EFFECTS OF PHUSPHORUS FERTILIZER ON GROETH AND YIELD PARAMETERS IN THREE 3 (VIGNA UNGUICULATA L.) VARITIES IN SUDANN SAVANN

Abstract This study examined the effects of phosphorus fertilizer on the growth and yield parameters of three cowpea (Vigna unguiculata L.) varieties in the Sudan Savanna ecological zone. The experiment was conducted to evaluate the response of different cowpea varieties to phosphorus application and to identify the variety with the best growth and yield performance under the prevailing environmental conditions. A field experiment was laid out using a suitable experimental design with different phosphorus fertilizer levels applied to three selected cowpea varieties. Data were collected on growth parameters such as plant height, number of leaves, and number of branches, as well as yield parameters including number of pods per plant, pod length, seeds per pod, 100-seed weight, and grain yield. The results showed that phosphorus fertilizer significantly improved both growth and yield characteristics of cowpea compared to the control treatment. Increased phosphorus application enhanced plant vigor, flowering, pod formation, and grain production. Significant differences were also observed among the varieties, indicating variations in their response to phosphorus fertilization. One of the varieties consistently recorded superior growth and yield performance, suggesting better adaptation to the Sudan Savanna environment. The interaction between phosphorus levels and cowpea varieties further influenced several growth and yield parameters. The study concluded that phosphorus fertilization plays a vital role in improving cowpea productivity in the Sudan Savanna. Therefore, the application of an appropriate phosphorus fertilizer rate, together with the cultivation of high-performing cowpea varieties, is recommended to enhance cowpea yield and contribute to food security and farmers' income in the region.