Plant growth promoting and antagonistic activity of consortia of halotolerant Bacillus and Rhizobium spp

Salinity prevents plants from taking up water and exposing them to draught stress, to overcome this, studies have shown that halotolerant organism can be effective in plant growth promotion in saline condition. Studies have also shown that consortium strains are more effective in plant growth promotion and bio control activity. In the present study, from various soil samples total 11 isolates were obtained. Morphological and biochemical analysis confirmed that 8 were Rhizobium and 3 were Bacillus spp.
Halotolerant analysis confirmed that 3 isolates could tolerate salt concentration up to 6%, hence these three were used for further studies. The isolates were screened for plant growth promotion assays; it includes Indole acetic acid production, Phosphate Solubilization and Zinc Solubilization. The isolates were also screened for lytic enzymes production like (Chitinase, Protease and Cellulase).
In pot assay, plant growth promotion for leguminous (Methi plant) and non- leguminous (rice plant), with single and consortium strains under halotolerant condition were done, the result showed subsequent increase in growth of shoot length and root length. Application of mixture of strains resulted with notable increase in plant growth compared to the individual strain. In pot assay, in bio-control activity consortium organism were found to inhibit plant pathogens and hence can be used as bio-control agents. Thus from the above study it can be concluded that  the use of consortium organisms in field application can be used as biocontrol and bio-fe rtilizer agents.