Evaluation of Some Jordanian Bt Strains against Two Species of Root-Knot Nematodes

Four jordanian strains of bacillus thuringiensis, (bt) i.e. bt jordanica, bt kurstaki, bt pakistani, and bt thuringiensis, and two reference strains bt israelensis and bt kurstaki were tested against root knot nematodes, meloidogyne incognita and m. javanica. exposing freed eggs or eggs within eggmasses to 106 viable spores/ml of each local strain resulted in either complete inhibition or few j2s hatching of both nematode species. lower concentrations (105 viable spores /ml) were less effective in reducing egg hatching. depending on the local bt strains, 100% mortality of j2 of both nematodes occurred either after 2, 4 or 6 days of exposure to the higher spore concentration. lower concentration of bt strains was less effective but with a significant increase of mortality of j2s of both nematodes