Influence of phosphorus and biofertilizers on the productivity and profitability of summer black gram (Phaseolus mungo) under sub-tropical conditions of Nagaland

To study the influence of phosphorus and bio-fertilizers on the productivity and profitability of summer black gram under the sub-tropical conditions of Nagaland a field experiment was conducted at the experimental farm of School of Agricultural Sciences (SAS), Nagaland University during the summer season of 2022. The experiment was conducted by taking 2 factors i.e. phosphorus levels, viz control, 15 kg P/ha, 30 kg P/ha and 45 kg P/ha along with bio-fertilizers i,e (control), Rhizobium (20 g/kg seed), Phosphate solubilizing bacteria (20 g/kg seed) and Rhizobium (20 g/kg seed) + Phosphate solubilizing bacteria (20 g/kg seed) in factorial randomized block design which were replicated thrice. The black gram variety “Pusa 1” was uniformly fertilized by 20 kg N/ha through Urea. The experimental study revealed that among the phosphorus levels, the application of 45 kg P/ha recorded significantly highest yield attributes and seed yield (724.17 kg/ha). However, among bio-fertilizers, application of Rhizobium (20 g/kg seed) + Phosphate solubilizing bacteria (20 g/kg seed) resulted in highest yield attributes and yield of black gram. Among the economic analysis, application of 45 kg/ha phosphorus and combine treatment of Rhizobium + Phosphate solubilizing bacteria incurred the highest cost of cultivation, highest gross return, net return and Benefit cost ratio. Therefore, for summer black gram cultivation, application of 45 kg/ha phosphorus and treatment of Rhizobium + Phosphate solubilizing bacteria was proved to be profitable.