Effects of Phosphorus Fertilizer Rate and Rhizobia Inoculation on Growth, Nodulation and Yield of Soybean [Glycine max (L.) Merrill] Varieties under Nitisols of Southwestern Ethiopia

Abstract

Soybean is high quality protein source for resource poor families and oil crop in Ethiopia, but low phosphorus levels and soil acidity limit yields in the Buno Bedele area. Therefore, the aim of this study is to investigate the effect of phosphorus fertilizer and different rhizobia strains on soybean performance in terms of growth, nodulation, and yield in Nitisol of southwestern Ethiopia. The experiment was conducted at Buno Bedele, Ilke kerero sub site of Bedele Agricultural Research Center in 2023 main cropping season. The experiment included 16 treatment combinations four phosphorus levels (0, 10, 20 and 30 kg P ha -1 ), with and without inoculation MAR-1495 rhizobia, and two soybean varieties (Ketta and Cheri). The experimental design was Randomized Complete Block Design RCBD) in factorial arrangement with three replications. The Analysis of variance showed Very high significant (P<0.0001) interactions between rhizobia inoculation and phosphor us levels, as well as variety (P<0.0001) effects on growth, nodulation, and yield