Screening of rhizobacteria against Fusarium oxysporum f. sp melongenae, the causal agent of wilt disease of eggplant

Rhizosphere isolates of Bacillus and Pseudomonas species isolated from the roots of eggplants (Solanum melongena L.) were collected in eggplant cultivated areas in various geographical districts of Turkey. Isolates were evaluated for siderophore, protease and cyanide production along with the cell wall degrading enzyme production as well as phosphate solubilizing and nitrogen fixing capacities. The isolates showing good performance were tested against Fusarium oxysporum f. sp. melongenae, a highly destructive fungal agent for eggplants, for the antagonistic activities. The isolates designated as 11-4, 13-1, 56K-3, 65A-3, 67A-2, 76A-1, 85A-2, 10a, 318b, 346a, 379c, 007-1, 007-4, and 048-2 were found promising in inhibition of F. oxysporum f. sp. melongenae in vitro conditions. The isolates differing in their antagonistic responses to F. oxysporum f. sp. melongenae would be identified in species level. Also, the best performing isolates for the reduction of disease severity and increased plant growth would be further evaluated via more biochemical parameters such as indole acetic acid production (IAA) and total antioxidant status (TAS)