Nitrogen partitioning and protein content of rajmash (Phaseolus vulgaris L.) as affected by inoculation and N-P application.

Effect of nitrogen, phosphorus and seed inoculation on nitrogen partitioning in different plant parts of rajmash and protein content in grain were examined under salt affected soil conditions. Both the parameters were influenced by inoculation and/or chemical N and P application. Patterns of N partitioning were found similar at different stages of plant growth but the values were relatively higher at maturity. Nitrogen content in leaf was found highest and that in root was the lowest. However, nitrogen content in pod was relatively higher than that in root, stem and leaf at maturity stage. Application of nitrogen and phosphorus alone or in combination were found effective to bring a change in nitrogen concentration in both inoculated and uninoculated plants. Efficacy of rhizobial strains also played vital role in changing nitrogen concentration in different parts of rajmash plant. 40 kg N ha⁻¹ + 120 kg P₂O₅ ha⁻¹ + seed inoculation with BR-885 strain of Rhizobium tropici was found the most suitable treatment combination and resulted significantly higher concentration of nitrogen (3.73 per cent)and grain protein (23.3%) in comparison to the other treatment combinations. However, 120 kg N ha⁻¹ + 120 kg P₂O₅ ha⁻¹ was found most effective amongst uninoculated treatments (20.0% grain protein).