Background

Summer squash (Cucurbita pepo L., 2n=2x=40), an economically important member of the gourd family, Cucurbitaceae. Summer squash is a warm season, New World vegetable crop, well adapted to temperate and sub-tropical region. It is a quick growing and early yielding cucurbit which performs well in cool and moist weather conditions and require approximately 16-27ºC temperature for its normal growth and development. Plant produce stem with greatly shortened internodes in close succession. It is a compact bushy plant with reduced size tendrils. Summer squash is also known as bush squash, vegetable marrow, Vilayati Kaddu/Chappan Kaddu/Safed Kaddu (Thamburaj and Singh, 2001). Summer squash ranks high in economic importance among vegetable crops. In the hills of Northern India, its cultivation is mostly confined to mid hills where summers are mild, the sowing season starts from March-April and the crop matures in May-June, whereas in lower hills where summers are a bit harsh and the crop is attacked severely by fruit fly and other insect pest and diseases. Therefore, this problem can be coped up by adopting protected cultivation and using short duration vegetable crops like cucurbits for the horticultural production. Inspite of favorable climatic condition in Uttarakhand, early growing season encounters with low temperature, frost etc. and later on unexpected drought, rainfed conditions and biotic stresses are some of the major constraints, which restrict vegetable grower to cultivate summer squash commercially in Uttarakhand by adversely affecting crop growth and yield.

Though state has a wide range of diverse agro climatic conditions but vegetable cultivation practices have generally been restricted to limited region and seasonal needs and the lack of awareness about technological advancement like protected cultivation and use of poor quality of planting material even in polyhouse are also responsible for low productivity of state as compared to national level (Singh et al., 2010). A number of improved cultivars have been recently developed in the country in this crop but no effort has been made so far to evaluate them for their suitability of growing under different protected conditions in Tarai region of Uttarakhand. In this context, varietal evaluation is felt essential to identify suitable varieties for its production with superior attributes.

1 Materials and Methods

The investigation was undertaken during November 2016-March 2017 and the experiment was conducted at Vegetable Research Centre (V.R.C.), Govind Ballabh Pant University of Agriculture & Technology, Pantnagar. It falls in the humid subtropical zone and geographically situated at latitude of 29.50° north, longitude of 79.30° east and at an altitude of 243.84 meters above the mean sea level. Pantnagar is situated in the foothills of Shivalik range of the Himalayas, in a narrow belt called Tarai. Maximum temperature ranging from 32ºC to 43ºC in summer and minimum temperature ranging from 0ºC to 9ºC in winter has been recorded.

The experiment was laid out in Two Factorial Randomized Block Design with three replications. First factor included two growing conditions i.e. naturally ventilated polyhouse and open growing condition with plastic mulch, whereas the second factor comprises of ten varieties of summer squash collected from different sources viz. Cora (Check), Cheongma Zuchhini, Champion, ASV-3098, Long Green, Golden Yellow, Yellow Zuchhini, Green Star, Sunny House and Catherina. Seedlings were raised in polybags and transplanted 15 days after sowing at a spacing of 90 cm × 60 cm. Silver color plastic mulch of 25 micron thickness was used in open condition. Observations for growth and yield attributes were recorded using standard techniques. The economics of summer squash was worked out based on inputs and operational cost incurred since seed sowing to harvest of fruits including marketing. The data recorded for both the year was analyzed using software TNAU STAT.

2 Results

2.1 Yield and yield attributes

Data on yield, average fruit weight, number of fruits per plant and number of harvesting of ten varieties of summer squash were analyzed (Table 1). Among different varieties under polyhouse conditions, maximum fruit yield was obtained in Cora (1033.72 q/ha) followed by Sunny House (882.28 q/ha), Catherina (828.78 q/ha) and Champion (715.21 q/ha). While, in open growing condition, Champion was best performer (517.18 q/ha) closely followed by Cheongma Zucchini (478.48 q/ha). Under polyhouse, maximum average fruit weight was recorded in variety Long Green (1320 g) and minimum in variety Yellow Zucchini (713.33 g). In open condition, maximum fruit weight obtained in Catherina (1079 g) and minimum in ASV-3098 (495.33 g).

As far as performance of summer squash with respect to number of fruits per plant is concerned, it was significantly influenced by growing conditions. It was significantly higher in polyhouse and maximum 4.62 fruits/plant recorded in Cora and Sunny House, which also influenced number of harvestings positively and 5.66 and 6.00 harvest were taken from the two varieties respectively. Whereas, only 2.33 harvestings were obtained from the variety Long Green which has minimum (0.49) number of fruits/plant. Similarly, in open growing condition, varieties with more number of fruits i.e. Yellow Zucchini (3.07), Cheongma Zucchini (2.87) and Champion (2.81) provided more number of harvestings viz. 6.00, 5.33 and 5.33 respectively.

