Effects of Rhizobium inoculation and Supplementation with P and K, on Growth, Leaf chlorophyll content and Nitrogen Fixation of Bush bean varieties

Abstract

Low crop productivity is a general problem facing most farming systems in sub-Saharan Africa (SSA). These low yields are pronounced in grain legumes and are often associated with declining soil fertility and reduced N2-fixation due to biological and environmental factors. Biological nitrogen fixation (BNF), a key source of N for farmers using little fertilizer, constitutes one of the potential solutions and plays a key role in sustainable grain legumes production. Phosphorus is needed in relatively large amounts by legumes for growth and has been reported to promote legumes growth and yield, nodule number and nodule mass in different legumes. Potassium influences the water economy and crop growth through its effects on water uptake, root growth, maintenance of turgor, transpiration and stomatal regulation. Various Studies have shown that Rhizobium inoculation, phosphorus and potassium has the potential to improve legumes growth, seed yield, nitrogen fixation and also nutrient up take of legumes. The potential role of rhizobia inoculants and supplementation of P an K with respect to growth, nitrogen fixation, nutrient uptake, total leaf chlorophyll content, and grain yield of legumes are given attention in this review.