【Aim】To understand the effects of habitat changes on the bacterial communities in the larval gut of chironomids by studying the diversity and potential function of bacterial communities in the gut of Propsilocerus akamusi, a pollution-resistant chironomid identified in the freshwater area of the heavy metal polluted Bohai Bay of Tianjin City. 【Methods】The 4th instar larvae of P. akamusi identified in the freshwater area of the heavy metal polluted Bohai Bay of Tianjin City were raised with distilled water in laboratory for 7 d as the laboratory-cultured group, and the bacterial genomic DNA in the 4th instar larval gut of P. akamusi from the laboratory-cultured group and the wild-captured group was extracted. The high-throughput sequencing of the V3-V4 region of 16S rRNA gene was carried out, and the sequencing results were subjected to data quality control, sequence alignment and filtering, the changes in the species composition of gut bacterial communities were analyzed and the potential functions of gut bacteria were predicted. 【Results】Based on the 16S rRNA sequencing results of the gut bacteria in the 4th instar larvae of P. akamusi, 11 phyla, 13 classes, 33 orders, 54 families, 71 genera, 90 species and 105 operational taxonomic units (OTUs) were annotated. The diversity and abundance of bacterial communities in the 4th instar larval gut of P. akamusi in the laboratory-cultured group were lower than those in the wild-captured group. The dominant bacterial phyla in the 4th instar larval gut of the two groups were similar, including Firmicutes, Proteobacteria, Bacteroidota and Desulfobacterota. The abundance of Proteobacteria in the 4th instar larval gut of the wild-captured group was significantly higher than that in the laboratory-cultured group. The average abundance of Aeromonas, Shewanella, Serratia, Pseudomonas and Yersinia in the 4th instar larval gut in the laboratory-cultured group was significantly lower than that in the wild-captured group. The results of linear discriminant analysis revealed that there were bacterial species with significantly different abundance in the 4th instar larval gut of P. akamusi between the wild-captured group and the laboratory-cultured group. The KEGG analysis results showed that the relative abundance of metabolism-related genes in the bacterial genome of the 4th instar larval gut of P. akamusi was extremely high. The relative abundance of genes related to environmental information processing and cellular processes in the gut bacterial genome of the 4th instar larva of P. akamusi in the laboratory-cultured group significantly decreased as compared to that in the wild-captured group.【Conclusion】The results of this study indicate that there are significant differences in the diversity of the gut bacterial communities and gene functions between P. akamusi larvae living in adverse field environments and those reared in laboratory pure water environments. This helps to study the individual resistance mechanisms of chironomids from an environmental perspective, provides a new idea for further exploring the mechanism of the symbiotic microorganisms in the gut of chironomid larvae to cope with environmental stress, and also lays a foundation for the study of the tolerance mechanism of insects in adverse environmental conditions and the regulatory mechanism of homeostasis of their gut microbial communities.

Insect symbionts are microorganisms that establish enduring and sustained associations with insect hosts. These microorganisms inhabit the body surface, gut, hemocoel, or intracellular cells of insects, participating in the regulation of various physiological functions of their host insects. Research on insect-symbiont interactions involves multidisciplinary collaboration. In-depth exploration of the functions of insect symbionts and their interactions with hosts not only advances our understanding of fundamental mechanisms in the life sciences but also introduces innovative perspectives and methods for pest management, vector-borne disease control, and optimal utilization of beneficial insects. In recent years, Chinese researchers have made noteworthy progress in the insect microbiome and got significant achievements in many research directions. In this article, we provided an overview of the most recent research progress in insect symbionts, introduced the main contents of this special issue, and proposed three noteworthy research directions: (1) the functions of insect intracellular symbionts; (2) the mechanisms by which insects regulate the abundance and transmission of symbionts; and (3) genetic modification and application of insect symbionts.

 The red imported fire ant, Solenopsis invicta, is a primary invasive pest in China. Currently, scientific researches, control strategies and policy regulations regarding S. invicta mainly focus on the filed of agriculture in China. Although S. invicta is also widely distributed in forests, grasslands, wetlands and urban green spaces and has caused huge damage, the occurrence characteristics and control strategies of S. invicta in these areas are largely overlooked. The occurence of S. invicta is closely associated with human disturbances such as felling, burning and soil turning, and natural factors such as biodiversity, forest canopy density and soil bareness. Due to the low levels of biological diversity and forest canopy density and high levels of human disturbances, there is a high risk of S. invicta invasion in plantation forests and adjacent areas. In natural forests, S. invicta is usually distributed in forest edges and windows, as well as burned areas where the sunlight can directly irradiate. Moreover, nurseries and urban green spaces have a high risk of S. invicta invasion because of large areas of bare soil and high levels of human activities. In areas with high levels of human activities, including plantation forests, nurseries and urban green spaces, S. invicta mainly threatens human health and infrastructure, and directly or indirectly damages trees. In addition, the invasion of S. invicta significantly decreases the abundance and diversity of arthropods in habitats and poses significant threats to wildlife in natural reserves and wetlands. Although it has been reported that S. invicta contributes to promoting seed migration and enhancing soil nutrient circulation under certain conditions, its harmful impacts far exceed its potential beneficial effects. Quarantine, monitoring and control are three important aspects to prevent S. invicta invasion in forestry. Wood, seedlings with soil, and turf are the main objects that may carry S. invicta and need to be quarantined, and fumigation can effectively eliminate S. invicta. Baiting and trapping are the main methods to monitor S. invicta. Recently, some new technologies, including remote sensing and radar technology, also have been developed to monitor S. invicta in grasslands and urban green spaces. Although chemical control is the most predominant control strategy for S. invicta, the use of highly toxic, broad spectrum and hardly degradable insecticides may negatively affect non-target organisms in natural reserves and wetlands. Therefore, it is essential to develop environmentally friendly agents and methods to control S. invicta.

The collective set of odors received by insects is called as insect odorscape. Insects rely on the reception and discrimination of the odorscape to complete life activities, such as the object localization, feeding, mating and oviposition. The behavior of insects can be manipulated by odorscape management for pest control strategy. In this article, we reviewed the research progress in the composition and diffusion of insect odorscape, influences of odorscape on insect behavior, factors affecting odorscape, odorscape reception and discrimination of insects, and the application of odorscape management in pest control. Finally, we analyzed and prospected the development direction and research focus of insect odorscape management in the future. For insects, the odor released by target is dispersed into plumes by air flow and mixed with the background odor carried in the air, which together form the odorscape. Insects search and locate the target along the target odor. The behavior of insects can be affected by the shape, composition and concentration of target odors. The background odor plays a complementary or warning role during the target localization of insects. Different background odors can synergize or interfere with the target localization of insects. The insect odorscape is mainly affected by the temperature, humidity, light, heavy metal elements and plant diseases and insect pests in the environment. Studies showed that the olfactory receptors of insects capture odorscape and transmit those odor signals to olfactory nerve centers such as antennal sensilla lobe along the olfactory nerves. Then, the odorscape is analyzed in the nerve centers by the mode of elemental processing or configural processing. The influences of background odor on insect target localization may be the results of the reciprocal addition, competitive binding or signal crosstalk of different odor molecules during the olfactory sensing and coding. At present, several kinds of green pest control technologies have been developed based on the odorscape management, such as insect behavior regulators, exogenous elicitors, breeding the crop varieties that can release resistant volatiles, “push-pull” technology and plant-mediated support system for natural enemies. In the future, it is necessary to further explore the behavioral, electrophysiological and neurological mechanisms of odorscape discrimination in insects, and optimize and integrate the green control technologies related to odorscape management, so as to build rational and efficient odorscape for insect pest control.

【Aim】To evaluate the toxicity and ecological risks of the formulations of seven neonicotinoid insecticides to the 7-spot ladybird, Coccinella septempunctata, so as to provide a reference for scientific use of neonicotinoid insecticides and protection of C. septempunctata.【Methods】The acute toxicity of the formulations of seven neonicotinoid insecticides, including 10% imidacloprid WP, 40% acetamiprid SP, 50% dinotefuran WP, 50% clothianidin WG, 40% imidaclothiz WG, 17% flupyradifurone SL and 25% thiamethoxam WG to the 2nd instar larvae of C. septempunctata was determined by using the method of residual film in glass tube, and the ecological risks of these insecticides were assessed. The solutions of the seven insecticides were prepared according to the maximum recommended field application rate, and sprayed on potted plants in the greenhouse to investigate the larval survival rate of C. septempunctata.【Results】The results of the indoor experiments showed that the acute toxicity of the seven neonicotinoid insecticides to the 2nd instar larvae of C. septempunctata was ranked in a descending order: 40% acetamiprid SP>40% imidaclothiz WG>10% imidacloprid WP>50% dinotefuran WP>50% clothianidin WG>25% thiamethoxam WG>17% flupyradifurone SL. The pot experiment in the greenhouse showed that the larval survival rates of C. septempunctata at 7 d after treatment with the seven insecticides at the maximum recommended field application rate were 10.00%-77.50%, and the highest larval survival rate of C. septempunctata was tested in the treatment with 25% thiamethoxam WG, while the lowest survival rate was observed in the treatment with 40% imidaclothiz WG. The results of ecological risk assessment showed that for a single application, the risk of 40% acetamiprid SP was unacceptable with the hazard quotient value in the farm (HQ_in) of more than 5, and those of the other pesticides were acceptable with the HQ_in values of less than 5. The hazard quotient values for crop or vegetable field outside the farm (HQ_{off crop or vegetable}) and for fruit tree garden outside the farm (HQ_{off fruit tree}) of these insecticides to C. septempunctata were less than 5, indicating that the risk is acceptable. After the second spray after 7 d, the risks of 40% acetamiprid SP and 50% dinotefuran WP were unacceptable with the HQ_in values of more than 5, and those of the other insecticides were acceptable with the HQ_in values of less than 5. The HQ_{off crop or vegetable} and HQ_{off fruit tree} values of the other insecticides except 40% acetamiprid SP were less than 5, indicating that the risks of these insecticides are acceptable.【Conclusion】Acetamiprid and dinotefuran should not be used twice continuously and be used in rotation in order to avoid harm to C. septempunctata.

