【Aim】 This study aims to further understand the symbiotic relationship between auchenorrhynchan insects of the order Hemiptera and endosymbionts by investigating the diversity and functions of obligate and facultative symbiotic bacteria in bacteriomes, fat bodies and other related tissues of adult Tettigetta isshikii at the ultrastructural and genomic levels. 【Methods】 Field-collected female and male adults of T. isshikii were investigated to clarify the distribution of symbiotic bacteria Karelsulcia, Hodgkinia and Wolbachia in the bacteriomes, fat bodies, ovaries, spermathecae, salivary glands, conical segment, filter chamber and gut of female adults, and testes of male adults through transmission electron microscopy and fluorescence in situ hybridization. Metagenomic sequencing, assembly and functions by genome annotation of symbiotic bacteria in the bacteriomes and fat bodies of female adults, and testes of male adults of T. isshikii were conducted. The phylogenetic relationships of Wolbachia in T. isshikii and other insects were determined using maximum-likelihood and Bayesian inference methods to determine the phylogenetic position of Wolbachia. 【Results】 The obligate symbiotic bacteria Karelsulcia and Hodgkinia are harbored in the bacteriomes of female adults of T. isshikii, and the facultative symbiotic bacterium Wolbachia, belonging to the supergroup F, was harbored not only in the cytoplasm and nuclei of the epithelial cells of testicular follicles but also in the nuclei of sperms of male adults and fat bodies of female adults. Genome annotation analysis revealed that genes of Karelsulcia and Hodgkinia were involved in the synthesis of essential amino acids and vitamins for the host cicada, while genes of Wolbachia were involved in riboflavin metabolism, heme pathway, and biosynthesis of purine and pyrimidine. The duplication of Wolbachia occured within the nuclei of sperms, which ultimately may lead to the rupture of nuclei. Phylogenetic relationship revealed that this Wolbachia belongs to the F supergroup and was closely related to the Wolbachia harbored in other arthropods and nematodes. 【Conclusion】 This study clarified the potential nutritional functions of symbionts Karelsulcia and Hodgkinia in the bacteriomes of T. isshikii adults, and elucidated a unique phenomenon that Wolbachia may have both beneficial and detrimental effects for the host insects. The results of this study contribute to a further understanding of the symbiotic relationship and complex co-evolution between Cicadidae and symbiotic bacteria.

As the most diverse group of animals on earth, insects are closely related to human production and activities, making entomological research both theoretically significant and practically valuable. In the past decade, the rapid development of novel methods and technologies has greatly promoted the research progress of entomological research. In this article, we provided a comprehensive overview of the applications of emerging methods and technologies in such fields as entomological morphological identification, molecular mechanism and pest management, focusing on the main contents of this special issue from seven aspects: Micro-computed tomography, RNA interference, gene editing, artificial intelligence-driven intelligent recognition, nanotechnology, regulation of insect-microorganism symbiotes, and olfactory behavior regulation. We also proposed the challenges faced by the large-scale application and sustainable development of these technologies, and prospected the future development trend.

 Aphids (superfamily Aphidoidea) are a group of globally distributed piercing-sucking insects, of which there are approximately 5 000 species. Some species such as cereal aphids, the cotton aphid Aphis gossypii, and the peach-potato aphid Myzus persicae threaten agricultural and forestry production. Typically, aphids absorb sap from plant phloem that induces a reduction in crop photosynthate accumulation, and are capable of transmitting more than half of known plant viruses. Furthermore, parthenogenetic reproduction and wing dimorphism facilitate rapid expansion and habitat transfer for aphid population. The strong ecological adaptability of aphids is inextricably linked to the population outbreak and infestation. It remains challenging for developing precise and effective control technologies for aphids due to strong resistance to pesticides caused by short generation time and parthenogenetic reproduction of aphids, and the non-target pests for Bt crops. In recent years, Chinese scientists have made a series of breakthroughs in the aphid genome divergence, the regulation of wingform and reproductive plasticity, salivary protein-mediated mechanisms of feeding and virus transmission, and insect-microbe symbiotic co-adaptation, leading to the development of pest control technologies like RNAi-based breeding for aphid resistance and ecological control by natural enemies. In this article, we summarized the latest advancements in this field in China, outlined the core scientific contributions of included papers, and provided a forward-looking perspective on future research directions such as the functional analysis of salivary glands at the single-cell level, the mechanisms of non-persistent virus transmission, epigenetic regulatory networks, and pest control technologies based on insect-microbe symbiosis, aiming to provide theoretical and practical foundations for scientific research and aphid control.

【 Aim 】 To investigate and analyze the changes in the structural composition, functional diversity and stability of terrestrial insect communities in different wetland types in Yinchuan, Northwest China. 【 Methods 】 Four wetland habitats including Yellow River wetland (HH), Mingcui Lake wetland (MCH), Luhuatai wetland (LHT) and Shuidonggou wetland (SDG) were selected based on the experimental design, and sampled from May to October, 2016. Insects were collected by chessboard sweeping and pitfall trapping approaches. Insect community structure diversity analysis, principal component analysis and cluster analysis were conducted based on the survey data. 【 Results 】 A total of 38 668 insects belonging to 370 species, 97 families and 13 orders were collected from the four wetland habitats in Yinchuan. Among them, Diptera, Homoptera, and Hymenoptera were the dominant groups in all the four habitats. Phytophagous insects accounted for the largest proportion in the family and species level of the insect communities among the four wetlands. The individual number showed a significantly negative correlation between the phytophagous and the neutral insects (Ph - Ne) in the four habitats (P<0.01). In the MCH habitat, the individual number showed a significantly positive correlation between the phytophagous and the predatory insects (Ph - Pr) (P<0.05), while a significantly negative correlation between the neutral and the predatory insects (Ne - Pr) (P<0.01). Additionally, in the LHT habitat, the individual number showed a significantly negative correlation between the neutral and the predatory insects (Ne - Pr) (P<0.05). Finally, the individual number in other combinations among the four functional groups did not show any significant correlation in all the four habitats. The predatory species group was the main component that affected the composition of the insect community based on principal component analysis (PCA). For the diversity analysis of the same functional group in the four habitats, there was a significant difference between the predatory (Pr) and the parasitic (Pa) functional groups based on the Simpson index (P<0 . 05), while there was no significant difference between the phytophagous (Ph) and the neutral (Ne) functional groups based on the Simpson index (P>0.05). Based on the Shannon - Wiener index, there was no significant difference among the neutral (Ne) functional groups in the four habitats (P>0.05), while there was a significant difference among the neutral (Ne) functional groups in the four habitats based on Pielou evenness index (P<0.05). Based on the Shannon - Wiener indices for the other three functional groups, there were significant differences among the four habitats (P<0.05), while they had no significant differences in the Pielou evenness index (P>0.05). The cluster analysis showed that the four types of wetlands were divided into two categories based on the characteristic index of insect communities, the first was permanent wetlands including HH and MCH, and the second was seasonal wetlands including LHT and SDG. Based on the stability index, the highest stability was found in the MCH habitat. The most stable periods for insect communities in different habitats were in May and September annually. 【 Conclusion 】 Diptera and Hymenoptera are the dominant groups in different wetland habitats in Yinchuan, and can be used as environmental indicators. The insect communities in the permanent lake wetland show the highest stability. The diversities of the insect communities in different habitats change with the seasons, and the most stable periods are in May and September annually. How the climatic factors and environmental factors drive the diversity to change and what factors affect the stability of insect communities in different wetlands remain to be studied.

