The Temporal and Spatial Invasion Genetics of the Western Corn Rootworm (Coleoptera: Chrysomelidae) in Southern Europe

PLoS One. 2015 Sep 25;10(9):e0138796. doi: 10.1371/journal.pone.0138796. eCollection 2015.

Abstract

This study describes the genetics of the western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte in southern Europe during the introduction (1996-2001) and establishment/spread (2002-2011) phases of its invasion. The Diabrotica microsatellite core-set was used to perform traditional population genetics analyses. Our results indicated that during the introduction phase genetic diversity and population genetic structure were lower overall as compared to the establishment/spread phase. Unusually high genetic differentiation was found between the Italy and southern Europe comparisons, including high differentiation between Italian populations separated by a short distance during the establishment/spread phase. STRUCTURE analysis revealed two genetic clusters during the introduction phase and two genetic clusters during the establishment/spread phase. However, bottlenecked populations were only detected during the invasion phase. A small but significant isolation by distance effect was noted in both phases. Serbia was the geographic source of WCR to Croatia and Hungary in the introduction phase, while the United States of America was the possible source of WCR to Italy in 2001. These introductory populations were the subsequent source of individuals sampled during the establishment/spread phase. Repeated introductions and admixture events in southern Europe may have resulted in genetically diverse WCR populations that have attained 83% of all known alleles worldwide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Coleoptera / genetics*
  • Coleoptera / physiology
  • Europe
  • Evolution, Molecular
  • Genes, Insect
  • Genetic Variation*
  • Genetics, Population
  • Introduced Species
  • Microsatellite Repeats*
  • Phylogeography
  • Population Dynamics
  • Zea mays / parasitology*

Grants and funding

This research was supported by the Ministry of Science, Education and Sports of the Republic of Croatia by projects: Risk estimation system- the basis for integrated control of corn pests, principal investigator: prof.dr.sc. Renata Bažok 178-1782066-2064. The spatial distribution of economically important pests with the use of GIS, Principal investigator: prof.dr.sc. Jasminka Igrc Barčić 178-1782066-2065.