Optimizing Tomato (Solanum lycopersicum L.) Cultivation in a Naturally Ventilated Polyhouse: Impacts of Drip Irrigation and Fertigation on Root Growth, Nutrient Uptake, and Productivity

Abstract

The decline in agricultural production and shrinking per capita land holding has resulted in a thrust on vegetable production under protected environment. The efficient management of resources (i.e., water, nutrients etc.) plays an important role in sustainable production. Therefore, the experiment was conducted in naturally ventilated polyhouse at the experimental farm of CSKHPKV, Palampur, Himachal Pradesh with tomato as a test crop. The experiment was laid out in completely randomized design with 10 treatment combinations consisting of two drip irrigation levels viz., I1 (Irrigation was applied from week one to two based on 100% of pan evaporation (Epan), week three to eight based on 40% of Epan, week nine to fourteen based on 60% of Epan, week fifteen to twenty based on 80% of Epan, week twenty-one to twenty-four based on 100% of Epan) and I2 (Irrigation was applied based on 100% of Epan during whole the crop period) and five nutrient schedules viz., F1 (100% recommended dose of fertilizers (RDF) through conventional method, F2 (100% N through fertigation + PK through conventional method), F3 (100% NK through fertigation + P through conventional method), F4 (100% NPK through fertigation) and F5 (50% NPK through conventional method + 150% NPK through fertigation) replicated thrice. The results highlighted that the root length (316.53 cm), fruit yield (7.33 kg/m2) and net returns (Rs. 173.12) were significantly higher under I2 treatment as compared to I1 treatment. Among the nutrient schedules, root growth parameters, NPK uptake, fruit yield (7.62 kg/m2) and net returns (Rs. 177.80) were significantly higher under F5 treatment. However, the benefit:cost (B:C) ratio (3.75) was significantly higher under F4 treatment. The irrigation level I2 with fertigation treatment F4 (100% NPK through fertigation) performed better among all the treatment combinations and should be recommended for higher tomato production under naturally ventilated polyhouse in northwestern Himalayan region.