Abstract: 【Aim】 This study aims to examine the genetic diversity and genetic differentiation of geographical populations of Adelphocoris nigritylus in North China based on the mitochondrial gene sequence. 【Methods】 A total of 233 adults from 12 geographical populations of A. nigritylus in North China were collected and used to amplify the fragments of the mitochondrial genes ND5, ND4, and Cytb by PCR. The software of MEGA, DnaSP and Arlequin were used to analyze the genetic diversity, genetic differentiation and molecular variation of A. nigritylus populations. 【Results】 The concatenated sequence of the mitochondrial genes ND5, ND4, and Cytb of A. nigritylus obtained in this study is 2 226 bp in length with 87 haplotypes, of which the haplotypes Hap3, Hap9 and Hap8 are shared by multiple individuals. The results of genetic diversity analysis showed that A. nigritylus populations had high haplotype diversity and low nucleotide diversity. The results of SAMOVA analysis indicated that the genetic variation mainly came from the populations within the group. The Mantel test results demonstrated that there was no significant correlation between the genetic distance and the geographical distance of A. nigritylus populations. 【Conclusion】 The total population of A. nigritylus in North China has a high level of genetic diversity, and might have experienced recent population expansion.

Key words:  Adelphocoris nigritylus; mitochondrial molecular marker, genetic diversity, genetic structure, population historical dynamics