flupyradifurone and cyantraniliprole

Neonicotinoids have been among the most widely and abundantly used insecticides for most of the current century. The effects of these substances on nontarget terrestrial and aquatic organisms have resulted in a significant decrease in their use in many parts of the world. In response, the application of several novel classes of insecticides including diamides, ketoenols, pyridines, and butenolides has significantly increased. The hexapod subclass Collembola is an ecologically significant and widely distributed group of soil invertebrates often found in leaf litter and in surficial soils. We exposed the parthenogenic collembolan species Folsomia candida to six insecticides in a sandy loam soil for 28 days, including two neonicotinoids (thiamethoxam and clothianidin), a diamide (cyantraniliprole), a ketoenol (spirotetramat), a pyridine (flonicamid), and a butanolide (flupyradifurone) to assess the effect of each insecticide on survival and reproduction. Clothianidin, thiamethoxam, and cyantraniliprole (median effective concentration [EC50] values for reproduction: 0.19, 0.38, and 0.49 mg/kg soil, respectively) had a greater effect on survival and reproduction of F. candida than flupyradifurone, spirotetramat, and flonicamid (EC50 values for reproduction: 0.73, >3.08, and 5.20 mg/kg soil, respectively). All significant impacts found in our study were observed at concentrations below concentrations of the active ingredients that would be expected in agricultural soils. Environ Toxicol Chem 2023;42:1516-1528. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Topics: Animals; Arthropods; Insecticides; Neonicotinoids; Reproduction; Soil; Thiamethoxam

Cucurbit yellow stunting disorder virus (CYSDV) is a whitefly-transmitted Crinivirus (Closteroviridae) that impacts melon production in many parts of the world including the USA. It has been responsible for melon crop loss in the southwestern U.S. since 2006 when it was first identified. Control strategies have revolved mainly around chemical control, but research to identify suitable products and approaches to implementing them have lagged. The current study investigated the performance of four systemic insecticides in the field while concurrently tracking CYSDV disease progression after controlled and natural whitefly inoculation of young melon plants. Assessments of virus incidence were made using two different visual observation methods in concert with ELISA analyses of leaf disks samples collected biweekly. Infection rates were consistently lowest in plots treated with the butenolide insecticide flupyradifurone while dinotefuran was second in efficacy measures. Flupyradifurone also held whitefly densities to their lowest numbers relative to the other treatments. Two other insecticides, imidacloprid and cyantraniliprole, exacerbated virus incidence in multiple trials. Further investigation into the anomalous finding of increased virus incidence due to insecticide application is ongoing.

Topics: 4-Butyrolactone; Animals; Crinivirus; Cucurbitaceae; Guanidines; Hemiptera; Insect Vectors; Insecticides; Neonicotinoids; Nitro Compounds; ortho-Aminobenzoates; Plant Diseases; Pyrazoles; Pyridines