石斛象甲虫生真菌的分离鉴定及其毒力测定  

Toxicity Test and Identification of the Entomogenous Fungi Isolated from the Weevil on the Dendrobium nobile

作　　者：录丽平[1] 杨美林[1] 秦小萍[1] 张玲[1] 李秀娟[1] 郝妮娜[1] 

机构地区：[1]云南农业大学植物保护学院,云南昆明650201

出　　处：《中国生物防治学报》2008年第S1期28-31,共4页Chinese Journal of Biological Control

基　　金：国家自然科学基金(30660108)资助

摘　　要：用石斛象甲上分离出来的两株蜡蚧轮枝菌菌株Ⅰ和菌株Ⅱ,采用Hall生物测定方法,测定了其致病性和对烟蚜的毒力。结果表明:在10⁸孢子/ml浓度下,石斛象甲的喙、足在5d后有菌丝产生,8d后虫死亡,虫体表面布满菌丝。其中菌株Ⅰ致病性最强,其LC₅₀在24～96h明显小于菌株Ⅱ;120h时,菌株Ⅰ的LC₅₀为3.27×10⁵孢子/ml,菌株Ⅱ的LC₅₀为1.32×10⁵孢子/ ml。在同一数量级（10⁷、10⁶、10⁵）,菌株Ⅰ的LT₅₀最短;两菌株在120h内都能使大量烟蚜感染致死,且随着孢子浓度的增加LT₅₀都减小。研究表明从石斛象甲上分离出来的蜡蚧轮枝菌对石斛象甲具有致病性,对烟蚜有较高的生物活性。The pathogenicity test to weevil and the toxicity test to Myzus persicae used two Verticillium lecanii isolated from weevil on the Dendrobium nobile,using the method described by Hall.The results showed:the consistency is 10~8 spore/ml,the weevil's haustellums and legs grow mycelium after 5 d,the insects died and it's surface covered with mycelium after 8 d,strainⅠis most pathogenicity in two strains,it's LC_(50) is lower than the strain 2 in the 24-96 h,the LC_(50) of the isolates 1 is 3.27×10~5 spore /ml and the strainⅡis 1.32×10~5 spore/ml,when the consistency is 10~5-10~7 spore/ml,the LT_(50) of strainⅠis shortest.Lots of M.persicae died in 120 h because of infected by the strains,the LT_(50) all reduces with the consistency increase.Research showed both strains have pathogenicity to weevil and high biology activities to M.persicae.

关 键 词：石斛 蜡蚧轮枝菌 分离 毒力测定 

分 类 号：S476.12[农业科学—农业昆虫与害虫防治]