Population Numbers and Physiological Response of an Invasive and Native Thrip Species Following Repeated Exposure to Imidacloprid

Abstract

Frankliniella occidentalis and F. intonsa are devastating pest insects that target Rosa rugosa, Chrysanthemum morifolium, and Phaseolus vulgaris, which are important economical horticultural plants in China. Meanwhile, R. rugosa and C. morifolium are important cash plants in Kunming, South China. We focus on the population performance of these two thrips species on these three host plants with or without repeated exposure to imidacloprid in Kunming. In the field, the population numbers of F. occidentalis developed faster and were larger on these three sampled host plants, especially under imidacloprid exposure, compared with F. intonsa. The activity of the detoxifying enzymes (CarE, AchE, and MFO) and the antioxidant enzymes (CAT and POD) in both thrips species were significantly enhanced under imidacloprid exposure, whereas the activities of SOD in both thrips were significantly decreased on these three host plants, compared with the control. Overall, enzyme activity of F. occidentalis showed a greater increase than that observed in F. intonsa in most cases, which could be exploited in further studies on thrips resistance management.

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

“…Zhang et al . reported that imidacloprid treatment significantly up‐regulated the activities of detoxifying enzymes (CarE, AChE and MFO) in both F. occidentalis and F. intonsa 21 . The findings of the present study show that spinetoram exerts similar effects in both species.…”

“…F. occidentalis adapted better to adverse ecological conditions than F. intonsa 3 . Both thrips species adapt to adverse environmental conditions such as elevated CO 2 or insecticides by altering the activities of physiological enzymes 21,49 . The findings of the current study showed that elevated CO 2 decreased SOD activity in both thrip species, but increased POD and CAT activity.…”

“…A previous study reported that spinosad treatment increases the activities of SOD, POD and CAT in larvae of Malacosoma neustria testacea 55 . A related study reported that imidacloprid treatment up‐regulated activity of CAT and POD in F. occidentalis and F. intonsa on three host plants, but decreased the activity of SOD in the two species 21 . This conflicting finding can be attributed to the different mechanisms of the different insecticides used and differences in sampling of insects.…”

“…Protective and detoxifying enzymes are used as potential tools for evaluating the development of resistance in agricultural pests 20 . Studies report that insects protect themselves against insecticides such as imidacloprid by up‐regulating the activities of protective (POD and CAT) and detoxifying enzymes (CarE, GST and AChE) 21 . Similar studies have reported that treatment with chlorpyrifos, bifenthrin, lufenuron, lambda cyhalothrin, and emamectin benzoate increases AChE activity in the larvae of Helicoverpa armigera 22 .…”

Effect of short-term exposure to high temperatures on reproductive behaviors and physiological enzyme activities in Zeugodacus tau

“…The activities of SOD, POD, CAT, AchE, GST, and CarE were determined according to the kit instructions (Beijing Solarbio Science & Technology Co., Ltd., Beijing, China). The enzyme activity was calculated based on the sample mass using UV-Vis spectrophotometry (Zhang et al, 2020). Each treatment comprised 3 replicates.…”