Conjoint use of Rhizobium and PGPR in mung bean boosted soil health and productivity of succeeding wheat

Biofertilizer use is gaining momentum in crop production, being a renewable and cost-effective source of plant nutrients. This study assessed the response of mung bean (Vigna radiata L.) to seed inoculation with Rhizobium sp. and plant growth promoting rhizobacteria (PGPR), alone and in combination, and their residual effect on the productivity of succeeding wheat (Triticum aestivum L.) and on soil health. Seed inoculation with Rhizobium alone and with PGPR in mung bean significantly increased root nodulation. Conjoint use of Rhizobium sp. and plant growth promoting rhizobacteria (PGPR) resulted in a significantly higher grain yield (10.0%), available N (18.6%), P (58.1%) and K (20.4%) in soil after harvesting than the uninoculated control. Irrespective of N levels, this treatment also produced a 10.2 and 9.7% increase in grain and straw yields of succeeding wheat than those obtained with preceding uninoculated mung bean. Dual inoculation with Rhizobium sp. and PGPR in mung bean also resulted in a significantly more available N and P in soil (15.4 and 30.2% at 45 days after sowing and 14.5 and 60.3% at 75 days, respectively). Biofertilizer application in preceding mung bean also showed a significant improvement in soil biological activities during succeeding wheat crop growth.