 【Aim】To screen cellulose-degrading bacterial strains from the gut of Allomyrina dichotomus for constructing composite bacterial consortia and to investigate their degradation capacity for spent mushroom substrate (SMS), thereby providing theoretical and practical foundations for SMS waste management.【Methods】Composite bacterial consortia were constructed based on non-antagonistic relationships among six cellulose-degrading bacteria with high enzyme activity (Bacillus velezensis M24, Bacillus subtilis H12, H11, H4 and M33, and Bacillus siamensis M32) isolated and purified from the larval gut of A. dichotomus. The activities of four cellulases (filter paper enzyme, endoglucanase, exoglucanase and β-glucosidase) were determined, the optimal composite bacterial consortia was selected according to its enzymatic activity profile, and the culture time, inoculation amount and incubation temperature for the selected composite bacterial consortia were optimized. The structural changes in the spent mushroom substrate before and after degradation were observed through scanning electron microscope by differential weight method.【Results】The composite bacterial consortia M24∶H11 was constructed based on the enzymatic activities of filter paper enzyme, endoglucanase, exoglucanase and β-glucosidase (18.08, 69.37, 19.09 and 17.95 U/mL, respectively). The optimal culture time, inoculation amount and culture temperature of M24∶H11 were 2 d, 1% and 40 ℃, respectively. Following optimization, the activities of the four cellulases increased significantly by 1.98-2.16-fold. At 25 ℃ within 30 d, M24∶H11 showed a significantly higher SMS degradation rate (up to 38.04%) than individual strains, with the degradation rate increasing over time. The degradation by M24∶H11 effectively disrupted the SMS surface structure, increasing its contact area.【Conclusion】The larval gut-derived composite bacterial consortia M24∶H11 of A. dichotomus was constructed and optimized for enzyme production, with high efficiency in SMS degradation. This study offers novel technical insights and theoretical support for the efficient control of the edible fungi waste.

【Aim】This study aims to explore the effects of exogenous juvenile hormone (JH) on the female ovarian development and transcription levels of the reproduction-key genes of Spodoptera frugiperda.【Methods】Polyclonal antibody was prepared after isolation and purification of vitelline protein of female S. frugiperda. The vitelline protein contents in the 7-8-day-old female pupae and 1-10-day-old female adults of S. frugiperda were determined using indirect enzyme-linked immunosorbent assay (ELISA). The 5-day-old female pupae were treated with 25 μg/individual precocene, and the newly emerged female adults were supplemented with 100 μg/individual exogenous JH analogue methoprene. Subsequently, the preoviposition period, oviposition period, number of eggs laid per female and hatching rate were calculated. The 3-day-old female adults were dissected to observe the ovarian development, measure the ovarian length, and take photographs. Finally, the expression levels of genes of vitellogenin (Vg) and vitellogenin receptor (VgR) in the 3-day-old female adults of each treatment were quantified using qPCR.【Results】The vitellin content of S. frugiperda increased first and then decreased as female adult emerged, reaching its peak in the fat bodies at 1-day-old and ovaries at 4-day-old. Precocene treatment resulted in a downregulation of the endogenous JH in S. frugiperda, leading to obvious impediment of ovarian development compared to the normally reared female adults as the blank control group. Additionally, there was a significant reduction in the amount of ovarian eggs. However, exogenous supplementation of methoprene after the precocene treatment effectively restored normal ovarian development. The average ovarian length in the precocene treatment group was 39.89 mm, which was significantly shorter than that in the blank control group of 49.79 mm. The average ovarian length in the methoprene treatment group was 46.67 mm, and significantly longer than that in the precocene treatment group, but had no significant difference from that in the blank control group. The average number of eggs laid per female in precocene treatment group significantly decreased to 576.33 grains, as compared to that in the blank control group (1 128.37 grains), significantly decreased by 48.91%. The average number of eggs laid per female in the methoprene treatment group was 806.93 grains, which was significantly higher than that in the precocene treatment group. The expression levels of SfVg and SfVgR in female adults treated with precocene were significantly downregulated as compared to those in the blank control group, while methoprene significantly promoted the expression levels of SfVg and SfVgR.【Conclusion】The suppression of endogenous JH through precocene treatment significantly impeded female fecundity, hindered normal ovarian development, and reduced the transcription levels of SfVg and SfVgR in female adults of S. frugiperda. Conversely, exogenous JH supplementation effectively restored the female fecundity. This study further validates the crucial regulatory role of JH in the reproductive process of S. frugiperda and provides a theoretical foundation for future research on the regulatory mechanism of JH of female reproduction.

