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Insecticides can have consequences for beneficial arthropods. Insect parasitoids can contact insecticides through direct exposure spray droplets or residues on crop foliage. Here, we focus on better understand the response of Meteorus pulchricornis (Wesmael), a parasitoid wasp of lepidopteran pests, and its detoxification mechanisms on stress caused by phoxim and cypermethrin. Hence, we determined the dose-mortality curves and estimating the sublethal concentrations (LC30 and LC50). Then, we applied the sublethal concentrations against adult parasitoids to assess its survival, parasitism efficacy, and also developmental and morphometric parameters of their offspring. Simultaneously, we check the activities of glutathione S-transferase (GST), acetylcholinesterase (AChE), and peroxidase (POD) after sublethal exposure of both insecticides, which has measured until 48 h after treatment. Overall, phoxim and cypermethrin exhibited acute lethal activity toward the parasitoid with LC50 values 4.608 and 8.570 mg/liter, respectively. Also, we detect that LC30 was able to trigger the enzymatic activity of GST, AChE, and POD, suggesting a potential detoxification mechanism. However, even when subjected to sublethal exposure, our results indicate strong negatives effects, in particular for phoxim, which has affected the parasitism efficacy and also the developmental and morphometric parameters of M. pulchricornis offspring. Therefore, it can be concluded that both phoxim and cypermethrin have negative impacts on M. pulchricornis and we suggest cautioning their use and the need for semifield and field assessments to confirm such an impact., (© The Author(s) 2021. Published by Oxford University Press on behalf of Entomological Society of America.)

Six candidate sHSP genes were identified from the Glyphodes pyloalis transcriptome. All sHSP genes included full-length open reading frames and shared high similarity with the sequences of other lepidopteran species. These sHSP genes encoded 175-191 amino acid residues, and the predicted proteins had a molecular weight from 19.5 to 21.8 kDa. All GpsHSPs were expressed at lower levels at larval stages. All GpsHSPs were expressed at higher levels at diapaused, prepupal, or pupal stages, suggesting that sHSPs may be involved in metamorphosis in G. pyloalis. In addition to the developmental stage, extreme temperatures can induce variations in the expression of sHSPs genes. All GpsHSPs were significantly upregulated in larvae following exposure to heat shock, except GpHSP21.4 which downregulated at 4 h following exposure to the cold shock treatment. Furthermore, Starvation influenced the expression patterns of GpsHSPs as a function of the duration of food deprivation. Four GpsHSPs increased their expression with time of starvation until reaching to the peak level at 6 d of starvation. Finally, parasitism by the endoparasitoid Aulacocentrum confusum He et van Achterberg (Hymenoptera: Braconidae)-induced fluctuations in the expression of all GpsHSPs, and the expression varied with time after parasitization. Our results from this study strongly suggest functional differentiation within the sHSPs subfamily in G. pyloalis. The present study would provide further insight into the roles of sHSPs in G. pyloalis and novel avenues for promoting integrated management of this pest., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America.)