Effect of Fertigation Levels and Different Spacings on Yield and Yield Attributes of Bell Pepper (Capsicum annuum L.var.grossum sendt.) in Polyhouse condition

An experiment was carried out in bell pepper (Capsicum annuum L.var.grossum sendt.) to study the influence of fertigation levels and different spacings on yield and yield attributes under polyhouse condition.The perusal of the data revealed that widely spaced (45 cm x 60 cm) plants produced the highest number of fruits plant-1 (13.75), fruit girth (25.23 cm) and fruit yield plant-1 (1.53 kg) while fruit yield m-2 (8.92 kg) was the highest for closely spaced (45 cm x 30 cm) plants. Yield and yield attributes were significantly influenced by fertigation levels. Among the fertigation levels, 100 % adhoc recommendation of KAU for precision farming (230: 25: 250 N, P2O5 and K2O kg ha-1) registered the highest number of fruits plant-1(15.15), fruit girth (26.24 cm), fruit yield plant-1 (1.72 kg) and fruit yield m-2 (8.30 kg).


INTRODUCTION
Bell pepper (Capsicum annuum L.var.grossum sendt.) also known as capsicum, sweet pepper or shimla mirch is one among the most popular vegetables grown in polyhouses worldwide. The bell pepper fruits are available in different attractive colours and they have great demand in markets. Bell pepper is rich in proteins, vitamin A, ascorbic acid, riboflavin, thiamin, niacin and minerals like potassium, magnesium and calcium (Joshi and Singh, 1975). Being a cool season crop, year round production of quality bell pepper fruits is not possible in open field condition. Crops are more vulnerable to weather fluctuations in open field (Ochigbu and Harris, 1989) with more pests and diseases incidence leading to low productivity as well as quality. Protected cultivation techniques can be effectively utilized for the production of good quality produce with high productivity. Compared to open field cultivation, polyhouse cultivation resulted in 2-3 times yield enhancement in bell pepper (IIHR, 2011). Efficient and optimum application of fertilizer under protected condition ensures improved growth, yield and quality of bell pepper along with minimized loss of inputs and increased economic benefits. Adoption of appropriate plant spacing is one of the important aspects of successful crop production. Optimum plant spacing ensures proper growth and development of plants resulting in maximum yield of crop and economic use of land.

II. MATERIALS AND METHODS
A field trial was done to study the influence of fertigation levels and different spacings on yield and yield attributes of bell pepper under polyhouse condition. The soil of experiment plot was sandy clay loam, acidic in reaction, high in organic carbon and available phosphorus, low in available nitrogen and potassium. The study was laid out in split plot design with 12 treatment combinations replicated three times. The main plot treatments consisted of four levels of fertigation viz., 100 % adhoc recommendation of KAU for precision farming (F1), 50 % adhoc recommendation of KAU for precision farming (F2), 50 % adhoc recommendation of KAU for precision farming + foliar spray of combined solution of urea and potassium chloride each at 1.25 % at 30 and 60 DAT (F3) and 25 % adhoc recommendation of KAU for precision

III. RESULTS AND DISCUSSION
Among different fertigation levels F1 (100 % adhoc recommendation of KAU for precision farming) recorded the highest number of fruits plant -1 (15.15) followed by F3 (50 % adhoc recommendation of KAU for precision farming + foliar spray at 30 and 60 DAT) (13.49) and F2 (50 % adhoc recommendation of KAU for precision farming) (12.37). Maximum fruit girth (26.24 cm) was recorded from F1 and it was on par with F3 (25.24 cm) and significantly superior to F2 (23.89 cm) and F4 (22.25 cm). F1 also recorded higher fruit yield plant -1 (1.72 kg) and fruit yield m -2 (8.30 kg). Similar findings of increased yield in bell pepper with 252 kg N and 240 kg N was reported by Hartz et al. (1993) and Aliyu (2002) respectively. The increased availability of nutrients for the treatment F1 might have increased the photosynthate accumulation enhancing the yield attributes and yield. Similar finding of increased fruit weight, yield plant -1 and yield ha -1 with higher dose of NPK (250:200:200 kg ha -1 ) was reported by Shrivastava (1996).
Yield and yield attributes were significantly influenced by different plant spacings. The treatment S3 (45 cm x 60 cm) recorded the highest number of fruits plant -1 (13.75), fruit girth (25.23 cm) and fruit yield plant -1 (1.53 kg). The number of fruits plant -1 at 45 cm x 30 cm (S1) and 45 cm x 45 cm (S2) were 12.58, 12.67 respectively which were on par The lowest fruit girth was reported by S1 (23.33 cm) and it was on par with S2 (24.66 cm). Similarly lowest fruit yield plant -1 (1.30 kg) was obtained from S1 (45 cm x 30 cm) and it was on par with S2 (45 cm x 60 cm) (1.36 kg). Higher yield and yield attributes for S3might be due to higher availability of sunshine, more space and less competition for nutrients which in turn promoted more number of flowers and increased photosynthate accumulation. Similar results of higher yield and yield attributes with wider spacing in bell pepper were reported by Alam et al. (2011) and Biradar et al. (2014). Maximum total fruit yield m -2 was obtained from closely spaced plants (45 cm x 30 cm) (8.92 kg) followed by S2 (6.74 kg) and both the treatments were significantly superior over S3 (5.67). The higher plant population in closer spacing resulted in higher fruit yields m -2 compared to wider spacing. Similar findings of increased fruit yield ha -1 with closer spacing were reported by Zende (2008) and Shivakumar et al. (2012).

IV. CONCLUSION
The study revealed that for high yield and yield attributes the bell pepper plants should be treated with 100 % adhoc recommendation of KAU for precision farming. Among different spacing closer spacing of 45 cm x 30 cm is ideal for profitable cultivation of plants under polyhouse. Even though interaction of two treatments was not significant, higher net returns (₹ 1,88,956 10 cents-1) and B: C ratio (3.30) were recorded from the plants treated with 100 % adhoc recommendation of KAU for precision farming along with closer spacing of 45 cm x 30 cm (f1s1).