【Aim】 To elucidate the effects of Cnidium monnieri on ladybird conservation and aphid control during the whole growth period of wheat and maize. 【Methods】 The occurrence amounts of ladybirds and aphids in wheat and maize fields with C. monnieri planted and the control with pure crops planted were systematically investigated and counted by visual observation throughout the year, and the spatio-temporal correspondence between ladybirds and aphids was clarified. 【Results】 Planting C. monnieri significantly increased the occurrence amounts of natural enemy ladybirds in wheat and maize fields, which in turn significantly reduced the occurrence amount of aphids. In 2020 and 2022, the peak numbers of ladybirds in wheat fields with C. monnieri planted were 25.33 and 9.00 individuals/m², respectively, which were significantly higher than those in the control wheat fields (11.73 and 5.33 individuals/m², respectively). Concurrently, the peak total numbers of aphids in wheat fields with C. monnieri planted were 786.00 and 817.33 individuals/100 plants, respectively, which were significantly lower than those in the control wheat fields (932.67 and 1 133.33 individuals/100 plants, respectively). During the same period, the peak numbers of ladybirds in maize fields with C. monnieri planted were 77.53 and 109.33 individuals/100 plants, respectively, which were significantly higher than those in the control maize fields (50.67 and 77.33 individuals/100 plants, respectively). In 2020, no significant difference was shown in the peak number of Rhopalosiphum maidis in maize fields between treatment and the control. However, on one week after the peak period of R. maidis, the individual number of R. maidis per 100 plants in maize fields with C. monnieri planted was 2 209.33, significantly lower than that in the control maize fields (5 926.67). In 2022, the individual number of R. maidis per 100 plants in maize fields with C. monnieri planted was 13 533.30, significantly lower than that in the control maize fields (30 600.00). 【Conclusion】 Planting C. monnieri in wheat-maize rotation cropping system can conserve natural enemy ladybirds throughout the year, effectively suppressing the occurrence of wheat aphids and R. maidis, thereby exerting a good ecological pest control effect.

【Aim】 The camellia weevil,  Curculio chinensis Chevrolat, is an important pest attacking fruits of the oil tea  Camellia, an endemic genus to China, and causes tremendous fruit drop of its host plants. To reveal the oviposition strategy of  C. chinensis, we explored the relationships between oviposition activity of C.chinensis  and the traits of its host fruit. 【Methods】 During the most active oviposition season, 960 fruits of  C. meiocarpa  were collected randomly from an oil tea ( Camellia meiocarpa) farm. The number of punctures and clutch size of C. chinensis, as well as the weight, length and diameter of each fruit were measured, and the difference of fruit size among oviposition-punctured fruits, feeding-punctured fruits and non-damaged fruits was analyzed through one-way ANOVA (LSD), and the effect of fruit traits on feeding and oviposition activity was analyzed through linear regression model. A choice test of the pest on fruits size was carried out, and the difference of fruit size between selected and non-selected fruits was analyzed by paired-samples t test. 【Results】 Oviposition-punctured fruits of C. meiocarpa were significantly larger than feeding-punctured fruits, while the latters were significantly larger than non-damaged fruits in terms of weight, length, diameter, and volume ( P＜0.01). The number of punctures, clutch size and weevil parasitism rate were positively correlated with fruit size ( P＜0.01), suggesting that parental weevils prefer larger fruits to feed and oviposite. The female adults of C. chinensis showed obvious preference to larger fruits when the difference of fruit size between the two fruits tested was significant, and heavily damaged fruits were significantly larger than lightly damaged fruits in terms of length and diameter after infection by female adults of C. chinensis for 12 h. Independent of host fruit traits, C. chinensis laid one egg in each puncture hole. 【Conclusion】 C. chinensis adults prefer larger fruits to feed, which supports the optimal foraging theory. C. chinensis adults also prefer larger fruits to oviposite. The small clutch size would reduce intraspecific competition C. chinensis between offsprings and increase the probability of larval development, and thus they would be more likely to successfully exit from host fruits. We infer that the single egg laying behavior in C. chinensis is a riskspreading strategy, an adaptation toward limited food resource.

 Aphids, a group of widely distributed piercing-sucking insects, rely on the symbiotic relationship with the primary endosymbiont Buchnera to acquire essential nutrients for survival and reproduction. During the long-term coevolution, aphids have developed specialized bacteriocytes to mediate nutrient exchange with Buchnera while avoiding immune activation. This intracellular symbiosis is maintained through vertical transmission dependent on endocytosis and exocytosis mechanisms, ensuring persistent infection of Buchnera within aphid populations. However, the stable nutrient supply in endosymbiotic environment leads to extensive genome degeneration in Buchnera. On the one hand, the systematic loss of genes related to redundant nutrient metabolism and environmental stress response has resulted in the loss of over 90% of the genes of Buchnera genomes, leading to drastic genome reduction. On the other hand, the physical barrier formed by bacteriocytes prevents Buchnera from acquiring new genes from external bacteria, at the same time, the absence of key genes involved in DNA repair leads to the loss of mutation repair ability. These factors collectively result in extreme AT content and continuous functional gene loss in the genome of Buchnera. The genomic degeneration of Buchnera compromises its metabolic functions, manifesting as reduced essential amino acid synthesis, loss of key genes involved in inorganic salt metabolism, and dysregulation of heat shock protein expression. These deficiencies accelerate aphid speciation and reduce their adaptability under heat stress. To compensate for these obligate symbiotic constraints, aphids employ strategies such as acquiring secondary symbionts or replacing primary symbionts. Some lineages have even evolved dual primary symbionts, alleviating adverse effect of genomic degradation through functional complementation. In this review, we summarized the evolutionary paradox in aphid- Buchnera symbiosis. Although the degeneration of Buchnera genome improved the efficiency of nutrient supply, it restricted the adaptation of aphid hosts to the environmental changes. We further proposed novel compensatory strategies developed by aphids to overcome obligate symbiotic constraints, offering new perspectives for understanding relationship between insects and endosymbionts, and laying theoretical foundations for aphid control strategies targeting symbionts.

【Aim】 Aromia bungii Faldermann is a main wood borer of peach， apricot， plum and cherry in China. Dastarcus helophoroides (Fairmaire) is an important insect natural enemy of large-body longhorned beetles and has six different host-originated populations by now. This study aims to screen a suitable D. helophoroides population to control A. bungii. 【Methods】  The behavioral responses of adults of different populations of D. helophoroides to larval frass of A. bungii were assayed with Y-tube olfactometer. The control effects of different populations of D. helophoroides on A. bungii populations in the peach logs were also tested by releasing parasitoid adults under the semi-field conditions. 【Results】  D. helophoroides populations originated from Batocera horsfieldi and Monochamus alternatus were significantly attracted to larval frass of A. bungii， but other populations of D. helophoroides were not attracted to larval frass of A. bungii. Consecutive observation of the control effects in two years showed that D. helophoroides population originated from Anoplophora glabripennis caused the highest mortality of A. bungii (52.86%±5.97%). D. helophoroides populations originated from M. alternatus， B. horsfieldi， Massicus raddei， Apriona swainsoni caused the mortality rates of A. bungii of 35.14%±5.55%， 32.88%±5.50%， 26.09%±5.29% and 10.94%±3.90%， respectively. D. helophoroides population originated from Anoplophora chinensis did not cause higher mortality of A. bungii individuals than the control. 【Conclusion】 Based on the results it is suggested that three D. helophoroides populations originated from M. alternatus， B. horsfieldi and A. glabripennis could be chosen as the biological control agents of A. bungii.