The tomato leafminer, Tuta absoluta, is native to South America and a quarantine pest in the world nowadays, which can reduce the yield of the main host crop tomato by 80%-100% in severe cases. In over a decade, this insect pest has invaded and spread from its origin to almost the entire continent of Asia, Africa and Europe, becoming a major threat to the world tomato industry. T. absoluta was discovered in Ili, Xinjiang in 2017 and spread to Yunnan, Gansu and other regions in a short time, greatly threatening the healthy development of the tomato industry and other related agricultural industries in China. Internationally, sex pheromone-based monitoring, mass trapping and mating disruption control have become one of the important  measures to control T. absoluta. In order to study the efficient and environmentally friendly population dynamics monitoring and control technology of T. absoluta, we summarized the research and application status of the sex pheromone in mornitoring, early warning and control of T. absoluta in this article. The females of T. absoluta release sex pheromones to attract males to mate mainly in the morning, and adult mating reaches the peak at 7:00 a.m. In 1995 and 1996, the major and minor components of the sex pheromone released from T. absoluta and their synthetic methods were reported successively. The major and minor components of this sex pheromone are (3E, 8Z, 11Z)-tetradecatrienyl acetate (TDTA) and (3E, 8Z)-tetradecadienyl acetate (TDDA), respectively, which constitute the sex pheromone in a ratio of about 90∶10. Bioassay results revealed that TDTA had a strong attraction to males, which could be further enhanced when its mixture with TDDA was used. In recent years, more efficient and convenient synthetic methods of sex pheromone components have been developed, providing good conditions for their large-scale production and application. At present, the sex pheromone of T. absoluta has been widely used in the control of this insect pest in the world, and good results have been achieved. Among the reported sex pheromone traps commonly used for monitoring and mass trapping this insect pest, the water basin trap and triangle trap are more effective. The common doses of sex pheromone contained in commercial lure core are 0.5, 0.8 and 3.0 mg. For field application, the corresponding trap type and sex pheromone dose should be selected according to the actual situation of habitat and growth stage of crops, damage degree, local natural conditions, etc. In addition, the mating disruption by using sex pheromone is also common in the control of T. absoluta, and its successful application requires a highly enclosed environment. Because sex pheromone has the advantages of high efficiency, safety and environmental protection in the monitoring and control of T. absoluta, its related research results can provide important reference for the sustainable control strategies and measures of this insect pest in China.

【Aim】 The effects of chronic exposure to the sublethal concentration (LC₂₀) of dinotefuran on the growth and development of Sitobion avenae were studied in order to provide a theoretical basis for the scientific use of dinotefuran to control S. avenae and delaying the development of the resistance to the pesticide and extending the useful life of pesticide. 【Methods】 The LC₂₀ of dinotefuran to the 3rd instar nymphs of S. avenae was determined by using the leaf-dip method andusedforchronic exposure on S.
avenae for 15 generations. The resistance ratio of S. avenae to dinotefuran was determined, the developmental duration, reproduction and survival rates of S. avenae of two successive generations which were raised with wheat seedlings in test tube were recorded, and the body length, body width and body weight of adults of F₀ generation were measured. The differences in the body length, body width, body weight, survival rate, adult longevity and number of offspring produced between lowly resistant strain of various generations and the susceptible strain were analyzed by population specific life table and DPS software. 【Results】 After chronic exposure to LC₂₀ of dinotefuran for 15 generations, the resistance of S. avenae reached low level (6.54-fold). The developmental duration of the 2nd, 3rd and 4th instar nymph of F₀ generation of the lowly resistant strain was significantly longer than that of the susceptible strain, and the body length, body width and body weight of F₀ generation of adults of the lowly resistant strain were significantly increased, but the number of offspring produced per adult and adult longevity of F₀ generation of the lowly resistant strain were significantly reduced or shortened as compared to those of the susceptible strain. The adult survival rate, number of offspring produced per adult and adult longevity of F₁ generation of the lowly resistant strain were significantly reduced, the 2nd instar nymphal duration and nymphal duration of F₁ generation of the lowly resistant strain were significantly shortened as compared to those of the susceptible strain. The net reproductive rate (R₀), intrinsic rate of increase (R_m) and finite rate of increase (λ) of F₀ and F₁ generations of the lowly resistant strain were significantly lower than those of the susceptible strain, while the population doubling time (DT) of F₀ and F₁ generations and the mean generation time (T) of F₁ generation of the lowly resistant strain were significantly prolonged as compared to those of the susceptible strain. 【Conclusion】 Chronic exposure to LC₂₀ of dinotefuran results in the increase in the resistance of S. avenae to dinotefuran and individual size of adults of F₀ generation, while inhibits the longevity and fecundity of F₀ and F₁ generations of S. avenae.
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 Insects are the most abundant and widespread group of animals in the world that harbor complex and diverse gut microbes. Different insects differ in gut structure, gut environment, edibility, age and external environment, and the composition and abundance of gut microbes also show difference. Insect gut microbes are mainly transferred vertically and horizontally between populations and individuals, and play a vital role in nutrient metabolism, physiological behaviour, defence, detoxification and many other functions in insect hosts. Insect gut microbes can be isolated from culture media by in vitro culture methods and rapidly identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and sequencing technologies such as 16S rRNA gene sequencing. The combination of metagenomics, proteomics, metabolomics and other omics technologies makes the identification and functional prediction of gut microbes more efficient. Microbial functions can be more accurately verified by in vitro experiments, microbial supplementation, microbiota transplantation and silencing of genes associated with microbial members. Sterile insects can be obtained by high temperature treatment, lysozyme treatment, sterile feeding and antibiotic treatment for functional verification experiments. However, the most widely used antibiotic method still has limitations in application. By exploiting the characteristics of gut microbes, genetic engineering of symbiotic bacteria can be used to control pests and insect-borne infectious diseases. At present, insect gut microbes play an important role in the fields of ecology, economy, energy and environmental protection. With the development and integration of new technologies, more insect-microbe interaction mechanisms will be revealed, and pest control methods through insect gut microbes will become more diverse, environmentally friendly and efficient.

【Aim】 Altitudinal gradient has an important impact on the distribution and maintenance of insect species. This study aims to provide a theoretical basis for studying the impact of altitudinal gradient on insect distribution by exploring the variation law and distribution characteristics of species diversity of rove beetles at different altitudinal gradients in the reserve.【Methods】From May 2020 to April 2021, three kinds of passive acquisition devices, flight interception trap, Malaise trap and pitfall trap, were used in Mangshan National Nature Reserve, Hunan Province, Central China to investigate the species of rove beetles at the altitudinal gradients of 500-800 m (Ⅰ), 800-1 100 m (Ⅱ), 1 100-1 400 m (Ⅲ) and 1 400-1 700 m (Ⅳ), and the species diversity, community structure similarity and species abundance of rove beetles at different altitudinal gradients were analyzed using Excel 2016 and past 3.【Results】From May 2020 to April 2021, we collected and recorded 2 135 rove beetles in Mangshan National Nature Reserve, Hunan Province, belonging to 9 subfamilies, 45 genera and 111 species, of which the number of species in Staphylininae was the most (25 genera and 63 species), and the numbers of species in Steninae and Oxytelinae were the least (both 1 genus and 1 species). The Shannon-Wiener diversity index, Mangalef richness index, Berger-Parker dominance index and Pielou’s evenness index of rove beetles were 3.8280, 2.3920, 0.1217 and 0.4140, respectively. There were differences in species diversity indexes of rove beetles at different altitudinal gradients. The species number, individual number, Shannon-Wiener diversity index and Margalef richness index of rove beetles at the altitudinal gradient Ⅲ were significantly higher than those at the altitudinal gradient Ⅰ. The species of rove beetles were poor and the dominant species were prominent at the altitudinal gradient Ⅰ, but the community structure was relatively stable. Altitudinal gradient Ⅱ was the transition gradient from low altitude to medium altitude. The species of rove beetles were rich, the community structure was complex, the dominant species were prominent and concentrated, and the community structure was relatively unstable at the altitudinal gradient Ⅲ. The species of rove beetles at the altitudinal gradient Ⅳ were relatively poor as compared with those at the altitudinal gradient Ⅲ. The similarity coefficient between the altitudinal gradient Ⅲ and altitudinal gradient Ⅳ was the highest, showing medium similarity, while those between other altitudinal gradients showed medium dissimilarity.【Conclusion】 The results of this study suggest that there are great differences in the distribution characteristics of rove beetles among different altitudinal gradients. Rove beetle species are poor and the community structure is single in low altitude areas. The medium altitude area is rich in rove beetle species, and has complex community structure and prominent dominant species. Compared with the medium altitude area, the high altitude area is relatively poor in rove beetle species. The similarity coefficient of rove beetle species between the medium-high altitude area and the high altitude area is the highest.

The South American tomato pinworm, Tuta absoluta, is a worldwide devastating pest on tomatoes. This insect pest invaded China in 2017 and showed a trend of spread, posing a serious threat to tomato production in China. Unreasonable use of insecticides for control of this insect pest has led to the increasing level of resistance and the decrease of control efficacy. Consequently, there is an urgent need to develop novel green control technologies. Physical control trapping technique and olfactory behavior manipulation technique are important components of the integrated pest management program. In this article, the research progress of physical control trapping (light traps and color traps) and olfactory behavior manipulation (sex pheromone and plant volatiles) in T. absoluta were summarized. Color significantly affects the trapping efficiency of pheromone traps and sticky color traps. White, black and blue traps attract more T. absoluta adults in the field. The black light traps and LED traps with the wavelength of 470 nm have the best trapping efficiency on T. absoluta, and also have synergistic effects on sex pheromone. The sex pheromone of T. absoluta includes the major component (3E, 8Z, 11Z)-tetradecatrienyl acetate and the minor component (3E, 8Z)-tetradecadienyl acetate, in a ratio of ~9∶1. The optimal trapping blend for mass trapping is (3E, 8Z, 11Z)-tetradecatrienyl acetate and (3E, 8Z)-tetradecadienyl acetate in a ratio of 95∶5, and delta traps with sex pheromone lure show the highest trapping efficiency in comparison with other trap types. The sex pheromone of T. absoluta has been widely used for monitoring, mass trapping and mating disruption. Plant volatiles and traditional food attractant volatiles affect the host selection and oviposition of T. absoluta. Octyl acetate, phenylacetaldehyde+acetic acid blend, acetic acid+3-methyl-1-butanol blend, and a blend consisting of limonene, β-ocimene, α-terpinene, δ-elemene and (E)-β-caryophyllene show attractive activities to T. absoluta. p-Quinone, 2-carene, d-curcumene and 1,2-diethylbenzene in tomato can serve as oviposition stimulants to T. absoluta. By contrast, 1-fluorododecane, caryophyllene, curcumene, elemene, humulene, zingiberene, tridecan-2-one, undecan-2-one, (Z)-3-hexenyl propanoate and methyl salicylate have adverse effects on host selection, oviposition or growth and development of T. absoluta. Finally, current problems of behavioral manipulation techniques of T. absoluta, such as unclear mechanisms, unstable effects, and lack of combined application technology with other green control strategies, were discussed, and potential research directions were prospected, which will provide a reference for the development of green control technologies based on insect behavioral manipulation in this pest.

