Field experiments over two years were made to determine the effect of Sesbania aculeata/S rostrata green manuring and mungbean residue incorporation on the productivity and plant-N uptake of a rice-wheat cropping system. Green manuring of Sesbania or incorporation of mungbean residue resulted in recycling of 77-113 kg N ha(-1) and increased productivity of the rice-wheat cropping system by 0.5-1.3 t ha(-1) y(-1) and plant-N uptake by 12-35 kg ha(-1) y(-1) over no summer crop. The productivity and plant-N uptake of the rice-wheat cropping system, without nitrogen application to rice after Sesbania green manuring or incorporation of mungbean residue, were similar to those obtained with 120 kg N ha(-1) application to rice after no summer crop. Mungbean residue incorporation had the advantage of producing 0.5-1.3 t ha(-1) y(-1) of protein-rich pulse grain and was more useful for increasing the productivity of a rice-wheat cropping system.