Performance of cluster bean (Cyamopsis tetragonoloba) as influenced by nitrogen and phosphorus fertilization and biofertilizers in Western Rajasthan.

A field experiment was conducted to assess the effect of Rhizobium and phosphorus solubilizing bacteria (PSB) alone and in combination with different recommended NP levels i.e. RDF (20–17.4 kg N-P/ha) on performance of rain fed cluster bean (Cyamposis tetragonoloba L. Taub.) at Bikaner. Increasing NP levels resulted in significant increase in growth, yield attributes, and yield. The increase in seed yield was significant up to 50% RDF in 2004 (1.01 t/ha) and up to 75% RDF in 2005 (1.15 t/ha). However biological yield (mean 4.66 t/ha) increased significantly upto 75% RDF during both the years. Unfertilized control recorded the least seed and biomass yields. However, P uptake increased significantly up to application of 100% RDF N, K uptake and B:C ratio increased only up to 75% RDF. The highest net returns (Rs 22,393/ha) were recorded with 100% RDF. The growth, yield attributes, and yield increased significantly due to inoculation of cluster bean with biofertlizers. Combined inoculation of Rhizobium and PSB was more promising from productivity and profitability point of view as compared to their sole inoculation. Integrated use of 75% RDF with Rhizobium + PSB inoculation was the best for cluster bean.