Cold tolerance of non-cold acclimated spotted wing drosophila (Diptera:Drosophilidae)

Drosophila suzukii Matsumura is an invasive insect pest which was discovered in North America in 2008 and can cause extensive damage to ripe and ripening soft-skinned fruits. Since then, the insect has spread through much of North America, including in soft-skinned fruit crops in Minnesota since 2012.  Northerly limits to the geographic range of invasive insects in North America can be estimated by measuring their cold tolerance. Three key cold tolerance parameters were measured to gauge the ability of D. suzukii to overwinter in cold climes. The supercooling point, lower lethal time, and lower lethal temperature were measured for adult summer morph D. suzukii.  Cold tolerance results of summer morph flies (reared at 25˚C with a photoperiod of 16:8 [L:D] h) are compared to preliminary measures of winter morph flies (reared at 10˚C with a photoperiod of 12:12 [L:D] h).