N-Sparing Benefit of Clusterbean (Cyamopsis tetragonoloba) to Indian Mustard ( Brassica juncea) Under Semi-Arid Conditions of Northwestern India

N-Sparing Benefit of Clusterbean (Cyamopsis tetragonoloba) to Indian Mustard ( Brassica juncea) Under Semi-Arid Conditions of Northwestern India

For sustainable productivity, integrated nutrient management based on cropping system can plays an important role to meet the oil requirement of the growing population especially in developing countries like India. The inclusion of grain legumes in a cropping system has great potential in N saving and in the development of sustainable agriculture. A three year field experiments were carried out to investigate the nitrogen requirement of Indian mustard ( Brassica juncea ) following grain legume clusterbean (Cyamopsis tetragonoloba) to realize the residual benefits. After the harvest of clusterbean, four levels of N i.e. 0, 33, 66 and 100 kg N ha-1 were tested in Indian mustard. The grain yield of Indian mustard sown after clusterbean increased significantly only up to 66 kg N ha-1 and further increase in N to 100 kg ha-1 resulted in marginal decline in grain yield during all the three years of experimentation. The uptake of N, P and K in grain increased significantly only up to 66 kg N ha-1, however, in straw N, P and K uptake increased significantly up to 100 kg N ha-1 during all the three years. Agronomic efficiency of N, apparent N recovery and physiological efficiency decreased with increased level of N. These results suggest that integration of grain clusterbean in cropping sequence can save 33 kg N ha-1 in raising subsequent Indian mustard crop without any extra cost...