Original Research Article Exopolysaccharides (EPS) mediated Induction of systemic resistance (ISR) in Bacillus - Fusarium oxysporum f.sp. lycopersici pathosystem in tomato (var. PKM-1)

*Corresponding author A B S T R A C T The positive role of Bacillus exopolysaccharides (EPS), obtained from different bioformulations viz., vegetative cells, natural biofloc and artificial biofloc, on the maximization of plant growth and bio-control against the wilt disease (Fusarium oxysporum f.sp. lycopersici) in tomato was studied under potculture condition.Among the different bioformulations of Bacillus cells, the EPS obtained from natural biofloc of Bacillus reduced the wilt disease (Fusarium oxysporum f.sp. lycopersici) incidence to a higher level followed by the application of EPS, obtained from artificial biofloc and vegetative cells. Regarding the optimization of different concentrations of purified Bacillus EPS viz., 100, 200, 300 ppm on the wilt disease incidence of tomato revealed that the application of the purified EPS, obtained from natural biofloc of Bacillus, at 200 ppm concentration level could effectively reduced the wilt disease incidence of tomato to a higher level when compared to other EPS concentrations, obtained from other bioformulations of Bacillus. The results of the present study clearly revealed the dual role of Bacillus exopolysaccharides (EPS) on the maximization of plant growth as well as the bio- control against F. oxysporum f.sp. lycopersici in tomato whereas, the application of ISR inducing chemicals resulted with reduction in tomato wilt disease incidence alone. Moreover, the Bacillus EPS, obtained from natural biofloc, at a concentration of 200 ppm level could be optimized as effective one for the control of ISR mediated wilt disease incidence in tomato.