Response of N-fixing and P solubilizing bacteria with reduced dose of fertilizers on productivity of soybean (Glycine max L.)

Abstract

A field experiment was conducted during the 2022-23 cropping season at the Research Farm, College of Agriculture, IGKV, Raipur, to evaluate the effect of nitrogen-fixing and phosphorus-solubilizing bacteria in combination with reduced fertilizer doses on the productivity of soybean (Glycine max L., var. CG SOYA 11-15). The study employed a Randomized Block Design with 9 treatments and 3 replications. Results showed that microbial inoculation significantly improved plant height, nodulation, leghaemoglobin content, chlorophyll content, grain yield, and nutrient use efficiency. The treatment T5 (75% N + 100% P & K + Bradyrhizobium daqingense) recorded the highest grain yield (20.9 q ha⁻¹), maximum nodules (66 plant⁻¹), and highest leghaemoglobin (1.87 mg g⁻¹ FW), achieving 25.5% N savings. Treatment T7 (Bacillus aryabhattai) saved 21.6% P with high yield (20.1 q ha⁻¹), while combined inoculations in T8 and T9 saved over 20% N and P. These findings suggest that integrating microbial inoculants with reduced fertilizer inputs enhances soybean productivity and sustainability.