Screening of native bacillus strains to induce systemic resistance in tomato plants against fusarium wilt in split root system and its field applications.

A study was carried out to screen some bacillus strains for their ability to induce systemic resistance against fusarium wilt of tomato under both split root system and field conditions. Fourteen bacillus strains were used for initial screening of resistance induction under split root design in green house evaluations. Increase in quantities of defense related biochemicals as total phenolics, PO, PPO and PAL enzymes were examined to document induced systemic resistance (ISR) phenomenon in tomato plants under influence of these bacterial inducers. Two Bacillus strains viz., B. fortis IAGS162 and B. subtilis IAGS174 provided maximum control over fusarium wilt under split root system. Calorimetric assays proved highly significant for defense related biochemicals in tomato plants under the influence of these two bacterial strains. Talc based formulations of these two strains were prepaired to check their efficacy under field conditions. These not only provided protection against fusarium wilt, but also markedly enhanced growth and fruit yield of plants under field conditions. Our study clearly indicated the importance of these microbial organisms for suppression of Fusarium wilt and growth promotion in our agriculture system.