一株扁角豆芫菁寄生菌的分离鉴定

Isolation and Identification of A Parasitic Bacteria from Epicauta impressicornis

目的:为摸清药用昆虫扁角豆芫菁Epicauta impressicornis Pic人工饲养过程中感染真菌病害的情况,对一株感染该虫的真菌进行分离鉴定。方法:利用扫描电镜和分子生物学方法对该菌株进行形态学和分子鉴定。结果:该菌株的内源转录间隔区(ITS)基因序列和β-微管蛋白(BenA)基因序列测序结果在GenBank登录号为ITS:MT825106,BenA:MT862132;系统发育树显示,该菌株与黄曲霉Aspergillus flavus、米曲霉Aspergillus oryzae聚为一支,但与黄曲霉的亲缘关系更近;该菌株的分生孢子与黄曲霉菌株的分生孢子一致,呈球形或近球形,表面粗糙,具若干小突起,较松散分布。结论:基于扫描电镜观察和分子生物学试验结果,将该菌株鉴定为黄曲霉Aspergillus flavus。研究结果可为扁角豆芫菁的规模化养殖过程中真菌病害的防控提供参考依据。

Objective:To solve the infection of fungal diseases in the artificial feeding of Epicauta impressicornis,and to isolate and identify a fungus infecting Epicauta impressicornis.Methods:Morphological and molecular identification of the strain were carried out using scanning electron microscopy and molecular biology methods.Results:The strain sequencing results of ITS gene and BenA gene in GenBank were ITS:MT825106,BenA:MT862132;Phylogenetic tree showed that the strain formed a clade with Aspergillus flavus and Aspergillus oryzae,but it was more closely related to Aspergillus flavus.The conidia of this strain were consistent with that of Aspergillus flavus,they were spherical or nearly spherical,with rough surface,several small protrusions and loose distribution.Conclusion:Based on the results of scanning electron microscopy and molecular biological observation,the strain is identified as Aspergillus flavus.The results of the study can provide a reference for the control of fungal diseases during the large-scale cultivation of Epicauta impressicornis.