Population genetic diversity and genetic structure of Spodoptera exigua around the Bohai Gulf area of China based on mitochondrial DNA signatures.

The beet armyworm, Spodoptera exigua (Lepidoptera: Noctuidae), is an economically important pest that causes major losses in some main crop-producing areas of China. To control this pest effectively, it is necessary to investigate its population genetic diversity and genetic structure around the Bohai Gulf area of China. In this study, we used two mitochondrial genes, COI (578 bp) and Cytb (724 bp), to investigate its genetic diversity. We obtained 622 COI sequences and 462 Cytb sequences from 23 populations, and 28 and 73 haplotypes, respectively, were identified. Low to moderate levels of genetic diversity (COI: Hd = 0.267 ± 0.023, Pi = 0.00082 ± 0.00010; Cytb: Hd = 0.689 ± 0.018, Pi = 0.00255 ± 0.00029) for the total populations were observed. Phylogenetic