【Aim】 To clarify the physiological mechanisms of the effects of elevated CO₂ on western flower thrips, Frankliniella occidentalis and its local related species F. intonsa. 【Methods】 The activities of the digestive enzymes (amylase, trypsin and lipase) in the adults of the two species of thrips reared on different host plants (kidney bean, garden chrysanthemum, pepper and cucumber) in elevated CO₂ (800 μL/L) and ambient CO₂ (400 μL/L) for three generations were determined and compared. 【Results】 The amylase activities in F. occidentalis and F. intonsa adults reared on the four host plants in elevated CO₂ were all lower than those in ambient CO₂. The amylase activities in F. occidentalis adults on kidney bean, cucumber, pepper and garden chrysanthemum decreased by 21.39%, 25.33%, 44.59% and 42.27%, respectively, while those in F. intonsa adults decreased by 48.79%, 49.47%, ,38.86% and 38.92%, respectively. In addition, the activities of lipase and trypsin increased significantly in F. occidentalis and F. intonsa adults reared on kidney bean, cucumber and pepper in elevated CO₂ than those in ambient CO₂ (P<0.05). The activities of lipase and trypsin in F. occidentalis adults on kidney bean foliages in elevated CO₂ were 2.00- and 2.49- fold as high as those in the control (in ambient CO₂)， respectively, while those in the populations reared on cucumber foliages were 2.36- and 2.27- fold as high as those in the control, respectively, while those in the populations reared on pepper foliages were 3.61- and 3.59-fold as high as those in the control,  respectively. For F. intonsa, the lipase activities in elevated CO₂ were only 1.76-， 2.18- and 2.69-fold as high as that in the control, respectively， while the trypsin activities in elevated CO₂ were only 1.72-, 2.19- and 2.42-fold as high as that in the control, respectively. 【Conclusion】 Both of CO₂ concentration and host plant species are the main factors altering the activities of these three digestive enzymes. Although F. occidentalis and F. intonsa may both alter the activities of their digestive enzymes to adapt the future elevated CO₂ environment, the invasive species F. occidentalis would be more adaptable to the changed environment than the local related species F. intonsa.

【Aim】 Lipophorin is a vital hemolymph lipoprotein, which delivers 90% of lipids to internal organs. This study aims to investigate the lipophorin composition during late larval， pupal and adult stages of the silkworm， Bombyx mori. 【Methods】 The compositional changes of hemolymph lipoprotein during various metamorphic stages were tested using potassium bromide density gradient ultracentrifugation, heparin sodium precipitation, and high performance liquid chromatography coupled with evaporative light scattering detector (HPLC-ELSD) methods. 【Results】 During the transition from the 5th instar larva to adult， the isolated lipophorin density was 1.130 g/mL in larval stage and 1.139 g/mL in spinning stage, but decreased in pupal stage (1.083 g/mL). The lipophorin subspecies estimated using a heparin sodium precipitation method showed that high density lipophorin was predominant (9.8 μg/μL) in the spinning stage. Low density lipophorin was increased from spinning stage and constantly present in pupal stage (4.2 μg/μL). Meantime the apolipophorin III content was low in all metamorphic stages and reached the highest in 2-day-old pupa (4 μg/μL). On the other hand, total lipid concentration gradually increased from the spinning stage to pupal stage (from 0.5 to 3.8 μg/μL). Neutral lipid composition estimated by HPLC-ELSD showed that monoacylglycerol was trace amount in all stages (<0.04 μg/μL). Diacylglycerol was noted in mid-5th instar larval to end of pupal stage (0.11-0.61 μg/μL), and triacylglycerol was found in pupal stage (0.18-1.02 μg/μL). 【Conclusion】 Overall results indicated that high density lipophorin mainly transported diacylglycerol during larval and spinning stages. After pupation, high density lipophorin was associated with more triacylglycerol than diacylglycerol, and with apolipophorin III to form the low density lipophorin. These observations suggest that lipophorin conversions are precisely timed processes.