【Aim】 To sequence and analyze the complete mitochondrial genome (mtgemome) of Campsiura mirabilis, and to discuss the phylogenetic relationship of the family Scarabaeidae based on mtgenome sequences. 【Methods】 The whole mtgenome of C. mirabilis was firstly sequenced on the Illumina Hiseq X Ten platform, and the gene structure characteristics and base composition of the C. mirabilis mtgenome were analyzed. Combined with the 54 mtgemome sequences published in GenBank, the selection pressure of protein-coding genes (PCGs) in the mtgenome of 55 species in Scarabaeidae was analyzed. The phylogenetic tree of Scarabaeidae was constructed with Lucanus mazama in Lucanidae as the outgroup based on PCG and rRNA gene sequences using maximum likelihood (ML) and Bayesian inference (BI) methods. 【Results】 The full-length of the C. mirabilis mtgenome (GenBank accession no.: MT548771) is 16 123 bp, including 13 PCGs, 22 tRNA genes, 2 rRNA genes and a Dloop region (control region), without gene rearrangement. All the 22 tRNA genes show the typical cloverleaf secondary structure except for the absence of DHU arm of trnS1. The base composition of the mtgenome of C. mirabilis shows a higher AT content with the positive AT-skew and negative GC-skew. The K_a/K_s values of PCGs of Scarabaeidae are all less than 1, indicating that all of these 13 PCGs have experienced purifying selection. The phylogenetic relationship in Scarabaeidae based on the sequences of the 13 PCGs and 2 rRNA genes was: ((Aphodiinae+Scarabaeinae)+(Melolonthinae+(Cetoniinae+(Rutelinae+Dynastinae)))). 【Conclusion】 In this study we sequenced and analyzed the mtgenome of C. mirabili, and analyzed the phylogenetic relationship of Scarabaeidae. Our results indicate that the subfamilies of Scarabaeinae, Cetoniinae, Rutelinae, Dynastinae and Melolonthinae are monophyletic groups.

【Aim】Adipokinetic hormone (AKH), a type of neuropeptide, plays central roles in regulating development and behavioral events in diverse insects. Investigating the functions of AKH on the growth and development of Bactrocera dorsalis larva will contribute to a better understanding of the conservation and functional diversity of neuropeptides in insects, and may shed light on evaluating the potential of AKH signal system as the target of novel insect control agents. 【Methods】The full-length cDNA sequence of BdAKH of B. dorsalis was cloned, and characterized with bioinformatics methods. The expression levels of BdAKH in different developmental stages (egg, 1st-3rd instar larvae, pupa, virgin female adult and male adult), and different tissues ［central nervous system, corpora cardiaca/corpus allatum (CC/CA), fat body, Malpighian tubules, midgut, hindgut, cuticle, ovary, testis and hemocytes］ of the late 3th instar larva of B. dorsalis were detected by qPCR. Immunohistochemistry technique was used to localize the neurons expressing BdAKH in the 3rd instar larva of B. dorsalis. RNAi combined with biological observation was used to analyze the regulation of BdAKH on the growth and development of B. dorsalis larva.【Results】The full-length cDNA sequence of BdAKH (GenBank accession no. KY073319) of B. dorsalis was cloned. This cDNA of 572 bp contains an open reading frame (ORF) of 252 bp, which encodes 83 amino acid residues. BdAKH of B. dorsalis has conserved structure that consists of one mature peptide (QLTFSPDWamide). The expression levels of BdAKH were higher in adult. BdAKH was mainly expressed in the CC/CA of the late 3rd instar larva. Compared with the control group (dsGFP), BdAKH knockdown in the 3rd instar larva of B. dorsalis caused a delay in pupation and decreased pupation rate, while the pupal weight and phenotype had no remarkable difference. 【Conclusion】AKH plays important roles in regulating the larval growth and development of B. dorsalis, which could be viewed as new targets of novel insect control agents.

【Aim】The aim of this study is to lay a foundation for the gene expression analysis of Acyrthosiphon pisum by identifying the expression stablility of reference genes in A. pisum under different experimental conditions. 【Methods】The expression levels of 14 candidate reference genes commonly used in insects (EF1α, Tubulin, NADH, RPL12, SDHB, 18S rRNA, 28S rRNA, 16S rRNA, ATPase, Actin, TATA, RPL32, GAPDH and RPL7)in different developmental stages (1st-4th instar nymphs and adult), winged and wingless parthenogenetic adults, different tissues (head, thorax and abdomen) of parthenogenetic wingless adults, parthenogenetic wingless adults of different geographical populations (American population, Gansu population, Yunan population and Delingha population), parthenogenetic wingless adults fed on different host plants (alfalfa, clover and broad bean), parthenogenetic wingless adults reared under different photoperiods (24L∶0D, 0L∶24D and 16L∶8D), parthenogenetic wingless adults reared under different temperatures (4, 18 and 35 ℃) and parthenogenetic wingless adults treated with 200 g/L imidacloprid were detected by qPCR. The expression stability of the above 14 reference genes was evaluated using RefFinder, ΔCt method, GeNorm, NormFinder, and BestKeeper. Using CYP6CY3 as the target gene to explore the influence of different reference genes on its expression level analysis in parthenogenetic wingless adults treated with 200 g/L imidacloprid. 【Results】 18S rRNA and GAPDH were recommended as the most stably expressed reference genes, whereas 16S rRNA and Actin showed the least expression stability under biotic conditions (developmental stage, wing morph, tissue, geographical population and host plant) through comprehensive analysis for the results of ΔCt method, GeNorm, NormFinder and BestKeeper by RefFinder, based on the qPCR results. Meanwhile, 18S rRNA and EF1α were recommended as the most stably expressed reference genes, while Tubulin and TATA showed the least expression stablility under abiotic conditions (photoperiod, temperature and insecticide). According to the GeNorm analysis data of the optimal number of reference genes and analysis of the influence of different reference genes on the expression of target gene CYP6CY3, 18S rRNA and EF1α were recommended as the most stably expressed reference genes for further studies in A. pisum. 【Conclusion】It is recommended to use the combination of 18S rRNA and EF1α in qPCR analyses in A. pisum.

【Aim】This study aims to preliminarily clarify the joint action mechanism of ethyl formate (EF) and methyl isothiocyanate (MITC) to Acanthoscelides obtectus through analyzing the transcriptome data of A. obtectus fumigated with EF, MITC and EF+MITC.【Methods】The A. obtectus adults were treated with fumigation of EF(22.398 μL/L), MITC(0.854 μL/L) and EF+MITC(14.764 μL/L) through wild-mouth bottle fumigation method. The control group (CK) was not fumigated. Transcriptome sequencing of the A. obtectus adults treated with fumigation of EF, MITC and EF+MITC was performed with Illumina Hi Seq^TM 4000 sequencing platform. GO classification and KEGG enrichment analysis were performed on differentially expressed genes (DEGs). Six DEGs were selected for RT-qPCR validation.【Results】 There were 171 and 293 DEGs in the CK vs EF and CK vs MITC comparative groups, respectively, and most of them were up-regulated. However, the number of DEGs in the CK vs EF+MITC comparative group was 1 745, and most of them were down-regulated. GO classification of DEGs showed that DEGs in the  CK vs EF and CK vs MITC comparative groups were mainly enriched in cellular anatomical entity, binding, and catalytic activity, while those in the CK vs EF+MITC comparative group were mainly enriched in cellular anatomical entity, binding, and cellular process. KEGG pathway enrichment analysis of DEGs showed that DEGs in the CK vs EF comparative group were mainly enriched in pathways of protein digestion and absorption, lysosome and protein processing in endoplasmic reticulum, those in the CK vs MITC comparative group were mainly enriched in pathways of focal adhesion, ECM-receptor interaction and insect hormone biosynthesis, and those in the CK vs EF+MITC comparative group were mainly enriched in RNA transport, DNA replication and mismatch repair. In addition, the expression levels of two and three detoxification enzyme genes in A. obtectus adults in response to EF and MITC fumigation treatments were significantly down-regulated, respectively, however, the expression levels of five detoxification enzyme genes in A. obtectus adults in response to EF+MITC fumigation treatment were significantly down-regulated as compared with those in the CK. The expression trends of the six selected DEGs were basically consistent with the transcriptome data.【Conclusion】The results of this study indicate that the combination of EF and MITC has a synergistic effect, which can induce cell genotoxic damage in A. obtectus. The inhibition of expression of detoxification enzyme genes seems to be the main reason for its synergistic effects. In this study, the molecular mechanism of fumigation and insecticidal effect of the mixture of EF and MITC on A. obtectus was preliminarily clarified, which provides an important basis for the further study on the combined action mechanism of EF and MITC on A. obtectus.

 【Aim】To establish the antennal transcriptome database of the Pieris rapae adult, so as to deeply mine the gene data of P. rapae by using bioinformatics and molecular biology methods.【Methods】High-throughput sequencing platform Illumina NovaSeq 6000 was used to perform antennal transcriptome sequencing, sequence assembly, functional annotation and differentially expressed gene analysis of P. rapae adults. qRT-PCR was used to verify nine differentially expressed olfaction-related genes including PrapOR1, PrapOR2, PrapOR5, PrapOBP1, PrapOBP4, PrapOBP5, PrapSNMP1, PrapSNMP2 and PrapSNMP3.【Results】By sequencing of the antennal transcriptome of adults of P. rapae, a total of 17.65 GB sequencing data (NCBI registration number: PRJNA869896) were obtained. A total of 116 317 transcripts were obtained through filtering and sequence splicing. Then, 43 390 unigenes were obtained by Corset hierarchical clustering. BUSCO evaluation showed that the stitching quality had good integrity and high accuracy. The databases with the largest number of unigene annotations in a descending order were NT, NR, Pfam, GO, Swiss-Prot, KEGG and KOG/COG. Furthermore, 176 olfaction-related genes were screened by gene functional annotation analysis, among them 19 genes were differentially expressed, including 15 genes highly expressed in female adult antennae and four genes highly expressed in male adult antennae. qRT-PCR verification results showed that PrapOR1 and PrapOR2 were highly expressed in male adult antennae, PrapOR5, PrapOBP1, PrapOBP4, PrapOBP5, PrapSNMP1, PrapSNMP2 and PrapSNMP3 were highly expressed in female adult antennae, indicating the consistency with the transcriptome sequencing results.【Conclusion】In this study, a transcriptomic database of adult antennae of P. rapae was established, the olfaction-related genes were screened and the differential expression of olfaction-related genes was analyzed. The results provide a theoretical basis for further studies on the gene function and olfactory molecular mechanism of P. rapae.

