Efficacy of bioinoculants to control of bacterial and fungal diseases of rice (Oryza sativa L.) in northwestern Himalaya.

Abstract

Biological control holds great promise for environmentally friendly and sustainable management of the phytopathogens. The multi-function features of plant growth-promoting rhizobacteria (PGPR) enable to protect the plants from disease infections by replacing the chemical inputs. The interaction between the plant root exudates and the microbes stimulates the production of secondary metabolism and enzymes and induces systemic resistance in the plants. The aim was to identify the potential PGPR which would show an antagonistic effect against basmati rice fungal and bacterial diseases. In the study, native originating microbes have been isolated, characterized using 16S rRNA sequencing, and used as potential antagonistic microbial isolates against diseases of rice plants. Rhizobacteria isolated from rhizosphere, endo-rhizosphere, and bulk soil samples of Basmati 370 exhibited promising inhibitory activity against rice pathogens. Molecular characterization of bacterial isolates based on 16S rRNA sequencing classified the bacterial isolates into different genera such as Bacillus, Pseudomonas, Streptomyces, Exiguobacterium, Aeromonas, Chryseobacterium, Enterobacter, and Stenotrophomonas. PGPRs exhibited biocontrol activities against various rice diseases like bacterial leaf blight, leaf blast, brown spot, and sheath blight and boost the plant growth traits. In the study, the potentially identified PGPRs isolates could be used as efficient bioinoculants as bio-fertilizers and biocontrol agents for sustainable rice crop production.