Bulletin UASVM Horticulture, 67(1/2010 Print ISSN 1843-5254; Electronic ISSN 1843-5394 The Influence of Plant Density and Shoot Pruning on of Bell Pepper Cultivated in Plastic Tunnel Danut MANIUTIU, Rodica SIMA, Alexandru S. APAHIDEAN, Maria APAHIDEAN, Diana FICIOR Faculty of Horticulture, University of Agricultural Sciences and Veterinary Medicine, 3-5 Manastur Street, 400372, Cluj-Napoca, Romania; dan_maniutiu@yahoo.com, rodiganea@yahoo.com Abstract. The aim of the experiment effectuated at the company SC Cristal Lux SRL from Bălan commune, Sălaj County, Romania, was to establish the best plant density and plant directing method for bell peppers cultivated in plastic tunnel. A bifactorial experience has been organized: Factor A = plant density, with: a 1 30000 plants/ha; a 2 40000 plants/ha; Factor B = shoots pruning method, with: b 1 pruned with 2 shoots; b 2 pruned with 3 shoots. By factors combination 4 experimental variants resulted. Plants density has affected both the early and the total yield. A density of 40000 plants/ha assured a significant yield increase comparative with 30000 plants/ha. The pruning method has influenced neither early nor total yield. Under the combined influenced of both factors the best results have been obtained by variant III (40000 plants/ha, 2 shoots and variant IV (40000 plants/ha, 3 shoots for both the early and the total yield. Keywords: Capsicum annuum, fructification, stem training, number of plants, bell pepper INTRODUCTION Bell pepper represents one of the main vegetables cultivated in plastic tunnels. Very favourable conditions for bell pepper culture are in the south and west of Romania. The research effectuated in Bălan commune, Sălaj County it had in view the behaviour of bell pepper under influence of plant density and shoot pruning method in a less favourable area for bell pepper culture. Researches concerning plant density and shoot pruning method at bell pepper have been done also by other researchers. Thus, Joliffa and Gaye (1995 established that gradually increasing of plant density from 1.4 plant/m 2 to 11.1 plants/m 2 determined bigger productions. Lorenzo and Castilla (1995 did experiments in plastic tunnel and obtained 4.78 kg/m 2 at 2.0 plants/m 2 and 6.13 kg/m 2 at 3.2 plants/m 2. Cebula (1995 had cultivated in a greenhouse bell pepper at two densities: 1.5 and 8 plants/m 2 and pruned the plants with 1 shoot respectively with 4 shoots and obtained the best results in the case of variant with higher density and pruned with one shoot. Jovicich et. al. (2004 studied also the influence of plant density on bell pepper cultivated in greenhouse on perlite substratum and noticed that increasing the plant density from 1.5 plants/m 2 to 3.8 plants/m 2 determined the increase of yield from 3.5 kg/m 2 to 7.4 kg/m 2 without a significant diminish of fruit quality. 259
MATERIALS AND METHODS The hybrid used in the culture was Belladona F 1, which seeds are produced by Seminis Company. Belladona F 1 is an early bell-pepper hybrid. Plants have an undetermined growth, are compact, vigorous and give and uniform, very early yield. Belladona F 1 has a high percent of fruits with four lobes, very firm and with thick pulp, about 6-7 mm. Fruits are easy to reap, weight in average 160-200 g and have 9/10 or 8/9 cm dimensions. Hybrid is high efficiently due to both vegetation period and uniform yield with excellent quality fruits. In nowadays Belladona F 1 is one of the most performance yellow-white hybrids on the market. It is also resistant to Tobamo (Tobamovirus strain P0. It is recommended for spring, summer and autumn cultures both in field and protected spaces. In order to establish the stem training method for bell pepper cultivated in plastic tunnels, a bifactorial experience has been organized: Factor A = plant density, with 2 graduations: a 1 30000 plants/ha; a 2 40000 plants/ha. Factor B = stem training method, with 2 graduations: b 1 pruned with 2 shoots; b 2 pruned with 3 shoots. By factors combination, 4 experimental variants resulted. The culture was established with seedling produced in cells with 7 cm diameter. The sowing was done in second decade of February. s I and II were planted at 80/32 cm distances that assured a density of 30000 plants/ha meanwhile variants III and IV were planted at 80/42 cm distances resulting a density of 40000 plants/ha. Plants from variants I and III were pruned with 2 shoots and plants from II and IV variants with 3 shoots, fruits were allowed to grow only on those shoots. The other technological works were common for all variants. RESULTS AND DISCUSSION Early yield Under unilateral influence of plant density on early yield (31.07.2009 at bell peppers cultivated in plastic tunnels (Tab. 1 it can be noticed that variants with 40000 plants/ha realized an yield increase about 11.6%, significant comparative with the variants with 30000 plants/ha. Tab. 1 The unilateral influence of plants density on early yield (31.07.2009 at bell peppers cultivated in plastic tunnels 30000 plants/ha 3.33 100.0 - - 40000 plants/ha 3.71 111.6 0.39 x LSD 5% 0.23 LSD 1% 0.53 LSD 0.1% 1,70 Analyzing the influence of shoots pruning method on early yield (31.07.2009 at bell peppers cultivated in plastic tunnels (Tab. 2 it was found that plants from variants pruned with 3 shoots registered a yield about 0.18 kg/m 2 comparative with variants pruned with 3 shoots but the s it is not statistical assured. 260