【Aim】 As one of the most important insects endohormones, ecdysone plays an important role in regulating the development and reproduction of insects. Five Halloween genes are involved in ecdysteroid biosynthesis and encode cytochrome P450 enzymes spook/CYP307A1, Phantom/CYP306A1, disembodied/CYP302A1, shadow/CYP315A1 and shade/CYP314A1, respectively. The brown planthopper, Nilaparvata lugens, is one of the most destructive pests of rice throughout Southeastern and Eastern Asia. For N. lugens, ecdysteroid regulated genes of RNAi technology management has gradually become a research hotspot. The objective of this study is to investigate the function of Halloween genes in N. lugens so as to provide the theoretical basis for the management of N. lugens and development of new pesticides. 【Methods】 Based on the genome and transcriptome database of N. lugens, five ecdysteroidogenesis-related Halloween genes in N. lugens were cloned using RT-PCR, and the deduced protein structure was predicted using different bioinformatics software, and the phylogenetic tree was constructed using the neighbor-joining method of MEGA 5.0. The expression profiles of these genes in different tissues of nymph and at different developmental stages of N. lugens were detected by quantitative real-time PCR. RNAi experiment was carried out to examine the effects of knockdown of Halloween genes on the development and reproduction of N. lugens. 【Results】 Five Halloween genes involved in ecdysteroidogenesis, i.e., NlCyp307a1, NlCyp306a1, NlCyp302a1, NlCyp315a1, and NlCyp314a1, were cloned and identified in N. lugens. Phylogenetic analysis revealed that the five Halloween genes belong to two superfamilies 2-Clan and Mito-Clan, respectively, and clustered with their homologous genes in other insects, suggesting that Halloween genes and edysteroidogenesis pathways are very highly conserved during insect evolution. NlCYP314A1 contains five conserved P450s motifs and two transmembrane domains, being a typical mitochondria cytochrome P450s. The results of qRT-PCR showed that five Halloween genes had higher mRNA abundance at 24 h and 60 h after molting in the 5th instar nymph stage. NlCyp314a1 was continually expressed during the whole developmental stage, and showed the highest expression level in adults. Among the examined tissues, thorax had the higher transcription level of NlCyp314a1 than head and abdomen, and fat body had the highest transcription level of NlCyp314a1, followed by leg, integument, wing bud, and midgut. Four days after injection of ds NlCyp314a1, the expression levels of NlCyp314a1 and NlFTZ-F1 in the treated individuals were extremely significantly decreased by 84.6% and 64.1%, respectively, compared with the control. NlCyp314a1 knockdown resulted in nymphs failed to molt on time, exhibited apparent phenotypic defects, and >95% mortality of the nymphs at day 7 after injection. NlCyp314a1 knockdown also resulted in the developmental abnormality of adult ovary. 【Conclusion】 Halloween genes of N. lugens involving in ecdysteroidogenesis are evolutionarily conserved. Silencing of selected Halloween gene expression causes phenotypic defects in molting and reproduction. These results suggest that Halloween genes encode functional proteins that are involved in molting and reproduction of N. lugens. Halloween genes might be used in altering genetically the progress of molting and reproduction of N. lugens. This study provides a theoretical basis for potential application of Halloween genes in the management of N. lugens.

【Aim】 This study aims to explore the physiological responses of silicon-treated rice plants to feeding stress by the white-backed planthopper, Sogatella furcifera, so as to provide a theoretical foundation for the rational use of silicon fertilizer in controlling S. furcifera. 【Methods】 The plants of the susceptible rice variety TN1 were treated with two silicon application levels ［grown in nutrient solution added with sodium silicate (Na₂SiO₃·9H₂O) at the concentration of 112 mg/L(Si+treatment group), and without addition of silicon (control group)］, then exposed to the feeding of the 3rd instar nymphs of S. furcifera. The contents of superoxide anion (O^-·₂), hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), the activities of antioxidant enzymes ［superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT)］ and defense enzymes ［phenylanlanine ammonialyase (PAL), polyphenol oxidase (PPO) and lipoxygenase (LOX)］, and lignin content in rice leaf sheaths were measured at 0, 12, 24, 48, 72 and 96 h after feeding on the rice plants in the Si+ treatment group or the control group. 【Results】 Compared to the control group, the Si+ treatment group exhibited significant reductions in O^-·₂ content by 7.8%-17.9% in rice leaf sheaths during 12-72 h after S. furcifera feeding, in H2O2 content by 15.5%-43.1% in rice leaf sheaths during 12-96 h (except at 24 h) after S. furcifera feeding, and in MDA content by 15.1%-35.3% in rice leaf sheaths during 24-96 h after S. furcifera feeding. During 12-96 h (except at 72 h) after S. furcifera feeding, the CAT and SOD activities in rice leaf sheaths in the Si+ treatment group were significantly increased by 25.8%-44.8% and 21.4%-47.6%, respectively, as compared to those in the control group. During 12-72 h (except at 24 h) after S. furcifera feeding, the POD activities in rice leaf sheaths in the Si+ treatment group significantly increased by 19.1%-54.5%, as compared to those in the control group. During 12-72 h after S. furcifera feeding, the PAL and PPO activities in rice leaf sheaths in the Si+ treatment group were significantly elevated by 17.6%-70.8% and 16.7%-38.3%, respectively, as compared to those in the control group. During 12-96 h after S. furcifera feeding, the LOX activities in rice leaf sheaths in the Si+ treatment group significantly increased by 9.9%-105.4%, as compared to those in the control group. During 12-96 h (except at 48 h) after S. furcifera feeding, the lignin contents in rice leaf sheaths in the Si+ treatment group significantly raised by 12.5%-59.3%, as compared to those in the control group. 【Conclusion】 Silicon application enhances rice resistance to S. furcifera by reducing reactive oxygen species and MDA contents, as well as by increasing the activities of antioxidant enzymes and defense enzymes, and the lignin content in rice leaf sheaths infested by S. furcifera.

