Abstract:  The objective of this research is to analyze the diversity of Wolbachia in insects by using nested PCR-DGGE. Samples of Anagrus nilaparvatae, one of dominant egg parasitoids of rice planthoppers in Asian rice growth area, were collected from Hangzhou, China and the Philippines. After the total DNA was extracted, the 16S rDNA and wsp gene fragments of Wolbachia were amplified with nested PCR, and then analyzed using DGGE. The results showed that Wolbachia in A. nilaparvatae were sensitively and exactly detected based on 16S rDNA gene, and the dominant bacteria in A. nilaparvatae were Acinetobacter sp., Methylophilus sp., Acidovorax sp., Burkholderia sp. and Wolbachia sp. The analysis of wsp gene showed that Wolbachia in A. nilaparvatae from Hangzhou belongs to group A, sub-group Mors, and that from the Philippines belongs to group A, sub-group Dro. The results suggest that nested PCR-DGGE is an effective molecular tool for detecting the diversity of Wolbachia in Anagrus sp., and the 16S rDNA gene fragment is the optimal biomarker for Wolbachia detection, while the wsp gene is the optimal biomarker for Wolbachia species identification and classification.

Key words: Anagrus nilaparvatae; Wolbachia, diversity, 16S rDNA gene, wsp gene, PCR-DGGE