【作者】 汤陈生；

【导师】 黄金水； 陈顺立；

【作者基本信息】 福建农林大学 ， 森林保护学， 2004， 硕士

【摘要】 本项目研究于2001～2004年在福建省林科院林研所森保室、云霄县、惠安县以及光泽县的欧美杨引种等地进行。以自行筛选出的选择性培养基，对森保室现有的和野外采集的17种白僵菌（Beauveria bassiana）菌株进行优良白僵菌菌株的筛选，然后将筛选出的马尾松毛虫（Dendrolimus punctatus）、杨树舟蛾（待定种）、松墨天牛（Monochamus alternatus）优良白僵菌菌株扩大培养生产后，进行不同剂型、不同施菌量的林间防治试验，并对超低容量喷洒白僵菌油剂的马尾松林进行生物多样性调查，主要研究结果如下： 从野外采回的天然僵虫携带杂菌较多，给分离带来很大的麻烦，为高效地分离出较纯的白僵菌菌种，用硫酸铜、结晶紫、氯霉素、百菌清和可杀得可湿性粉剂等5种抑菌剂进行选择性培养基的筛选，以PDA培养基为基础，筛选出对供试白僵菌菌株选择性较强的培养基，其配方为：马铃薯200g，葡萄糖20g、蛋白胨10g、琼脂20g，硫酸铜1.0 g·L^-1，蒸馏水1000mL。该选择性培养基分离出的白僵菌菌落数比对照（PDA培养基）多5.4～11.1个·皿^-1，而杂菌却少了2.7～10.1个·皿^-1，而且生长速度为对照PDA培养基的1.28倍，提高了白僵菌菌种的分离和纯化的效率。 以该选择性培养基对17种白僵菌菌株进行优良白僵菌菌株的筛选，选出的马尾松毛虫优良菌株Byx、杨树舟蛾优良菌株Bjy和松墨天牛优良菌株Bma13，在菌落形态、生长速度、产孢量、孢子萌发率以及毒力方面，均表现出较其它同期菌株优良的性状。这3个菌株在选择性培养基上的菌苔都很厚、菌落圆形、边缘整齐、厚度均匀、有明显的轮纹，其中分离自福建云霄的马尾松毛虫天然僵幼虫的优良菌株Byx平均每天能扩展3.21mm，产孢量为3.78×10⁸个·cm^-2，24h内孢子萌发率达97.24％，在汤陈生白僵菌优良菌株及林间使用剂型的研究毒力方面，20d幼虫校正死亡率达97.8%，处理僵虫率达95.5%，用该菌株生产出白僵菌粉，并自制成粉炮，每0.667hm，放20个，15d时僵虫率达80%以上，30d时幼虫校正死亡率达%.1%;分离自福建光泽的杨树舟蛾天然僵幼虫的优良菌株街y，产抱量为3.81 xl了个·cm一2，分生抱子在24h内萌发率达96.67%，在毒力方面，20d幼虫校正死亡率达94.4%，处理僵虫率达92.2%，用粉炮进行林间防治，15d时僵虫率达80%以上，3Od时幼虫校正死亡率达90.7%:分离自福建武夷山的松墨天牛天然僵蛹的优良菌株Bmal3产抱量达323 x 105个·cm一2，分生抱子在营养液中18h的萌发率达到416%，对松墨天牛幼虫的僵虫率达100%。而且这3个菌株都表现出比其它菌株同期对害虫感染速度快、致死率高，对低虫口的防治小区的树叶保护得较好，可作为生产上推广应用的菌种。 抱子萌发快慢可以直接影响菌株侵染寄主的可能性，抱子萌发速度越快，寄生的概率会越高，同时抱子萌发率又是代表一个菌株活力的指标。白僵菌分生抱子在温度25一28℃、相对湿度95%以上时，萌发率高达84.6%以上，致死速度快，LTS。<4.84天，温度低于25℃、高于28℃或相对湿度在95%以下都使抱子萌发率卜降，以致对松毛虫的致病力显著下降，所以白僵菌防治应选择春、冬季的雨后或清晨雨露未干时使用为宜。 应用筛选出的优良菌株进行不同剂型、不同施菌量的林间防治试验，筛选出对马尾松毛虫、杨树舟蛾等食叶害虫最好的剂型是超低量油剂和超低量复合油剂，乳剂次之，其中超低容量油剂以施菌量巧万亿或20万亿个·hm一2为宜，超低量复合油剂以施菌量10万亿个·Iun一2的油剂中添加3.0 mL·hm一2的杀灭菊醋为最佳。施菌量巧万亿个·hm一，的白僵菌超低容量油剂和乳剂使用后，马尾松毛虫的校正死亡率达94.8%和76.4%，白僵率达82.8%和75.5%，针叶受害率7.6%和10.4%，杨树舟蛾的校正死亡率达95.4%和79.3%，白僵率达84.6%和77.3%，针叶受害率39.7%和48.4%:施菌量20万亿个·hm一2的白僵菌超低容量油剂使用后，马尾松毛虫的校正死亡率达99.7%和99.5%，白僵率达88.1%和82.3%，针叶受害率7.1%和7.3%，杨树舟蛾的校正死亡福建农林大学硕士研究生学位论文率达100%和99.6%，白僵率达90.2%和83.7%，针叶受害率犯.3%和336%;在施菌量10万亿个·hm一2的油剂中添加3.0 mL·hm一2的杀灭菊酷后，做成的白僵菌复合剂，对马尾松毛虫的校正死亡率达95.2%，白僵率达72.3%，针叶受害率7.6%，对杨树舟蛾的校正死亡率达93.8%，白僵率达67.9%，针叶受害率26.1%。但是，随着时间的推迟，相同剂量的四种剂型防治效果差异不显著，而且在施菌量低时，四种剂型防治效果差异也不显著，所以在低虫口密度时，那些山高缺水、交通不便的林分也可选用白僵菌粉炮防治，但用菌量不能太低。 用白僵菌菌膏和溶液2种剂型、5种施药方法防治星天牛、多纹豹蠢蛾和相思拟木蠢蛾，结果表明菌膏涂孔法的效果最佳，防治3种害虫分别达77.0%、96.2%和93.8%;其次是采用菌液塞孔法，效果分别达55.6%、71.9%和57.8%;而用菌液喷干、菌粉撒干和菌膏涂干防治，白僵菌与害虫虫体接触的机会较少，防治效果较差。 对喷洒白僵菌超低容量油剂的马尾松林进行生物多样性的调查研究，包括使用前后的物种丰富度更多还原

