Effects of Wolbachia on mitochondrial DNA variation in populations of Athetis lepigone (Lepidoptera: Noctuidae) in China

Abstract

Wolbachia are endosymbiotic bacteria that infect arthropods and incompatibility among strains can affect gene flow within host insect populations that can significantly result in host mitochondrial DNA (MtDNA) variation within or among populations. The effects of Wolbachia infection on Athetis lepigone MtDNA variation were studied across 12 geographical populations sampled from North China. Mitochondrial COI gene and Wolbachia wsp gene were both obtained from 423 individuals, including 46 Wolbachia infected and 377 uninfected individuals. Average A. lepigone infection rate was 11% (range: 0 to 26%), and wsp sequence variation defined three distinct Wolbachia strains; wLep1, wLep2, and wLep3, respectively. A haplotype network showed no relationship between A. lepigone MtDNA haplotype and Wolbachia infection. Furthermore, haplotype variation mainly exists within populations, although the proportion of variation is higher within uninfected compared to infected individuals. The lack of correlation between A. lepigone haplotype and Wolbachia strain, suggests symbiont infection may not affect mating compatibility or gene flow within host populations in China.