The Effects of Plant Density on the Productivity of Tomato Hybrids in a Newly Developed Low Cost Naturally Ventilated Greenhouse

Looking into the variations in the design of greenhouses and cost factor, a two-span saw tooth type low cost naturally ventilated greenhouse (NVG) of 250 m2 area was designed and developed. The galvanized iron (GI) framed NVG covered with 200µ ultra-voilet (UV) stabilized plastics sheet, consisted of cross and ridge ventilation, shade net, fogging and drip irrigation systems. Effect of spacing and tomato hybrid on yield and yield attributing traits of tomato were studied under NVG. Twenty-three days old seedlings of four tomato hybrids viz. Rupali, Pusa Hybrid-2, Naveen 2000 and Avinash-2 were transplanted at three different spacing (60 x 60 cm, 45 x 45 cm and 60 x 45 cm) inside the NVG. The results showed that increasing the spacing significantly increased the number of fruits, average fruit weight, fruit yield per plant, yield per unit area (kg/m2) and marketable fruit yield per plant. It was noted that the significantly highest fruit yield was recorded under wider spacing of 60 x 60cm over other spacings. Among the different tomato hybrids, Naveen-2000 significantly produced higher yield (12.55 kg/m2) and yield attributes over other and statistically at par with Avinash (12 kg/m2). The developed NVG was indigenous, simple to erect and performed well for tomato crop production. The efforts will enhance the application of greenhouse in arid and semi-arid regions of India.