 kg N + 60 kg P 2 O 5 /h) which gve men mrketle fruit yield of only 59.1 kg plot -1 (Figure 2). During 2004/2005 cropping seson, the sme fertilizer rte (110 kg N kg P 2 O 5 /h) exerted significnt influence in oosting mrketle fruit yield s compred to the other rtes. The ppliction of 110 kg N kg P 2 O 5 per hectre resulted in men mrketle fruit yield of 41.4 kg plot -1 which ws significntly higher s compred to mrketle fruit yield of 33.0 kg plot -1 nd 27.2 kg plot -1, which were otined with the ppliction of 80 kg N + 90 kg P 2 O 5 nd 50 kg N + 60 kg P 2 O 5 per hectre, respectively. Appliction of 80 kg N + 90 kg P 2 O 5 nd 110 kg N kg P 2 O 5 per hectre resulted in men mrketle fruit yields which were on pr during the first yer ut significntly different during the second yer experiment. For ll levels of fertilizer, % mrketle fruit yield of the tomto cultivrs significntly differed during 2003/2004 cropping seson (Figure 3). Appliction of 110 kg N kg P 2 O 5 per hectre resulted in significntly higher men % mrketle fruit yield (94 %) thn the other two levels, 80 kg N + 90 kg P 2 O 5 nd 50 kg N + 60 kg P 2 O 5 per hectre, which gve men % mrketle fruit yield of 91.9 % nd 88.8 %, respectively. On the other hnd, during 2004/2005 cropping seson, % mrketle fruit yield which ws otined with the ppliction of 110 kg N + 120

6 108 Act griculture Slovenic, 91-1, mj 2008 kg P 2 O 5 /h (87.7 %) did not significntly differ from tht otined with the ppliction of 80 kg N + 90 kg P 2 O 5 /h (85.5 %), ut oth of these fertilizer rtes gve significntly higher % mrketle fruit yield when compred to the ppliction of the lowest rte (50 kg N + 60kg P 2 O 5 per hectre), which gve 81.6 % men mrketle fruit yield. The higher mrketle fruit yield under higher NP rte might hve een chieved proly ecuse the higher NP rte might hve improved fruit size therey contriuting to greter mrketle fruit yield per plot. However, so fr no report ws found on the influence of NP fertilizers on mrketle nd % mrketle fruit yields prcticlly for tomto to sustntite the present finding. Spcing Similr to fertilizer rte, spcing lso significntly influenced mrketle fruit yield nd % mrketle fruit yield (P<0.001) (Tles 1 nd 2). During oth cropping sesons, spcing of 80 cm x 30 cm nd 60 cm x 45 cm resulted in significntly higher men mrketle fruit yield s compred to 100 cm x 30 cm (Figure 5). The tomto cultivrs lso produced significntly different % mrketle fruit yields t ll spcing nd spcing of 80 cm x 30 cm gve the highest men % mrketle fruit yield followed y spcing of 60 cm x 45 cm wheres wider spcing of 100 cm x 30 cm gve the lowest men % mrketle fruit yield during oth sesons (Figure 6). Teerpolvichitr (1983) lso reported the highest mrketle fruit yield t closer spcing thn t wider spcing, which supports the present finding. However, Godfrey-Sm-Aggrey et l., (1985) nd Mehl et l., (2000) reported incresed mrketle fruit yield t wider spcing which contrdicts with the present finding. The higher mrketle fruit yield t closer spcing in the current investigtion could e due to reduced numer of sunscld fruits s hs een reported y Mohmed nd Ali (1986). Cultivrs: There ws no significnt effect of cultivrs on mrketle fruit yield during oth cropping sesons (P>0.05) (Tles 1 nd 2). However, significnt effect of cultivr on % mrketle fruit yield ws oserved during 2003/2004 cropping seson (Tle 1) with Melk shol producing significntly higher men % mrketle fruit yield (men dt not shown). On the other hnd, Wrner (2003) hve oserved significnt effect of cultivr on mrketle fruit yield of tomto during his first yer experiment ut this ws not repeted in his second nd third yer experiments. The significnt % mrketle fruit yield in the present investigtion could e due to the greter cnopy nd growth hit of this determinte cultivr (Melk shol) to cover the fruits from sun sclding therey contriuting to reduced unmrketle fruit yield record of this cultivr. Interction effect: During 2003/2004 cropping seson, significnt fertilizer*spcing interction effect ws oserved on % mrketle fruit yield (Tle 1). According to the result, t lower fertilizer rtes of 80 kg N + 90 kg P 2 O 5 nd 50 kg N + 60 kg P 2 O 5 per hectre, plnt spcing of 80 cm x 30 cm nd 60 cm x 45 cm produced significntly higher % mrketle fruit yield s compred to wider spcing of 100 cm x 30 cm (Tle 5).

