Laboratory selection, resistance risk assessment, multi‐resistance, and management of Tetranychus urticae Koch to bifenthrin, bifenazate and cyflumetofen on cowpea

Abstract

BACKGROUND Tetranychus urticae (T. urticae) Koch is an important pest of vegetable crops worldwide. In this study, bioassays were carried out to analyze the resistance risk, multi‐resistance and management of T. urticae Koch to bifenthrin, bifenazate and cyflumetofen on cowpea. RESULTS The resistance ratios of the adult T. urticae population to bifenthrin (G16), bifenazate (G12) and cyflumetofen (G12) were 31.29, 9.38 and 5.81, respectively. Realized heritability (h 2) analysis showed that, under a selection pressure of 50–90% mortality, the generations needed to increase 10‐fold LC50 values of bifenthrin, bifenazate and cyflumetofen were 3.64–8.05, 5.75–12.71, and 10.93–24.15, respectively. No obvious multi‐resistance among these three acaricides was observed. Synergist bioassay results showed that microsomal multifunctional oxidase (MFO) was involved in bifenthrin resistance of T. urticae, with a synergistic ratio of 22.38. However, MFO and GSTs were not the main factors conferring the resistance to bifenazate. MFO, glutathione S‐transferases(GSTs), together with esterase contributed to the development of the resistance to cyflumetofen. Additionally, the toxicity selection index test showed that bifenazate was safe to the natural enemy Neoseiulus barkeri (N. barkeri) with a toxicity selection index (TSI) >484.85, while bifenthrin was the least safe (TSI = 0.92). CONCLUSIONS These results demonstrated the T. urticae developed higher resistance risk to bifenthrin compared to bifenazate and cyflumetofen and no obvious multi‐resistance among these three acaricides, providing guidance for designing appropriate strategies for the effective application of bifenthrin, bifenazate and cyflumetofen in the field and delaying the development of insecticide resistance. © 2019 Society of Chemical Industry

Frequencies and mechanisms of pesticide resistance in Tetranychus urticae field populations in China

“…In the current study, the HD-BJ population had the lowest resistance to cyflumetofen and cyenopyrafen among the tested field populations; the HD-BJ population also had the lowest levels of activity of P450 and CarEs. This is consistent with previous reports that P450 and CarEs are jointly involved in resistance to cyflumetofen (Riga et al, 2015;Liu et al, 2020).…”

“…Our results showed that the LC 50 values of cyflumetofen, cyenopyrafen and B‐azolemiteacrylic, which function as respiratory chain complex inhibitors, ranged 1–52 mg/L among the seven field populations. Cyflumetofen is a semi‐esterase‐dependent precursor acaricide, which acts as a complex II inhibitor in the mitochondrial electron transport chain; previous research revealed that when esterase activity is inhibited, the toxicity of cyflumetofen is greatly reduced (Liu et al ., 2020). In the current study, the HD‐BJ population had the lowest resistance to cyflumetofen and cyenopyrafen among the tested field populations; the HD‐BJ population also had the lowest levels of activity of P450 and CarEs.…”

“…In the current study, the HD‐BJ population had the lowest resistance to cyflumetofen and cyenopyrafen among the tested field populations; the HD‐BJ population also had the lowest levels of activity of P450 and CarEs. This is consistent with previous reports that P450 and CarEs are jointly involved in resistance to cyflumetofen (Riga et al ., 2015; Liu et al ., 2020). Spinetoram, which was registered as an insecticide rather than an acaricide, had LC 50 values in the current study that ranged 5–80 mg/L, indicating that it is toxic to adult females of T. urticae .…”

“…Because of its short life cycle, high reproductive potential, arrhenotokous parthenogenesis and frequent exposure to pesticides, T. urticae has evolved resistance to most kinds of pesticides (van Leeuwen et al ., 2010). In China and other regions, T. urticae has developed resistance to organophosphates (OPs), carbamates, pyrethroids and even some recently developed compounds (Xu et al ., 2018b; Liu et al ., 2020; Namin et al ., 2020; Papapostolou et al ., 2021; Simma et al ., 2020; Solmaz et al ., 2020). Failures of chemical control resulting from resistance have frequently occurred in the field (van Leeuwen et al ., 2010; Funayama, 2015).…”

Pesticide Resistance and Related Mutation Frequencies of Tetranychus urticae in Hainan, China

“…Therefore, we suspect that other resistance mechanisms are involved in the resistance of the tested T. urticae populations to bifenthrin. In support of that possibility, mixed-function oxidase (MFO) was reported to be important for the bifenthrin resistance of T. urticae on cowpea in China [28]. The five T. urticae populations in the current study were moderately resistant to the organophosphate profenofos, even though the frequencies of G119S and A201S mutations, which are important for organophosphate resistance [29], ranged from 20% to 92% and from 2% to 80%, respectively.…”