2.2 Economic feasibility

The maximum cultivation cost of Rs. 7,62,250/ha in this study was incurred in variety Cora under naturally ventilated polyhouse whereas in open growing condition with plastic mulch maximum and minimum costs of cultivation were worked out in varieties Yellow Zucchini (Rs. 2, 85, 775) and ASV-3098 (Rs. 2, 53, 775) respectively (Table 2). The gross and net returns in different varieties were worked out based on prevalent wages, rate of critical inputs and average selling price of produce.

Under polyhouse highest gross return (Rs. 15, 50, 580), net profit (Rs. 7, 88, 330) and benefit-cost ratio (2.03) were obtained from Cora and lowest B/C ratio in Long Green (0.31). In open growing conditions with plastic mulch maximum net profit (Rs. 5, 07, 495) was obtained in Champion (2.89). Similar findings were also been reported by Thapliyal et al. (2014) and Singh et al. (2015).

Higher values of gross return was obtained under naturally ventilated polyhouse in comparison to mulched condition in open climate but net return and B: C ratio were found higher in open climate with plastic mulch because polyethylene mulch provide optimum micro climate for better plant growth at a lower cost of cultivation than naturally ventilated polyhouse due to no structural cost. Reason for higher gross return in naturally ventilated polyhouse is moderate temperature and relative humidity maintenance and fewer incidences of viral diseases and insect-pests. Whereas, net return was less due to structural cost of polyhouse establishment.

3 Discussion

The performance of summer squash was significantly influenced by growing conditions with respect to number of fruits per plant. It was significantly higher in polyhouse and maximum fruits/plant recorded in Cora and Sunny House, which also influenced number of harvestings positively. Similarly, in open growing condition, varieties with more number of fruits i.e. Yellow Zucchini, Cheongma Zucchini and Champion provided more number of harvestings. These results have similarities with results obtained from the findings of Dev (2011) and Bhatt et al. (2016) working on summer squash.

Under polyhouse highest gross return, net profit and benefit-cost ratio were obtained from Cora and lowest B/C ratio in Long Green. In open growing conditions with plastic mulch maximum net profit was obtained in Champion. Similar findings were also been reported by Thapliyal et al. (2014) and Singh et al. (2015).

4 Conclusion

Based on the findings of present investigation, it could be concluded that under tarai condition of Uttarakhand, summer squash variety Cora when grown under naturally ventilated polyhouse provided maximum net return with high cost of cultivation, still it was most suited variety for polyhouse growing condition due to high B/C ratio. In open growing condition with plastic mulch variety Champion proved to be most profitable. Hence, recommended for commercial cultivation of summer squash at farmers field.

Authors’ contributions

Each author has equally contributed to this paper. All authors read and approved the final manuscript.

Acknowledgments

Thanks to the Department of Vegetable Science, GBPUAT, Pantnagar for providing necessary facility for this research project. Also thanks to UKS Kushwaha for his critical comments to shape this paper.

References

Bhatt L., Maurya S.K., and Singh D., 2016, Economic feasibility of summer squash cultivation using low tunnel and black plastic mulch under tarai condition of Uttarakhand, Journal of Applied and Natural Science, 8(2): 817-821

Dev H., 2011, Response of summer squash varieties to planting time in lower hills of Himachal Pradesh, Agricultural Science Digest, 31(2)

Singh P.K., Maurya S.K., Singhal P., and Joshi G., 2010, Performance of Summer squash for off season cultivation under protected condition in tarai region of Uttarakhand, National Seminar on Protected Cultivated of Vegetables and Flowers-A value chain approach (11-12 January, 2012; Pantnagar, India), Book of Abstracts., 12

Singh M., Bhatt L., Singh V.P., Maurya S.K., and Singh A.K., 2015, Effect of transplanting dates and mulching materials on growth, yield and economics of summer squash in Uttarakhand hills, Indian Journal of Agricultural Science., 12: 1529-1533

Thamburaj S., and Singh N., 2001, Textbook of vegetables, Tuber crops and Spices, Indian Council of Agricultural Research, New Delhi, 286p

Thapliyal P., Bhatt L., Uniyal S.P., and Maurya S.K., 2014, Effect of soil, moisture regimes and mulch materials on growth, yield and economics of summer squash in Uttarakhand hills, Vegetable Science, 41(2): 184-187