7 BALEMI, T.: Response of tomto cultivrs differing in growth hit to nitrogen 109 On the other hnd, t the highest fertilizer rte of 110 kg N kg P 2 O 5 /h, the men % mrketle fruit yield significntly differed for ll spcing nd the highest nd lowest men % mrketle fruit yield ws produced t spcing of 80 cm x 30 cm nd 100 cm x 30 cm, respectively. 3. Effect of min fctors on plnt height (plnt vigour) All the min fctors hd highly significnt effect on plnt height 60 dys fter trnsplnting (P<0.001). However, there ws no interction effect for ny of the min fctor (Tle 3). An indeterminte cultivr Mrgeloe hd significntly higher men plnt height (72.8 cm) thn determinte cultivr, Melk shol (64.9 cm) (Tle 4). The significnt difference in plnt height etween the two cultivrs could e due to their distinct growth hit. Plnt height ws lso significntly ffected y the rtes of fertilizer pplied (P<0.001). All the three fertilizer rtes differed significntly from ech other in influencing plnt height with 110 kg N kg P 2 O 5 per hectre resulting in the highest men plnt height (81.7 cm) followed y 80 kg N + 90 kg P 2 O 5 /h (71.2 cm) s compred to the lowest fertilizer rte (50 kg N + 60 kg P 2 O 5 per hectre) which resulted in men plnt height of only (53.8 cm) which ws significntly lower compred to the ove two (Tle 4). Plnt height ws lso significntly influenced y spcing (P<0.001). Closer spcing of 60 cm x 45 cm nd 80 cm x 30 cm resulted in significntly higher plnt height compred to wider spcing of 100 cm x 30 cm (Tle 4). Ming (1995) nd Gupt nd Shukl (1977) lso reported incresed plnt height in tomto t closer spcing thn t wider spcing which is in line with the present result. 4. Effect of min fctors on numer of fruits per cluster The two cultivrs differed significntly in totl fruit numer per cluster (P<0.001), Melk shol on verge producing more numer of fruits per cluster (5.9 fruits/cluster) nd Mrgeloe producing less numer of fruits per cluster (4.5 fruits per cluster) (Tle 4). Moreover, fertilizer rte lso significntly ffected numer of fruits per cluster (P<0.001) nd the tomto cultivrs showed significnt vrition in this prmeter for ll levels of fertilizers pplied. The highest numer of fruits per cluster (5.97) ws otined with the ppliction of 110 kg N kg P 2 O 5 /h wheres the lowest rtes of fertilizers resulted in the lowest numer of fruits per cluster (4.39) (Tle 4). This, however, contrdicts with the report of Rshid (1993) who did not oserve significnt effect of fertilizer rte on numer of fruits per cluster t higher NP rte in his study. The highest numer of fruits per cluster t high NP rte in this study could e due to the positive effect, especilly of P, on flower formtion nd susequent fruit formtion. Likewise, fruit numer per cluster ws lso significntly influenced y spcing, the wider spcing of 100 cm x 30 cm resulting in significntly more numer of fruits per cluster s compred to closer spcing of 60 cm x 45 cm (Tle 4). A spcing of 80 cm x 30 cm, however, did not significntly differ from the other spcing in influencing fruit numer per cluster. Nevertheless, no cler trend of effect of spcing on numer of fruits per cluster could e illustrted ccording to the result of the present investigtion.

