title: Monitoring techniques of the western corn rootworm are the precursor to effective IPM strategies.
abstract: BACKGROUND
  The western corn rootworm (WCR) is economically the most important pest of maize in Croatia. To predict WCR adult population abundance and variability, traditional, genetic and morphometric monitoring of populations was conducted over time through each phase of the WCR invasion process in Croatia.
  
  
  RESULTS
  Through traditional monitoring it was shown that WCR established their current population and reached economic densities after 14 years persisting in the study area. Regression-tree-based modelling showed that the best predictor of WCR adult abundance was the total amount of rainfall. Genetic monitoring indicated that genetic differentiation increased over time at the intrapopulation level, and morphometric monitoring indicated that wing morphotypes varied according to edaphic landscape changes.
  
  
  CONCLUSIONS
  Traditional population metric surveys are important in WCR integrated pest management (IPM), as such surveys can be effectively used to predict population abundances. Novel-use monitoring techniques such as genetics and geometric morphometrics can be used to provide valuable information on variation within and among populations. The monitoring techniques presented herein provide sound data to assist in the understanding of both WCR ecology and population genetics and may provide more information than that currently available using traditional techniques (e.g. sticky traps), and as such these additional techniques should be written into IPM for WCR.
authors.affiliation: Department for Agricultural Zoology, Faculty of Agriculture, University of Zagreb, Zagreb, Croatia.
authors.forename: Darija
authors.initials: D
authors.lastname: Lemic
authors.affiliation: Centre for Sustainable Ecosystem Solutions, University of Wollongong, Wollongong, New South Wales, Australia.
authors.forename: Katarina M
authors.initials: KM
authors.lastname: Mikac
authors.affiliation: Croatian Centre for Agriculture, Food and Rural Affairs, Institute for Plant Protection, Zagreb, Croatia.
authors.forename: Antonela
authors.initials: A
authors.lastname: Kozina
authors.affiliation: Faculty of Life Sciences, University of Manchester, Manchester, UK.|Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile.
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Benitez
authors.affiliation: Centre for Sustainable Ecosystem Solutions, University of Wollongong, Wollongong, New South Wales, Australia.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: McLean
authors.affiliation: Department for Agricultural Zoology, Faculty of Agriculture, University of Zagreb, Zagreb, Croatia.
authors.forename: Renata
authors.initials: R
authors.lastname: Bažok
mesh_terms: D000818:Animals; D001517:Coleoptera / Q000235:genetics / Q000254:growth & development*; D004784:Environmental Monitoring / Q000379:methods*; D005260:Female; D005828:Genetics, Population; D008297:Male; D008962:Models, Theoretical; D010571:Pest Control; D010935:Plant Diseases / Q000469:parasitology*; D003313:Zea mays / Q000469:parasitology*
keywords: population abundance; population genetics; regression tree; wing shape analyses