RESUMEN
Imidacloprid has been used to control one of most serious pests, Bemisia tabaci. However, B. tabaci has developed imidacloprid resistance mainly by over-expressing CYP6CM1. It was reported that imidacloprid-resistant B. tabaci showed no or low level of cross-resistance against dinotefuran. Here, we expressed CYP6CM1 variants using Sf9/baculovirus and/or Drosophila S2 cells and showed that CYP6CM1 variants metabolized imidacloprid but not dinotefuran. In addition, we demonstrated that imidacloprid and pymetrozine competed for a CYP6CM1 variant more efficiently than dinotefuran, using a luminescent substrate competition assay. These results suggest that lack of metabolic activity of CYP6CM1 variants against dinotefuran caused no or low level of cross-resistance.
Asunto(s)
Guanidinas/metabolismo , Guanidinas/farmacología , Hemípteros/efectos de los fármacos , Hemípteros/metabolismo , Insecticidas/metabolismo , Insecticidas/farmacología , Neonicotinoides/metabolismo , Neonicotinoides/farmacología , Nitrocompuestos/metabolismo , Nitrocompuestos/farmacología , Animales , Hemípteros/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Resistencia a los Insecticidas/genética , Triazinas/metabolismo , Triazinas/farmacologíaRESUMEN
BACKGROUND: Pyridazine pyrazolecarboxamides (PPCs) are a novel insecticide class discovered and optimized at BASF. Dimpropyridaz is the first PPC to be submitted for registration and controls many aphid species as well as whiteflies and other piercing-sucking insects. RESULTS: Dimpropyridaz and other tertiary amide PPCs are proinsecticides that are converted in vivo into secondary amide active forms by N-dealkylation. Active secondary amide metabolites of PPCs potently inhibit the function of insect chordotonal neurons. Unlike Group 9 and 29 insecticides, which hyperactivate chordotonal neurons and increase Ca2+ levels, active metabolites of PPCs silence chordotonal neurons and decrease intracellular Ca2+ levels. Whereas the effects of Group 9 and 29 insecticides require TRPV (Transient Receptor Potential Vanilloid) channels, PPCs act in a TRPV-independent fashion, without compromising cellular responses to Group 9 and 29 insecticides, placing the molecular PPC target upstream of TRPVs. CONCLUSIONS: PPCs are a new class of chordotonal organ modulator insecticide for control of piercing-sucking pests. Dimpropyridaz is a PPC proinsecticide that is activated in target insects to secondary amide forms that inhibit the firing of chordotonal organs. The inhibition occurs at a site upstream of TRPVs and is TRPV-independent, providing a novel mode of action for resistance management. © 2023 BASF Corporation. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Asunto(s)
Áfidos , Insecticidas , Animales , Insecticidas/farmacología , Insectos , Amidas/farmacología , Resistencia a los InsecticidasRESUMEN
This study adopted a person-organization fit framework to examine (a) whether employees' perceptions of organizational strategy for adaptation predicted their commitment to their organization and their intentions to stay and (b) whether these 2 relationships were moderated by perceived job alternatives. Support was found for both hypotheses. Specifically, when there are numerous perceived job alternatives, employees who perceive a misfit between their company's strategy and their preferred strategy were less committed to their organization and less likely to stay than their fit counterparts.