 Unmovable cultural relics are important physical materials that reflect the development of social productivity and social life in the past. They are important research objects for cultural relics, with extremely high historical, artistic and scientific values. Unmovable cultural relics suffer from various deterioration effects for being outdoors. Biodeterioration caused by pests is one of the important reasons for cultural relics damage. Among unmovable cultural relics, ancient buildings, murals and earthen sites are particularly affected by insect pests. According to the classification of cultural relics, we expounded on the main types and mechanisms of insect pests in ancient buildings, murals and earthen sites, and summarized the current methods of pest control in these cultural relics in this article. Physical and chemical control methods are traditionally used to prevent and control pests in cultural relics. The chemical methods are rapid and highly effective ways to kill insects, but chemical agents have brought great pollution to the ecological environment, and the vulnerability of cultural relics restricts the use of chemical insecticides. At present, many long-acting and environment-friendly green insecticides have greatly improved traditional chemical methods. In addition, biological control methods that use biological natural enemies or parasitic organisms to control pests not only have small impacts on the ecosystem but also have a long-lasting effect, which is a hotspot in research on new pest control. However, whether the new species used to control the pests will do harm to cultural relics needs to be further studied. Pest control of cultural relics is a cross-research field, and the methods in architecture, agriculture and other fields have great enlightening significance and reference value. Finally, we discussed and prospected the current situation of common pest control research of unmovable cultural relics, hoping to provide a reference for the research of pest control in cultural relics.

 A stable intestinal microbial internal environment is the result of the interaction between intestinal microbes and intestinal immune response. During the continuous feeding, the species and number of insect intestinal microbes constantly change, so a complex and dynamic homeostatic mechanism is formed between intestinal microbes and intestinal epithelial cells. Insect intestinal epithelial cells can sense beneficial and harmful conditions and use immunoregulatory pathways for dynamic regulation of microbial population homeostasis, such as the dual oxidase-reactive oxygen species (Duox-ROS) system and immunodeficiency (Imd) signaling pathways, which can sense the changes in the number of intestinal microbies and participate in the regulation of intestinal microbial homeostasis. In addition, the intestinal microbes can also indirectly play a role in homeostatic regulation by releasing corresponding effectors to regulate the behavior of the flora through quorum sensing (QS). Thus, in this article, we reviewed the roles of physical defense, immune signaling pathways and QS in the maintenance of insect intestinal microbial homeostasis, which will deepen the understanding of the interactions between intestinal tissues and intestinal microbes. In the future, we will continue to reveal the regulatory mechanisms of microbial homeostasis in more species of insects and the relationship between the regulatory mechanisms. In addition, new pesticides will be designed and developed to alter the homeostasis of intestinal microbes based on the regulatory mechanisms, which will provide new targets and ideas for the pest control.

Eusocial insects, such as bees, ants and wasps of the Hymenoptera and termites of the Blattodea, have significant diversity in morphology, behavior and life cycle, although their genetic background and genetic basis are consistent in a population. Most eusocial insects show different caste structure and life span differentiation. In these structure, queens tend to have a longer life span than workers, and their reproductive capacity is only owned by one queen or several queens, while the other members of the group can only act as workers. However, in some species, the caste structure has certain plasticity, and individuals can switch from one caste or behavioral phenotype to another according to specific environmental clues. Due to the common genetic background between different castes, the diversity of eusocial insect populations is largely caused by the gene transcriptional differences between individuals. This means that epigenetic mechanisms characterized by modifying gene expression without changing the gene sequence may play an important role in eusocial insects. Evidence had shown that epigenetic regulatory mechanisms such as DNA methylation or RNA methylation, histone post-translation modification and non-coding RNA had been proven to affect eusocial insects in many aspects, such as caste structure, longevity differentiation and aging. In this article, we reviewed the research progress of these epigenetic regulatory mechanisms and their different roles in insects, so as to deepen the understanding and cognitive degree of the origin and behavior evolution of eusocial insects. In the future, epigenetic regulatory mechanisms have potential application value in the research and development of anti-aging drugs, treatment of aging-related diseases, and slowing down the aging process of organisms.

【Aim】 To explore the molecular characteristics, expression patterns and biological function of the E3 ubiquitin ligase gene NlHECTD2 of Nilaparvata lugens.【Methods】 Based on the transcriptome data of N. lugens, the full-length cDNA sequence of NlHECTD2 was cloned by PCR and bioinformatically analyzed. qRT-PCR was used to detect the expression levels of NlHECTD2 in the egg, 1st-5th instar nymphs, female adult newly emerged within 24 h and 1-5-day-old female adults, and the head, throax, abdomen, gut and ovary of the 3-day-old female adult of N. lugens. A single newly emerged female adult of N. lugens was injected with 0.05 μL dsNlHECTD2 (5 000 ng/μL) and the expression level of NlHECTD2 was detected by qRT-PCR at 24, 48, and 72 h after RNAi, and the number of yeast-like symbionts (YLSs) in the hemolymph, survival rate of the female adult of N. lugens, number of eggs laid per female and egg hatching rate were also detected.【Results】 The full-length cDNA sequence of NlHECTD2 (GenBank accession number: XM_039427060.1) was successfully cloned from N. lugens. The open reading frame (ORF) of NlHECTD2 is 2 850 bp in length and encodes 950 amino acids. NlHECTD2 has no signal peptide and contains a C-terminal catalytic domain with a subclass ubiquitin ligase (E3). Phylogenetic analysis indicated that NlHECTD2 was clustered together with other hemipteran HECTD2s, and had the highest homology with HECTD2 of Bemisia tabaci. The qRT-PCR results showed that NlHECTD2 had obvious spatiotemporal expression specificity, with the highest expression level in the abdomen of the 3-day-old female adult of N. lugens. The RNAi results showed that compared with the control (injected with dsGFP), injection of dsNlHECTD2 significantly inhibited the expression level of NlHECTD2 and extremely significantly decreased the number of YLSs in the hemolymph of N. lugens, which led to an extremely significant decrease in the survival rate of female adult, number of eggs laid per female and egg hatching rate of N. lugens.【Conclusion】 NlHECTD2 is closely related to the process of YLS release to hemolymph in N. lugens, plays an important role in the growth, development and reproduction of N. lugens, and can be used as a potential target for the control of N. lugens.

【Aim】To explore the effects of bone morphogenetic protein (BMP) signal on the phagocytosis of Drosophila melanogaster plasmatocytes. 【Methods】The UAS-Gal4 system of D. melanogaster was used to specifically knock down BMP signal-related genes Dpp, Gbb, Tkv, Put, Med, Wit, Sax, Mad, Dad, Sal, Brk and Omb in plasmatocytes. The phagocytic indexes of plasmatocytes were calculated to analyze the phagocytic capacities of plasmatocytes after injecting non-pathogenic fluorescence-conjugated microspheres (FluoSphere Microspheres), pHrodo-labeled Gram-negative bacterium Escherichia coli (pHrodo-Escherichia coli) and pHrodo-labeled Gram-positive bacterium Staphylococcus aureus (pHrodo-Staphylococcus aureus) into the 3rd instar larva and adult of D. melanogaster. 【Results】 In the plasmatocytes of the 3rd instar larva of D. melanogaster, knocking down the expression of Dpp, Gbb, Tkv, Wit, Dad, Brk and Omb significantly reduced the phagocytic indexes to FluoSphere Microspheres, while knocking down Dpp, Gbb, Tkv, Wit, Dad and Brk significantly impaired the phagocytic capacity to pHrodo-Escherichia coli, compared with control group Cg>w¹¹¹⁸. In addition, the ability of plasmatocytes to phagocytize pHrodo-Staphylococcus aureus decreased obviously after knocking down Gbb compared with control group Cg>w¹¹¹⁸. Moreover, in adults, we found that the total phagocytic capacity of plasmatocytes decreased obviously upon knocking down Gbb and Dad, whereas after the knockdown of Put, the total phagocytic capacity of plasmatocytes increased. 【Conclusion】In the D. melanogaster larvae, Dpp, Gbb, Tkv, Wit, Dad, Brk and Omb positively regulate the phagocytosis of plasmatocytes. Dpp, Gbb, Tkv, Wit, Dad and Brk promote the phagocytosis of plasmatocytes to Gram-negative bacteria, while Gbb promotes the phagocytosis of plasmatocytes to Gram-positive bacteria. In the D. melanogaster adults, Gbb and Dad contribute to the phagocytosis of total plasmatocytes, while Put negatively regulates the phagocytosis of plasmatocytes.

【Aim】To observe the ovarian developmental progress and formulate ovarian developmental grading criteria of Conopomorpha sinensis, explore the influence of mating on the ovarian developmental progress and fecundity. 【Methods】 The newly eclosed female and male adults of C. sinensis were paired in a 1∶1 ratio and reared. The female ovaries were dissected daily, and the mating experience was judged according to the characteristics of the bursa copulatrix. The characteristics of fat body, length of ovarioles, total number of egg chambers and number of mature eggs of mated and unmated females were recorded for grading the ovarian development progress. The newly eclosed female and male adults paired in a 1∶1 ratio, and newly eclosed female adults that were individually reared were used as the mated group and unmated group, respectively, and the pre-oviposition period, oviposition period, number of eggs laid per female and female adult longevity were counted in the two groups.【Results】 The ovarian development of C. sinensis could be divided into five stages, including yolk deposition prophase (stage Ⅰ), yolk deposition phase (stage Ⅱ), egg maturation phase (stage Ⅲ), peak phase of oviposition (stage Ⅳ) and terminal phase of oviposition (stage Ⅴ). Only the ovaries of the mated female adults could completely develop. Otherwise, the ovaries of the unmated female adults only developed into the yolk deposition phase (stage Ⅱ). The preoviposition period, oviposition period, number of eggs laid per female and female adult longevity in the mated group were 3.82 d, 11.23 d, 176.42 grains and 16.35 d, respectively. The female adults in the unmated group could not lay eggs for life, and the female adult longevity in the unmated group was 20.48 d. 【Conclusion】 The ovarian development of C. sinensis adults can be divided into five stages. However, mating is a prerequisite for the completion of ovarian development of the female adult. The ovarian development of the unmated female adults terminates after reaching stage Ⅱ. The fecundity of the mated female adults is significantly higher than that of the unmated females, and the unmated females can not lay any eggs for life.

