In this study, we cloned a full-length cDNA of heat shock protein (HSP) gene of Apolygus lucorum (Meyer-Dür) [AlHSP90, KC109781] and investigated its expression in response to temperature and pesticide stresses. The open reading frame (ORF) of AlHSP90 is 2,169 bp in length, encoding a 722 amino acid polypeptide with a predicted molecular weight of 82.99 kDa. Transcriptional and translational expression profiles of AlHSP90 under extreme temperature or pesticide stresses were examined by fluorescent realtime quantitative PCR and Western blot. Results showed that the expression profiles of AlHSP90 protein were in high agreement with those of AlHSP90 RNA and indicated that AlHSP90 was not only an important gene for A. lucorum adults in response to extremely high temperature, but also involved in the resistance or tolerance to cyhalothrin, imidacloprid, chlorpyrifos, and emamectin benzoate, especially for female adults to emamectin benzoate and for male adults to cyhalothrin. Transcriptional results of AlHSP90 also confirmed that AlHSP90 was an important gene involved in the resistance or tolerance to both temperature and pesticide stresses. In addition, our study also revealed that ∼24°C may be the suitable temperature range for A. lucorum survival, which is also confirmed by the results of the expression of AlHSP90, the nymph mortality, and the intrinsic rate of increase (r m ) when A. lucorum is reared at six different temperatures. Therefore, these studies are significant in elucidating the AlHSP90 in response to temperature and pesticide stresses and would provide guidance for A. lucorum management with different pesticides or temperatures in fields.

Host plant type and suitability could affect the expression pattern of SeVg and SeVgR, which influenced S. exigua fecundity. Vg and VgR have the potential to be used as molecular markers of S. exigua fecundity and for forecasting outbreaks of S. exigua on different hosts. © 2017 Society of Chemical Industry.

Heat shock cognate protein 70 (Hsc70) is a very important stress-resistance protein of insects against environmental stresses. We employed fluorescent real-time quantitative polymerase chain reaction and Western-blot techniques to analyze the transcriptional and translational expression profiles of AlHSC70 under extreme temperature (4°C and 40°C) or 4 pesticide stresses in Apolygus lucorum. The results showed that the expression of AlHSC70 were significantly induced by cyhalothrin or extremely high temperature (40°C) in both transcriptional and translational levels (P < 0.05), while the transcriptional and translational level of AlHSC70 decreased significantly in treatments of chlorpyrifos or extreme cold temperature (4°C) (P < 0.05). Moreover, after Apolygus lucorum treated by imidacloprid or emamectin benzoate, the expression of AlHSC70 was only up-regulated significantly at the transcriptional level (P < 0.05), although obviously up-regulated at the translational level of AlHSC70. Therefore, this study confirmed that the Alhsc70 gene played important roles in response to both temperature and pesticide stresses, especially for cyhalothrin or extremely high temperature (40°C). In addition, the significant polynomial regression correlations between temperature and the Alhsc70 expression level were shown in all the nymph and adult stages (P < 0.01), indicating temperature was an important factor to affect the relative expression of Alhsc70.