Abstract

Plant growth promoting rhizobacterial isolates from the rhizosphere of two arid weed plants, Prosopis juliflora and Parthenium hysterophorus were evaluated for their multifunctional beneficial activities in aerobic rice under field condition. Four elite strains showing multifaceted beneficial activities including nitrogen fixation, mineral solubilization, phytohormone production with antagonistic activity against soil pathogens were inoculated to aerobic rice (cultivar PMK3) and compared with standard Azophos bioinoculant technology. The results of the field experiment revealed that the strain, PARZ11 from Parthenium hysterophorus, phylogenetically authenticated as Azospirillum sp., increased the plant growth and yield of aerobic rice compared to other isolates. The grain yield increase due to PARZ11 was on par with standard Azophos inoculant application and inoculating this strain enhanced the total bacterial-and diazotrophic counts in the rhizosphere of rice. The present study clearly demonstrated the ability of PGPR isolate PARZ11 as a suitable bioinoculant for aerobic rice. The added advantage of using this isolate was tolerance to abiotic stresses such as drought and salt.

Keywords: PGPR, rhizobacteria, aerobic rice.