Population Dynamics Of Bursaphelenchus Xylophilus With Relationship To The Inner Habiting Fungi Of Pinus Spp.

Pine wilt disease(Bursaphelenchus xylophilus(Steiner & Buhrer)Nichle), a destructive forest disaster, has been listed as an important plant quarantine object by many countries. As a result, to study the functionality of inner habiting fungi on pine wilt disease, has been of great concern academically.This study sough to explore how the pine inner habiting fungi changed after being infected by the pine wood nematode, to elucidate the influence of the pine inner habiting fungi on the population dynamics of pine wood nematode preliminarily and to set forth a theoretic foundation for the study of pine wilt disease. It will be consequential to find a new, but effective method of biological control for this disease. The main results are summarized as follows:1. 1285 isolates of fungi were obtained from the 99 samples of xylem collected from Pinus thunbergii, P. massoniana, P. elliotti and representative broadleafs in Zhejiang province in which 1060 isolates were identified as Trichoderma, Penicillium, Sphaeropsis, Botryosphaeria, Pestalotia, Alternaria, Rhizoctonia, Acremonium, Gliocladium, Aureobasidium, Avscochyta, Fusarium, Melanconium, Beltrania, Ceratocystis, Tolura, Phoma, Peyroneuaea, Cytospora, Graphium and Arthroconiora etc. Trichoderma, Penicillium, Sphaeropsis, and Botryosphaeria were dominant genus.2. An obvious correlation were found between the inner habiting fungi and the population dynamics of pine wood nematode at different health state in P. thunbergii, but it does not exist in P. massonian.3. There were clear correlation between the inner habiting fungi and the population dynamics of pine wood nematode within different ecosystems in P. thunbergii and P. massoniana, meaning that the amount of pine wood nematode changes with the inner habiting fungi.4. The mycoflora varied with different pine host, and thus lead to varied resistances of pine to the pine wilt disease. The resistance of pine to the pine wilt disease also changes with varied forest structure due to different inner habiting fungi.