COMPARATIVE EFFICACY OF NEMATICIDES AND NEMATOCIDAL PLANTS ON ROOT-KNOT NEMATODES

The nematicides ethylene dibromide and aldicarb were compared to Tagetes minuta L. and Datura stramonium L. for control of root-knot nematodes. Ethylene dibromide gave the most effective reduction of galling and the poorest shoot growth and fruit yield, though its effects were reduced under field conditions. Aldicarb gave the highest shoot growth and fruit yields. It also reduced the galling intensity significantly more than T. minuta or D. stamonium. Datura stramonium had significantly greater suppressive effects on gall formation than did T. minuta. The two nematicidal plants stimulated tomato growth significantly more than the control. The methods used in this test may be ideal for comparing the relative efficacies of two or more nematicides with nematicidal plants on root-knot nematodes. The economic implications of these methods and results obtained on the management of root-knot nematodes are discussed.