Effect of residue and nitrogen management on wheat productivity and economics under south Bihar alluvial conditions

Abstract

A field experiment was conducted during the rabi season of 2024-25 at the research farm of Bihar Agricultural University, Sabour, Bhagalpur, Bihar, to evaluate the effect of crop residue and nitrogen management on the productivity and economics of wheat variety 'DBW 187' (Karan Vandana). The experiment comprised seven treatments- 100% RDN through chemical fertilizers, 50% RDN, 75% RDN, 50% RDN + 30% rice residue incorporation, 75% RDN + 30% residue, 75% RDN + 30% residue + Pusa decomposer @ 4 capsules ha⁻¹ and Control, laid out in a Randomized Complete Block Design (RCBD) with three replications. Results showed that the highest grain yield (4.70 t ha⁻¹) and net returns (₹88,492/ha) were recorded under 100% RDN through chemical fertilizer, followed closely by the treatment 75% RDN plus 30% rice residue + Pusa decomposer @ 4 capsules ha-1 (4.64 t ha⁻¹ and ₹86,694/ha), with a marginal yield difference of only 1.29%. Straw yield, harvest index, and benefit-cost ratio were also statistically similar between these two treatments. The incorporation of Pusa decomposer @4 capsules ha⁻¹ in 75% RDN plus 30% rice residue enhanced residue breakdown, and nutrient availability thereby improving productivity and profitability. This dose is a viable and eco-friendly alternative to full chemical fertilization, supporting sustainable wheat production in the South Bihar Alluvial Plain zone.