Effect of nutrients omission on yield, nutrient uptake and economics of rabi sorghum in vertisols under rainfed and irrigated conditions

Abstract

A field experiment was conducted to study the “Effect of nutrient omission on yield, nutrient uptake and economics of rabi sorghum in vertisols under rainfed and irrigated conditions” at AICRP on sorghum, MARS, University of Agricultural Sciences, Dharwad, during rabi 2020. The experiment consisted of two main plots (M₁: Rainfed and M₂: Irrigated) and nine nutrient omission treatments. The experiment was laid out in a split plot design with three replications. The results indicated that, significantly higher grain yield (44.87 q ha^-1), stover yield (8.52 t ha^-1), total nutrient uptake (93.86 kg N ha^-1, 28.51 kgP₂O₅ ha^-1 , 94.04 kg K₂O ha^-1, and 226.24 g Zn ha^-1) , higher gross returns ( ₹ 115786), net returns (₹ 77085) and BC ratio (2.99) were recorded under irrigated condition (M₂). Among nutrient omission treatments, application of 50:25 kg NP ha^-1 + FYM @ 3 t ha^-1 + ZnSO₄ @ 15 kg ha^-1 (S₁) exhibited  significantly higher grain yield (49.56 q ha^-1) , stover yield (9.55 t ha^-1), total nutrient uptake (109.97 kg N ha^-1, 32.63 kg P₂O₅ ha^-1, 109.33 kg K₂O ha^-1 and 283.63 g Zn ha^-1) and higher gross returns (₹ 128146) .While, application of 50:25 kg NP ha^-1+ ZnSO₄ @ 15 kg ha^-1 (S₂) recorded significantly higher net returns (₹ 88057) and BC ratio (3.41). The per cent reduction in grain and stover yield was to the tune of 31.88 and 34.86 respectively due omission of both nitrogen and phosphorous