Meeting Abstract
Managing invasive pests requires a thorough understanding of their basic biology including life history traits, resistance to control treatments (e.g. pesticides), and thermal tolerance. Cold hardiness – ability to cope with low temperature stress – is a key mediator of insect geographic distribution and population structure and influences their ability to invade and establish in novel environments. Variation in cold hardiness within and among populations is driven by complex interactions between environmental and genetic factors and is regulated by multiple physiological and molecular mechanisms. The aim of this study is to leverage genetic variation across genetically distinct lineages of a globally invasive fruit pest, spotted wing drosophila (SWD; Drosophila suzukii), to identify key transcriptional regulators of cold hardiness. First discovered in CA in 2008, SWD has since spread to all 48 mainland states. Female SWD lay their eggs into ripening, soft-skinned fruits of economic importance, and subsequent larval feeding leads to product loss. We have generated isogenic SWD lineages derived from field populations along a North-South latitudinal gradient from Wisconsin to Florida. We measured acute cold shock survival, cold-induced deficits in fecundity, and critical thermal minimum temperature (CTmin) across all lineages. Current findings indicate significant variation among lineages for all cold hardiness measures assayed. In ongoing experiments, we will identify key transcriptional regulators of cold hardiness via RNA-seq. Results of this study will provide greater insights into the genetic mechanisms underlying variation in invasion-related traits in SWD and will contribute to improved modeling and control efforts.
