Historical changes in the lethal effects of insecticides against the diamondback moth, Plutella xylostella (L.)

Abstract

BACKGROUND: The diamondback moth, Plutella xylostella (L.), is one of the most destructive pests owing to the rapid development of resistance to various groups of insecticides. Although the rotation strategy has become common, resistance management continues to be a critical issue. RESULTS: In Japan, historical changes in the susceptibility of P. xylostella to insecticides were estimated using 82 references. The meta-analysis using generalized linear mixed models suggested that each mode of action (MoA) had different patterns of changes to the susceptibility, which might be due to the prevalence of the rotation strategy since the 2010s and the fitness cost of the resistance gene. For example, spinosyns and bacterial insecticide Bacillus thuringiensis (Bt), for which resistance has a high fitness cost, maintained high lethal effects on P. xylostella throughout several decades. However, pyrethroids and benzoylureas, for which resistance has no or little fitness cost, remained at low levels of susceptibility regardless of the rotation strategy.CONCLUSION: Our findings suggest optimal combinations of MoA for a sustainable rotation strategy based on their stability and recovery of effectiveness. Susceptibility monitoring using our method and further study of fitness costs will improve the rotation strategy concerning P. xylostella in the future.

Adult Mosquito and Butterfly Exposure to Permethrin and Relative Risk Following ULV Sprays from a Truck-Mounted Sprayer

“…It is possible that nontarget Lepidopterans could also develop resistance to permethrin. Resistance development in pest Lepidopteran species has been reported (Jia et al 2009 ; Grigg-McGuffin et al 2015 ; Uesugi 2020 ; Sun et al 2022 ) and has been reported in a nontarget aquatic invertebrate (Major et al 2022 ). The common aspect of this resistance development is that it occurs in organisms either targeted by the applications or are unintentionally routinely exposed to the insecticide.…”

Fitness costs of resistance to insecticides in insects

“…Since 2010, Japanese farmers have used the rotation of pesticides with varied modes of action for resistance management. Nonetheless, this technique produces variations in their mortalities ( Uesugi, 2021 ) (IRAC 2019). Fitness costs related to using insecticides could be a possible reason for this disparity, resulting in varying susceptibility against the different modes of action affecting resistance stability ( Jouzani et al, 2017 ).…”

“…Fitness costs related to using insecticides could be a possible reason for this disparity, resulting in varying susceptibility against the different modes of action affecting resistance stability ( Jouzani et al, 2017 ). Bt, spinosyns, pyridalyl, and aver-mectins/milbemycins may become key components of the rotation approach because their high fitness costs lead to steady and high susceptibility ( Jouzani et al, 2017 ; Yin et al, 2019 ; Uesugi, 2021 ; Kumar et al, 2022 ).…”

Discovery of a Novel Class of Acylthiourea-Containing Isoxazoline Insecticides against Plutella xylostella

“…The challenge of managing this moth is exacerbated by its strong reproductive potential, rapid generation turnover, protracted growing period, and extensive migration range [3]. The rapid evolution of drug resistance owing to the irrational use of insecticides has made its control a major concern for many countries, yet there is a dearth of effective agrochemicals on the market to combat it [4,5]. It has been found that the moth is highly resistant to organophosphorus, carbamates, pyrethroids, novel chemical insecticides, and toxins from Bacillus thuringiensis at the present time [1,6,7].…”