Genetic variation and population structure of the oriental fruit moth Grapholita molesta in Shanxi, a major pome fruits growing region in North China

Grapholita molesta, commonly known as the oriental fruit moth, is one of the most destructive fruit pests both in China and in other regions of the world. We examined the genetic diversity and population structures of G. molesta populations from 11 locations in a major pome fruit production region (Shanxi province) in North China using seven microsatellite markers and sequence variations in two mitochondrial genes. We found that G. molesta in the studied region exhibited high levels of genetic diversity. Among 271 individual insects examined using microsatellite markers, mean number of alleles ranged from 5.86 to 9.00 with average 8.01. Population structure analysis revealed that populations from the eleven sampling sites formed two clusters without apparent distance isolation. Cluster 1 consisted of eight populations distributed in five regions of the sampling sites, whereas Cluster 2 consisted of three populations distributed in two distant locations of the sampling sites. Genetic exchange analysis revealed that about half of the haplotypes were shared among over 90% individual insects from different regions. Our results indicated that the population structure and genetic exchange of G. molesta in the studied region might have been affected by limited dispersal ability of the insect, environmental condition, colonization history and human-mediated dispersal. These findings should provide useful information for the implementation of area-wide pest management and for further characterization of genetic variation and population structure of this economically important pest. (C) 2016 Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society. Published by Elsevier B.V. All rights reserved.