Effect of Pleurotus ostreatus on Dynamics of Meloidogyne arenaria Population and Control Effectiveness

The control effects and application methods of Pleurotus ostreatus on the peanut root-knot nematode disease, Meloidogyne arenaria, were systematically studied in the greenhouse. Results of pot experiments showed that P. Ostreatus could effectively reduce the 2nd-instar population density in the soil, and the larva reduced by 80% compared with the control. P. Ostreatus could markedly lower the infecting number of the peanut root-knot nematodes, the nematode density inside the root knots declined by 40.00% - 82.64%, and the peanut root knots also reduced by 86.96% - 94.03%. The fungus could defer the initial infection of M. Arenaria to the roots, the epidemic rate of the peanut root-knot nematode disease was significantly cut down, and the increase of root-knot changed from the way of Logistic curve in the control to the way of linear curve in the treatment. The final control effectiveness was about 80%. The results of pot trial also indicated that the control effectiveness is closely related to the application time and the amount of this fungus. The key factor affecting control effectiveness was the application time of P. Ostreatus in the soil and the suitable time was 20 days before sowing.