Grain and fodder legumes as preceding crops affecting the yield and N economy of rice

Abstract

SUMMARY: Experiments made for 2 years on a sandy-loam soil showed that previous grain crops of mung bean (Vigna radiata), cow pea (V. unguiculata) and black gram (V. mungo) increased the grain and straw yield of a subsequent crop of rice relative to previous fodder crops of maize or guar bean (Cyamopsis tetragonoloba) or a grain crop of Phaseolus bean (Phaseohcs vulgaris). The benefits from preceding crops of mung bean, cow pea or black gram were equivalent to 36–67 kg N/ha of chemical fertilizer applied to the rice crop following a cereal. The legumes improved yield-contributing characters such as number of productive tillers/m², panicle length and number of grains/panicle. The yield increase from the preceding legumes was noted even when the rice crop was given increasing rates of fertilizer up to 90 kg N/ha.