Characterization of plant growth-promoting rhizobacteria isolated from chilli rhizosphere of Southern Plateau and hills region

Abstract

Plant Growth Promoting Rhizobacteria (PGPR) is a community of bacteria located in the rhizosphere of plant which are can suppress directly or indirectly plant diseases caused by different plant pathogens and also promote plant growth. Twenty three rhizospheric soil samples of chilli plants from Southern Plateau and Hills region agro-climatic zones of Karnataka and Andhra Pradesh states of India were collected and isolated on four different types of media viz. TSA (Tryptone soya agar), NA (Nutrient Agar), CPG (Casamino peptone glucose) and Kings’ B media in the present study. A total of thirty one bacterial isolates were isolated and screened their antagonistic against Ralastonia solanacearum UTT- 25 and plant growth promoting activities in vitro condition. Out of 31 isolates of rhizobacteria, 35.4 % rhizobacteria showed antagonistic ability to inhibit growth of R. solanacearum. In vitro screening of PGP activities rhizobacteria showed phosphate solubilization (64.2%), production of IAA (78.5%), production of ammonia (78.5%), production of HCN (35.7%), and siderophore production (50%). The rhizobacterial isolates showing plant growth promoting activities along with having biocontrol potentials were characterized using morphological, biochemical and physiological. These rhizobacteria are good potential to use as biopesticide and biofertilizers for improving crop health and growth.