225 - Easy colonization of field strains of Culex quinquefasciatus and novel PCR assays for speciation and detection of strong organophosphate resistance

With increasing levels of insecticide resistance (IR) being reported in mosquito populations across the US, mosquito control districts are relying more on laboratory and field testing to determine pesticide susceptibility in local mosquito populations.  Common methods to identify and quantify IR, and the conduct of spray testing, require large numbers of organisms.  While some common disease vectors, such as Aedes aegypti, are easily colonized, others, such as Culex quinquefasciatus, provide challenges when rearing in the lab.  Here we present an easy protocol that does not require avian hosts or require expensive laboratory equipment. This method has been used to colonize over 10 strains of Cx. quinquefasciatus from rafts collected in Florida and Louisiana.  This has produced sufficient organisms for detailed examinations of the mechanisms involved in IR, which differ dramatically between the Aedes and Culex genera.  Two novel PCR based assays are described that have been developed to assist in detecting strong organophosphate resistance in Culex quinquefasciatus and to assist with the speciation of closely related Culex species.