Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/14/2015
Publication Date: 2/11/2016
Publication URL: http://handle.nal.usda.gov/10113/61879
Citation: Parys, K.A., Snodgrass, G.L., Luttrell, R.G., Allen, K.C., Little, N. 2016. Baseline susceptibility of Lygus lineolaris (Hemiptera:Miridae) to novaluron. Journal of Economic Entomology. 109(1):339-344;doi:10.1093/jee/tov318.
Interpretive Summary: Tarnished plant bug populations were collected from the Mississippi River Delta of Arkansas, Louisiana, and Mississippi, and screened for susceptibility to the insecticide novaluron. Two different bioassays were used to evaluate susceptibility, and in 2013 both types of assays were run on several colonies in order to compare the methods. Susceptibility of populations using both methods was compared to insects collected from a location with a historically susceptible population. Results from the bioassays indicated that there was significant variability in susceptibility to the insecticide across the landscape, and populations from some locations were more susceptible to the insecticide than those from the historically susceptible population.
Technical Abstract: Tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), populations were collected from field locations in the Mississippi River Delta of Arkansas, Louisiana, and Mississippi. Third instar F1 nymphs from each field location, in addition to a laboratory colony, were screened for susceptibility to novaluron. Both a glass vial bioassay and a diet-incorporated bioassay used dose-response regression lines to calculate LC50 and LC90 values for novaluron. Mean LC50s for glass vial bioassays ranged from 44.70 ± 3.58 to 66.54 ± 4.19 µg/vial, while mean LC50s for diet-incorporated bioassays ranged from 12.10 ± 0.77 to 17.63 ± 2.42 µg/200 ml of artificial diet. A comparison of LC50 values from the same field population screened using both bioassay methods failed to show a relationship. LC50 values from field locations were compared to a historically susceptible population from Crossett, Arkansas. Results indicated that considerable variability in susceptibility to novaluron exists within field populations of tarnished plant bugs across the Delta, including some locations with lower LC50 values than a historically susceptible population.