【Aim】 To clarify the defense mechanism of Ostrinia furnacalis against cadmium and chlorantraniliprole, and to evaluate the cumulative effects of heavy metals and pesticide pollution on insects. 【Methods】 The newly hatched larvae of O. furnacalis were fed with the artificial diet containing 5 mg/kg cadmium, 0.003 mg/kg chlorantraniliprole and 5 mg/kg cadmium+0.003 mg/kg chlorantraniliprole, respectively, and those fed with the normal artificial diet were used as the control. The developmental duration, body weight, adult emergence rate and abnormal pupal rate were recorded, and the activities of detoxification enzymes including glutathione-S-transferase (GST), carboxylesterase (CarE) and acetylcholinesterase (AChE) in O. furnacalis at different developmental stages (3rd instar larva, female and male pupae, and female and male adults) were detected. 【Results】 Cadmium (5 mg/kg), chlorantraniliprole (0.003 mg/kg), and their combined treatment (5 mg/kg cadmium+0.003 mg/kg chlorantraniliprole) had effects on the growth and development of O. furnacalis. In chlorantraniliprole treatment group, the larval duration of O. furnacalis was the longest, significantly prolonged by 7.1 d as compared to that in the control group, and the pupal weight, adult weight and adult emergence rate of O. furnacalis were the lowest, significantly decreased by 9.1 mg, 2.4 mg and 25.5% as compared with those in the control group. In cadmium+chlorantraniliprole treatment group, the larval duration of O. furnacalis was 4.9 d shorter than that in chlorantraniliprole treatment group, and the abnormal pupal rate was the highest, significantly increased by 19.4% as compared to that in the control group. The adult duration of O. furnacalis in cadmium+chlorantraniliprole treatment group was the shortest, significantly reduced by 1.6 d as compared to that in the control group. Cadmium, chlorantraniliprole and cadmium+chlorantraniliprole had effects on the detoxification enzyme activities in O. furnacalis. Compared with the control, cadmium, chlorantraniliprole and cadmium+chlorantraniliprole showed inducing effects on the GST activities in the 3rd instar larvae, female and male pupae and male adults of O. furnacalis, and the GST activities in different developmental stages of O. furnacalis in cadmium+chlorantraniliprole treatment group were significantly higher than those in the other treatment groups and the control group. Compared with the control, cadmium, chlorantraniliprole and cadmium+chlorantraniliprole showed inhibitory effects on the CarE activities in different developmental stages of O. furnacalis, and the cadmium+chlorantraniliprole treatment had the strongest inhibitory effect on the CarE activities in various developmental stages of O. furnacalis. Compared with the control, cadmium, chlorantraniliprole and cadmium+chlorantraniliprole showed inducing effects on the AChE activity in the 3rd instar larvae of O. furnacalis, but had different effects on the AChE activities in the pupae and adults. 【Conclusion】 Cadmium (5 mg/kg), chlorantraniliprole (0.003 mg/kg) and their combined treatment can all affect the growth and development of O. furnacalis, and have different effects on its detoxification enzyme activities.

【Aim】Grapholita molesta is an important and frequent pest of fruit trees. This study aims to investigate the roles of light intensity on the oviposition preference of G. molesta, and to further reveal the dim-light vision ability in G. molesta. 【Methods】The numbers of eggs of G. molesta laid on leaves on the sunny side and shaded side in the peach tree canopy were investigated in spring, summer and autumn, and the difference in light intensity between the sunny side and shaded side at sunset was measured. Light-dark two-choice experiments were carried out indoor to test the oviposition preference behavior response of G. molesta adults to light intensity. 【Results】 In spring, summer and autumn, G. molesta adults preferred to lay eggs on leaves on the sunny side in the peach tree capony with significantly higher light intensity, the numbers of eggs laid on the sunny side were 4.24, 9.30 and 5.82 times as high as those on the shaded side, respectively. In the light-dark two-choice experiments, G. molesta adults preferred to lay eggs to light than to dark, with the oviposition selection rates of 87.48%, 83.68%, 82.92%, 80.08% and 84.84%, respectively, under 10 000, 100, 1 and 0.01 lx and natural light conditions. The oviposition preferences between to strong light and to weak light revealed that when the light contrast (strong light/weak light) was 10 and 2, respectively, G. molesta adults showed a preference to strong light under 10 000, 100, 1 and 0.01 lx and natural light conditions. Moreover, this preference to strong light did not decrease significantly with the decrease of light intensity, and the oviposition selection rates were higher than 75%.【Conclusion】 Light intensity can affect the oviposition preference of G. molesta adults. Female adults show obvious oviposition preference to strong light, and can still discriminate well the difference in light intensity even under dim light, exhibiting a well dim-light vision ability. The results provide a basis for new physical trapping techniques based on visual behavior regulation.

【Aim】By clarifying the difference in the temperature adaptability of the main biological characters between two closely related species of corn borers, the Asian corn borer (Ostrinia furnacalis) and European corn borer (O. nubilalis)， living in the only one sympatric region in the world and accompanied by fierce interspecific competition， this study aims to reveal the biological driving mechanism of the rapid replacement of O. nubilalis population by O. furnacalis in the sympatric region in Xinjiang, Northwest China.【Methods】 At 15, 20, 25, 30 and 35 ℃, the egg duration, egg mass hatching rates, egg hatching rates per egg mass and mortalities of egg masses of the O. furnacalis and O. nubilalis populations isolated from the same region in Xinjiang, and at 20, 25, 30 and 35 ℃, their adult longevity, pre-oviposition period, oviposition period, numbers of eggs laid per female, larval and pupal duration, larval and pupal weight etc. were measured and compared. 【Results】 The results showed that the mortalities of egg masses of O. nubilalis were significantly higher than those of O. furnacalis at 15, 20, 25 and 35 ℃, and the average egg hatching rates per egg mass of O. nubilalis were significantly lower than those of O. furnacalis at 20, 25, 30 and 35 ℃. Furthermore, the hatching ability of egg masses of O. nubilalis decreased significantly with the increase of temperature, until the temperature increased to 35 ℃, the mortality of egg masses was the highest (73.42%±2.28%) and the average egg hatching rate per egg mass was the lowest (48.46%±2.64%), while those of O. furnacalis were 41.88%±4.33% and 67.99%±2.52%, respectively. At the same temperature, there was no significant difference in the pre-oviposition period, female adult longevity, male adult longevity and oviposition period between sympatric O. furnacalis and O. nubilalis. However, the main fecundity indexes of O. nubilalis, such as the number of egg masses laid per female, average number of eggs per egg mass laid by a single female and average number of eggs laid per female, were significantly lower than those of O. furnacalis. Compared with O. furnacalis, O. nubilalis had significantly heavier 1st-4th instar larval weight at the low temperature of 20 ℃. However, at higher temperatures (30 and 35 ℃), the 2nd and 3rd instar larval weight of O. nubilalis was significantly lighter than that of O. furnacalis and the duration of various instar larvale and pupal duration of O. nubilalis showed no significant difference from those of O. furnacalis. 【Conclusion】Compared with O. nubilalis, O. furnacalis has better temperature adaptability. Especially at high temperatures (30 and 35 ℃), O. furnacalis has higher survival rate of egg masses, better hatching ability, higher fecundity and heavier body weight, showing stronger competitiveness.

 【Aim】 To explore the sequence characteristics of WntA-encoding protein in the Wnt gene family of Locusta migratoria manilensis and its spatiotemporal expression profile during the embryonic development, and lay a foundation for the further functional research of LmmWntA and mining other Wnt gene family members of L. migratoria manilensis. 【Methods】 The Wnt gene family gene LmmWntA of L. migratoria manilensis was cloned by PCR and identified by neighbor-joining (NJ) method. The amino acid sequence characteristics of LmmWntA were analyzed by homologous sequence multiple alignment. Whole-mount in situ hybridization was used to screen the transcriptional signals of LmmWntA in 17 consecutive embryonic developmental stages of L. migratoria manilensis after egg laying (AEL) to 12, 24, 35, 46, 56 and 65 h, and 3, 3.5, 4, 4.5, 5, 5.5, 6.5, 8, 8.5, 9.5 and 11 d. 【Results】 The full-length CDS of LmmWntA (GenBank accession number： MW052768) of L. migratoria manilensis was cloned and is 1 101 bp, encoding 336 amino acids. LmmWntA and WntA proteins of cephalochordates, insects, clawed animals and annelids were clustered into a monophyletic group of WntA subfamily. The middle region and C-terminus of LmmWntA maintain high homology with the WntA protein sequences of the corresponding species, except for the difference in the N-terminal signal peptide region, and LmmWntA was clustered with the AmWntA protein of Apis mellifera in Hymenoptera as a sister group with the amino acid sequence identity of 59.05%. LmmWntA was first expressed in the terminal growth region of the 35 h AEL and continued to be expressed in this region until the 4 d AEL, forming stripe expression in the abdomen of each segment of the neonatal segment, and continued to be expressed in the posterior half of the optic lobe, which develops into compound eyes in the future, from the 46 h AEL to the 8.5 d AEL of L. migratoria manilensis. LmmWntA was continuously expressed in the brain from the 56 h AEL to the 5.5 d AEL. At the 65 h AEL, the stripe-like expression signal of LmmWntA in each segment of the abdomen was gradually transferred to both sides of the midline of the abdomen, and there was a clear expression signal at the base of the antennae. At the 5.5 d AEL, the expression signal of LmmWntA was further transferred to the abdominal nerve. From the 3 d AEL, LmmWntA was expressed at the distal end of the ventral somite, and later transferred to the palate, foot joint and end. As the end of the 4.5 d AEL embryo began to invaginate to form proctodeum, LmmWntA was expressed in the ventral and anterior end of the invaginated proctodeum, and most of them invaginated to the 7th somite of the abdomen. At the 9.5 d AEL, LmmWntA was expressed at the wing germ disc. 【Conclusion】 LmmWntA was dynamically expressed during the embryonic development of L. migratoria manilensis, speculating that LmmWntA is involved in the development and formation of important tissues and organs such as the posterior segment growth of embryo, nervous system (brain and abdominal nerve), compound eye, antennae, posterior end of digestive system (proctodeum), jaw, chest appendages (leg and wing) of L. migratoria manilensis. The results of this study lay the foundation of developmental biology for further research on LmmWntA deficiency.