【Aim】 This study aims to clarify the distribution pattern and feeding behaviors of Semiaphis heraclei on the adaxial and abaxial sides of Lonicera japonica leaves, and explore the control efficacy of spraying pesticides on the adaxial and abaxial sides of L. japonica leaves against S. heraclei, so as to provide a scientific basis for optimizing the control strategies of S. heraclei. 【Methods】 From April to May 2023, the occurrence amounts of S. heraclei on the adaxial and abaxial sides of L. japonica leaves at different leaf positions in the experimental field in Beijing were investigated every 5 d, the electrical penetration graph (EPG) technique was used to record the feeding behaviors of the 1-3-day-old adults of S. heraclei on the adaxial and abaxial sides of mature L. japonica leaves aged 30 d, and 0.027 mg/cm² imidacloprid and 0.020 mg/cm² pyrethrin were sprayed on the adaxial and abaxial sides of mature L. japonica leaves aged 30 d, respectively, and the mortality rates of the 1-3-day-old adults of S. heraclei on leaves were determined. 【Results】 S. heraclei adults were distributed on the adaxial side of L. japonica leaves at the first leaf position early and later shifted to the abaxial side. The abaxial sides of the middle part of almost all leaves consistently had significantly higher aphid numbers than the adaxial leaf sides throughout. A small number of aphids were found on individual leaves of basal leaf position, primarily on the abaxial leaf side. When S. heraclei adults fed on the abaxial leaf side of L. japonica, the probability of occurrence of aphid’s stylet salivation waveform in the phloem (E1 waveform) was significantly higher than that on the adaxial leaf side, being 2.00-fold as high as that on the adaxial leaf side, the total duration of E1 waveform was significantly longer than that on the adaxial leaf side, being 3.24-fold as long as that on the adaxial leaf side, and the probability of occurrence of phloem sap ingestion waveform (E2 waveform) was 2.25-fold as high as that on the adaxial leaf side. When S. heraclei adults fed on the xylem on the abaxial leaf side of L. japonica, the probability of occurrence of xylem sap ingestion waveform (G waveform) was significantly higher than that on the adaxial leaf side, being 1.29-fold as high as that on the adaxial leaf side, and the total duration of G waveform was significantly longer than that on the adaxial leaf side, being 2.00-fold as long as that on the adaxial leaf side, while the total duration of E2 waveform of S. heraclei adults fed on the adaxial and abaxial leaf sides exhibited no significant difference. The control efficacy of spraying 0.027 mg/cm² imidacloprid and 0.020 mg/cm² pyrethrin on the abaxial leaf side against S. heraclei adults was significantly higher than that on the adaxial leaf side, causing the corrected mortality rates of S. heraclei on the abaxial leaf side to be 2.00 and 1.79-fold as high as those on the adaxial leaf side, respectively. 【Conclusion】 S. heraclei adults are mainly distributed and cause damage on the abaxial side of L. japonica leaves, where it is more favorable for them to absorb water, and the control efficacy of spraying pesticides on the abaxial side of L. japonica leaves against S. heraclei adults is higher than that on the adaxial side.

【Aim】 Epacromius coerulipes (Ivanov) is one of the most widely distributed grassland locusts. However, there is a lack of genomic resources. In order to obtain genetic data of E. coerulipes, this study conducted the transcriptome sequencing and analysis. 【Methods】 De novo assembly of the transcriptome was conducted using Illumina paired-end sequencing technology. 【Results】 In total, 63 033 unigenes with a mean length of 772 bp and an N50 length of 1 589 bp were obtained. Of these unigenes, 25 132(39.87%) unigenes were matched with the known proteins in the National Center for Biotechnology Information (NCBI) database, as determined by BLAST search, with 24 841, 16 490, 11 558 and 8 013 unigenes assigned to Nr database, Swiss-Prot, Gene Ontology (GO) and Clusters of Orthologous Groups (COG), respectively. In KEGG database, a total of 7 218 unigenes were assigned to 218 known pathways. Among these, 189 unigenes were involved in metabolic pathways of xenobiotics or drugs. In-depth analysis of the data showed that 213 unigenes were identified as potentially involved in the detoxification of xenobiotics, and 29 unigenes were identified as encoding insecticide target proteins. In addition, 5 696 simple sequence repeats (SSRs) were detected. 【Conclusion】 This study lays the foundation for further research on gene function analysis and molecular resistance mechanisms to insecticides in E. coerulipes.

【Aim】 As the main factors, the amplitude of temperature fluctuation and the change of population density affect life history traits and population dynamics of insects, and have received widespread attention. Previous studies have shown that there is a complex and significant interaction between temperature and population density, but most studies focus on constant temperature, which cannot reflect the effects of actual temperature changes in nature on insect populations. Therefore, we focused on Rhopalosiphum padi as one of major wheat pests worldwide in this study and explored the effects of temperature amplitudes and population density on the life history traits and population parameters of R. padi through the indoor simulation of field temperature fluctuations and population density. 【Methods】R. padi nymphs newly born within 4 h were treated under the conditions of different temperature amplitudes［(22±0), (22±6) and (22±12) ℃］ and population densities (1, 2, 4 and 8 individuals/tube), the development, survival, longevity and fecundity were observed daily, and the population parameters such as intrinsic rate of increase, net reproductive rate and generation time were calculated. 【Results】 At the low population density (1 individual/tube), compared with the constant temperature ［(22±0) ℃］, high temperature amplitude (22±12) ℃ prolonged the nymphal duration by 1.24 d, reduced the adult fecundity (total number of offspring produced per adult) by 19.1 individuals/adult, and decreased the intrinsic rate of increase and net reproductive rate by 0.10 d-1and 18.7, respectively, and prolonged the generation time by 1.86 d. Under the constant temperature ［(22±0) ℃］, compared with the low population density (1 individual/tube), the high population density (8 individuals/tube) reduced the adult fecundity by 24.2 individuals/adult, and the intrinsic rate of increase, net reproductive rate and generation time by 35.3 d-1, 0.05 and 0.22 d, respectively. As population density increased, the high temperature amplitude ［(22±12) ℃］ exerted a stronger inhibition effect on the nymphal development, intensively shortened the adult longevity, and intensively reduced the intrinsic rate of increase and net reproductive rate. However, high population density not only reversed some of the adverse effects of high temperature amplitude on the fecundity but also enhanced the nymphal survial. 【Conclusion】 The results of this study show the complex effects of temperature amplitude and population density on the life history traits and population dynamics of R. padi, suggesting that previous insect survival models based on constant temperature cannot accurately describe the real status of insects under temperature variations in nature. The results will improve the accuracy of predicting and forecasting the population dynamics of field pests and formulating control strategies under climate change.

