Synchronizing nitrogen and potassium supply with crop demand to enhance nutrient use efficiency and water use efficiency on Bt. cotton hybrid (NSPL-999)

A field experiment was conducted to assess N and NK split application to synchronize nutrient application with crop demand. Eight timings of application and different dose of N and NK both were taken as different treatments. Timings were planned to supply the fertilizer at different crop growth stages i e., at 10, 30, 45, 60 and 75 DAS. Split application of N and NK did not have any significant effect on plant height, monopodia plant⁻¹, sympodia plant⁻¹, boll plant⁻¹, boll weight and G.O.T. (Ginning Percentage). Bolls plant⁻¹ was affected significantly with the different mode of fertilizers application as well as timing of split application. The seed cotton yield did not deviate significantly due to split-cum-basal fertilizer application, however timings of split application of fertilizers resulted in significant changes in this productivity parameter. The extra net income from F₂ was only Rs. 2884 ha⁻¹ over F₁. Amongst the timing of split application, S₄ and S₅ having three splits up to 60 DAS proved significantly superior to some of the remaining treatments. Seed cotton yield ranged from 21.15 to 21.19 q ha⁻¹ with extra net income from Rs. 6109 to Rs. 6205 ha⁻¹ over S1. Other treatments except S₇ showed monetary loss from Rs. 900 to Rs. 2250 ha⁻¹. The treatment interactions were found to be significant GMR and NMR the characters under study.