我国烟粉虱自然种群中存在广泛的Wolbachia感染现象

Wolbachia extensively harbored by Bemisia tabaci in China

Wolbachia是广泛分布于节肢动物生殖组织中的细胞质遗传的一类共生菌,可以引起宿主生殖行为的改变。烟粉虱是重要的农业害虫,已有的研究表明烟粉虱中存在Wolbachia的感染,但所检测到的感染率不高,并且迄今在烟粉虱中所检出的Wolbachia均属于B组群。该研究从我国河北、新疆、北京、山东、浙江、广西、海南、广州和福建采集到18个烟粉虱地理种群,首先基于ITS1 rDNA克隆测序鉴定了烟粉虱的生物型,然后采用自行设计的Wolbachia 16S rDNA及wsp基因的专用引物对所采集到的烟粉虱种群进行了分子检测。结果表明几乎所有的烟粉虱自然种群中都存在Wolbachia感染,同时还发现B/Q生物型烟粉虱中主要感染A组群Wolbachia,而非B/Q生物型烟粉虱中存在大量的超感染现象。该研究显示烟粉虱自然种群中Wolbachia的感染率比预想的要高得多,而分子检测方法的灵敏度可能是影响Wolbachia感染率研究的关键因素之一。

Wolbachia are a group of maternally inherited bacteria harbored by a variety of arthropods and can ma- nipulate the reproductivity of their hosts. Eighteen populations of whiteflies were collected from Hebei, Xinjiang, Beijing, Shandong, Zhejiang, Guangxi, Hainan, Guangzhou and Fujian provinces, China. These whiteflies were molecularly identified using internal transcribed spacer 1 ITS1 rDNA sequences. They were then detected for Wolbachia infection using Wolbachia-specific primers designed based on 16S rDNA and wsp gene sequences. The results showed that almost all populations were detected positive for Wolbachia infection. Whiteflies of B / Q group mainly carried Wolbachia belonging to supergroup A, while non-B / Q whiteflies were commonly detected for Wolbachia superinfection. This study indicated that the infection rate of Wolbachia in natural populations of B. tabaci might be much higher than expected, and the threshold of detection methods may be one of the key factors influencing detection of Wolbachia infection.