【Aim】 To confirm the effectiveness of electroporation-mediated functional analysis system in the silkworm, Bombyx mori. 【Methods】 siRNAs were synthesized for the target gene Wnt1 (Wingless), which is known to be involved in larval melanin coloration in B. mori. The day-3 4th instar larvae of B. mori were injected with Wnt1 siRNAs and subjected to electroporation as the treatment group (ERFA-RNAi) and those injected with Wnt1 siRNAs but without subjected to electroporation were used as the negative control group, the epidermis of the corresponding speckled area of the 5th instar larvae was dissected, and the relative expression level of Wnt1 in the epidermis was detected with real-time quantitative RT-PCR (qRT-PCR) to verify the effect of electroporationmediated RNAi. The transposon vector pPIG-A3GR with the enhanced green fluorescent protein reporter gene (EGFP) and the red florescence protein (RFP) reporter gene (DsRed2) expression cassettes, was introduced into the 2nd instar larvae of B. mori by electroporation. After 72 h of normal rearing, the expression of EGFP and DsRed2 in the larvae was observed under a fluorescent stereo microscope, to verify the somatic transgenesis of the silkworm. 【Results】 After the introduction of Wnt1 siRNAs into the day-3 4th instar larvae of B. mori, the formation of a speckle pattern of the 5th instar larvae was prevented on the larval body surface, and the qRT-PCR analysis showed that the expression level of Wnt1 in the epidermis of the 5th instar larvae was significantly decreased. The positive rate of somatic transgenic silkworm was 56.60%, and two fluorescent reporter genes EGFP and DsRed2 were continuously expressed in larval, pupal and adult stages. 【Conclusion】 Electroporation is an efficient technology for exploration of gene function in vivo, by efficiently introducing exogenous RNA or DNA into silkworm.

 【Aim】 To clarify the spatiotemporal expression pattern of the juvenile hormone receptor methoprene-tolerant gene AsMet in Anopheles sinensis and explore its influence on the reproductive regulation and development of An. sinensis.【Methods】 Based on the transcriptome data of An. sinensis, the full-length cDNA sequence of AsMet was cloned by RACE and its molecular characteristics were analyzed. qPCR was used to analyze the expression levels of AsMet in different developmental stages (pupa and female adult) and different tissues ［head, throax, anterior part of abdomen (the first 3 segments of abdomen), posterior part of abdomen (the remaining part of abdomen), midgut, Malpighian tubules, fat body, ovary and integument］ of the 3-day-old female adults. dsAsMet was microinjected into the last instar female pupa for RNAi, and the expression levels of AsMet, AsKr-h1 and AsVg, the development of ovaries of female adults, emergence rate, number of eggs laid and egg hatching rate were observed and detected.【Results】 The full-length cDNA sequence of AsMet of An. sinensis (GenBank accession no.: OR783325) was 6 841 bp with the open reading frame (ORF) of 3 159 bp in length, encoding 1 052 amino acids with the predicted molecular weight of 114.46 kD and the isoelectric point of 6.63. AsMet had four conserved domains, including one helix-loop-helix domain, two PAS-binding domains, and one C-terminal conserved motif. AsMet clustered with Mets of An. gambiae, Aedes aegypti and Culex pipiens. AsMet was significantly highly expressed at 30 h after pupation and at most stages of adults, significantly highly expressed in the head and thorax of female adults, and lowly expressed in the midgut, Malpighian tubules and ovary. The expression levels of AsMet were reduced by 70.05%, 41.05% and 68.64%, respectively, at 24, 48 and 72 h after dsAsMet microinjection into the last instar female pupa as compared with those in the control group microinjected with dsEGFP. The emergence rate in microinjection group with dsAsMet was lower than that in microinjection group with dsEGFP, and after mating and blood-feeding the ovaries were agenesia, and the number of eggs laid decreased by 67.58% as compared with that in microinjection group with dsEGFP, and the egg hatching rate in microinjection group with dsAsMet was reduced by 93.10% compared with that in microinjection group with dsEGFP.【Conclusion】The decreased expression of AsMet can reduce the normal development of ovary, and decrease the number of eggs laid and egg hatching rate significantly. The results lay a foundation for further research on the mechanism of JH regulation of reproductive development of An. sinensis, and provide a theoretical basis for understanding the signaling pathway of juvenile hormone and the molecular mechanism of insect reproductive regulation.

 Tomato is one of the most important horticultural crops, and China is the largest producer of tomato in the world. In recent years, the tomato industry is facing increasingly severe pest threats including the traditional important pests (Bemisi tabaci, Frankliniella occidentalis and Helicoverpa armigera) and the newly emerged invasive pest Tuta absoluta. Elucidating the defensive mechanism of tomato especially wild tomato germplasm resource, which has significantly higher resistance to pests, can provide important genetic resources for breeding process of insect-resistant tomato varieties. Meanwhile, the key insect-resistant metabolites of tomato can also offer valuable insights into the development of new safer and more eco-friendly botanical pesticides. In this article, we summarized the interactions between tomato pests and host plants like tomato across multiple levels of insect resistance mechanisms in plants. Key topics include: (1) the recognition of saliva proteins from piercing-sucking and chewing insects by tomatoes and its impact on anti-insect immunity; (2) the signal transduction networks of insect resistance and the regulatory mechanisms of core defense-related transcription factors in tomato; (3) structural and metabolic bases of insect resistance in plants, such as trichomes, acylsugars, phenolamides, steroidal alkaloids, and volatile compounds, which respond to pest attacks and confer insect resistance through molecular and ecological pathways. Future research should leverage emerging technologies like single-cell transcriptomics and spatial transcriptomics, combined with gene editing and genetic manipulation tools, to further clarify the signaling pathways of insect resistance and the synthesis and regulation of defense compounds in tomato. These efforts will deepen our understanding of plant-insect interactions and lay a theoretical foundation for breeding high-yield, insect-resistant tomato varieties.