【Aim】 The aim of this study is to reveal the function of peroxiredoxin 2 (ApPrx2) in the pea aphid, Acyrthosiphon pisum during bacterial infection. 【Methods】 The open reading frame of ApPrx2 was cloned and heterologously expressed in Escherichia coli. The antioxidative function of the purified recombinant ApPrx2 was characterized. The H₂O₂ concentration and ApPrx2 transcription level were detected in pea aphids after bacterial infections of Pseudomonas aeruginosa and Staphylococcus aureus. RNA interference was used to knockdown the expression of ApPrx2. H₂O₂ concentration, bacterial load and the survival rate of aphids were evaluated after the knockdown of ApPrx2. 【Results】 Sequence alignment showed that ApPrx2 is highly similar to 2-Cys Prxs from other insect species. In vitro assays demonstrated that the recombinant ApPrx2 protein degraded H₂O₂, and ApPrx2 expression rendered E. coli cells resistant to H₂O₂. Infections of the bacteria P. aeruginosa and S. aureus increased the H₂O₂ concentration and ApPrx2 expression in the pea aphids. The knockdown of ApPrx2 expression increased the H₂O₂ concentration, reduced the bacteria load and increased the mortality rate of aphids infected with S. aureus. 【Conclusion】 ApPrx2 functions as an antioxidative protein protecting pea aphids from stress induced by infection with bacteria, particularly S. aureus.

【Aim】 Estrogen-related receptors (ERRs) are a class of transcription factors that are dependent on ligand activation, which can respond to the stress of xenobiotic by regulating transcription levels of target genes and being involved in xenobiotic metabolism. In order to define the physiological functions of ERR in Laodelphax striatellus and its roles in insecticide metabolism, we cloned and characterized its ERR gene and analyzed its expression profiles after exposure to sulfoxaflor. 【Methods】 The ERR gene of L. striatellus was cloned using RT-PCR according to transcriptome data of L. striatellus and analyzed by bioinformatic tools, and its mRNA levels at different time and in different tissues of the 4th instar nymphs of L. striatellus after exposure to sulfoxaflor (0.76 ng/individual) were detected via real-time PCR. 【Results】 The ERR gene was cloned from L. striatellus， and named LsERR (GenBank accession no.: KY210878), its complete cDNA is 1 854 bp in length with a 1 260 bp of open reading frame， encoding a 47.70 kD protein with 419 amino acids. LsERR has the common conserved domains of NRs family, including the DNA-binding domain (DBD) (75-168 aa) and the ligand-binding domain (LBD) (194-416 aa). By using APSSP2 method, the predicted secondary structure of LsERR showed that the alpha helix accounts for 43.53%， the beta fold accounts for 5.49%, and the random coil accounts for 50.98%. There are six beta folds and three alpha helices in the DBD region while there are three beta folds and 11 alpha helices in the LBD region. Phylogenetic tree analysis indicated that LsERR is most closely related to Nilaparvata lugens ERR. In the 4th instar nymphs of L. striatellus exposed to sulfoxaflor, the expression level of LsERR increased at 12 h, reached the peak at 24 h, and decreased at 48 h. LsERR had weak expression in the head and high expression in the abdomen. 【Conclusion】 LsERR is a candidate gene involved in sulfoxaflor metabolism of L. striatellus. This study provides a molecular basis for the study of regulation of detoxification enzyme genes and the development of a novel molecular target of insecticides.

【Aim】 To explore the function of endophilin in the growth and reproduction of the brown planthopper, Nilaparvata lugens. 【Methods】 The endophilin genes of N. lugens were cloned and analyzed by bioinformatics. Then, recombinant prokaryotic expression vectors were constructed and transferred into Escherichia coli Rosetta to induce the expression of fusion proteins. After purification by Ni affinity chromatography, the fusion proteins were used to immunize the New Zealand rabbits to obtain polyclonal antibodies against endophilins. The obtained antibodies were used to detect the expression and localization of endophilins in N. lugens ovary. 【Results】 Two endophilin genes， endophilin A (Endo A) and endophilin B (Endo B), were cloned from N. lugens, with the GenBank accession numbers of KY126096 and KY126095, respectively. Endo A and Endo B encode 387 and 352 amino acids, respectively. Both encoded proteins contain the typical BAR domain and SH3 domain, but show different structure. The titer of the obtained antibodies was estimated as high as 1∶1 000 000 dilution ratio through ELISA, and the antibodies had good specificity as shown by Western blot. Using immunofluorescence, the antibodies were used to detect the expression of Endo A and Endo B in N. lugens ovary. The results indicated that Endo A and Endo B were universally expressed in N. lugens ovary. In ovary, Endo A and Endo B were widely distributed in the extracellular space, cytomembrane and cytoplasm of follicle cells of N. lugens ovary, and this distribution pattern was similar to that of lipids. Meanwhile, Endo A and Endo B were colocalized with yeast-like symbionts invading into N. lugens ovary. 【Conclusion】 The nucleotide sequences and the biological characteristics of Endo A and Endo B were clarified. With the obtained polyclonal antibodies of Endo A and Endo B, the expression of Endo A and Endo B in N. lugens ovary was profiled, and the results suggest that Endo A and Endo B might be associated with the development and maturity of N. lugens ovary as well as the invasion of the yeast-like endosymbionts to N. lugens ovary. These results lay the foundation for further studies on the biological function of Endo A and Endo B in N. lugens.

