EFFECTS OF PHOSPHORUS DEFICIENCY ON PHENOLOGY AND YIELD COMPONENTS OF SHORT-DURATION PIGEONPEA

In pot experiments with Alfisols (fine hypothermic Udic Rhodustalf) of low P status, P deficiency delayed flowering and maturity of pigeonpea (Cajanus cajan (L.) Millsp.) cultivar ICPL 6 by up to two months. A reduction in grain yield due to P deficiency could primarily be attributed to less biomass, less branching, fewer pods plant-1 and reduced seed mass. At the soil P level giving near-minimum grain yields, concentrations were about 0.3% in the seed and 0.15% in the leaves at plant maturity. These results have implications for adapting short-duration pigeonpea to various cropping systems.