EFFICACY OF ANTAGONISTIC RHIZOBACTERIA ON THE CONTROL OF ROOT-KNOT NEMATODE, MELOIDOGYNE INCOGNITA IN TOMATO PLANTS

Three antagonistic bacteria, Bacillus thuringiensis, Bacillus subtilis and Pseudomonas flourescens, were evaluated throughout this investiga‌tion far the control of root-knot nematode, Meloidogyne incognita, on tomato plants. All antagonistic bacteria were used by adding 150 ml broth culture adjusted to 10 cfu/ml for each treatment. Both Bacillus thuringiensis and Pseudomonas fluorescens isolates were most effective in nematicidal activity against hatched juveniles and adults of M.incognita. On the other hand, the mortality levels of juveniles and adults of M.incognita increased with the highest concentrations of bacterial cells (105, 108 and 5 x 108 cfu/ml). Generally, the percentage of gall formation and root-gall index were decreased when the antagonistic bacteria were introduced prior to nematodes compared to the simultaneous introduction of both the nen-atode and bacteria. Furthermore, it can be concluded from the obtained data that plant parasitic nematodes were subjected to a wide range of anutibiotic-producing antagonists Ps. flourescens or sporecrystal mix-tures of B.subtilius, and B.thuringiensis, respectively.