Influence of integrated nutrient management on seed cotton yield, nutrient use efficiency and economics of Bt cotton (Gossypium hirsutum L.)

A field experiment entitled “Influence of Integrated Nutrient Management on Seed Cotton Yield, Uptake of NPK and Economics of Bt Cotton (Gossypium hirsutum L.)” was conducted during three consecutive Kharif seasons of 2017-18, 2018-19 and 2019-20 at experimental farm, Regional Agricultural Research Station, Lam, Guntur. to evaluate the influence of different nitrogen (N) management strategies on the growth and yield attributes of cotton. The experiment comprised seven treatments including a control (no nitrogen), full and partial recommended doses of nitrogen (RDN), and various methods of fertilizer application such as banding, spot placement, split doses, foliar urea sprays, and incorporation of green manure through sunnhemp intercropping. The pooled analysis of the three years experimental results showed that the maximum seed cotton yield of Bt cotton was recorded with application of 75% RDN (Placement as spot application in 4 splits- Basal, Squaring, Flowering & boll development) + Foliar application of 1% urea (Squaring, Flowering & boll development) + Raising of sunhemp and incorporation before flowering (T7). Similarly, the growth and yield attributes viz., plant height, total number of sympodial branches per plant, total number of bolls per m2 at harvest and uptake of NPK and economics of cotton crop were recorded significantly higher under this treatment.