Effects of Inorganic Fertilizers on Soybean (Glycine max (L) Merr) Varieties in Ogbomoso, South West, Nigeria

Abstract

Crops response to nutrients effect in terms of growth and yield; soybean is not an exception to the major nutrients. Hence, a pot experiment was conducted in Ogbomoso, Oyo State, Nigeria to determine the response of ten soybean varieties to NPK fertilizers.The treatments are: NPK application; (NAF-No fertilizer application), (P+K-Phosphorus and potassium), (P+N Phosphorus and Nitrogen), (P; phosphorus alone) and (N+P+Kapplication). It was a factorial experiment, laid in Completely Randomized Design with four replicates. Data collected are: plant height and number of leaves, flowers and pods, weights of; fresh and dry biomass, root and dry matter, and nutrient uptake. Data were subjected to Analysis of Variance and treatment means were separated using (DMRT ? ).In conclusion, the interactions between the two factors 0.05 were highly significant onthe growth parameters and nutrient uptakes. The interactive effects on soybean varietyTGm1057 under NFAproduced the highest fresh shoot and rootweights, while under (P+K) application, TGm1052 had the highest fresh root weight.Variety TGm1057 under NFA has the highest N uptake while variety TGm1052 under (P+K)application had the highest P uptake. But TGm1057 under (P+N) applicationhad the highest N and K uptake. The highest soybean pod yield was obtained from variety TGm1052 under phosphorus and potassium (P+K) application while TGm1057 had the least yield under the same fertilizer application. In conclusion, it can be recommended that soybean variety TGm1057 be cultivated with little or no N fertilizer but with phosphorus and potassium fertilizer application for optimal pod yield.