Nitrogen and sulphur uptake and efficiency in mustard-moong-maize cropping s ystem

Two rotational field experiments with the cropping system of mustard (Brassica Juncea L), moong (green gram, Vigna aureus L.) and maize (Zea mays L.) were conducted in 1986-87 and 1987-88, using 15N and 35S to evalute the uptake and utilisation of applied N and S in the system. The application of both N and S showed a synergistic effect on dry matter yield and uptake of nitrogen and sulphur by the first crop mustard. The subsequent moong crop, although showed the beneficial effect of both N and S application on grain and dry matter yield but the actual uptake of residual fertiliser 15N and 35S was little. The mustard crop utilised fertiliser N to the extent of 53 to 69 per cent and fertiliser S, 20 to 39 per cent. The residual uptake of fertiliser N and S by succeeding mong and maize crops ranged from 1 to 3 per cent only. The sulphur application also increased the oil content in mustard seed by 2.8 per cent and oil yield by 10.6 per cent. (author). 13 refs., 8 tabs