白僵菌及其微胶囊剂孢子活力及对沙棘木蠹蛾幼虫的侵染

ACTIVITY OF MICROENCAPSULATION OF BEAUVERIA BASSIANA AND ITS INFECTION ON THE LARVAE OF HOLCOCERUS HIPPOPHAECOLUS

白僵菌是昆虫的重要病原真菌之一,用于防治多种农林害虫,但环境湿度是影响防治效果的重要因素。因此研究白僵菌的新剂型,提高白僵菌孢子萌发率具有重要意义。本论文在室内设立不同相对湿度,比较白僵菌分生孢子及其微胶囊剂活性。结果表明,随着相对湿度的增加孢子萌发率也增大。水悬液分生孢子萌发率最高达55%,最低为8%;氯化钙悬液孢子萌发率不足10%;微胶囊剂孢子萌发率可高达91%,最低为33%。室内模拟野外条件测定相同分生孢子浓度下的白僵菌水悬液和及其微胶囊剂对沙棘木蠹蛾幼虫的侵染,沙棘木蠹蛾幼虫的死亡率分别为45.54%和84.54%,说明白僵菌微胶囊剂对沙棘木蠹蛾幼虫的侵染明显高于其分生孢子水悬液。

Beauveria bassiana is one of the most important entomogenous fungi,which has been used in controlling agriculture and forestry pests.The humidity is one of the most important factors in which influence the control effect.Therefore,it is very important to improve B.bassiana spore germination rate condition and explore the new formations for the fungi.In order to get a good control effect,B.bassiana.conidiospore microencapsulation and its germination were studied.The results showed that spore germination rate increased as the relative humidity increased.The conidiospore distilled water suspension germination rate was 55% and 8%,respectively at higher and lower humidity.Conidiospore calcium chloride suspension germination rate was less than 10%.Microencapsulation spore germination rate was 91% and the 33% at higher and lower humidity.Mimic the field conditions,infection of both formations of the conidiospore to the larvae of Holcocerus hippophaecolus were studied at the laboratory.The formations were conidiospore distilled water suspension and microencapsulation.The mortality caused by the microencapsulation and the water suspension was 45.54% and 84.54% respectively.The infection rate of the microencapsulation on larvae of H.hippophaecolus was obviously higher than that of conidiospore water suspension.