Residual influence of sweet sorghum genotypes and nitrogen levels on performance of succeeding wheat in sweet sorghum-wheat cropping system

A field experiment was conducted during winter 2009-10 at research farm of Division of Agronomy, Indian Agricultural Research Institute, New Delhi to study the effects of nitrogen levels applied to sweet sorghum genotypes on performance of succeeding wheat. The experiment was conducted under split-plot design with three replications. Four levels of residual nitrogen (0, 50, 100 and 150 kg N ha–1) were assigned to the main plots and three sweet sorghum genotypes to the sub-plots. Wheat was sown in preceding plots of nitrogen applied to sweet sorghum genotypes. Result showed that growth, yield and yield attributing parameters, NPK uptake and quality of wheat enhanced significantly with application of nitrogen to preceding sweet sorghum crop up to 150 kg N ha-1. The highest values of plant height, yield attributes viz. effective tillers per meter row length, spike length, number of spikelet per spike, number of grains per spikelet, grain yield, biological yield, protein content and protein yield, sedimentation value, hectoliter weight, gluten content, gross returns, net returns and net B: C ratio of wheat were obtained with the application of 150 kg N ha-1 to preceding sweet sorghum in both seasons. Effect of preceding sweet sorghum genotypes on growth, yield and yield attributes, quality parameters and economics of succeeding wheat was not significant in both seasons. It is concluded that application of 100 to 150 kg N ha-1 to preceding sweet sorghum crop had residual effect on the performance of succeeding wheat in sweet sorghum-wheat cropping system.