不同生境烟粉虱体内共生菌的检测及其对寄主生物学特性的影响

Detection of Endosymbionts in Different Bemsia tabaci Populations and Their Effects on Whitefly Host

摘要: 烟粉虱Bemisia tabaci是一种世界性分布的农业害虫。本文利用PCR扩增和DNA测序技术，研究了野生和实验室饲养的烟粉虱B型和Q型种群内共生菌的感染情况；并利用利福平对Q型烟粉虱实验室种群体内的共生菌进行了灭活处理，就处理前后烟粉虱的生物学特性变化进行比较。研究结果表明，所检测的的烟粉虱种群中均有初生共生菌Candidatus Portiera aleyrodidarum的感染，而次生共生菌Wolbachia和杀雄菌Arsenophonus在不同生境下的烟粉虱种群内，其感染率存在较大差异。利用1.0 mg/ml的利福平对饲养型的Q型烟粉虱成虫进行处理，48 h后处理样本体内Wolbachia的感染检测为阴性，而初生共生菌Candidatus和杀雄菌Arsenophonus仍为阳性。共生菌灭活处理后，烟粉虱成虫单雌产卵量明显下降，由36.9粒/头下降至26.4粒/头；F1代的发育历期延长，F1代种群中雄性比例有较大幅度增加，由对照种群中的45.28%上升至58.06%。本文研究表明，不同生境下，烟粉虱体内的共生菌类群存在差异，次生共生菌Wolbachia对烟粉虱的发育、繁殖及种群性比等方面有着明显的影响。

Abstract: The sweetpotato whitefly Bemisia tabaci (Gennadius) is a globally distributed agricultural pest. The species and infection rates of different endosymbionts in field and laboratory populations of B. tabaci B and Q biotyes were detected by molecular methods. Meawhile, the endosymbionts in B. tabaci Q biotype lab population were inactivated with rifampicin, and then the biology of Wolbachia positive and negative popula-tions of B. tabaci Q biotype were compared. Rusults indicated that all the populations of B. tabaci were in-fected by the primary endosymbiont Candidatus Portiera aleyrodidarum, regardless biotype or population habitat of field or lab, while the infection of secondary endosymbionts Wolbachia and Arsenophonus were marked different in various B. tabaci populations related to biotype and habitat. Inactivated with 1.0mg/ml rifampicin for 48 h, the infection of Wolbachia in B. tabaci Q biotype was completely eliminated, but no ob-vious effect on the Candidatus and Arsenophonu in all the whitefly popualtions. Treated by rifampicin, the fecundity of female adults reduced and the developmental time of F1 offspring extended. Results also showed that the elimination of Wolbachia in B. tabaci led to the increase of male progeny proportion. In general, our current study showed that endosymbionts varied in different B. tabaci populations from various habitats and Wolbachia has significant effects on the biology of its whitefly hosts.