EFFECTS OF PRESCRIBED BURNING ON PINE WOOD NEMATODE (BURSAPHELENCHUS XYLOPHILUS).

Bursaphelenchus xylophilus became one of the most damaging forest pests in recent years in Hunan province, and caused remarkable losses of pine tree. In order to explore the effect of fire disturbance on the prevention of Monochamus alternatus and B. xylophilus. forests dominated by Pinus massoniana were taken as the object of the study in Daolin town, Ningxiang city, Hunan province, China. Three kinds of forest were selected, such as healthy forest of Pinus massoniana (Control I), infected forest without prevention(II), and infected forest with prevention(III). Then, 6 plots were set in every object forest. Three were the control plot, and the other three were treated with prescribed burning. We continuously investigated the number of M. alternatus and B. xylophilus before and after low intensity prescribed burning. The results indicated that the quantity of female M. alternatus in the three kinds of fire disturbance plots were reduced by 88.24%, 75.00% and 94.74%, respectively, while the males were reduced by 77.78%, 81.82% and 88.89% before and after the fire. There were significant differences for the quantity of M. alternatus before and after the prescribed burning (P<0.05). The results showed that the prevention efficacy of II-2 was the best. Within 10 to 20 days after the fire, the quantity of B. xylophilus carried by M. alternatus changed significantly. The average quantity of B. xylophilus carried by female and male M. alternatus dropped from 1135 to 6 and from 397 to 35, respectively. It showed that prescribed burning could reduce the population density of M. alternatus and carrying quantity of B. xylophilus of each M. alternatus. So prescribed burning could control the spread of pine wilt disease and prevent its outbreak. Prescribed burning has an important theoretical and practical significance in pine wilt disease prevention. [ABSTRACT FROM AUTHOR]