Study On Transmit Characteristic And Control Techniques Of Pine Wilt Disease

In this paper, we reported the feature of transmission number of pine wood nematodes(PWN), the screening test of nematocides and the safety assessment of nematicides. The results provides some theoretical basis and techniques for controling pine wilt disease. The main results are summarized as follows:1. Host plant species had no significant influence on number of PWN transmitted by adults. In course of adults supplementary nutrition, number of PWNs transmitted by adults had no significant difference among most observing records (eyery other 2 days) . In the adults of 30 intar course, there were 1～2 number peaks of PWNs. There were significant difference or very significance difference between amount of nematodes fastigium and other time .2.When adults were reared on the branches of five pine species,adults have obvious choice among different pine species.Adults prefered to feed [ Cedrus deodara (Roxb) Loud], P.massoniana and P.elliottii, and dislike to feed P.elliottii and P.thunbergii.3. The number peak of nematodes transmited by adults occurred after the feeding volume peak. There were no close correlation of function between number of nematodes and feeding volume.4.By bioassay of 19 kinds of nematicides, we selected 6 kinds of nematicide. The results of field test showed that 6 kinds of nematicides had obvious treating effect on infected trees. Field tests indicated that the biomass of above-ground tree could be used as dosage basis.5. After the pine trees inoculated with PWNs, we studied the activities of protective enzyme in the needle. Reaults indicated that the changes of activities of protective enzyme in the pine needle could served as one of early diagnostic reference.6. After the infected pine trees were injected with nematicides, we studied on activities of protective enzyme in the needle. We found that activities of protective enzyme in the pine needle hadn't significant difference between test and control trees. The results showed these nematicides were safety to pine trees.