Toxicity And Control Efficiency Of Different Nematicides To Southern Root-knot Nematodes, Meloidogyne Incognita

In this study, the toxicity and control efficacy of non-fumigation nematicides and Fumigation nematicides to the southern root-knot nematode (Meloidogyne incognita) were tested both in the laboratory and in greenhouse. The tested fumigation nematicides include metham- sodium, dazomet, 1, 3- Dichloropropene·Chloropicrin, and the tested non- fumigation nematicides include abamectin , cadusafos, fosthiazate and carbosulfan. The results were summaried as follows:1. The effects of 4 non- fumigation nematicides at different concentrations on egg masses hatching and juvenile of Meloidogyne incognita were investigated in laboratory. The results showed the toxicity of the 4 non- fumigation nematicides appeared to mainly reduced the motility and infectivity of the J2. Abamectin had a strong inhibition ability to the hatch of the eggs either in a egg mass or individual egg, and J2 mobility and infectivity were also significantly reduced; Cadusafos mainly inhibited the mobility of the J2; Fosthiazate mainly inhibited the J2 mobility and infectivity; Carbosulfan had a inhibition ability to the J2 mobility.2. The effects of 3 fumigation nematicides at different concentrations on J2 of Meloidogyne incognita were investigated in laboratory. The results showed that the mortality of the 3 fumigation nematicides at 25°C was increased as the time goes. The optimal temperature of metham-sodium was≥35°C, while The optimal temperature of dazomet and 1, 3- dichloropropene·chloropicrin were≥40°C.3. The effects of different nematicides on the Meloidogyne incognita were also evaluated on potted tomato plants. The results showed abamectin, fosthiazate and chloropicrin were effective against M . incognita infection. It significantly reduced the mumber of J2 survived in soil. When abamectin applied at 2mg / kg, cadusafos applied at 25mg / kg, fosthiazate applied at 10mg/kg, carbosulfan applied at 60mg / kg, their control efficacy were 80.64%, 89.01%, 84.44 % and 40.32% respectively, 35% Metham- sodium AS was applied at 20mg/kg, 98% dazomet GC was applied at 20mg / kg, 94.1%1, 3- dichloropropene·chloropicrin EW was applied at 200mg/kg, their control effectiveness were 92.49%, 84.84% and 95.59% respectively.4, Field efficiency trials of nematicides showed that the abamectin, fosthiazate and 1, 3- dichloropropene·chloropicrin had good control against M. incognita, when 0.5% abamectin GR applied at 4kg/667m2, 10% fosthiazate GR applied at 4kg/667m2, 94.1%1, 3- dichloropropene·chloropicrin EW applied at 40kg/667m2, their control effectiveness were 73.76%, 88.76% and 79.30% respectively.