【Aim】 Picromerus lewisi is a significant predatory natural enemy insect distributed in multiple countries of Asia, such as China, Korea and Japan, primarily used for controlling lepidopteran pests. Venom plays a crucial role in causing rapid paralysis and death of preys during hunting. The aim of this study is to understand the transcriptomic characteristics of the venom glands of P. lewisi, explore the diversity of toxins in P. lewisi, and establish a foundation for further research on the composition and function of the venom in P. lewisi.【Methods】Transcriptome sequencing was conducted on the venom glands of adults and the 5th instar nymphs of P. lewisi collected from Qianxinan Prefecture, Guizhou Province using the high-throughput Illumina NovaSeq 6000 platform. The resulting data were annotated using the NR, NT, Pfam, KOG/COG, Swiss-Prot, KEGG and GO databases. Gene expression in the venom gland samples of P. lewisi was assessed using the FPKM method, and DESeq was employed for the differential expression analysis of venom gland transcriptomes between adult and the 5th instar nymph. The differentially expressed genes (DEGs) between the adult and the 5th instar nymphal venom gland transcriptomes were screened using the criteria of |log₂(Fold change)|>1 and P<0.05, followed by GO functional enrichment analysis and KEGG pathway enrichment analysis of the identified DEGs. The 33 215 transcripts obtained from the sequenced venom gland transcriptomes of adults and the 5th instar nymphs of P. lewisi were subjected to BLAST comparisons in the UniProt database.【Results】Transcriptome sequencing of the venom glands of adults and the 5th instar nymphs of P. lewisi assembled to 22 242 unigenes with an average length of 949 bp. A total of 15 364 unigenes were annotated to the NR, NT, Pfam, Swiss-Prot, GO, KOG/COG and KEGG databases, corresponding to 10 closely related species including three species of true bugs and two species of spiders. A total of 344 DEGs were screened between the venom gland transcriptomes of adults and the 5th instar nymphs of P. lewisi, with 218 genes up-regulated and 126 genes down-regulated. A total of 443 sequences encoding 33 distinct types of toxin-related proteins were identified.【Conclusion】The transcriptome data from the venom glands of both the 5th instar nymphs and adults of P. lewisi were sequenced and obtained in this study. Differential proteins between the venom gland transcriptomes of adults and the 5th instar nymphs were screened, and sequences associated with toxin proteins were identified. This research lays a theoretical foundation for the identification of components in the venom of P. lewisi and the investigation of their biological functions.

【Aim】 To address the issue of low transfering rate of sperm after artificial insemination of Apis cerana cerana and to extend the time during which inseminated queens lay fertilized eggs within the colony.【Methods】 A. c. cerana gynes at 7 d after eclosion were inseminated with 1, 3 and 5 μL of semen. For each dosage, there were treatment groups and control groups, with 5 gynes in each group. After insemination, a plastic device was immediately fitted onto the end of abdomen of queen in the treatment group, while no plastic device was fitted onto the end of abdomen of queen in the control group. After 24 h, the number of sperms in the spermatheca of each queen was counted. 【Results】Physical isolation via the fitted plastic device significantly improved the transferring rate of sperm of A. c. cerana to spermatheca after artificial insemination. It demonstrated a particularly notable advantage under low semen dosage, with the transferring rate of sperm increasing from approximately 11% under conventional artificial insemination to 43%. This effectively extended the time during which the queen laid fertilized eggs within the colony. The application of this method successfully elucidated the inheritance pattern of body color in A. c. cerana, demonstrating that body color is controlled by a pair of alleles, with yellow being dominant and black recessive. The three castes in the offspring resulting from the backcrossing of the heterozygous queen (F ₁) with the black drone exhibited a stable 1∶1 segregation ratio of body color, consistent with Mendelian inheritance. 【Conclusion】 The optimized sperm transfer method developed in this study significantly enhances the transferring rate of sperm of A. c. cerana from lateral oviduct to spermatheca in artificially inseminated queens, particularly under low semen dosage, such as single-drone insemination. This method can be successfully applied in the study of the inheritance pattern of body color, providing both a theoretical foundation and technical support for the selective breeding and germplasm conservation of A. c. cerana.

【Aim】In recent years, extreme weather events have increased markedly in frequency in China and globally, with many regions experiencing substantially prolonged periods of elevated summer temperatures. During field surveys, we unexpectedly discovered a rare wild yellow morph of Acyrthosiphon pisum, but its biological characteristics remain uncharacterized. This study aims to investigate the ecological adaptability and survival risks of this novel color morph of A. pisum under intensified climate change, with the goal of providing a theoretical foundation for elucidating the evolutionary mechanisms of A. pisum and informing future population management and biological control strategies.【Methods】The competitive abilities of the wild yellow morph of A. pisum against those of the red and green morphs of A. pisum on three host plants (Vicia faba, Vicia sativa, and Medicago sativa) were first compared, and the starvation tolerance of apterous viviparous adults across all the three morphs of A. pisum under conditions of food deprivation were evaluated. The three color morphs of A. pisum were subsequently subjected to repeated high-temperature stress (35 ℃ for 2 h per day until adult stage) beginning at the 1st instar nymphal stage, and the changes in their population decline rates and fecundity were detected at the adult stage. Finally, the predation risk of the 3rd instar nymphs of each color morph of A. pisum by adult female Coccinella septempunctata was assessed, and the color differences (ΔE) between the body surfaces of the 3rd instar nymphs of various morphs of A.pisum and the leaves of V. faba leaves were analyzed.【Results】The yellow morph of A. pisum showed significantly lower competitive abilities than the red and green morphs of A. pisum on V. faba and M. sativa, but occasionally attained a competitive advantage over the red morph of A. pisum on V. sativa. Compared with the other color morphs of A. pisum, the yellow morph of A. pisum demonstrated greater starvation tolerance. After heat shock treatment (35 ℃ for 2 h per day), the numbers of aphids produced by the yellow morph of A. pisum in 6 d on its native host V. sativa and the high-nutrient host V. faba were 23.83 and 31.67 individuals, respectively, which represented relatively low values as compared with those of the other two morphs of A. pisum. Specifically, these values were lower than those observed in the green morph of A. pisum on V. sativa and the red morph of A. pisum on V. faba (28.67 and 41.67 individuals, respectively). In contrast to its disadvantage in fecundity, the yellow morph of A. pisum exhibited population decline rates of 32.78% and 26.11% on V. sativa and V. faba, respectively, after heat shock treatment, both of which were lower than those recorded for the red morph of A. pisum (67.22% and 38.89% on V. sativa and V. faba, respectively) and the green morph of A. pisum (44.43% and 42.22% on V. sativa and V. faba, respectively). The color difference (ΔE) between the body surfaces of the 3rd instar nymphs of the yellow morph of A. pisum and the leaves of V. faba was 52.26, significantly greater than those between the body surfaces of the 3rd instar nymphs of the red morph of A. pisum and the leaves of V. faba (37.69), and between the body surfaces of the 3rd instar nymphs of the green morph of A. pisum and the leaves of V. faba (17.76). The yellow morph of A. pisum was more vulnerable to predation by C. septempunctata adults, with the population decline rates exceeding 49.00%.【Conclusion】The yellow morph of A. pisum exhibits distinct ecological adaptation strategies. Although the yellow morph of A. pisum is disadvantaged in competition and more vulnerable to predation, its enhanced starvation tolerance and thermal resistance may provide a fitness advantage under increasingly frequent extreme weather events.

