Abstract: Monolepta hieroglyphica (Motschulsky) (Coleoptera: Chrysomelidae) has become more serious on maize in some maize planting areas of North China since 2001. To investigate the level of genetic diversity, genetic differentiation and gene flow among different populations and within populations of M. hieroglyphica in North China, partial sequences (484 bp) of mtDNA COⅡ (mitochondrial cytochrome oxidase subunit Ⅱ) gene in 26 geographic populations from North China were sequenced and analyzed. In the total 515 individuals, 28 variable sites and 15 haplotypes were observed. Phylogenetic tree of 15 COⅡ haplotypes exhibited two main clusters. The mean haplotype diversity of all populations was 0.257, varied from 0.100 to 0.515 within populations. The overall Fst value was 0.585, Gst was 0.417, and the average gene flow (Nm) among the 26 populations was 0.35. Molecular variance (AMOVA) analysis indicated that a high proportion of the total genetic variance was attributable to variations among populations (58.58%). The Tajima’s D neutrality test results suggest that for M. hieroglyphica in North China there might be no population expansion. These results indicate that the level of gene flow among different populations is very low,  and there is obvious differentiation among M. hieroglyphica populations in North China.

Key words: Monolepta hieroglyphica, mtDNA COⅡ, geographic population, genetic diversity, genetic differentiation