Growth promoting properties of Mycobacterium and Bacillus on rice plants under induced drought

Management of drought stress through application of plant growth promoting rhizobacteria (PGPR) is now considered as an effective strategy in the present scenario of altered environmental conditions of the world. The aims and objectives of the present investigation was isolation, characterization and identification of some potential microbial resources (PGPR) from drought-affected upland rice fields of South Bengal followed by experimentation on the effect of isolated PGPR on drought induced rice seedlings. Selected isolates were isolated from rice field rhizospheric soils and tested for their PGPR activity, through phosphate solubilization, nitrogen fixation, IAA production and ACC deaminase activity. Then, the selected isolates were identified through 16S rDNA sequencing and phylogenetic analysis. Among the screened isolates two (isolate 1 and isolate 6) showing plant growth promoting traits, was applied on studied germplasm (IR64) to find out the influence of the applied organisms on rice growth and development under induced drought. Both organisms showed a positive influence (through increase in germination percentage, root growth, shoot growth, fresh weight and dry weight) on the studied rice growth and development under induced drought. Isolate 1 and 6 identified as species of Mycobacterium sp and Bacillus sp respectively through molecular taxonomy. Hence, these two isolates are expected to alleviate drought stress in the rice field for their nature of plant growth promotion under drought stress.