Nematicidal activity of two Jordanian strains of Bacillus thuringiensis on root-knot nematodes

Abstract

The effects of two local strains of Bacillus thuringiensis, Bt. pakistani (H13) and Bt. entomocidus (H6), on hatching and mortality of two root knot nematode species, Meloidogyne incognita and M. javanica, were studied under laboratory conditions. Two concentrations, 105 and 106 viable spores/ml, of each Bt strain were tested. Exposure of juveniles to 106 viable spores/ml caused 100% mortality of juveniles of both species of nematode. Similarly, significant reduction of hatch was observed from eggs within the gelatinous matrix or freed eggs exposed to 106 viable spores/ml of both Bt strains. At the lower concentration of Bt spores, significant reduction in hatch was detected with freed eggs of M. incognita but not with eggs of M.javanica. No reduction of hatch from egg masses of either species was found after exposure to 105 viable spores/ml.