Institute of Plant Protection, Fujian Academy of Agriculture Sciences/Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests/East China Branch of the National Center for Agricultural Biosafety Science, Fuzhou, China.
Institute of Quality Standards & Testing Technology for Agro-Products, Fujian Academy of Agricultural Sciences/Fujian Key Laboratory of Agro-Products Quality and Safety, Fuzhou, China.
Arch Insect Biochem Physiol. 2022 Jul;110(3):e21908. doi: 10.1002/arch.21908. Epub 2022 Apr 25.
Entomopathogenic fungus as biological control agent plays a crucial role in the integrated management of insect pests. Metarhizium anisopliae Ma6 has been identified as a highly pathogenic strain against Phyllotreta striolata (Fabricius) (Coleoptera: Chrysomelidae), one of the most economically important and dominant insect pests damaging Brassica plants. The infection of M. anisopliae Ma6 on P. striolata was observed under stereomicroscopy and scanning electron microscopy (SEM), and biochemical defense responses of P. striolata adults after infection were investigated. The changes in total amino acids and free fatty acids, and the activities of protective enzymes, including catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD), in P. striolata adults were measured. In stereomicroscopy and SEM observations, a large number of mycelia were observed on the body surface of P. striolata on the 5th day after treatment by M. anisopliae. Many conidia were germinated and covered the body of P. striolata on the 7th day after treatment. The free fatty acid, total amino acid, CAT, POD, and SOD activities all showed an increased and then decreased trend. These results suggest that entomopathogenic fungal infection triggers the defense response of hosts, which induces changes in nutrients and antioxidant enzymes in P. striolata adults. Our findings provide useful information for understanding the potential for using M. anisopliae Ma6 as a biocontrol agent.
昆虫病原真菌作为生物防治剂在害虫综合治理中起着至关重要的作用。绿僵菌 Ma6 已被确定为一种对鳞翅目叶甲科重要的蔬菜害虫黄曲条跳甲（Phyllotreta striolata ）具有高致病力的菌株。本研究在体视显微镜和扫描电子显微镜（SEM）下观察了绿僵菌 Ma6 对黄曲条跳甲的感染，并研究了感染后黄曲条跳甲成虫的生化防御反应。测量了黄曲条跳甲成虫体内总氨基酸和游离脂肪酸的变化，以及保护酶（CAT、POD 和 SOD）的活性。在体视显微镜和 SEM 观察下，绿僵菌处理后第 5 天，大量的菌丝体出现在黄曲条跳甲的体表。绿僵菌处理后第 7 天，大量的分生孢子萌发并覆盖了黄曲条跳甲的体表。游离脂肪酸、总氨基酸、CAT、POD 和 SOD 的活性均表现出先升高后降低的趋势。这些结果表明，昆虫病原真菌的感染引发了宿主的防御反应，导致黄曲条跳甲成虫体内营养物质和抗氧化酶发生变化。本研究结果为利用绿僵菌 Ma6 作为生物防治剂提供了有用的信息。
