Characterization of functionality traits of plant growth promoting rhizobacteria antagonistic to Fusarium oxysporum f. sp. ciceris

Forty-two rhizobacterial isolates were isolated from chickpea rhizosphere soils collected from twelve different locations of the Punjab. The isolates were characterized biochemically and found belonging to genera Pseudomonas (19), Bacillus (22) and Serratia (1). Three of the isolates i.e. Ps-17, Ps-14 and S-10 exhibited antagonistic effect on growth of Fusarium oxysporum f. sp. ciceris under in vitro conditions, the growth inhibition ranged from 28.6–42.8 per cent, maximum recorded with Ps-17. In liquid culture, maximum inhibition of mycelial proliferation was 82.9% (Ps-17) followed by 49.5% (Ps-14) and 40.2% (S-10). Fungal growth inhibition due to production of volatile metabolites was exhibited by Ps-17 (13.8%) and Ps-14 (9.2%). Seven of the isolates produced siderophores as evidenced on chrome-azurol S agar, maximum being produced by Ps-17 (114 μg/ml). Isolates Ps-17 and Ps-14 also produced secondary metabolites HCN and ammonia which implicated in antagonistic activity.