Growth and decline of arboreal fungi that prey on Bursaphelenchus xylophilus and their predation rate

Pine wilt disease caused by pine wood nema-todes is a deadly disease of the genus Pinus requiring strong quarantine measures. Since its discovery, it has been widely distributed throughout the world. China is one of the coun-tries with a severe rate of infections due to its abundant pine resources. In this study, nematode-trapping fungi were collected from pine trees in Ninghai City, Zhejiang Prov-ince, which is the key area of pine wilt control in Febru-ary, May, September, October and November. The results showed that nematode- trapping fungi of pine are abundant, especially the number and species detected in each month and are quite different; species of fungi in July, Septem-ber and November were more numerous and had higher separation rates. The dominant species in November was Arthrobotrys oligospora followed by Arthrobotrys cladodes; July and September it was A. cladodes. In each part of the tree, A. cladodes was the most widely distributed with a high separation rate. Therefore, it is the dominant fungal species in the area. Arboreal Bursaphelenchus xylophilus-trapping fungi are dependent on pine wood nematodes, and none were isolated from healthy pine trees. More arboreal B. xylophilus-trapping fungi were found under the bark than in the xylem. There is a close relationship between arboreal B. xylophilus-trapping fungi and pine wood nematodes. How to make use of these resources to reduce the damage of pine wood nematode fusarium is the focus of future research.