An experiment was conducted in a greenhouse to evaluate the biological performance of some agrochemical and biological agents against root-knot nematode on tomatoes planted in clay soil. The antagonistic bacterium Pseudomonas flouroscence was proved to be the most effective tool suppressing the infection of root-knot nematodes on tomatoes during the period of inspections. The mean of population reduction of P. flouroscence was (79.4%), followed by the mixture of antagonistic fungus and bacterium Trichoderma harazianum plus Pseudomonas flouroscence (73.0%), then fosthiazate (60.3%), while the least effective one was abamectin (22.5%).
On the other hand, abamectin applied as soil drench gave the highest reduction percentage (81.6 % of root galls / 5g roots) followed by oxamyl (62.4%), then fosthiazate (61.5%). Carbofuran recorded the least reduction percentage of 33.1 % of root galls /5g roots.
Meanwhile, abamectin gave the highest reduction percentage on egg masses / 5g roots (79.1 % ), followed by oxamyl and P. flouroscence giving 61.4 and 39.9 reduction percentages. The least effective treatment was Trichoderma harazianum which increased the egg masses by 18.8 %.
Some treatments showed an indirect effect on the root and shoot system length and weight. The antagonistic fungus Trichoderma harazianum was the superior treatment which increase the root system length by 39.1 %, whilst abamectin didn't show any increase.
Trichoderma harazianum as well as fosthiazate proved to be the most effective treatment on the root system fresh weight as they gave 86.8 and 85.5% increase, respectively. Abamectin was the least effective treatment giving 5.3% increase.
On the other hand, T. harazianum was effective and gave the highest increase percentage of shoot system length followed by oxamyl (54.9 and 46.8%, respectively). Meanwhile, the same trend was obtained in case of shoot system weight giving increases of 87.8 and 81.9%, respectively. Abamectin treatment was the least efficient on its effecton both root system length and weight increase.