This experiment was conducted under greenhouse conditions in the experimental farm station of Moshtohor, Fac. Agric., Benha Univ., during 2012 season. The efficient antagonistic bacterial strains Bacillus subtilis B38 and Pseudomonas fluorescens B103 either individually or in a mixture was evaluated for their activity against soil-borne pathogens of root-rot disease and wilting fungi compare with fungicide on tomato. Damping- off, survived plants, disease severity, enzymatic activity, plant growth characters, phenol compounds, peroxidase activity and tomato yield were recorded. The treatments of tomato plants with fungicide and bioagents (B. subtilis B38 and Ps. fluorescens B103) significantly decreased the percentage of damping-off and disease severity of infested tomato with F. oxysporum, R. solani and S. rolfsii compared to un-inoculated ones, while, the percentages of survived plants significantly increased when tomato was treated with fungicide or bioagents. In addition, data showed that the individual treatment of B. subtilis B38 was found more effective than Ps. fluorescens B103 for suppression the soil-borne pathogenic fungi. Moreover, inoculations of tomato with either individually or in a mixture exhibited significant increase of phosphatase, chitinase and dehydrogenase activities in tomato rhizosphere. Data also revealed that all growth characters and yield components were significantly increased especially with dual inoculation by B. subtilis B38 and Ps. fluorescens B103. Also, the values of free, combined and total phenols as well as peroxidase activity were significantly increased when tomato plants were treated with biocontrol agents either individually or in mixed culture. It could be stated that the dual application of B. subtilis B38 and Ps. fluorescens B103 was found more effective for controlling the soil-borne fungi. Although, this application was still less than chemical control but it was the best schedule for controlling fungal disease incidence in an ecofriendly system. |