8 110 Act griculture Slovenic, 91-1, mj Effect of min fctors on verge weight of 10 fruits Ten fruit weight ws significntly ffected y ll min fctors (cultivrs, fertilizer rte nd spcing) (P<0.001 in ll cses) (Tle 3). Mrgloe, gve significntly higher men vlue of ten fruit weight (1.54 kg) compred to Melk shol (0.85 kg) nd this ws purely due to the genetic difference in fruit size of the two cultivrs. Ji (1992) lso similrly oserved significnt difference in verge fruit weight etween tomto cultivrs differing in growth hit, the indeterminte cultivr showing higher verge fruit weight thn the determinte cultivr, which ws similr to the present oservtion. With regrd to the effect of fertilizer rte, the ppliction of 110 kg N kg P 2 O 5 /h nd 80 kg N + 90 kg P 2 O 5 /h resulted in significntly higher men vlue of ten fruit weight (1.31 kg nd 1.23 kg, respectively) of the tomto cultivrs s compred to the ppliction of the lowest rte of fertilizer (50 kg N + 60 kg P 2 O 5 /h) which gve men ten fruit weight vlue of 1.05 kg (Tle 4). This result is lso in line with erlier report of Shrm et l., (1999) who recorded greter verge tomto fruit weight with the ppliction of higher NP fertilizers rtes. Contrry to the present result, Rshid (1993) did not oserve ny significnt influence of fertilizer rtes on this prmeter in his study. The highest men vlue of ten fruit weight (1.41 kg) of the tomto cultivrs ws otined t wider spcing of 100 cm x 30 cm wheres the lowest vlue (1.02 kg) ws recorded t spcing of 60 cm x 45 cm, which were significntly different (Tle 4). This result ws in line with the erlier report of Ali (1997) who found higher verge fruit weight t wider spcing s compred to closer spcing. Ji (1992), however, did not oserve ny significnt influence of spcing on verge fruit weight of oth determinte nd indeterminte types of tomtoes in his study. Additionlly, cultivr*spcing interction effect ws lso detected s significnt for the prmeter under discussion (P<0.05) (Tle 3). For Mrgeloe the men vlue of ten fruit weight significntly differed t ll plnt spcing investigted (Tle 6). For this cultivr significntly higher men vlue of ten fruit weight ws otined t plnt spcing of 100 cm x 30 cm (1.8 kg) while the lowest men vlue of ten fruit weight (1.3 kg) ws otined t plnt spcing of 60 cm x 45 cm (Tle 6). On the other hnd, for Melk shol except for spcing of 100 cm x 30 cm, which produced significntly higher ten fruit weight (1.03 kg), the other two spcing did not result in significntly different men vlue of ten fruit weight (0.77 kg nd 0.76 kg, respectively). Acknowledgment The Author cknowledges Mrs. Etgegn Teshome for her technicl ssistnce right from plnting up to field dt collection. The uthor lso cknowledges Mr. Bekele Tddesse, nd Mr. Ashenfi Chk, the teching stff in the horticulture section of Amo University College, for the follow up of the experiment during my sence. Thnks should lso go to Amo University College for finncing this reserch.

9 BALEMI, T.: Response of tomto cultivrs differing in growth hit to nitrogen Men totl fruit yield (kg plot -1 ) c 2003/4 cropping seson 2004/5 cropping seson kg N + 60 kg P2O5 80 kg N + 90 kg P2O5 110 kg N kg P2O5 Fertilizer rte pplied Figure 1. Totl fruit yield of tomto cultivrs s ffected y fertilizer rte during oth cropping sesons Men mrketle fruit yield (kg plot -1 ) kg N + 60 kg P2O5 80 kg N + 90 kg P2O5 110 kg N kg P2O5 Fertilizer rte pplied Figure 2. Mrketle fruit yield of tomto cultivrs s influenced y fertilizer rte during oth cropping sesons 2003/4 cropping seson 2004/5 cropping seson

10 112 Act griculture Slovenic, 91-1, mj Men % mrketle fruit yield c 2003/4 cropping seson 2004/5 cropping seson kg N + 60 kg P2O5 80 kg N + 90 kg P2O5 110 kg N kg P2O5 Fertilizer rte pplied Figure 3. Percent mrketle fruit yield of tomto cultivrs s ffected y fertilizer rte during oth cropping sesons 90 Men totl fruit yield (kg plot -1 ) /4 cropping seson 2004/5 cropping seson cm x 45 cm 80 cm x 30 cm 100 cm x 30 cm Spcing Figure 4. Totl fruit yield of tomto cultivrs s ffected y spcing during oth cropping sesons

11 BALEMI, T.: Response of tomto cultivrs differing in growth hit to nitrogen 113 Men mrketle fruit yield (kg plot -1 ) cm x 45 cm 80 cm x 30 cm 100 cm x 30 cm Spcing Figure 5. Mrketle fruit yield of tomto cultivrs s ffected y spcing during oth cropping sesons 2003/4 cropping seson 2004/5 cropping seson 100 Men % mrketle fruit yield /4 cropping seson c 2004/5 cropping seson c cm x 45 cm 80 cm x 30 cm 100 cm x 30 cm Spcing Figure 6. Percent mrketle fruit yield of tomto cultivrs s ffected y spcing during oth cropping sesons

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13 BALEMI, T.: Response of tomto cultivrs differing in growth hit to nitrogen 115

