Phosphorus is critical to cowpea yield because it stimulates growth, initiate nodules formation as well as influencing the efficiency of rhizobium-Legume symbiosis. In Nigeria, legumes receive little form of mineral phosphorus fertilizer as they accordingly depend on the natural soil available phosphorus for growth and yield which results to low yield. It was due to this problem that field trials were conducted at the Research Field of Horticultural section of Samaru College of Agriculture, Ahmadu Bello University, Zaria, Nigeria during 2015 and 2016 wet seasons to investigate the effect of phosphorus levels on the growth and yield of cowpea (SAMPEA 17). The treatments consisted of five levels of phosphorus (0, 10, 19, 29 and 39 kgPha-1) in the form of single superphosphate laid out in randomized complete block design (RCBD) and replicated four times. The results showed that application of 39 kgPha-1 resulted to highest growth in terms of plant height, number of branches per plant, leaf area index and yield. This rate is therefore recommended for enhancing growth and yield of the cowpea.
Keywords: Cowpea, Phosphorus, Growth, Yield