计划烧除对松材线虫的影响

Effects of prescribed burning on Bursaphelenchus xylophilus

【目的】松材线虫病的爆发,给湖南松树造成巨大损失。探索火干扰对松墨天牛和松材线虫病的防治效果,为控制松材线虫病的扩散蔓延提供理论依据。【方法】以湖南省宁乡市道林镇的马尾松人工林为试验林分,设置健康林分(对照林分Ⅰ)、感染松材线虫病未防治林分(Ⅱ)以及感染松材线虫病且经过防治林分(Ⅲ)3种样地各6块,其中3块为对照样地,3块为计划烧除样地,通过低强度计划烧除,火干扰后跟踪调查松墨天牛及其松材线虫携带数量,对松墨天牛种群密度以及松材线虫病的防治效果进行了研究。【结果】火烧前后Ⅰ、Ⅱ、Ⅲ类计划烧除样地松墨天牛雌成虫数量分别减少了88.24%、75.00%和94.74%,雄成虫数量分别减少了77.78%、81.82%和88.89%,显著低于火烧前(P<0.05);对火烧前后Ⅰ、Ⅱ、Ⅲ类样地每期诱捕的松墨天牛雌雄成虫总数进行统计分析,发现Ⅱ-2的防治效果最好;火烧后的10到20 d内,计划烧除试验样地的雌、雄性松墨天牛成虫携带松材线虫数量变化显著,雌性天牛携带松材线虫的平均值从1135条/头降低到6条/头,雄性天牛平均携带量从397条/头下降到35条/头。【结论】计划烧除能够有效降低松墨天牛种群密度,减少松材线虫携带量,从而对控制松材线虫病的扩散蔓延和阻止松材线虫病的爆发,具有重要的理论与实践意义。

【Objective】Bursaphelenchus xylophilus became one of the most damaging forest pests in recent years in Hunan province,where it still caused remarkable losses of pine trees.In order to explore the effect of fire disturbance on the prevention of Monochamus alternatus and B.xylophilus,and provide theoretical basis for controlling the spread of Bursaphelenchus xylophilus.【Method】Pinus massoniana artificial forest was taken as the object of study in Daolin town,Ningxiang city,Hunan province.Three kinds of forest were selected,such as healthy forest of Pinus massoniana(controlⅠ),infected forest without prevention(Ⅱ),infected forest with prevention(Ⅲ).Then,6 plots were set in every object forest.Three were the control plot,and the other three were carried by fire disturbance.The number of M.alternatus and B.xylophilus before and after fire disturbance was investigated continuously.Population density of M.alternatus and control efficacy of pine wilt disease were studied after low intensity prescribed burning.【Result】The quantity of female M.alternatus in three kinds of fire disturbance plots were reduced 88.24%,75.00%and 94.74%,respectively,while the male reduced 77.78%,81.82%and 88.89%before and after fire.There were significant differences of the quantity of M.alternatus before and after prescribed burning(P<0.05).The quantity of M.alternatus adults in six plots before and after fire were analyzed.The prevention efficacious ofⅡ-2 was the best.Within 10 to 20 days after 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.【Conclusion】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 important theoretical and practical significance in M.alternatus and pine wilt disease prevention.