 Honeybee queens share the same genetic background with the workers, and they both are developed from fertilized eggs. Nutritional and spatial variances during the development lead to significant morphological, physiological and behavioral dimorphism between the two castes. The insulin signaling pathway (IIS) regulates the behavior of worker bees, thus influencing their longevity. Longer longevity of queen bees is associated with increased oxidative stress and enhanced stress defense. Vitellogenin (Vg) interacts with juvenile hormone (JH), and the relatively high level of Vg and low level of JH usually lead to longer longevity. Telomerase activity and telomere length are influenced by the development and caste of honeybees. Queens inherit longer telomere length and maintain higher telomerase activity than workers. Overwintering worker bees live longer and show higher telomerase activity than the summer worker bees. Mitochondrial damage is a sign of senescence, while the mitochondrial function of the aged queen remains vigorous. Senescence is closely related to DNA methylation, and DNA methylation and histone modification play important roles in the regulation of plasticity in social insects. With the increase in population aging and the high prevalence of senescence-related diseases, “healthy aging” has triggered a series of concerns in life sciences and social sciences. Studies on honeybee senescence and longevity regulation will provide an important reference for the biology of senescence.

【Aim】The wheat blossom midge, Sitodiplosis mosellana, an important agricultural pest, survives under temperature extremes during summer and winter by diapause. This study aims to explore the relationship between heat shock protein 60 (Hsp60) gene expression and diapause development and temperature tolerance in the diapause process of S. mosellana.【Methods】 The full-length cDNA sequence of Hsp60 of S. mosellana (SmHsp60) was amplified via RACE and RT-PCR technologies, and analyzed via bioinformatics. qPCR was used to detect the expression levels of SmHsp60 in the S. mosellana larvae at different stages from pre-diapause to post-diapause development including pre-diapause, diapause, post-diapause quiescence and post-diapause development, as well as oversummering larvae under extremely high temperature stress ［exposed to water bathes at 34, 40, 45 and 50 ℃ for 1 h, and 35 ℃ for 0 (control), 15, 30, 60 and 120 min］ and overwintering larvae under extremely low temperature stress ［exposed to 0, -5, -10 and -15 ℃ for 1 h, and -5 ℃ for 0 (control), 15, 30, 60 and 120 min］. The recombinant SmHsp60 protein was obtained by prokaryotic expression and affinity column chromatography, and its ability to suppress the thermal aggregation of mitochondrial malate dehydrogenase (MDH) at 43 ℃ was examined by colorimetry and SDS-PAGE.【Results】 The full-length cDNA sequence of SmHsp60 (GenBank accession no: KR733065) of S. mosellana obtained is 2 270 bp in length, which contains an open reading frame (ORF) of 1 722 bp in length encoding a protein of 573 amino acids with the relative molecular weight of 60.7 kD. Amino acid sequence analysis indicated that SmHsp60 contains the classical signature sequences of mitochondrial Hsp60, and displayed the highest amino acid identity and the closest relationship to Hsp60 from Contarinia nasturtii of Cecidomyiidae. qPCR detection result showed that the expression level of SmHsp60 did not change significantly in the diapause stage, but began to increase gradually in the post-diapause quiescence stage with a peak in early-to-mid phase of post-diapause quiescence (i.e. December and next January) and was significantly higher than those in the other developmental stages. Compared to the untreated control, the expression of SmHsp60 in the oversummering larvae under 35 and 40 ℃for 1 h and 35 ℃ for 30-60 min and that in the overwintering larvae under -5 ℃ for 1 h was significantly induced, while the expression level of SmHsp60 did not change significantly above 45 ℃ or below -10 ℃. The highly purified recombinant SmHsp60 was able to effectively suppress the thermal aggregation of MDH, indicating its significant molecular chaperone function.【Conclusion】 SmHsp60 is involved in diapause regulation of S. mosellana and might play a role in diapause termination, as well as heat tolerance and cold tolerance during diapause.

 Apis cerana cerana is a critical and important pollinator in China. This bee species has a wide distribution in various habitats, and exhibits several advantages as pollinator, e.g., agility in flight, long nectar gathering period and strong adaptability. However, in recent years, A. c. cerana has been facing an unprecedented decline in population diversity. In order to protect the genetic resources of these specific populations, researchers studied the physiology and mechanism of genetic differentiation and environmental adaptation in A. c. cerana based on geometric morphology, molecular biology and genomics technologies. Meanwhile, the diverse populations of A. c. cerana in China provided rich materials for analyzing their adaptive evolution. In this article, we summarized the research progress from the four aspects: The correlation between population genetic differentiation and environmental changes, the morphological variation and environmental adaptation, the enviroment-adaptive physiological and behavioral changes, and the genetic mechanisms behind these phenotypic changes of A. c. cerana populations. Previous studies showed that changes in physical barriers and ecological environment, especially those related to altitude and latitude, were the main reasons for the differentiation of A. c. cerana populations. Among the climatic factors, temperature, oxygen, radiation and humidity had important effects on the morphological development and eco-physiological traits of A. c. cerana. The morphological changes were mainly explained by variation in body size and color. Changes in metabolic physiology and behaviors have been evolved as a crucial adaption strategy. Population genetics and genomics based on modern genomics and molecular biology techniques showed that genes and pathways related to social division of labor, learning and perceiving behavior, information perception, growth and development, thermal adaptation and metabolism are subject to natural selection. These findings provide molecular evidence for the ability of A. c. cerana to adapt to different habitats and the evolution of bee species. However, the specific molecular evolution mechanisms for the environmental adaption of bees await further investigation. Our review on the mechanisms of genetic differentiation and environmental adaption of A. c. cerana will deepen our understanding of the evolutionary history and genetic diversity of ancient bee species, and lay a foundation for further studies on the adaptive mechanisms of social insects to different environments and the development of effective conservation strategies.

 Protein and carbohydrate are two essential nutrients for insects. Protein is the source of amino acids for insect growth, while carbohydrate is the source of energy for activity. These two nutrients play important roles in insect growth, development and reproduction. In the nature, all insects experience heterogeneous nutritional landscapes, and the contents of proteins and carbohydrates in their food including plants or preys generally vary upon species, tissues or developmental stages. Thus, insects may have some strategies to find the food that contains the proper nutritional composition in their living environment so as to make their growth and development reach the optimal status. Geometric framework model has been demonstrated to be a powerful tool to investigate nutritional physiological regulation mechanisms in insects. This model has been extensively used in how insects coordinate different nutrients in food to achieve the balance of life processes, such as growth, development and reproduction. In herbivores, it is shown that the protein/carbohydrate ratio in food combining with environmental factors can affect the growth and development, as well as the immune response of insects. In predatory and social insects, it is shown that they can strictly regulate the intake of protein and carbohydrate nutrients to meet their needs. In model insects, it is shown that protein/carbohydrate ratio in food may have a balancing effect on lifespan and reproduction in insects. In this review, we introduced the working principle of geometric framework model and systematically summarized its application in insects, aiming to provide new ideas for the study of insect nutrition physiology and ecology.

【Aim】 Statistical analysis and study of insect grooming behaviors are important for pest control and human health. In view that the traditional method of manually recording grooming behaviors is time-consuming and error-prone, we proposed a computer vision and deep learning-based method for the detection and recognition of grooming behaviors of the Oriental fruit fly, Bactrocera dorsalis. 【Methods】 First, we processed the B. dorsalis video data to obtain frame images, and screened 3 000 images as the training dataset. We built the YOLO V7 target detection algorithm to detect B. dorsalis target in video data, and framed the target and cropped it by video processing algorithm. Finally, we migrated the pre-training weights to the training model by transfer learning method, and recognized seven grooming behaviors (foreleg grooming, head grooming, fore-midleg grooming, mid-hindleg grooming, hindleg grooming, wing grooming and stationary) of B. dorsalis using the temporal shift module (TSM) deep learning model based on non-local attention improvement. 【Results】 The accuracy and recall rate of the original video of the B. dorsalis dataset trained by YOLO V7 target detection algorithm were 99.2% and 99.1%, respectively. Applying this research algorithm to process the video dataset, and then recognizing and counting grooming behaviors through an improved TSM model based on the non-local attention module, we got the final average accuracy of over 97% with a standard deviation of less than 3%. Compared with the other four deep learning models (I3D, R2+1D, SlowFast and Timesformer), this research method had a ~9.76% improvement in accuracy, ensuring the accuracy of B. dorsalis grooming behavior detection and recognition. 【Conclusion】 The method proposed in this study greatly reduces the time of manual observation, and ensures the accuracy of grooming behavior recognition of B. dorsalis, providing new ideas and methods for researching insect behavior and contributing to the modern development of intelligent agriculture.

【Aim】 To analyze the differences in the midgut bacterial composition among different varieties of Bombyx mori with different vitalities and cocoon shell ratios, and their effects on the related traits such as vitality and cocoon shell ratio. 【Methods】 Based on the results of the long-term feeding survey on B. mori resource, the variety 932G with high vitality and the variety 2041J with high silk yield were selected as experimental materials, the midguts of the 5th instar larva and pupa were collected, and the 16S rDNA sequences of the midgut bacteria were sequenced and analyzed by the high-throughput sequencing platform to compare the differences in the composition and function of the midgut bacteria between different varieties and different developmental stages of B. mori. 【Results】 A total of 399 and 453 operational taxonomic units (OTUs) of the midgut bacteria were obtained from 932G and 2041J at the 5th instar larval stage, and 138 and 162 OTUs of the midgut bacteria were obtained from 932G and 2041J at the pupal stage, respectively. The dominant phyla of the midgut bacteria of B. mori at the 5th instar larval stage were Proteobacteria, Firmicutes and Actinobacteriota, and the dominant genus was Methylobacterium with the highest abundance, followed by Staphylococcus. However, there were significant differences in the relative abundance of some genera between the two varieties. The relative abundance of some genera including Devosia, Ralstonia, Nitrospira, Brachybacterium, Rothia, Lawsonella etc. in the midgut of the 5th instar larva of 932G was significantly higher than that in the midgut of the 5th instar larva of 2041J. The relative abundance of Pseudomonas, Methylobacterium, Acinetobscter, Cloacibacterium, Leuconostoc, Propionibacteriaceae, Psychrobacter, Sphingobium, Bacteroides etc. in the midgut of the 5th instar larva of 2041J was significantly higher than that in the midgut of the 5th instar larva of 932G. There were 77% and 78% functional genes in the midgut bacteria of the 5th instar larvae of 932G and 2041J enriched on the metabolic pathways of KEGG, respectively, followed by those of the function genes enriched on the environmental information processing and genetic information processing. The proportions of the midgut bacterial communities involved in nitrate reduction, nitrogen respiration, nitrate respiration, nitrite respiration and nitrogen fixation in the 5th instar larva of 932G were higher than those in 2041J. The proportions of the midgut bacterial communities involved in chemical heterotrophic, urea decomposition and methanol oxidation in the 5th instar larva of 2041J were higher than those in the 5th instar larva of 932G. The difference in the midgut bacterial composition between the 5th instar larva and pupa was significant. Erwinia of Proteobacteria in the midgut of the pupa was the dominant genus, and there was no significant difference in the relative abundance of Erwinia between the two varieties at the pupal stage. The relative abundance of functional genes involved in amino acid transport and metabolism, extracellular secretion and transport, carbohydrate transport and metabolism, and inorganic salt transport and metabolism of the midgut bacteria in the pupa was significantly higher than that in the 5th instar larva of 932G.【Conclusion】 There were significant differences in the midgut bacterial composition and predicted function between the varieties 932G with high vitality and 2041J with high silk yield of B. mori at the 5th instar larval stage. The composition and function of the midgut bacteria of B. mori at the pupal stage were significantly different from those of B. mori at the 5th instar larval stage, and there was no significant difference in the relative abundance of midgut bacteria between the two varieties at the pupal stage. These research results can provide a reference for further exploring the role of gut microorganisms in stress resistance, drug resistance, disease resistance, protein synthesis and transformation of B. mori and variety breeding.

