Interaction response of Rhizobium and phosphorus on dinitrogen fixation and N-P uptake by French bean (Phaseolus vulgaris L.) under sodic soil conditions

A field experiment was conducted in partially reclaimed salt affected soil of eastern Uttar Pradesh to examine the effect of phosphorus (0, 50, 100 and 150 Kg ha⁻¹) and seed inoculation with Rhizobium phaseoli and Rhizobium tropici on active N₂-Fixation, N-P uptake and green pod yield of French bean. Both species of Rhizobium were found effective for biological nitrogen fixation in symbiosis with French bean plants. Extant of biological nitrogen fixation depended on efficacy of strains. Tal-1701 strain of Rhizobium phaseoli fixed 61.71 Kg N ha⁻¹, however, BR-885 and BR-865 strains of Rhizobium tropici fixed 61.17 and 56.65 Kg N ha⁻¹respectively. Non-inoculated plants did not fix dinitrogen. Amongst various levels of phosphorus, 100 KgP₂O₅ha⁻¹ wasfound tobethemostsuitable andyielded thehighest amountoffixednitrogen (77.21Kg ha⁻¹), N-P uptake (65.2 and 5.7 Kg ha⁻¹ respectively) and green pod (3.45 t ha⁻¹) of French bean in combination with Rhizo bium phaseoli.