【Aim】 To understand the mechanisms underlying cold tolerance and to discover novel cold-tolerant genes in the desert beetle Microdera punctipennis. 【Methods】 The chitinase gene in M. punctipennis was cloned by screening cold stress transcriptome data and analyzed by bioinformatics. Its expression profiles in response to low temperature (4℃) stress and in different adult tissues were detected by real-time fluorescence quantitative PCR and immunohistochemistry. 【Results】 A chitinase gene named Mpcht19 (GenBank accession no.: KY126382) was cloned from M. punctipennis adult. Bioinformatics analysis showed that the protein MpCHT19 encoded by Mpcht19 belongs to the type IV insect chitinase family. It is hydrophilic, and the predicted molecular weight is 27.18 kD with no signal peptide. Phylogenetic analysis showed that MpCHT19 is similar to TcCHT19 of Tribolium castaneum with the amino acid sequence identity of 34.05%. The results of real-time fluorescent quantitative PCR showed that the expression of Mpcht19 was high in the fat body and hindgut with tissue specificity. In addition, its expression was also induced by low temperature of 4℃. Immunohistochemical analysis showed that MpCHT19 protein was expressed in the fat body and hindgut at 4℃. 【Conclusion】 The expression of Mpcht19 shows the tissue specificity, and is low temperature inducible. The results may help to further investigate the relationship between chitinase function and cold tolerance of M. punctipennis.

【Aim】 Cry resistance developed in target pests has been caused by the sustainable planting of Bt crops. Previous work indicated that the down-regulation of white gene is tightly linked to Cry1Ac resistance in Plutella xylostella, and Pxwhite and ATP-binding cassette transporter ABCG1 belong to ABCG subfamily, so we predict that the similar change of ABCG1 gene expression may be associated with the Cry1Ac resistance in Helicoverpa armigera. 【Methods】 The open reading frame (ORF) of HaABCG1 was cloned from H. armigera, the subcellular localization of HaABCG1 protein in TnH5 cells was detected by constructing expression vector of HaABCG1, the ABCG1 protein as the receptor of Cry1Ac toxin with cytotoxicity of Bt toxin was confirmed by cytotoxicity tests, and whether the down-regulation of HaABCG1 could decrease the susceptibility of H. armigera to Cry1Ac toxin was confirmed by RNA interference (RNAi) and bioassay. 【Results】 The open reading frame of HaABCG1 is 1 896 bp, encoding 631 amino acid residues with the predicted molecular weight of 69.63 kD. HaABCG1GFP is mainly localized on the nuclear membrane and endoplasmic reticulum of TnH5 cells. RNAi-mediated suppression of HaABCG1 expression did not decrease the susceptibility of H. armigera to Cry1Ac toxin, and the body weight change had no significant difference between the experimental group and the control group reared on artificial diet containing 0.05 μg/mL Cry1Ac for 3 d after RNAi. HaABCG1 protein did not mediate the cytotoxicity of Cry1Ac to TnH5 cells, and it was neither the receptor of Cry1Ac, nor the receptor of Cry1Ca, Cry2Aa or Cry1Fa. 【Conclusion】 The results suggest that the down-regulation of HaABCG1 is not associated with Cry1Ac resistance in H. armigera, and HaABCG1 is not the receptor of Cry1Ac. This is the first report that ABCG1 gene is not involved in the Cry1Ac resistance of H. armigera.

