Potential biocontrol and superlative plant growth promoting activity of indigenous Bacillus mojavensis PB-35(R11) of soybean (Glycine max) rhizosphere

Abstract

Disease control using microbes that exhibit beneficial effects on plants to strengthen the host is a foremost requirement in agriculture. The aim of the present study is to search for an effective biocontrol agent against Rhizoctonia solani endowed with high plant growth potential. A total of 95 bacterial strains were isolated from the soybean plant rhizosphere and screened in vitro against R. solani by dual culture technique, revealing that strain PB-35(R11) was the most efficient for controlling R. solani with 54.835% inhibition. Isolate PB-35 was identified by 16S ribosomal RNA (rRNA) gene sequencing as Bacillus mojavensis. It was observed that, in order to effectively control R. solani in vitro, B. mojavensis produced volatile metabolites. Fourier-transform infrared (FTIR) analysis revealed the presence of aldehyde (CHO) group (1739.79 cm−1), acetyl group (1896.03 cm−1), and cyanide group (2360.87 cm−1) in the crude extract of isolate PB-35(R11). Furthermore, the siderophore, indole acetic acid (IAA), catalase, oxidase, and chitinase production ability as well as phosphate solubilization potential of PB-35(R11) make it beneficial for crop growth and soil biofortification.