Neonicotinoid Resistance in Tobacco Thrips: 2014 Survey Results from the Midsouth and Southeast Cotton Production Areas

In response to reports of variable effectiveness of neonicotinoid seed treatment in controlling thrips on cotton at some locations during 2013, tobacco thrips (Frankliniella fusca) were collected from seedling cotton or surrounding vegetation at 55 locations across the southeast and midsouth cotton production areas  during 2014.  These thrips were subjected to a diet-based, diagnostic dose bioassay developed to identify populations that were significantly less susceptible to thiamethoxam and imidacloprid than a reference laboratory population known to be highly susceptible to neonicotinoid insecticides.  Populations displaying some level of resistance relative to the reference population were identified from  number of locations across the survey area  Detailed results from the diagnostic dose survey and follow-up dose response assays of populations identified as resistant will be presented.