title: First detection of Varroa destructor resistance to coumaphos in Argentina.
abstract: In Argentina, studies on Varroa destructor resistance to coumaphos are still unknown. At present, high infestation levels of V. destructor are being detected in colonies of Apis mellifera after treatment with this acaricide. The aim of the present study was to determine the LC50 of coumaphos in V. destructor from four apiaries with high mite density after treatment with coumaphos. The LC50's were 112, 319, 127 and 133 microg/Petri dish for mites from the four apiaries. Significant LC50 differences were detected between resistant and susceptible mites. LC50 increased 197-559-fold when compared to the corresponding baseline, suggesting the development of resistance. These results are the first report of resistance to coumaphos in V. destructor in Argentina.
authors.affiliation: Laboratorio de Artrópodos, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes, 3350, 7600, Mar del Plata, Argentina. biomaggi@gmail.com
authors.forename: Matías Daniel
authors.initials: MD
authors.lastname: Maggi
authors.forename: Sergio R
authors.initials: SR
authors.lastname: Ruffinengo
authors.forename: Natalia
authors.initials: N
authors.lastname: Damiani
authors.forename: Norma H
authors.initials: NH
authors.lastname: Sardella
authors.forename: Martín J
authors.initials: MJ
authors.lastname: Eguaras
mesh_terms: D000818:Animals; D001118:Argentina; D001516:Bees / Q000469:parasitology; D003372:Coumaphos / Q000633:toxicity*; D004351:Drug Resistance; D007928:Lethal Dose 50; D008925:Mites / Q000187:drug effects*; D010575:Pesticides / Q000633:toxicity*
chemical_list: D010575:Pesticides; D003372:Coumaphos