RESUMEN
Sitobion miscanthi, the main species of wheat aphids, is one kind of harmful pest. Chemical insecticides are the important agrochemical products to effectively control wheat aphids. However, the broad application has led to serious resistance of pests to several insecticides, and understanding insecticide resistance mechanisms is critical for integrated pest management. In this study, SmUGGT1, a new uridine diphosphate (UDP)-glycosyltransferase (UGT) gene, was cloned and more strongly expressed in the SM-R (the resistant strain to imidacloprid) than in the SM-S (the susceptible strain to imidacloprid). The increased susceptibility to imidacloprid was observed after silencing SmUGGT1, indicating that it can be related to the resistance to imidacloprid. Subsequently, SmUGGT1 regulated post-transcriptionally in the coding sequences (CDs) by miR-81 was verified and involved in the resistance to imidacloprid in S. miscanthi. This finding is crucial in the roles of UGT involved in insecticide resistance management in pests.
Asunto(s)
Áfidos , Resistencia a los Insecticidas , Insecticidas , Neonicotinoides , Nitrocompuestos , Nitrocompuestos/farmacología , Neonicotinoides/farmacología , Insecticidas/farmacología , Animales , Resistencia a los Insecticidas/genética , Áfidos/genética , Áfidos/efectos de los fármacos , Triticum/genética , Triticum/metabolismo , Triticum/parasitología , Triticum/enzimología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
The wheat aphid Sitobion miscanthi is a dominant and destructive pest in agricultural production. Insecticides are the main substances used for effective control of wheat aphids. However, their extensive application has caused severe resistance of wheat aphids to some insecticides; therefore, exploring resistance mechanisms is essential for wheat aphid management. In the present study, CYP6CY2, a new P450 gene, was isolated and overexpressed in the imidacloprid-resistant strain (SM-R) compared to the imidacloprid-susceptible strain (SM-S). The increased sensitivity of S. miscanthi to imidacloprid after knockdown of CYP6CY2 indicates that it could be associated with imidacloprid resistance. Subsequently, the posttranscriptional regulation of CYP6CY2 in the 3' UTR by miR-3037 was confirmed, and CYP6CY2 participated in imidacloprid resistance. This finding is critical for determining the role of P450 in relation to the resistance of S. miscanthi to imidacloprid. It is of great significance to understand this regulatory mechanism of P450 expression in the resistance of S. miscanthi to neonicotinoids.
Asunto(s)
Áfidos , Sistema Enzimático del Citocromo P-450 , Resistencia a los Insecticidas , Insecticidas , MicroARNs , Neonicotinoides , Nitrocompuestos , Neonicotinoides/farmacología , Nitrocompuestos/farmacología , Animales , Insecticidas/farmacología , Resistencia a los Insecticidas/genética , Áfidos/genética , Áfidos/efectos de los fármacos , MicroARNs/genética , MicroARNs/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Imidazoles/farmacologíaRESUMEN
Imidacloprid is a neonicotinoid insecticide that efficiently controls piercing-sucking mouthparts pests. However, the impact of low lethal concentration of imidacloprid on key demographic parameters of wheat aphids, Schizaphis graminum (R.) and Rhopalosiphum padi (L.) has been scarcely studied. In this study, we used the age stage, two-sex life table approach to investigate the sublethal effects of imidacloprid on the biological traits of S. graminum and R. padi. Bioassays showed that imidacloprid possesses high toxicity to adult S. graminum and R. padi, with LC50 of 3.59 and 13.78 mg L-1 following 24 h exposure. A low lethal concentration of imidacloprid (LC25) significantly decreased adult longevity and total longevity of progeny generation aphids (F1) of S. graminum. Nevertheless, imidacloprid (LC25) had no significant effects on the fecundity and longevity of directly exposed parental parental S. graminum and R. padi (F0). Our results showed that the low lethal concentration of imidacloprid affected the demographic parameters that ultimately impact on the population of S. graminum. This study provides detailed information about the overall effects of imidacloprid on S. graminum and R. padi that might help to manage these two key pests.