【Aim】 MicroRNAs (miRNAs) are a class of non-coding RNAs that are widely present in eukaryotes and involved in the regulation of many life processes. The formation of new cuticle and the degradation of old cuticle are necessary for insect molting. This study aims to identify the miRNAs targeting key genes involved in cuticle metabolism in the locust Locusta migratoria, which may provide an experimental foundation for investigating the molecular regulation mechanism of cuticle metabolism and also be helpful to developing new molecular targets for pest control. 【Methods】 Potential miRNAs that bind key genes involved in cuticle metabolism of L. migratoria were identified by using bioinformatics approaches. Reverse transcription quantitative PCR (RT-qPCR) was used to detect the expression patterns of cuticular genes and the miRNAs targeting them in the day-1, day-3 and day-5 2nd and 3rd instar nymphs. The RNA immunoprecipitation (RIP) and dual luciferase reporter assays were performed to validate the potential binding relationship of miRNAs and their target genes in vivo or in vitro. 【Results】 The bioinformatics prediction results showed that four cuticle metabolism related genes from L. migratoria, i.e., fatty acid synthase (FAS) gene, UDP-N-acetylglucosamine pyrophosphorylase (UAP) gene, asparagine-linked glycosylation protein 5 (ALG5) gene and Sinuous gene, contain potential binding sites for miRNA-276b, miRNA-2796, miRNA-275 and miRNA-184, respectively. RT-qPCR analysis showed that FAS, UAP, ALG5 and Sinuous exhibited similar expression patterns in the cuticle of different day-old 2nd and 3rd instar nymphs. The expression pattern of FAS presented a positive correlation with that of miRNA-276b targeting it, whereas the expression patterns of the other three genes were negatively correlated with those of the miRNAs targeting them respectively. RIP assays suggested that FAS, UAP, ALG5 and Sinuous, as well as the miRNAs targeting them, were significantly enriched in vivo. Dual luciferase reporter assay showed that miRNA-276b, miRNA-2796, miRNA-275 and miRNA-184 had a significant inhibitory effect on the expressions of FAS, UAP, ALG5 and Sinuous genes, respectively, in vitro. 【Conclusion】 We identified the miRNAs targeting four cuticle genes from L. migratoria, which provides the basis for further study of the regulation mechanism of miRNAs on molt development and the discovery of new targets for pest control.

【Aim】 The green lacewing, Chrysopa pallens (Rambur), is an important natural enemy insect and enters diapause as prepupa in winter. This study aims to understand the effects of photoperiod and temperature on diapause termination and post-diapause development and reproduction of C. pallens. 【Methods】 The diapause termination and post-diapause biology including pupal duration, pupal survival rate, adult fresh weight, adult longevity, preoviposition period and number of eggs laid per female of C. pallens were observed after the diapaused prepupae were treated under different combinations of temperatures (22℃ and 25℃) and photoperiods (15L∶9D and 9L∶15D). The effects of chilling at 5℃ on diapause termination, and diapause duration on the post-diapause development and reproduction of C. pallens were also investigated. 【Results】 The prepupal duration under the photoperiods of 15L∶9D and 9L∶15D at 25℃ (50.09 and 49.47 d, respectively) was significantly shorter than those at 22℃ (80.80 and 82.20 d, respectively). The chilling treatment at 5℃ prolonged the prepupal duration extremely significantly (P<0.01), and deceased the individual difference of prepupal duration. At 22℃, compared with the non-diapause prepupa, for the diapaused prepupa the survival rate was significantly decreased, the pupal duration and preoviposition period were significantly prolonged, the female adult longevity was significantly shortened, and the adult fresh weight and the number of eggs laid per female were significantly decreased. The diapause duration of C. pallens was 50-170 d at 22℃ under a photoperiod of 15L∶9D, and the post diapause development was affected, with the pupal duration gradually prolonged, the adult fresh weight decreasing, and the male adult longevity initially increasing and then decreasing, but with no significant differences in the pupal survival rate, female adult longevity, preoviposition period and number of eggs laid per female. 【Conclusion】 Under the experimental conditions, the tested photoperiods have no significant effects on the diapause termination and post-diapause development and reproduction in C. pallens, while temperature is the key factor to regulate diapause development and reproduction. Higher temperature promotes the termination of diapause, and chilling can synchronize population diapause development. There is reproduction cost in diapaused C. pallens, and diapause duration affects some of its post-diapause biological characteristics.

【Aim】 This study aims to understand the oviposition selection of Drosophila suzukii on cherries (Cerasus pseudocerasus) and the relationship of oviposition selection to physiological characteristics of cherry fruits. 【Methods】 The oviposition selection of D. suzukii on four cherry varieties (Huangmi, Hongdeng, Van and Summit) was tested by inducing oviposition of D. suzukii using intact cherry and sliced cherry, respectively. The physiological characteristics of cherry fruits, including the fruit rigidity and the contents of proteins, amino acids, glycogen and pectin, were tested. The correlation between the oviposition selection of D. suzukii and the physiological characteristics of cherry fruits were analyzed. 【Results】 The cherry varieties with higher glycogen content and lower pectin content (Huangmi and Hongdeng) were the most readily chosen hosts for oviposition of D. suzukii. The oviposition selection of D. suzukii on the intact cherry was related to fruit rigidity. The fecundity was higher in the varieties with lower fruit rigidity (Van and Summit). However, there was no significant correlation between the oviposition selection of D. suzukii and the contents of proteins and amino acids in cherry fruits. 【Conclusion】 The selectivity of oviposition of D. suzukii on the four cherry varieties is significantly different, which is related to the nutrient contents and rigidity of cherry fruits.

