engleski

Genetic structure, gene flow and dispersal patterns of western corn rootworm Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) populations from Croatia

The WCR is a highly invasive pest of maize. It was introduced to Europe in the early 1990s from the USA and now is a serious pest in Europe, including Croatia. Understanding levels of genetic variability of introduced populations is important for investigating the adaptive potential of such populations in their new invaded environments. At the moment there is a little detailed knowledge of the population genetics of WCR in Croatia, or an understanding of the reasons for their invasion success. This study aims to investigate the genetic structure, gene flow and dispersal of WCR populations from Croatia by using the already established WCR ‘core set’ of six microsatellite markers. Samples of WCR (15-30 individuals) were collected at 15 sites located in eastern and central Croatia. After DNA extraction individuals were genotyped using an ABI3130xl Genetic Analyzer following methods of Kim et al. (2008). To investigate the genetic structure, gene flow and dispersal of WCR populations we report on: 1) tests of fit to Hardy-Weinberg equilibrium (HWE) ; 2) per locus estimates of: number of alleles, expected (HE) & observed (HO) heterozygosity, Weir and Cockerham’s (1984) FIS (inbreeding co-efficient) & θ (or FST) ; and 4) overall loci and populations estimates of θ. Using a Mantel test (correlation of FST (1/ FST -1) & Ln of geographic distance (km) among population pairs) we will examine whether the WCR gene flow patterns detected can be described under and isolation by distance model. Finally, evidence for recent bottlenecks will be assessed using the program Bottleneck 1.2. under the two phase model (TPM) and the step wise mutation model (SMM) suitable for microsatellites.

genetic variability; invasive pest; invasion success; maize; microsatellite markers; population genetics; western corn rootworm

nije evidentirano