Mitochondrial DNA analysis reveals a low nucleotide diversity of <i>Caligula japonica</i> in China

Abstract

Caligula japonica (Lepidoptera: Saturniidae), an endemic species in Eastern Asia, is not only an economically important pest to be controlled, but also a producer of expensive silk. We have
demonstrated previously the presence of a higher genetic diversity and a certain degree of genetic differentiation related to geographical distribution in C. japonica based on RAPD and ISSR markers. In
this paper, we determined the 574 bp segment of the mitochondrial cytochrome oxidase subunit I (COI) gene sequences of C. japonica in China to assess nucleotide sequence diversity (GenBank accession no.
FJ358506-FJ358517). The pairwise COI sequence identity between these samples reached 99 - 100%,showing a low nucleotide sequence diversity (Pi = 0.0035). In NJ tree, these samples were divided well
into Northern and Southern group, which was consistent with that previously reported based on RAPD and ISSR markers and suggested the genetic differentiation between them might have been occurred.
Further work is needed to define the genetic structure of different populations of C. japonica.