【Aim】To explore the function of nuclear receptor ultraspiracle protein (USP) in the molting development of Sogatella furcifera nymph and its regulatory relationship with chitin synthesis and degradation. 【Methods】Based on the genome data of S. furcifera, the full-length cDNA sequence of SfUSP was amplified by RT-PCR. The expression levels of SfUSP in different developmental stages (1st-5th instar nymphs, 5th instar nymph prior to ecdysis, 5th instar nymph during ecdysis and female adult), tissues (head, integument, fat body, gut and leg) of the 5th instar nymph, female adult tissues (integument, wing, fat body, leg and ovary) and the day-1 5th instar nymph of S. furcifera after treatment with 100 ng/individual of 20E were detected by RT-qPCR. After the targeted silencing of SfUSP by microinjection of dsRNA into the day-1 5th instar nymph, the nymphal survival rate was calculated, the lethal phenotype of nymphs was observed and the expression levels of the key genes in chitin synthesis and degradation pathways were determined by RT-qPCR. 【Results】The full-length cDNA sequence of SfUSP (GenBank accession number: ON209396) of S. furcifera was obtained by cloning, with an open reading frame of 1 263 bp in length, encoding 420 amino acids. The predicted molecular weight of SfUSP is 47.27 kD with the theoretical isoelectric point of 7.18. Sequence analysis result showed that SfUSP contains five conserved domains of nuclear receptor family, and DNA-binding domain (DBD) and ligand-binding domain (LBD) are highly conserved. The developmental stage expression profiles showed that SfUSP was highly expressed in the 1st instar nymph, and the 5th instar nymphs prior to ecdysis and female adult. The tissue expression profiles showed that SfUSP was expressed highly in the head, integument, fat body and gut of the 5th instar nymphs, and in the wing, leg and integument of the female adult. In addition, at 12 h after microinjection of 20E (100 ng/individual), the expression level of SfUSP in the 5th instar nymph was significantly increased as compared with that in the control group. After targeted silencing of SfUSP expression, the nymphal survival rate of S. furcifera was significantly reduced compared with the control group (injected with dsGFP) and only 18.01% of that of the control group at 6 d after microinjection of dsRNA, with 51.46% individuals unable to molt successfully. In addition, after targeted silencing of SfUSP expression, the expression levels of the key genes SfCHS1, SfCHS1a, SfUAP and SfGFAT in chitin synthesis pathways and SfCht7, SfNAG1, SfNAG2, SfCDA1, SfCDA2 and SfCDA4 in chitin degradation pathways were significantly inhibited, but those of SfG6PI and SfCht10 were significantly increased as compared with those in the control group microinjected with dsGFP. 【Conclusion】SfUSP is a key gene in the growth and development of S. furcifera, which can affect the synthesis and degradation of chitin, and then regulates the ecdysis development of S. furcifera.

【Aim】The purpose of this study is to provide a theoretical reference for the further study on the function of the Niemann-Pick type C2 protein (NPC2) of Grapholita molesta GmolNPC2 in olfactory sensing.【Methods】Based on the antennal transcriptome data of G. molesta, the full-length cDNA sequence of GmolNPC2 was amplified by RT-PCR, and the phylogenetic analysis and 3D structure model prediction of GmoNPC2 were performed. The relative expression levels of GmolNPC2 in different developmental stages (egg, 1st-5th instar larvae, pupa, and female and male adults) and different tissues (antenna, head without antenna, thorax, abdomen, leg, and wing) of the 3-day-old male and female adults were detected by RT-qPCR. The inhibitory constant (K_i) values of the recombinant GmolNPC2 to 44 odorant ligands including six sex pheromones and 38 host plant volatile compounds were determined by fluorescence competitive binding assays to analyze the binding ability of GmolNPC2 to odorant ligands. By using molecular docking simulations, the binding energy of GmolNPC2 with different odorant ligands was calculated and the key amino acid residues of protein-ligand interactions were predicted.【Results】The full-length cDNA sequence of GmolNPC2 (GenBank accession no.: OQ054801) of G. molesta was obtained and the open reading frame (ORF) is 438 bp in length, encoding 145 amino acids. Multiple sequence alignment showed that GmolNPC2 has the typical structural characteristics of NPC2 of insects. Phylogenetic analysis showed that the reported NPC2s of lepidopteran insects were clustered into two branches, and the GmolNPC2 sequence was highly identic to the NPC2 sequences of Leguminivora glycinivorella, Pectinophora gossypiella, and Manduca sexta, which were clustered into one branch. RT-qPCR detection result showed that the expression levels of GmolNPC2 in the male adult and egg were significantly higher than those in other developmental stages. The expression level of GmolNPC2 was the highest in the wing of the 3-day-old male and female adults followed by that in the antenna, and the lowest in the thorax, abdomen, and leg. The binding spectrum of the recombinant GmolNPC2 was narrow with only 17 out of 44 tested odorant ligands, among which, the recombinant GmolNPC2 exhibited strong binding abilities to (Z)-8-dodecenyl acetate, benzyl alcohol, and cis-3-hexenyl acetate, with the K_i values of (4.117±0.046), (4.845±0.079) and (3.979±0.167) μmol/L, respectively. The molecular docking simulation result showed that the binding energy between GmolNPC2 and each odorant ligand was different, which was consistent with the results of the above fluorescence binding assays. Hydrophobic amino acid residues and hydrogen bonds play an important role in GmolNPC2 binding with different odorant ligands.【Conclusion】 GmolNPC2 has the conserved structure of the insect NPC2 family and is highly expressed in the egg and adult, and the wing and antenna of adult, speculating that GmolNPC2 participates in different physiological processes in G. molesta. The recombinant GmolNPC2 selectively binds sex pheromones and host plant volatile compounds, indicating the involvement of GmolNPC2 in the detection and transportation of volatile semiochemicals.

【Aim】 To explore the molecular mechanism of the natural enemy insect Arma chinensis in response to high or low temperature and UV-B stresses.【Methods】 The heat shock protein genes AcHsp83a and AcHsp83b of A. chinensis were cloned by RT-PCR, and their sequence characteristics were analyzed by bioinformatics methods. RT-qPCR was used to detect the expression levels of AcHsp83a and AcHsp83b in different developmental stages (egg, 1st-5th instar nymphs, female adult and male adult), different adult tissues (head, thorax, abdomen, wing, antenna, fat body, leg, Malpighian tubules, mouthparts, midgut, ovary and testis), and female and male adults at 0 (CK), 6 and 24 h after exposure to high temperature of 38 ℃, and low temperature of 4 ℃, and at 0 (CK), 6 and 12 h after UV-B stress.【Results】 Two Hsp90 genes were cloned from A. chinensis, and namely AcHsp83a (GenBank accession no.: OP791883) and AcHsp83b (GenBank accession no.: OP791884). Their open reading frames (ORFs) were 2 172 and 2 163 bp in length, encoding 723 and 720 amino acids with the relative molecular weight of 83.12 and 82.90 kD and the isoelectric point (pI) of 4.94 and 4.97, respectively, and the C-terminal sequences both contain the conserved motif EEVD, showing that they belong to the cytoplasmic Hsps. AcHsp83a and AcHsp83b are highly conserved. The expression level of AcHsp83a was the highest in eggs, whereas that of AcHsp83b was the highest in adults. The expression level of AcHsp83a was the highest in the testis of male adults, whereas that of AcHsp83b was the highest in the midgut of female adults. When the female adults were exposed to 38 ℃, 4 ℃ or UV-B, the expression levels of AcHsp83a and AcHsp83b increased firstly and then decreased with treatment time, reaching the peak at 6 h. For the male adults, the expression level of AcHsp83a increased firstly and then decreased with treatment time, and reached the peak at 6 h after exposure to 38 ℃ or UV-B. The expression level of AcHsp83a in male adults decreased firstly and then increased with treatment time, and reached the peak at 24 h after exposure to 4 ℃. Compared with the control group, 38 ℃, 4 ℃ or UV-B exposure significantly decreased the expression levels of AcHsp83b in male adults. 【Conclusion】 The differential expression of AcHsp83a and AcHsp83b in A. chinensis suggests that the two genes play important roles in the growth and development of A. chinensis and contribute to its tolerance to extreme temperatures and UV-B stress.

【Aim】Chelonus formosanus is an important parasitic natural enemy of a variety of lepidopteran pests. This study aims to identify and screen the suitable cold storage conditions of C. formosanus to extend its shelf life.【Methods】After the 7-day-old pupae of C. formosanus were stored at 5, 9 and 13 ℃ for 5, 10, 15, 20 and 25 d, respectively, the adult emergence rates, adult longevity, numbers of eggs laid by female adults in 24 h and adult parasitism rates, and adult emergence rates, proportions of females and adult longevity of progeny were observed and compared.【Results】When the 7day-old pupae of C. formosanus were stored at different low temperatures, the adult emergence rates and adult longevity decreased with the extension of storage time. At the same storage time except 5 d, the adult emergence rate showed an upward trend with the increase of temperature, and the adult emergence rate in the cold storage group at 13 ℃ was significantly higher than those in the cold storage groups at 5 and 9 ℃. Under the storage conditions of 9 and 13 ℃, with the extension of storage time, the number of eggs laid by female adults in 24 h showed a downward trend. After the 7-day-old pupae were stored at 9 ℃ for 10 and 15 d, the adult parasitism rates were significantly lower than that of the control group (stored at 24 ℃), and the adult parasitism rates between the other cold storage treatments and the control group showed no significant difference. When the 7-day-old pupae were stored at 5 ℃ for 5 d, the proportion of females of progeny was the lowest (only 35.27%). When the 7-day-old pupae of C. formosanus were stored at 13 ℃, the proportion of females of progeny showed no significant difference from that of the control. When the 7-day-old pupae of C. formosanus were stored at different low temperatures, the adult emergence rate and adult longevity of progeny did not differ significantly from those of the control group.【Conclusion】It was recommended that the 7-day-old pupae of C. formosanus should be stored at 13 ℃ for no more than 15 d.

