Electrical penetration analysis of feeding by western flower thrips (Frankliniella occidentalis) on tomatoes systemically treated with cyantraniliprole

The western flower thrips is a serious pest of multiple crops worldwide causing severe damage through direct feeding and transmission of tospoviruses, including tomato spotted wilt virus. The anthranilic diamide insecticide cyantraniliprole has been shown to alter feeding behavior of F. occidentalis and F. fusca on pepper.  Herein we report on the feeding behavior of adult F. occidentalis on cyantraniliprole and imidacloprid and water treated tomato plants at two post-treatment intervals as measured by electrical penetration graphing. The first three hours of each recording were analyzed to quantify the number and duration of probing and ingestion events. The mean number of probes and the total time spent probing over the 3 hour recording period were significantly less on cyantraniliprole- treated than on water-treated plants at 10 days but not at 2-days after treatment. The imidacloprid treatment significantly reduced these feeding parameters relative to the water-treated plants at both 2 and 10 days after treatment. Cyantraniliprole did not have a significant effect on ingestion by F. occidentalis at 2 days after treatment, as measured by the number of probes that include ingestion and the total duration of ingestion. At 10 days after treatment both of these ingestion parameters were significantly reduced on cyantraniliprole-treated relative to water-treated plants. The number of probes that included ingestion was significantly less on imidacloprid-treated than on cyantraniliprole-treated plants at both 2 and 10 days after treatment but total duration of ingestion was significantly shorter on imidacloprid- than on cyantraniliprole-treated plants only at 2 days after treatment.