Effects of elevated CO₂ on activities of protective and detoxifying enzymes in Frankliniella occidentalis and F. intonsa under spinetoram stress

Abstract

BACKGROUND Elevated CO2 can directly affect the toxicity of insecticides to insects and the physiological response of insects to insecticides. Frankliniella occidentalis and F. intonsa are highly destructive pests that target horticultural crops. Spinetoram is an effective pesticide against thrips. This study sought to explore the effect of elevated CO2 on efficacy of spinetoram against F. occidentalis and F. intonsa and effect of the spinetoram on activities of protective and detoxifying enzymes under elevated CO2. Notably, these enzymes can be exploited in further studies to develop interventions for thrips resistance management. RESULTS Toxicity bioassay showed that the LC50 values of F. occidentalis and F. intonsa exposed to spinetoram at elevated CO2 (800 μL L−1 concentration) for 48 h was 0.08 and 0.006 mg L−1, respectively, which is 0.62 and 0.75 times of the values at ambient CO2 (400 μL L−1 concentration). The findings showed that elevated CO2 decreased activities of the superoxide dismutase and acetylcholinesterase in thrips, while increasing the activities of carboxylesterase and glutathione S‐transferase. However, spinetoram increased activities of protective and detoxifying enzymes in both thrips under the two CO2 levels. Elevated CO2 and spinetoram affect the physiological enzyme activity in thrips synergistically, and the activities of analyzed enzymes were generally higher in F. occidentalis than in F. intonsa. CONCLUSION Elevated CO2 amplifies the efficacy of spinetoram on thrips, F. intonsa is more susceptibility to spinetoram than F. occidentalis and the latter showed better adaptation to adverse conditions than the former. © 2021 Society of Chemical Industry.

Insecticide Susceptibility and Detoxification Enzyme Activity of Frankliniella occidentalis under Three Habitat Conditions

“…In the current study, the decreased susceptibility of F. occidentalis to spinetoram was linked to changes in CarE activity, suggesting that CarE plays a role in the detoxification metabolism of spinetoram. Previous studies showed that spinetoram treatment can increase the activities of CarE in F. occidentalis [37]. However, the precise mechanism by which of spinetoram stress induces increased activity of CarE should be explored further.…”

“…Carboxylesterase (CarE), glutathione S-transferase (GST), acetylcholinesterase (AChE), and the cytochrome P450 enzyme system (CYP450) are important metabolic detoxifying enzymes found in insects. Detoxification enzymes in insects are induced by various exogenous or endogenous compounds, meaning that insects can quickly adapt to environmental stresses, such as insecticides [33], extreme temperatures [36] and carbon dioxide [37], etc. Research has shown that insecticides have different effects on insect defense enzyme systems, and that the changes in the activity of the enzymes are related to the toxic death of insects or indeed the development of insect resistance.…”

Identification and characterization of Prx5 and Prx6 in Chilo suppressalis in response to environmental stress

“…It is known that pesticide intoxication produces oxidative stress in insects, thus, the organism reacts and metabolizes the pesticide active ingredient, inducing lipid peroxidation (Cui et al, 2017; Hu et al, 2019; Li et al, 2021; Sule et al, 2022; Valeria et al, 2020). Chlorantrailiprole and spinetoram are two of the most used insecticides for controlling C. suppressalis , and high concentrations of ROS can be caused by exposure to the two pesticides (Fan et al, 2022). Our results were consistent with these observations that both two pesticides stimulated the expression of CsPrx5 and CsPrx6 in C. suppressalis , indicating that these two Prxs play a significant role in the antioxidant process.…”

Comparison and Functional Analysis of Odorant-Binding Proteins and Chemosensory Proteins in Two Closely Related Thrips Species, Frankliniella occidentalis and Frankliniella intonsa (Thysanoptera: Thripidae) Based on Antennal Transcriptome Analysis

“…Due to similar niches, competitive interaction between F. occidentalis and F. intonsa has been frequently reported. It has been reported that the relative abundances between F. occidentalis and F. intonsa varies depending on plant hosts and abiotic conditions [44][45][46][47][48][49]. Our previous study found that species-specific aggregation pheromones regulated by the ratio of pheromone compounds might also contribute to the coexistence of the two thrips species [50].…”