【Aim】Based on the features that the P2C can be delivered into ovaries and the Gal4 protein can stably bind to the UAS sequence, to establish an efficient non-embryonic exogenous DNA delivery technical system in Anopheles sinensis.【Methods】The recombinant protein P2C-Gal4-DsRed was injected into the abdomen of female adults of A. sinensis at 20 h after sucking blood. The delivery efficiency of the recombinant protein P2C-Gal4-DsRed in the ovaries was analyzed by frozen section fluorescence observation and Western blot. The recombinant P2C-Gal4 DNA BINDING protein was prepared, transgenic plasmid and helper plasmid containing the 12×UAS repeat motif were constructed, and the in vitro binding between the recombinant protein P2C-Gal4 DNA BINDING and 12×UAS repeat motif was analyzed by electrophoretic mobility shift assay. The complexes P2C-Gal4 DNA BINDING recombinant protein+helper plasmid ITF36-12×UAS and P2C-Gal4 DNA BINDING recombinant protein+transgenic plasmid ITF2-12×UAS afm incubated in vitro were injected into the abdomen of female adults of A. sinensis at 20 h after sucking blood, and the DNA of their ovaries was extracted at 40 h after a blood meal. The delivery of exogenous DNA in vivo was analyzed by PCR amplification with specific primers and sequencing. 【Results】The ovaries of 100% female adults of A. sinensis injected with P2C-Gal4-DsRed showed obvious red fluorescence under the green filter, indicating that the P2C-Gal4-DsRed recombinant protein could be efficiently transferred into the ovaries of female adults of A. sinensis. The recombinant P2C-Gal4 DNA BINDING protein could stably bind to the 12×UAS repeat motif and the plasmid containing this repeat motif fragment. Exogenous DNA fragments were detected in the ovarian tissues of 91% and 93% of female adults of A. sinensis injected with P2C-Gal4 DNA BINDINGP2C-Gal4+ITF36-12×UAS and P2C-Gal4 DNA BINDING+ITF2-12×UAS afm, respectively. 【Conclusion】The exogenous DNA delivery technical system based on the P2C ovary-delivering peptide and the Gal4-12×UAS binding property was successfully established in A. sinensis. Through this technology platform, DNA molecules such as plasmids can be conveniently, rapidly and efficiently delivered into the ovaries of A. sinensis, laying a foundation for further simplifying genetic operations such as transgene, overexpression and gene knock-in.

【Aim】To clarify the effects of ultraviolet radiation to the parasitized host pupa on the growth and development of the parasitoid Trichopria drosophilae, so as to provide a reference for the mass breeding of T. drosophilae. 【Methods】Three ultraviolet irradiation lamps, UVA, UVB and UVC, were used to irradiate the parasitized Drosophila melanogaster pupae in a dark box. The irradiation duration was 3, 6 and 9 h, respectively. The pupal mortality rate, egg-adult duration, adult emergence rate, sex ratio (female to male ratio), and longevity of T. drosophilae were observed and calculated. 【Results】Compared to the control, UVA irradiation showed no significant effects on the adult emergence rate, pupal mortality rate and female to male ratio of T. drosophilae. After UVB irradiation for 3, 6 and 9 h, and UVC irradiation for 3 and 9 h, the adult emergence rates of T. drosophilae decreased significantly and the pupal mortality rates increased significantly compared to the control. The female to male ratios of T. drosophilae irradiated by UVB for 3, 6 and 9 h were greater than 2.00. After UVA irradiation for 3 and 6 h, and UVC irradiation for 3, 6 and 9 h, the egg-female adult duration of T. drosophilae was significantly lower than that of the control. After UVC irradiation for 3, 6 and 9 h, the egg-male adult duration of T. drosophilae was significantly lower than that of the control. The female adult longevity of T. drosophilae raised with the increase of irradiation duration of UVA, but showed no significant difference between the UVA irradiation groups and the control. The female adult longevity in UVB irradiation for 6 h was significantly higher than that in the control. The male adult longevity of T. drosophilae in ultraviolet irradiation treatments was higher than that of the control, and the male adult longevity in UVA irradiation for 3 h, UVB irradiation for 6 h and UVC irradiation for 9 h exhibited significant difference from that in the control. 【Conclusion】Ultraviolet irradiation treatment on the parasitized D. melanogaster pupae can significantly affect the egg-adult duration and adult longevity of T. drosophilae. The results of this study provide a reference for the multiplication of natural enemy resources for biological control of Drosophila pests.

【Aim】 To evaluate the parasitism potential of Cotesia ruficrus, an indigenous parasitic natural enemy, against the larvae of Spodoptera frugiperda, a major invasive agricultural pest. 【Methods】The parasitism preference of the mated 24 h-old female adults of C. ruficrus to the 1st-3rd instar larvae of S. frugiperda was performed by selection test. The developmental duration, numbers of cocoons, eclosion rates, sex ratios (proportions of females), adult longevity and adult size of the offspring of C. ruficrus were determined when its mated 24 h-old female adults parasitized the 1st, 2nd or 3rd instar larvae of S. frugiperda, respectively, by non-selection test. The oviposition times of the mated 24 h-old female adults of C. ruficrus on the 2nd instar larvae of S. frugiperda were determined by the direct observation method, and then the effects of different oviposition times on the developmental duration, number of cocoons, eclosion rate, sex ratio, adult longevity and adult size of the offspring of C. ruficrus were measured. The parasitic functional response of the mated 24 h-old female adults of C. ruficrus to the 2nd instar larvae of S. frugiperda was determined with small-leaf dish method. 【Results】 When the mated 24 h-old female adults of C. ruficrus parasitized the 1st-3rd instar larvae of S. frugiperda, the parasitism rates, egg-larval duration, pupal duration, numbers of cocoons per host, eclosion rates, and proportions of females of C. ruficrus were 34%-54%, 8.7-9.9 d, 3.9-4.1 d, 19.7-41.2 cocoons, 84.4%-92.0% and 31.5%-38.8%, respectively, and the female adult size of the offspring was larger than the males. The female adult longevity of the offspring of C. ruficrus was significantly longer than that of the males when the 1st or 3rd instar larvae of S. frugiperda were parasitized. The oviposition times of the mated 24 h-old female adults of C. ruficrus on the 2nd instar larvae of S. frugiperda had a significant effect on the biological characters of the offspring of C. ruficrus. With the increase of the oviposition times, the male adult longevity of the offspring of C. ruficrus was shortened, and the male adult size of the offspring became smaller. Compared with parasitization once, after the 2nd instar larvae of S. frugiperda were parasitized by the mated 24 h-old female adults of C. ruficrus for three times, the egg-larval duration of the offspring of C. ruficrus was significantly prolonged by 0.7 d, the pupal duration was shortened by 0.4 d, the number of cocoons per host significantly increased by 25 and the proportion of females significantly decreased by 58.8%. The parasitic functional response of the mated 24 h-old female adults of C. ruficrus to the 2nd instar larvae of S. frugiperda was Holling Ⅱ type, the daily maximum parasitic number was 17.5, the instantaneous attack rate was 0.043 and the average handling time was 1.368. 【Conclusion】 This study evaluated for the first time the biological control potential of C. ruficrus against S. frugiperda larvae, and indicated that the parasitoid was an effective native natural enemy of S. frugiperda, providing technical reserves and theoretical basis for further utilizing local natural enemies to control invasive pests.

【Aim】The aim of this study is to identify heat shock protein (Hsp) gene in Aphis gossypii(AgHsp90) and clarify the response of AgHsp90 to temperature, plant allelochemicals and insecticide stresses. 【Methods】RT-PCR and RACE were used to clone AgHsp90 of A. gossypii, and bioinformatics analysis was conducted. The expression levels of AgHsp90 in different developmental stages (1st-4th instar nymphs and adult) and in adults at 1 h after treatments with -5, 0, 5, 10, 15, 20, 30, 35, 38 and 42 ℃, and at 24 h after treatment with plant allelochemicals (20 mg/L tannic acid, 50 mg/L gossypol, 50 mg/L 2-tridecanone and 50 mg/L quercetin) and pesticide flupyradifurone stress［LC ₂₅(2.410 mg/L)］ were quantified by qRT-PCR. RNAi of AgHsp90 and heat shock factor (HSF) gene AgHSF of A. gossypii adult was performed for 24 h through feeding method to determine the mortality rate of A. gossypii adults at 24 and 48 h after treatments with 50 mg/L gossypol and LC ₄₀ (4.649 mg/L) flupyradifurone through feeding and leaf dipping methods, respectively, explore the effect of AgHsp90 on the susceptibility of A. gossypii to gossypol and flupyradifurone and preliminarily verify the mutual regulation between AgHsp90 and AgHSF. 【Results】One Hsp90 gene of A. gossypii designated AgHsp90 (GenBank accession no.: UOF38310) was obtained with a 2 181 bp ORF in length. The expression levels of AgHsp90 were relatively stable in different developmental stages, with the significant difference happened between the 3rd instar nymph and adult. Temperature stress experiment result revealed that AgHsp90 was obviously high temperature inducible, but low temperature downregulated the expression level of AgHsp90. The expression level of AgHsp90 in A. gossypii adult was not significantly induced by three plant allelochemicals (gossypol, tannic acid, and quercetin) and significantly induced by 2-tridecanone and LC ₂₅ flupyradifurone compared with the controls 0.5 mol/L sucrose and Triton X-100, respectively. RNAi of AgHsp90 could remarkably increase the mortality rate of A. gossypii adult resulted from gossypol and flupyradifurone compared with the control fed with ds GFP. AgHsp90 and its transcription factor AgHSF could mutually affect the expression levels using RNAi method. 【Conclusion】 The heat shock protein gene AgHsp90 of A. gossypii is high temperature and flupyradifurone inducible. AgHsp90 is mostly associated with the gossypol and flupyradifurone susceptibility of A. gossypii. The above results indicate that AgHsp90 may play crucial roles in response to high temperature and pesticide flupyradifurone stresses.