重庆地区3株球孢白僵菌的分离鉴定

我国是农业和林业大国,农林害虫的危害造成了严重的经济损失,同时化学防治也导致了环境污染等诸多问题.因此,开发基于虫生真菌的生物农药意义重大.为了丰富虫生真菌菌种资源,以野外感染白僵菌的蝽蟓及室内感染的家蚕僵虫样品为实验材料,采用多种培养基,分离获得了3株虫生真菌菌株,分别为来自蝽蟓的NB-1,PW-1菌株和来自家蚕的JCY菌株,形态学观察结果表明,各菌株的培养特征与白僵菌属菌株较为一致;分子生物学鉴定表明,各菌株rDNA ITS序列与GenBank中白僵菌属球孢白僵菌多个菌株同源性高达99%,因此将菌株NB-1,PW-1和JCY均鉴定为球孢白僵菌(Beauveria bassiana);生物学特性观察发现不同菌株间分生孢子产生量存在显著差异,分离自蝽蟓僵虫的球孢白僵菌PW-1,NB-1分生孢子产量分别为(7.55±0.15)×10~7个/mL,(6.30±0.40)×10~7个/mL,均高于家蚕分离株JCY,其产孢量仅为(3.02±0.22)×10~7个/mL.结论为后续研发针对包括草地贪夜蛾在内的农林害虫生物杀虫剂奠定了菌种基础.

Isolation and Identification of Three Beauveria bassiana Isolates in Chongqing Area

China is one of the biggest agricultural and forestry countries in the world,and agricultural and forestry pests cause serious economic losses annually. At the same time,chemical control measures have caused many problems such as environmental pollution. Therefore,the development of bioinsecticides based on entomogenous fungi is of great importance. In order to enrich the resources of entomopathogenic fungi,we obtained entomogenous fungal isolates via isolating and cultivating from wild stinkbug and silkworm infected by Beauveria sp. and identified their biological characteristics. In this experiment,three isolates (NB-1,PW-1 and JCY) were identified. Morphological observation showed that the cultural characteristics of all the three strains were consistent with those of Beauveria bassiana. ITS of each isolate shared 99% homology to many isolates of B. bassiana in GenBank. Thus,isolates NB-1,PW-1 and JCY were all identified as B. bassiana. Significant differences in conidia production were detected between different isolates via biological characteristics observation. The conidial yield of PW-1 and NB-1 isolated from the infected stinkbug was (7.55±0.15)×10⁷ and (6.30±0.40)×10⁷ spores/mL,respectively,which was higher than that of JCY isolated from the infected silkworm,(3.02±0.22)×10⁷ spores/mL.