A greenhouse experiment was conducted in the experimental farm station of Fac. Agric., Benha Univ., during 2012 season to evaluate the efficient antagonistic bacterial strains Bacillus subtilis B38, Pseudomonas fluorescens B103 and Serratia marcescens either individually or in a mixture for their activity against root-knot nematode Meloidogyne incognita on tomato compared with nemaless and chemical nematicide. Damping- off, survived plants, nematode galls number and populations, enzymatic activity, plant growth characters, phenol compounds, peroxidase activity and tomato yield were recorded. Data show that mixture inoculations of bioagents were found to be more effective for significant reduction of damping- off and increased the survived plants of infested tomato with M. incognita and reduction of number of galls and nematode larvae population compared with each individual. Moreover, the mixture of bioagents was found to be more efficient than nemaless application in controlling of root-knot nematode M. incognita but still less than chemical application with nematicide. Also, the highest values of phosphatase, chitinase and dehydrogenase activities were observed with the application of mixture bioagents compared to either individually or other treatments. Moreover, data revealed that treated tomato with mixed inoculation of B. subtilis B38, Ps. fluorescens B103 and S. marcescens attained more significant values of growth characters and yield than nemaless treatment but still less than chemical nematicide. Also, inoculation with nemaless and the tested bioagents either individually or in mixed form succeeded to increase the total and conjugated phenols as well as peroxidase activity in infected plants. |
