Amplified fragment length polymorphism analysis of different geographic populations of the gypsy moth, Lymantria dispar (Lepidoptera: Lymantriidae)

Abstract
The gypsy moth, Lymantria dispar Linnaeus, is one of the most serious insect pests of palaearctic and nearctic hardwood forests. We used amplified fragment length polymorphism (AFLP) to detect genetic diversity within and among gypsy moth populations. Five AFLP primer combinations were used on 98 L. dispar samples from different parts of Europe, Asia and North America, detecting a total of 481 polymorphic and 58 monomorphic fragments. Genetic similarities based on these data were calculated and cluster analysis was performed to graphically display groupings between isolates. Lymantria dispar individuals from close geographical areas of Europe were mostly grouped together in cluster analysis resulting in the formation of subgroups corresponding to the origin of the samples. Supporting this observation, clustering of individuals from 22 neighbouring populations in southern Germany agreed well with the region they originated from. Thus, AFLP analysis revealed the existence of a certain degree of genetic variability between European gypsy moth populations that could be explained by the accumulation of polymorphisms resulting from both historical population bottlenecks and the adaptation to different environmental conditions. The results of this study therefore demonstrate that AFLP analysis is a sensitive technique for distinguishing genotypes from different geographic origins as well as from neighbouring local populations and provides sufficient molecular markers for future characterization of the gypsy moth genome.