Studies on Rhizosphere-Bacteria mediated Biotic and Abiotic stress tolerance in Chickpea (Cicer arietinumL.)

Abstract

Rhizospheric bacteria promote plant health and combat with pathogenic microorganisms. Available reports indicate the activity of PGPR are in protection of plant under abiotic stresses. In the present work we have compared the growth promotion and biochemical responses of plants influenced bybacteria isolated from the rhizosphere of different plants. Two Pseudomonas strains S1 (P. putida) and Cgr (P. aeruginosa) were isolated from chickpea and congress grass, respectively, and their antimicrobial activity was tested against Sclerotinia sclerotiorum. Both strains are tested for HCN, IAA and ammonia production. Their surviving ability in salt stress was evaluated and compatibility test was performed. We have got some interesting results that plant defense enzymes and phenolic substances were accumulated in higher concentrations in plants that were treated with the two bacterial strains (Cgr and S1) either individually or in combination when challenged with biotic (Sclerotinia sclerotiorum) and abiotic stress (NaCl salt stress) compared to the non-bacterized plants but exposed to biotic as well as abiotic stresses. These results indicates that the Cgr and S1 have potential to be used as biocontrol agents that can help chickpea to combat attack of S. sclerotiorum as well as thrive under salt stress. Moreover, the results also indicated a common pattern of defense response by chickpea against both the biotic and abiotic stress when they are bacterized by the two bacterial strains.