摩泽蒲螨携带杀虫真菌靶向防治光肩星天牛

An Effective Method for Biological Control of Anoplophora glabripennis(Coleoptera:Cerambycidae)by Using a Vector Mite,Pyemotes moseri(Acarina:Pyemotidae),Carrying Insecticidal Fungi

【目的】探寻一种利用蒲螨作为生物媒介,将昆虫病原真菌孢子传播到光肩星天牛虫道中,最终使害虫感染真菌死亡的生物防治光肩星天牛新方法。【方法】通过摩泽蒲螨和杀虫真菌孢子粉联用,利用摩泽蒲螨携带真菌孢子进入天牛蛀道,实现杀虫真菌对天牛的有效感染。室外模拟防治试验,采用光肩星天牛危害的长1.0 m杨树木段插埋基部于室外土壤中,用蚊帐罩住,每个重复10个木桩、每个处理3个重复。设置4个处理组,各组释放装置内分别有摩泽蒲螨和球孢白僵菌、摩泽蒲螨和金龟子绿僵菌、金龟子绿僵菌和球孢白僵菌、摩泽蒲螨、空白对照组无螨无菌。统计防治试验前后排粪孔和羽化孔的数量,并在防治1个月后剖开木段,检查光肩星天牛幼虫是否被真菌感染。林间防治试验,于2021年8月前往酒泉市石河桥道班,选择危害严重的杨树作为中心母树,固定释放装置,1个月后统计防效,确定蒲螨携真菌孢子的传播直径。【结果】室外模拟防治试验结果表明:防治1个月后,摩泽蒲螨和球孢白僵菌处理组、摩泽蒲螨和金龟子绿僵菌处理组的木段排粪孔减少比例分别为77.0%和83.1%,且无新增羽化孔。剖开木段检查天牛蛀道发现,摩泽蒲螨和球孢白僵菌处理组、摩泽蒲螨和金龟子绿僵菌处理组的木段天牛平均死亡率分别为77.5%和85.0%,且木段内有感染真菌死亡的天牛幼虫,经过分子鉴定为试验释放的杀虫真菌。林间防治试验结果表明:距离母树直径10.0 m范围内的受害树,排粪孔减少均在50%以上。【结论】摩泽蒲螨作为媒介生物,能成功将真菌孢子传播到光肩星天牛幼虫蛀道中,病原真菌靶向性感染天牛幼虫并最终死亡,且水平传播直径为10 m。本研究采用的媒介法生物防治光肩星天牛,首次巧妙利用了微小的媒介生物蒲螨将杀虫真菌孢子带入虫道,最终有效地感染天牛幼虫并致死。该方法有望研发为一种防效显著、操作简便、绿色无污染的生物防治天牛新技术。

【Objective】The aim of this study was to develop a new method to transmit entomopathogenic fungi by a biological vector,Pyemotes moseri,to biologically control the long-horned beetle,Anoplophora glabripennis,efficiently.【Method】Pyemotes combined with entomopathogenic fungi spores was used as an approach to spread the entomopathogenic fungi spores into the larval galleries of the long-horned beetle for effective infection of the larvae.An outdoor simulated control test was carried out by using one meter damaged poplar trunks with the trunk base planted in soil and covered with mesh net.Each treatment was triple replicates and each replicate was made of ten damaged poplar trunks.Four treatment groups were set up,and the release unit in four treatments respectively included Pyemotes and Beauveria bassiana,Pyemotes and Metarhizium anisopliae,B.bassiana and M.anisopliae,Pyemotes.Blank control was sterile without mites in the release unit.The number of frass holes and emergence holes of long-horned beetle damaged poplar trunks was counted before experiments and re-counted after one month of treatments.After one month,the poplar trunks was split to check whether the larvae of A.glabripennis were infected by the entomopathogenic fungi.Field efficacy tests were conducted in Jiuquan city of Gansu province in August 2021.To fix the release unit on central poplar which was damaged by A.glabripennis in Shiquanhe Bridge forest maintenance region.After one month,the field control efficacy was investigated to confirm the effective control diameter of each release unit.【Result】The results of outdoor simulated control test showed that the proportion of frass holes in Pyemotes and B.bassiana,Pyemotes and M.anisopliae respectively reduced 77.0%and 83.1%compared to blank control,and there was no new emergence hole.The larvae mortality of Pyemotes and B.bassiana was 77.5%,Pyemotes and M.anisopliae was 85.0%.The larvae were infected by entomopathogenic fungi in split trunks from treatment of Pyemotes and B.bassiana,Pyemotes and M.anisopliae,which was confirmed the infection was caused by the entomopathens used in the tests.Field efficacy tests in Jiuquan indicated that effective control diameter of each release unit was 10.0 m where frass holes reduced more tahn 50%.【Conclusion】The vector,Pyemotes moseri can successfully transmit entomopathogenic fungi spores into the larval galleries of long-horned beetle and cause effective infection to larvae with a final mortality of 80%.Each release unit of P.moseri with fungi spores transmission diameter is 10.0 m.This vector transmission biocontrol for long-horned beetle is a firstly reported new method that the insecticidal entomopathogens are transmitted by the tiny vector P.moseri,and cause an effective infection to larvae with high mortality.This vector transmission biocontrol technique has a potential to be developed as an effective,easy operation and environmentally friendly new technique to control long-horned beetle.