Effect of irrigation, residue and nutrient management on growth, yield and nutrient uptake by soybean under soybean-wheat cropping system in south-eastern Rajasthan

A field experiment was conducted at Agricultural Research Station, Kota during rainy (Kharif) seasons of 2016 to 2018 to study the effect of irrigation, residue and nutrient management on growth, yield and nutrient uptake by soybean under soybean-wheat cropping system of south-eastern Rajasthan. The treatments of experiment consisted of 24 factorial combinations of two irrigation schedules viz., irrigation at flowering stage and irrigation at flowering and pod development stages in main plots, four residue management practices viz., sowing of soybean after wheat residue burning, wheat residue incorporation without irrigation, residue incorporation with irrigation and application of urea @ 25 kg/ha, and residue incorporation with irrigation and application of urea @ 25 kg/ha + cellulolytic microbes @ 2.0 kg/ha in sub plots and three nutrient management practices viz., 75% recommended dose of fertilizers (RDF), 100% RDF and 125% RDF in sub-sub plot was laid out in split plot design with 3 replications. Pooled data revealed that irrigation applied at flowering and pod development stages in soybean recorded significantly higher values of dry matter production (g/m2) at 60, 75 DAS and at harvest and crop growth rate and relative growth rate during 60–75 days and 75-harvest over irrigation applied at flowering stage. Similarly, same trends were observed in branches/plant, pods/plant, seeds/pod, seed index, seed and straw yield, net return and profitability, N, P, K & S uptake by seed, straw and total uptake by soybean. Residue + irrigation + urea @ 25 kg/ha + cellulolytic microbes @ 2.0 kg/ha resulted in significant enhanced growth and yield attributes, seed and straw yield, net return and profitability, nutrient uptake over residue burning. Application of 125% RDF recorded maximum growth and yield attributes, seed (1.51 t/ha) and straw (2.17 t/ha) yield, net return (f 2,5700/ha) and profitability (273/ha/day) and nutrients uptake by soybean.