利用花绒寄甲防治杨树云斑天牛的研究

Biological Control of Batocera horsfieldi (Coleoptera:Cerambycidae) by Releasing Its Parasitoid Dastarcus helophoroides(Coleoptera:Bothrideridae)

在湖南和湖北省选取9个云斑天牛危害的杨树林作为试验林,释放云斑天牛的寄生性天敌花绒寄甲卵和成虫开展生物防治云斑天牛试验。通过调查天敌释放前后被害株数和株虫口数2个指标对花绒寄甲的防治效果进行评价。结果表明:林间释放这种寄生性天敌的卵和成虫均对云斑天牛有良好的控制效果。在释放花绒寄甲卵的3个试验林中,平均株虫口校正减退率为83.27%;平均被害株校正减退率为74.33%;在释放花绒寄甲成虫的6个试验林中,平均株虫口校正减退率为84.23%;平均被害株校正减退率为75.65%。通过对释放花绒寄甲卵和成虫后当年和第2年调查的防治结果进行比较,表明释放天敌成虫的防治效果略好于释放卵的林分,但二者差异不显著。由于人工繁殖花绒寄甲成虫的成本远高于卵,因此,在生产中大面积防治云斑天牛时,采用释放花绒寄甲卵的方法比较经济。

In this study,the parasitoid Dastarcus helophoroides（Coleoptera：Bothrideridae） was released for sustainablly controlling the longhorn beetle Batocera horsfieldi（Coleoptera：Cerambycidae） ,an important stem-borer in poplars in the south of China. Adults and eggs of D. helophoroides were released in the fields at nine plots in the Hunan and Hubei Provinces. Control effect was evaluated by two investigation indexes,i.e.,infested trees number and larvae density. Results showed that, releasing both eggs and adults was able to effectively control B. horsfieldi. Among three plots of releasing the parasitoid eggs, the mean correction reducing rate of the longhorn beetle larvae per tree was 83.27 %, and the mean correction reducing rate of infested trees was 74.33 % . Among six plots of releasing the parasitoid adults, mean correction reducing rate of the longhorn beetle larvae per tree was 84.23 %, and the mean correction reducing rate of infested trees was 75.65 %. The controlling results by releasing adults of the parasitoid were a little better than releasing eggs of the parasitoid by comparing the controlling effect in the first and second year, however there was no significant difference between them. Considering higher cost of mass rearing the parasitoid adults than the eggs, it is suggested to release the parasitoid eggs for control!ing the severe-damaged longhorn beetle in forests.