44 isolates of fungi were isolated from the xylem of the Pinus thunbergii samples(healthy stem,weak stem and withered stem)infected by the pine wilt disease caused by pine wood nematode,Bursaphelenchus xylophilus,from infected trees at Zhoushan and Pinghu of Zhejiang Province in China,and these isolates were identified as:Trichoderma spp.,Penicillium spp.,Pestalotia spp.These identified isolates took 70.62% of total isolates of the fungi.Among the 12 isolates unidentified,one sporiferous fungus was found,the other 11 isolates were nonsporiferous.Trichoderma spp.was the dominant fungus in P.thunbergii,the total rate was 53.34%,followed by Penicillium spp.,18.89%.

The damage characteristics and spatial distribution of Sphenoptera sp. larvae population on Artemisia ordosica were analyzed by using biostatistics and geostatistical methods in order to effectively control the insect and to further study the damage characteristics and spatial distribution of the population. The results showed that the larvae of Sphenoptera sp. distributed on the whole plant, but showed a trend of increasing first and then decreasing from top to bottom. However, about 95% of the larvae were concentrated in the roots 8 cm underground. Four theoretical models (spherical, exponential, Gaussian, and linear) were used to represent the observed spatial correlation of larvae and it was found that the spherical isotropic model fitted the best with 3.12 m spatial dependence and 0.98 intensity of local spatial continuity. These indicated that the spatial distribution of larvae followed an aggregation distribution, and the aggregation points were primarily distributed in different areas of the woodland and then spread to the entire woodland.