Tab. 2 The unilateral influence of shoots pruning method on early yield (31.07.2009 at bell peppers cultivated in plastic tunnels (kg/m 2 % Difference Significance of 2 shoots 3.43 100.0 - - 3 shoots 3.61 105.1 0.18 - LSD 5% 0.23 LSD 1% 0.38 LSD 0.1% 0.72 Regarding the combined influence of both factors on early yield (31.07.2009 at bell peppers cultivated in plastic tunnels (Tab. 3 it can be noticed that variant IV (40000 plants/ha and 3 shoots and variant III (40000 plants/ha and 2 shoots realized yield increases about 17.2% respectively 11.2%, s being distinct significant respectively significant given the control (30000 plants/ha and 2 shoots. II (30000 plants/ha and 3 shoots recorded too a yield increase about 4.6% comparative to control but the was not statistical assured. Tab. 3 The combined influence of both factors on early yield (31.07.2009 at bell peppers cultivated in plastic tunnels I 30/2 3.25 100.0 - - II 30/3 3.40 104.6 0.15 - III 40/2 3.61 111.2 0.36 x IV 40/3 3.81 117.2 0.56 xx LSD 5% 0.33 LSD 1% 0.54 LSD 0.1% 1.01 Total yield Like in the case of early yield, under the unilateral influence of plants density (Tab. 4 the highest total yield was recorded for 40000 plants/ha density with an yield increase about 10.7%, significant comparative with the variants with 30000 plants/ha density. Tab. 4 The unilateral influence of plants density on total yield at bell peppers cultivated in plastic tunnels 30000 plants/ha 8.11 100.0 - - 40000 plants/ha 8.97 110.7 0.87 x LSD 5% 0.58 LSD 1% 1.33 LSD 0.1% 4.24 Neither in the case of total yield there were not s between fruition on 2 or 3 shoots, yield s between variants being not statistically assured (Tab. 5. Still fruition on 3 shoots assured a 5.1% yield increase comparative with fruition on 2 shoots. 261
Tab. 5 The unilateral influence of shoots pruning method on total yield at bell peppers cultivated in plastic tunnels (kg/m 2 % Difference Significance of 2 shoots 8.33 100.0 - - 3 shoots 8.75 105.1 0.42 - LSD 5% 0.56 LSD 1% 0.93 LSD 0.1% 1.74 Under combined influence of both factors on total yield at bell peppers cultivated in plastic tunnels (Tab. 6 plants from variant IV (40000 plants/ha and 3 shoots and variant III (40000 plants/ha and 2 shoots realized positive significant yield s given the control (30000 plants/ha and 2 shoots. The yield increase about 4.4% for variant II (30000 plants/ha and 3 shoots was not statistically assured. Tab. 6 The combined influence of both factors on total yield at bell peppers cultivated in plastic tunnels I. 30/2 7.93 100.0 - - II. 30/3 8.28 104.4 0.35 - III. 40/2 8.73 110.1 0.80 x IV. 40/3 9.22 116.3 1.29 x LSD 5% 0.80 LSD 1% 1.32 LSD 0.1% 2.47 Commercial quality of fruits Regarding commercial quality of bell pepper production (Tab. 7 it was found that percent of first quality fruits was between 84.86% and 90.99% with big s between experimental variants. IV (40000 plants/ha and 3 shoots realized the highest percent of first quality fruits (124.66% comparative with the control due to the higher yield. Tab. 7 Commercial quality of bell pepper production under influence of plant density and shoots pruning method Production (kg/ha % first quality Second From Comparative with Total First quality quality total the control I. 30000 plants/ha with 2 shoots 7.93 6.73 1.20 84.86 100.00 II. 30000 plants/ha with 3 shoots 8.28 7.15 1.13 86.35 106.24 III. 40000 plants/ha with 2 shoots 8.73 7.89 0.84 90.37 107.24 IV. 40000 plants/ha with 3 shoots 9.22 8.39 0.83 90.99 124.66 262
CONCLUSIONS After the experiment effectuated in 2009 regarding the influence of plant density and shoots pruning method on the bell pepper cultivated in plastic tunnel the following conclusions can be inferred: In the case of both early and total yield variants with 40000 plants/ha density recorded yield increases distinct significant respectively significant comparative with the variants cultivated at 30000 plants/ha density. The shoots pruning method did not influenced significant the yield. Under the combined influence of factors, both early and total yield were higher in the case of variant IV (40000 plants/ha and 3 shoots and variant III (40000 plants/ha and 2 shoots. Neither plant density nor directing method did not significant influence the commercial quality of fruits. It is recommended the density of 40000 plants/ha pruned with 3 shoots for bell peppers culture in plastic tunnels. REFERENCES 1. Cebula, S. (1995. Optimization of plant and shoot spacing in greenhouse production of sweet pepper. Acta Horticulturae (ISHS. 412: 321-329. 2. Lorenzo, P. and N. Castilla (1995. Bell pepper yield response to plant density and radiation in unheated plastic greenhouse. Acta Horticulturae (ISHS. 412:330-334. 3. Jollife, P. A. and M. M. Gaye (1995. Dynamics of growth and yield component responses of bell peppers (Capsicum annuum L. to row covers and population density. Scientia Horticulturae. 63 (3: 153-164. 4. Jovicich, E., D. J. Cantliffe and G. J. Hochumth (1999. Plant density and shoot pruning on yield and quality of a summer greenhouse sweet pepper crop in Northcentral Florida. North Central Florida Proceedings 28 th National Agricultural Congress. p: 184-190. 5. Jovicich, E., D. J. Cantliffe and P. J. Stofella (2003. Spanish pepper trellis system and high plant density can increase fruit yield, fruit quality and reduce labour in a hydroponic passiveventilated greenhouse. Acta Horticulturae (ISHS. 614:255-262. 6. Jovicich, E., D. J. Cantliffe and P. J. Stofella (2004. Fruit yield quality of greenhousegrown bell pepper as influenced by density, container and trellis system. Hortehnology. 14(4: 507-513. 263