 【Aim】 The objective of this research is to analyze and predict the potential geographical distributions of two important mirid predators Tytthus chinensis and Cyrtorhinus lividipennis, of rice planthoppers, and to study the effects of climatic factors on their potential geographical distribution. 【Methods】 Maximum entropy niche-based modeling (MaxEnt) was used to predict species geographical distributions based on maximum entropy. The distribution records of the two mirid species and a set of environmental predictor variables were used to model the suitable geographical distributions of the two species. 【Results】 The results showed that the principal geographical distribution areas of T. chinensis were Southeast China, East Asia, Southeast Asia and parts of the Indonesia or within the geographical biomes of the Oriental and Australia. The suitable distribution areas of C. lividipennis were relatively broader in comparison with those of T. chinensis. In addition to the distribution area of T. chinensis, C. lividipennis could possibly survive in Shandong, Hebei, Shaanxi and Yunnan provinces in China, and the Amazon region as well. The suitability of T. chinensis and C. lividipennis was found to be affected significantly by the precipitation in the warmest season and the mean diurnal range. Especially, the precipitation in the warmest season exceeding 500 mm and the mean diurnal range monthly below 10℃ are the more favorable conditions for the distribution of T. chinensis and C. lividipennis. 【Conclusion】 Our results revealed that the suitable distribution of these two predators is primarily affected by the precipitation in the warmest season and the mean diurnal temperature range monthly. This study provides some important evidence for successful biological control of the two mirids in these potential distribution regions.

Autophagy is a ubiquitous process of intracellular self-degradation, which is well conserved from yeasts to mammals and strictly regulated by upstream signaling pathways such as energy and nutrient. Studies in mammals have shown that autophagy has a close relationship with lipid metabolism. Autophagy could be induced by high level of lipid in dietary, while knockout of some autophagy related genes (Atg) can block lipid degradation in liver and cause accumulation of lipid droplets. Studies in insects also imply that autophagy is important for lipid degradation. Up to now, there are still many questions remaining unanswered on the autophagy-mediated lipid metabolism. Besides a few identified ATG proteins, whether some other ATG proteins are also involved in lipid metabolism has not been reported. The molecular mechanism of lipid metabolism regulated by identified ATG proteins is unclear. What enzymes in the lysosome participate in autophagy-mediated lipid metabolism has not been confirmed. In addition, ATG proteins differently participate in lipid droplet formation and lipid degradation in fungi and higher animals, but the mechanism is unknown. The evolutionary status of insects is between fungi and higher animals, the studies of autophagy-mediated lipid metabolism in insects will be helpful for uncovering the mechanisms underlying obesity and hyperlipidemia in higher animals, and also have great significance in the researches with the metabolism and development in the fat body of insects as the regulating targets. So in this article we summarized the progress of autophagy-mediated lipid metabolism mainly in mammals, and introduced the research methods and detection techniques of lipid metabolism to enlighten the related studies in insects and other organisms.

【Aim】 The scientific name of black glue whitefly is Aleuroplatus pectiniferus Quaintance & Baker. In some previous reports, Aleurotrachelus camelliae (Kuwana) was misidentified as black glue whitefly. In this study, we distinguished A. pectiniferus and A. camelliae by comparing their morphological differentiation. 【Methods】 We redescribed these two species of whiteflies collected by mounting the slide specimens and observation under scanning electron microscope (SEM). 【Results】 The morphological characteristics of puparium were redescribed， and the data of host plants and distribution and the live images and slide and SEM photographs of puparia of these two whitefly species were provided. A. pectiniferus resembles A. camelliae in the presence of the white wax secretions at the end of thoracic and caudal tracheal folds, but differs from the latter in the smaller size of puparium, the presence of the comb structure composing of 3-4 teeth at the end of thoracic and caudal tracheal folds， and the presence of the submedian depressions on each abdominal segment. 【Conclusion】 We unified and proposed the Chinese common name for A. pectiniferus and A. camelliae, respectively.