D3314: Monitoring the susceptibility of south Florida whiteflies to Dinotefuran, Flupyradifurone, Cyantraniliprole, and Afidopyropen.

Bemisia tabaci MEAM1 damages numerous specialized vegetable crops cultivated in south Florida where the market is worth billions of dollars. MEAM1 populations have become tolerant to a variety of pesticide groups globally due to the heavy reliance on insecticides. Monitoring the tolerance of MEAM1 populations and maintaining baseline susceptibility data are essential for preserving the long-term efficacy of insecticides. Fourteen field populations of MEAM1 collected in south Florida were tested for tolerance against important groups of insecticides via serial dilution bioassays. The active ingredients tested included dinotefuran, flupyradifurone, cyantraniliprole, and afidopyropen. To quantify tolerance levels, resistance ratios (RR) and LC50s were generated. The responses of field populations were compared with a known susceptible MEAM1 colony reared in laboratory. Overall findings show that all field-collected populations were susceptible to dinotefuran (1.89 – 8.85 RR) and flupyradifurone (3.97 – 9.25 RR). Seventy-five percent of the populations tested were susceptible to afidopyropene (2.63 – 12.39 RR), whereas the remaining populations exhibited moderate tolerance (64.52 – 70.21 RR). In contrast, most of the populations tested (88.89%) exhibited moderate to high tolerance cyantraniliprole (31.02 – 120.41 RR). The two populations that exhibited moderate tolerance to afidopyropene also exhibited moderate or high tolerance to cyantraniliprole. This study has found early signs of tolerance to afidopyropene among MEAM1 populations tested. Our results emphasize the necessity of studying cross-resistance between afidopyropene and cyantraniliprole. Data generated from this study should have value in refining insecticide resistance management programs in Florida.