螺旋粉虱成虫体内细菌群落多样性的PCR-DGGE 和16S rRNA文库序列分析

为了解螺旋粉虱Aleurodicus dispersus体内细菌多样性和主要优势菌群结构, 用PCR-DGGE和16S rRNA文库对采自于海南省番石榴上螺旋粉虱雌、 雄成虫体内的细菌群落进行了分析。用PCR扩增体内细菌16S rRNA基因, 构建雌、 雄虫克隆文库; 再用限制性片段长度多态性（restriction fragment length polymorphism, RFLP）方法从文库中筛选不同16S rRNA基因图谱, 根据图谱对克隆子进行分型。从螺旋粉虱雌、 雄两个样品中共获得10 种分类操作单元(operational taxonomic unit, OTUs)。以16S rRNA基因为基础构建系统发育树, 系统发育分析表明, 螺旋粉虱雌、 雄成虫体内优势菌群主要为发酵菌属Zymobacter, 杀雄菌属Arsenophonus, 泛菌属Pantoea和假单胞菌属Pseudomonas。Candidatus Portiera aleyrodidarum和Arsenophonus sp.可能为其体内共生菌群, 在所有样品中均可稳定地检测到。这些微生物可能对螺旋粉虱生长发育、 繁殖和性比调控起到重要的协同作用。     

Irradiation effect on the structure of bacterial communities associated with the oriental fruit fly,Bactrocera dorsalis

The role of symbiotic microbes in insects, especially the beneficial character of this interaction for insects, has received much attention in recent years as it has been related to important aspects of the host insects' biology such as development, reproduction, survival, and fitness. Among insect hosts, tephritid fruit flies are well known to form beneficial associations with their symbionts. To control these destructive agricultural pests, environmentally friendly approaches, like the sterile insect technique as a component of integrated pest management strategies, remain most effective. In this study, changes in the bacterial profile of mass‐reared oriental fruit flies, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), were examined in both larval and adult stages and also after irradiation by employing a 16S rRNA gene‐based Illumina sequencing approach. Proteobacteria was the prevalent bacterial phylum in non‐irradiated adults and larvae. Alphaproteobacteria was the most abundant class in larvae but almost absent in adults, which was dominated by Gammaproteobacteria. Firmicutes were present in both developmental stages but at lower relative abundance. At genus level, Acetobacter prevailed in the larval stage and members of the Enterobacteriaceae family in adults. Irradiated samples exhibited higher diversity and richness indices compared to the non‐irradiated oriental fruit flies, whereas no significant changes were observed between the two developmental stages of the non‐irradiated samples. Lactobacillus, members of the Orbacecae family, and Morganella were detected but to a lesser degree upon irradiation, whereas the relative abundance of Lactococcus and Orbus increased. The bacterial profile of larvae appeared to be different compared to that of adult B. dorsalis flies. The subsequent application of irradiation at the pupal stage led to the development of different microbiota between treated and untreated samples, affecting diversity and operational taxonomic unit composition. Irradiated samples of oriental fruit flies were characterized by higher species diversity and richness.