Effect of phosphorus concentration on nutrient composition of soybean Glycine max L

Nutrient-elements are essential in human and animals’ diets. These nutrients are obtained from different sources such as food crops and sea-foods. Amongst these nutrients, phosphorus is one of the macro-nutrients that plays vital roles in growth and development of humans, animals and crops. Field experiment was conducted to evaluate the effect of phosphorus concentration in the nutritional composition of soybean. The experimental plots were harrowed, ploughed and the experimental design was laid out in a Randomized Complete Block Design (RCBD) followed by the planting of soybean seeds. The experimental designs such as: t0, t20, t40, and t60 were used to represent the following rates of phosphorus fertilizer application: 0kg/ha (control) 20kg/ha, 40kg/ha, and 60kg/ha respectively at one week-before-planting. The soybean (Glycine max L.) seeds were harvested at maturity (12weeks after planting), threshed and weighed. The seeds were taken to the laboratory for proximate and mineral analyses. The results showed that soybean treated with t60 (60kg/ha P) had the highest yield of 190.76kg/ha. Similarly, the result of proximate analysis showed that soybean treated with t60 (60kg/ha P) recorded the highest crude protein content of 39.51%. In addition, the data obtained from the mineral analysis showed that the Control, t0 (0kg/ha P) recorded significantly higher values for iron and calcium than others; while soybean treated with t20 (20kg/ha P) had the highest value for magnesium. Conclusively, application of phosphorus fertilizer at a rate of 60kg/ha was more promising for optimum seed-yield and better nutritional quality of soybeans. Therefore, this study recommends that soybean farmers should use phosphorus fertilizer at 60kg/ha.