Microbial inoculation of Rhizobium and phosphate-solubilizing bacteria along with inorganic fertilizers for sustainable yield of soybean [Glycine max (L.) Merrill]

ABSTRACT

A field experiment was conducted to assess the effect of microbial inoculants and inorganic fertilizers for sustaining the yield of soybean. Application of 100% recommended dose of fertilizer (RDF) gave significantly highest yield (2433 kg ha⁻¹) over 75% RDF (2317 kg ha⁻¹) and without RDF (2205 kg ha⁻¹). Seeds inoculated with Rhizobium (Bradyrhizobium japonicum) and phosphate-solubilizing bacteria (2480 kg ha⁻¹) gave significantly highest soybean yield over without inoculation (2191 kg ha⁻¹). Rhizobium and phosphate-solubilizing bacteria with 100% RDF (2674 kg ha⁻¹) gave significantly highest seed yield than rest of the treatment combinations. Root nodules and their dry weight were remained un-influenced due to fertilizer levels, whereas in bio-fertilizers, it was significantly higher with Rhizobium inoculation (24.3 and 408 mg, respectively) followed by dual inoculation of Rhizobium and PSB. 100% RDF and dual inoculation with Rhizobium and PSB earned Rs. 47916/- and Rs. 51182/- net returns per ha, respectively.

KEYWORDS:

• Bradyrhizobium japonicum
• dual inoculation
• inorganic fertilizers
• nitrogen fixation
• phosphate-solubilizing bacteria

Acknowledgments

The authors are grateful to ICAR-Indian Institute of Soybean Research, Indore, M.P. (India) and Director, Agharkar Reaserch Institute, Pune, Maharshtra (India) for providing facilities.