摘要 : The effects on four cowpea varieties of four levels and two sources of phosphorus are described. Crop growth and yield increased significantly with increasing levels. Application of 37 kg P_2 O_5/ha gave 54% higher seed yield than... 展开 The effects on four cowpea varieties of four levels and two sources of phosphorus are described. Crop growth and yield increased significantly with increasing levels. Application of 37 kg P_2 O_5/ha gave 54% higher seed yield than the control but no significant yield advantages were obtained with higher levels. The interactions of phosphorus concentration and variety influenced grain yield significantly; interaction of phosphorus source and variety significantly influenced grain yield, onset of flowering, number of flowers, pods, pod weight and seeds per plant. Grain yield was significantly and positively correlated with yield components and with growth characters. 收起