title: Insecticide resistance in pollen beetles over 7 years - a landscape approach.
abstract: BACKGROUND
  In spite of considerable interest in the impact of pesticides on pest populations, few attempts have been made to link resistance patterns of insect pests to land-use features across spatial and temporal scales. We hypothesise that pollen beetle pesticide resistance increases in areas with a high proportion of oilseed rape and with an even mixture of winter and spring oilseed rape owing to high pesticide selection pressure in such areas.
  
  
  RESULTS
  Here, we investigated 7 years of lambda-cyhalothrin (Karate(®) ) resistance in field-collected pollen beetle adults from a total of 180 sampling points across ten regions in Sweden. We found a positive effect on pollen beetle pesticide resistance of proportion of oilseed rape and even spring-winter oilseed rape mixture. However, this was true only for the regional spatial scale. Significant land-use effects in the long-term models, with oilseed rape data averaged over a longer (4 years) period of time, suggested an effect of regional landscape history on current pest resistance.
  
  
  CONCLUSIONS
  For successful control of pollen beetle pesticide resistance, we suggest a long-term regional strategy for oilseed rape management. This land-use approach provides a framework for further investigations that integrate resistance management into landscape research.
authors.affiliation: Swedish University of Agricultural Sciences, Department of Ecology, Uppsala, Sweden.
authors.forename: Laura G A
authors.initials: LG
authors.lastname: Riggi
authors.affiliation: Swedish University of Agricultural Sciences, Department of Ecology, Uppsala, Sweden.
authors.forename: Vesna
authors.initials: V
authors.lastname: Gagic
authors.affiliation: Swedish University of Agricultural Sciences, Department of Ecology, Uppsala, Sweden.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Bommarco
authors.affiliation: Swedish University of Agricultural Sciences, Department of Ecology, Uppsala, Sweden.
authors.forename: Barbara
authors.initials: B
authors.lastname: Ekbom
mesh_terms: D000818:Animals; D001517:Coleoptera / Q000187:drug effects*; D019143:Evolution, Molecular; D007305:Insecticide Resistance / Q000235:genetics; D009570:Nitriles / Q000494:pharmacology; D011722:Pyrethrins / Q000494:pharmacology; D012641:Selection, Genetic
chemical_list: D009570:Nitriles; D011722:Pyrethrins; C037304:cyhalothrin
keywords: Brassica napus; Meligethes aeneus; lambda-cyhalothrin; landscape management; oilseed rape; pest management; pesticide resistance