Residual effect of integrated nutrient management on the growth, yield and profitability of linseed in black gram -linseed cropping system of plateau region of Jharkhand

A field experiment was conducted during Kharif 2020–21, 2021–22 and Rabi 2020–21, 2021–22 on sandy loam soil at Agronomy Research Farm, Birsa Agricultural University, Kanke, Ranchi, Jharkhand to study the residual effect of integrated nutrient management imposed to preceding black gram on growth, yield and economics of linseed in black gram–linseed cropping system. The experiment was laid out in factorial randomized block design with four fertilizer levels (control, 75% RDF, 100% RDF and 125% RDF), two FYM levels (without and FYM @5 t ha⁻¹) and three biofertilizer levels (Rhizobium, PGPR, Rhizobium + PGPR), replicated thrice. Linseed crop received only 50% RDF. Results showed maximum plant height of black gram and linseed with 125% RDF, statistically at par with 100% RDF. Application of FYM @5 t ha⁻¹ to preceding black gram significantly enhanced plant height, dry matter, CGR and yield attributes of succeeding linseed in both years. Dual seed inoculation with Rhizobium + PGPR to preceding black gram recorded higher growth and yield of linseed compared to sole inoculation. Maximum seed and stover yields of linseed (1090 & 2158 kg ha⁻¹ and 1107 & 2183 kg ha⁻¹) were obtained with 125% RDF to black gram, followed by 100% RDF. FYM @5 t ha⁻¹ also produced significantly higher yields (1028 & 2061 and 1038 & 2076 kg ha⁻¹). The highest gross return (₹46331–48119 ha⁻¹), net return (₹26902–28690 ha⁻¹) and B:C ratio (1.38–1.48) were recorded with 125% RDF, at par with 100% RDF, while FYM and Rhizobium + PGPR further improved profitability.