Optimization of Fertigation Frequency for Tomato Under Controlled Condition

A two years of experiment was conducted to study the effect of fertigation levels and schedules on yield, gross monetary returns and net monetary returns of tomato under polyhouse environment. The treatments include 3 fertigation levels (F₁-60% of RDF, F₂-80% of RDF, and F₃-100% of RDF) and 3 fertigation schedules (S₁-6 equal splits of RD of NPK at every 18 days interval, S₂-9 equal splits of RD of NPK at every 12 days interval, S₃-12 equal splits of RD of NPK at every 9 days interval). The results indicated that yield attributes viz., number of fruits plant⁻¹, fruit weight plant⁻¹ and tomato fruit yield unit⁻¹ of polyhouse (15.72, 14.07 and 14.90 t) were noticed significantly highest under fertigation of 100% RDF, however it was at par with 80% of RDF during both the years and on pooled mean. Similarly, fertigation of 100% RDF recorded significantly maximum gross monetary returns unit⁻¹ of polyhouse (Rs. 2, 20, 093, 2, 11, 064 and 2, 15, 578), net monetary returns unit⁻¹ of polyhouse (Rs. 1, 59, 810, 1, 50, 474 and 1, 55, 142) and B: C ratio (3.65, 3.48 and 3.57) over the rest of treatments, however it was at par with 80% of RDF during both the years. Among the fertigation schedules fertigation of 12 equal splits of NPK at every 9 days interval registered significantly maximum yield attributes viz., number of fruits plant¹, fruit weight plant⁻¹ and tomato fruit yield unit⁻¹ of polyhouse (15.56, 13.42 and 14.49 t) as compared to other treatments during both the years and on pooled mean. Significantly highest gross monetary returns unit⁻¹ of polyhouse (Rs. 2, 17, 837, 2, 01, 290 and 2, 09, 563), net monetary returns unit⁻¹ of polyhouse (Rs. 1, 58, 820, 1, 41, 967 and 1, 50, 394) and B: C ratio (3.68, 3.39 and 3.54) were recorded under fertigation of 12 equal splits of NPK at every 9 days interval up to 120 days after transplanting over rest of the treatments during both the years and on pooled mean. The lowest values of these parameters were noticed under fertigation of 60% RDF during the period of investigation during both the years. Based on two years of investigation and pooled mean it could be concluded that fertigation of 80% of RDF (240: 120: 120 N, P₂O₅, K₂O kg ha⁻¹) in 12 equal splits at every 9 days interval found most suitable to achieve maximum tomato fruit yield, net monetary returns and B: C ratio unit⁻¹ of polyhouse during summer season under naturally ventilated polyhouse condition.