14 116 Act griculture Slovenic, 91-1, mj 2008

15 BALEMI, T.: Response of tomto cultivrs differing in growth hit to nitrogen 117 Tle 4: Effect of min fctors on plnt height, numer of fruits per cluster nd 10 fruit weight of tomto cultivrs Min fctors Men plnt height (cm) Men numer of fruits per cluster Men 10 fruit weight (kg) Cultivr Mrgeloe Melk shol LSD (5 %) Fertilizer 50 kg N +60 kg P 2 O 5 80 kg N +90 kg P 2 O kg N+120 kg P 2 O 5 LSD (5 %) Spcing 60 cm x 45 cm 80 cm x 30 cm 100 cm x 30 cm LSD (5 %) c c c Mens for ech min fctor in the sme column followed y the sme letter re not significntly different from ech other t ( = 0.05) ccording to Tukey test Tle 5: Interction effect of fertilizer rte nd spcing on % mrketle fruit yield of the tomto cultivrs Fertilizer rte Spcing % Mrketle fruit yield 50 kg N + 60 kg P 2 O 5 80 kg N + 90 kg P 2 O kg N kg P 2 O 5 60 cm x 45 cm 80 cm x 30 cm 100 cm x 30 cm LSD (5 %) 60 cm x 45 cm 80 cm x 30 cm 100 cm x 30 cm LSD (5 %) 60 cm x 45 cm 80 cm x 30 cm 100 cm x 30 cm LSD (5 %) c 2.1 Mens for ech fertilizer rte in column followed y the sme letter re not significntly different from ech other t ( = 0.05) ccording to Tukey test

16 118 Act griculture Slovenic, 91-1, mj 2008 Tle 6: Interction effect of cultivr nd spcing on men vlue of 10 fruit weight Cultivr Spcing 10 fruit weight (kg) Mrgloe 60 cm x 45 cm 1.3 c 80 cm x 30 cm cm x 30 cm 1.8 LSD (5 %) 0.19 Melk shol 60 cm x 45 cm 80 cm x 30 cm 100 cm x 30 cm LSD (5 %) Mens for ech cultivr in column followed y the sme letter re not significntly different from ech other t ( = 0.05) ccording to Tukey test REFERENCES Ali, S.M.R Effect of Plnt Popultion Density on Tomto. ARC Trining Report. pp 1-3. FAO Production yer ook. Godfrey-Sm-Aggrey, W. Turuwork A. nd Tdelle A Review of Tomto Reserch in Ethiopi nd Proposl for future Reserch nd Development direction. In: Godfrey-Sm-Aggrey nd Bereke Tsehi (eds.). Proceedings of the First Ethiopin Horticulturl Workshop. pp Gupt, A. nd Shukl, V Response of tomto to plnt spcing, nitrogen, phosphorus nd potssium fertilizer. Indin J. Hort.34 (3): Hmid, M Effect of Plnt Density on Tomto Yield. ARC Trining Report. pp Jnury, Ji, L. W Plnt Density Effect on Different Types of Tomto. ARC Trining Report. pp 1-5. Lemm, D., Yyeh, Z. nd Herth, E Agronomic Studies in Tomto nd Cpsicum. In: Herth nd Lemm (eds.). Horticulture Reserch nd Development in Ethiopi: Proceedings of the Second Ntionl Horticulturl Workshops of Ethiopi. 1-3 Decemer. Addis A, Ethiopi. pp Ming, E.W Pruning nd Spcing Effect on Tomto vr. Seed Nm Khem. ARC Trining Report. pp1-4. Mehl, C.P., Srivstv, V.K., Jge, S., Mngt, R., Singh, J. nd Rm, M Response of tomto vrities to N nd P fertiliztion nd spcing. Indin Jornl of Agriculturl Reserch. 34 (3): Mohmed, S.F nd Ali, Z.E Effect of in-row Plnt Spcing nd Levels of Nitrogen Fertilizer on Yield nd Qulity of Direct Seeded Tomtoes. Astrct. Symposium on Tomto Production on Arid Lnd. Act Horticulture 190 (1). Nssr, H.H Effect of Plnting Pttern, Plnting popultion nd Nitrogen level on Yield nd qulity of Tomto. Astrct. Symposium on Tomto Production on Arid Lnd. Act Horticulture 190 (1).

17 BALEMI, T.: Response of tomto cultivrs differing in growth hit to nitrogen 119 Pndey, R.P, Solnki, P.N, Srf R.K nd Prihr, M.S Effect of Nitrogen nd Phosphorus on growth nd yield of tomto vrieties. Punj Vegetle Grower. 31: 1-5. Rshid, M.D.A Effect of Fertilizer Rtes nd Time of Appliction on Yield of Tomto. ARC Trining Report. pp 1-3. Reeve, E nd Schmidth, W.A Influence of plnt spcing on cnning tomto yields. Proc. Amer. Soc. Hort. Sci. 59: Shrm, K.C., Singh, A.K. nd Shrm, S.K Studies on Nitrogen nd Phosphorus requirement of tomto hyrids. Annls of Agriculturl Reserch. 20 (4): Teerpolvichitr, P Effect of Plnt Popultion Density on Tomto. ARC Trining Report. pp 1-4. Wrner, H Plnt Spcing nd Row Arrngement Affects Processing Tomto Yield. Agriculture nd Agri-Food Cnd. Ministry of Agriculture, Food nd Rurl Affirs. Zhr, M Influence of plnt density on yield of processing tomtoes for mechnicl hrvest. J. Amer. Soc. Hort. Sci.94 (4):