title: Neonicotinoid-Coated Zea mays Seeds Indirectly Affect Honeybee Performance and Pathogen Susceptibility in Field Trials.
abstract: Thirty-two honeybee (Apis mellifera) colonies were studied in order to detect and measure potential in vivo effects of neonicotinoid pesticides used in cornfields (Zea mays spp) on honeybee health. Honeybee colonies were randomly split on four different agricultural cornfield areas located near Quebec City, Canada. Two locations contained cornfields treated with a seed-coated systemic neonicotinoid insecticide while the two others were organic cornfields used as control treatments. Hives were extensively monitored for their performance and health traits over a period of two years. Honeybee viruses (brood queen cell virus BQCV, deformed wing virus DWV, and Israeli acute paralysis virus IAPV) and the brain specific expression of a biomarker of host physiological stress, the Acetylcholinesterase gene AChE, were investigated using RT-qPCR. Liquid chromatography-mass spectrometry (LC-MS) was performed to detect pesticide residues in adult bees, honey, pollen, and corn flowers collected from the studied hives in each location. In addition, general hive conditions were assessed by monitoring colony weight and brood development. Neonicotinoids were only identified in corn flowers at low concentrations. However, honeybee colonies located in neonicotinoid treated cornfields expressed significantly higher pathogen infection than those located in untreated cornfields. AChE levels showed elevated levels among honeybees that collected corn pollen from treated fields. Positive correlations were recorded between pathogens and the treated locations. Our data suggests that neonicotinoids indirectly weaken honeybee health by inducing physiological stress and increasing pathogen loads.
authors.affiliation: Université Laval, Institut de Biologie Intégrative et des Systèmes (IBIS), Québec, Canada; Centre de Recherche en Sciences Animales de Deschambault (CRSAD), Québec, Canada.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Alburaki
authors.affiliation: Université Laval, Institut de Biologie Intégrative et des Systèmes (IBIS), Québec, Canada.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Boutin
authors.affiliation: Université Laval, Institut de Biologie Intégrative et des Systèmes (IBIS), Québec, Canada; Centre de Recherche en Sciences Animales de Deschambault (CRSAD), Québec, Canada.
authors.forename: Pierre-Luc
authors.initials: PL
authors.lastname: Mercier
authors.affiliation: CNRS, Laboratoire Evolution, Génomes et Spéciation LEGS, Gif-sur-Yvette, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Loublier
authors.affiliation: Université du Québec à Montréal, Québec, Canada.
authors.forename: Madeleine
authors.initials: M
authors.lastname: Chagnon
authors.affiliation: Université Laval, Institut de Biologie Intégrative et des Systèmes (IBIS), Québec, Canada; Université Laval, Département de biologie, Faculté des sciences et de génie, Québec, Canada.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Derome
mesh_terms: D000110:Acetylcholinesterase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001516:Bees / Q000187:drug effects* / Q000469:parasitology / Q000821:virology*; D004198:Disease Susceptibility; D035264:Flowers / Q000737:chemistry / Q000633:toxicity; D017344:Genes, Insect / Q000187:drug effects; D058871:Organic Agriculture; D010573:Pesticide Residues / Q000032:analysis / Q000633:toxicity; D010575:Pesticides / Q000032:analysis / Q000633:toxicity*; D011058:Pollen / Q000737:chemistry / Q000633:toxicity; D012639:Seeds / Q000737:chemistry / Q000633:toxicity; D013312:Stress, Physiological / Q000187:drug effects; D057077:Varroidae / Q000472:pathogenicity; D003313:Zea mays / Q000737:chemistry / Q000633:toxicity
chemical_list: D010573:Pesticide Residues; D010575:Pesticides; D000110:Acetylcholinesterase