【Abstract】 In the period of 2001-2004, the study was carried out in Fujian academy of forestry, Yunxiao county, Hui’an county and Guangzhe county. Three excellent strains of Beauveria bassiana against dendrolimus punciatus, notodontidae in populus euramericana and monochamus alternatus were screened out from seventeen strains of Bb, which preserved in the laboratory and collected from yield. By magnification, the screened super strains were used to control in forest with different formulations and fungus application amount. At the same time, we investigated ecological diversity in pinus massoniana stand, where was ultra-low-volume spraying of oil formulation of Bb. The main conclusions are given as follow:Because natural body with many competed moulds caused trouble to isolate, five fungistasis such as CuSO4, Crystal violet, Chloramphenicol, Dacotech WP and Kocide WP were used to screened purer strains of Bb. The selective medium had high selection for Bb, which consisted of the following ingredients per litre distilled water: potato 200 g, glucose 20 g, fine peptone 10 g, agar 20 g, CuSO4 1 g. Use of the selective medium could increase efficiency of isolation and purify of Bb, which increased from 5.4 to 11.1 colony of Bb and decrease from 2.7 to 10.1 colony of competed moulds, and growth rate of the mycelium of Bb in it had 1.28 times as PDA culture medium.The seventeen strains of Bb were tested on colony morphology, growth rate of mycelium, sporulation, spore germination rate and virulence. The results showed that threescreened excellent strains named Byx, Bjy, Bma13 were the best on other characters, which lawns were chick, colonies were round, edges were regular, thickness were uniform and veins were clear. Firstly, the screening strain from dendrolimus punctatus in Yunxiao county had excellent characters, which sporulation is 3.78 X 10s per square centimeter and spore germination rate is 97.24% within twenty-four hours. The toxicity determination showed that the mortality reached 97.8% and white cadaver rate was 95.5% on the twentieth day, and control in forest with twenty powders per 0.667 hectare indicated that white cadaver rate was more than 80% on the fifteenth day and the mortality reached 96.1% on the thirtieth day. Secondly, the screening strain from notodontidae in populus euramericana in Guangzhe county had excellent characters, which sporulation is 3.81 X108 per square centimeter and spore germination rate is 96.67% within twenty-four hours. The toxicity determination showed that the mortality reached 94.4% and white cadaver rate was 92.2% on the twentieth day, and control in forest with powders indicated that white cadaver rate was more than 80% on the fifteenth day and the mortality reached 90.7% on the thirtieth day. Lastly, the screening strain from monochamus alternatus in Wuyi city had excellent characters, which sporulation is 3.23 X 108 per square centimeter and spore germination rate is 41.6% on eighteenth hours in nutrient solution. The toxicity determination showed that white cadaver rate was 100% against monochamus alternatus. Therefore, they would have a significant protective effect on the controlling stands where had less pests, and they could be widely put into use.The spore germination rate can directly affect on the possibility of host being parasited, because the more rapidly the spore germinated, the higher probability of host were parasited, at the same time, the spore germination rate is a index of the vigor of the strain. Under the condition of more than 95% relative humidity and from 25 C to 28 C, the spore germination rate reached more than 84.6% and mortality rate accelerated with LT50was below 4.84 days, however, the spore germination rate reduced that was the spore apparently decreased pathogeny of pine caterpillar when relative humidity was below 95%, or temperature was above 28 C and below 25 C. Therefore, controlling of Bb in forest should be performed after raining or in the morning in Spring or Winter.The forms of oil formulation, emulsion, water agent and powder o更多还原