【Aim】 This study aims to sequence the complete mitochondrial genomes of representative species of Chaitophorinae, so as to analyze the mitochondrial genome architecture and explore the phylogenetic relationships of Chaitophorinae.【Methods】High-throughput sequencing of five species (Chaitophorus populeti, Chaitophorus populifolii, Chaetosiphella stipae, Periphyllus lyropictus and Sipha flava) from four genera within Chaitophorinae was performed using Illumina platform, mitochondrial genome assembly and annotation were then carried out. Comparative analyses were conducted along with previously reported Chaitophorinae mitochondrial genomes of six species (Periphyllus diacerivorus, Periphyllus koelreuteriae, Chaitophorus saliniger, Chaetosiphella stipae, Periphyllus acerihabitans and Laingia psammae) from four genera in NCBI. Phylogenetic trees were reconstructed for Chaitophorinae and its relatives based on 37 gene sequences of 27 complete mitochondrial genomes using maximum likelihood (ML) approach and Bayesian inference (BI). 【Results】 The mitochondrial genomes of Chaitophorinae are 15 787-17 770 bp in size, including 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes, a non-coding control region, and a non-coding repeat region. No gene rearrangement was observed. The nucleotide composition of the Chaitophorinae mitochondrial genomes displays a strong bias toward A+T. All PCGs initiate with standard ATN codons. cox1 and nad4 terminate with T--, except for cox1 in Periphyllus lyropictus, which terminates with TAA, and other PCGs use TAA or TAG as stop codons. atp8 has undergone positive selection and displays the fastest evolutionary rate, whereas cox1 exhibits the slowest evolutionary rate. Except for trnSAGN, which lost the dihydrouridine (DHU) arm, all tRNA genes can form the typical clover-leaf secondary structures. The control region located between rrnS and trnI varies in length from 606 to 1 710 bp, and some species of Chaitophorinae contain repeat sequences in this region. The repeat region situates between trnE and trnF, ranging from 544 to 1 876 bp in length and is composed of species-specific repeat units. The structural composition of the repeat sequences within the control region and the repeat region differs, and the sequence similarity of the repeat units within these two regions is low. Phylogenetic analyses supported the monophyly of Chaitophorinae and its two tribes, Siphini and Chaitophorini. Within Siphini, Sipha flava was placed at the most basal position of this clade. Within Chaitophorini, the monophyletic Chaitophorus and Periphyllus formed a sister group.【Conclusion】In this study, the complete mitochondrial genomes of representative species of Chaitophorinae were sequenced and analyzed. All examined species have the species-specific repeat region between trnE and trnF, which may be a common feature of the Chaitophorinae mitochondrial genomes. Mitochondrial genomes are effective in resolving the phylogenetic relationships within Chaitophorinae. Our study provides valuable molecular data resources for a better understanding of the characteristics of Chaitophorinae mitochondrial genomes, as well as the phylogenetic relationships and evolutionary history of this group.

 Mutualism between microorganisms and animals plays a crucial part in the adaptation and evolution of hosts. Phloem-feeding aphids engage in intimate symbiotic associations with a variety of symbionts. Many aphid species cause enormous damage to crops, fruit trees, forest trees and medicinal plants, and some of them are important worldwide quarantine pests. Studies on aphid symbionts will advance our knowledge of symbiotic relationships between organisms and provide theoretical guidance for green pest management. Almost all aphid species harbour the primary symbionts to supply nutrients such as essential amino acids and vitamin B lacking in their diets. Secondary symbionts are closely related to the ecological adaptation of aphids. In this review, we outlined the species, tissue localization, transmission modes, and functions of aphid symbionts, and systematically summarized the species composition of symbiont communities in different groups of Adelgidae, Phylloxeridae and Aphididae. To date, most studies on aphid symbiont diversity have focused on different biotic and abiotic factors influencing the symbiont community structure, including aphid species, biological characteristics, evolutionary history, host plants, geographical distribution, and environmental factors (e.g., temperature). In the future, research should undertake extensive surveys of symbiont diversity across a greater variety of aphid taxa, enhance attention to gut symbionts, explore the relative contributions of stochastic and deterministic processes in the assembly of aphid symbiont communities, identify core symbionts and their biological functions, and focus on the potential application of key symbionts in RNAi-based biopesticides, so as to facilitate the development of efficient and environmentally friendly aphid pest management strategies.

【Aim】 Insects will express heat shock proteins (HSPs) efficiently to establish self-protection mechanism under high temperature and pesticide stress. This study aims to know the molecular mechanisms of hsp70 and hsc70 mRNA expression in Aphis glycines under thermal and imidacloprid stress at the transcriptome level and look for the vulnerable spot, so to provide some theoretical basis for biological control. 【Methods】 We adopted the homology-based cloning, RACE technique and real-time fluorescent quantitative PCR methods to research the expression of hsp70 and hsc70 in the 4th instar nymphs of A. glycines at different heat shock time or different recovery time after heat shock and after treatment with different concentrations of imidacloprid. 【Results】 The hsp70 transcription level in the 4th instar nymphs of A. glycines increased first after heat shock at 37℃, reaching 10.36-fold as high as that of the control ( P<0.05) at 1 h after heat shock, and then declined little by little. The recovery time after heat shock significantly influenced the hsp70 expression quantity. The hsp70 of A. glycines was abundantly expressed immediately after heat shock, with the expression level of 8.78-fold as high as that of the control ( P<0.05), and then decreased to the control level, while the hsc70 expression quantity did not change significantly ( P>0.05). Treated with imidacloprid, the peak time of hsp70 and hsc70 expression quantity in the 4th instar nymphs of A. glycines varied with the concentration of imidacloprid and stress time, showing an obvious short-term effect with a downward trend after rising first. 【Conclusion】 The transcription level of hsp70 and hsc70 in A. glycines under imidacloprid stress increases. However, hsp70 and hsc70 in A. glycines subjected to heat shock have different transcription expression patterns: the high temperature induces the expression of hsp70, but has no obvious inductive effect on hsc70.

【Aim】 The objective of this research was to screen microsatellite loci which were available for population genetic research of the oriental fruit moth, Grapholita molesta in China. 【Methods】 The amplification stability and genetic polymorphism of 11 microsatellite loci previously reported in European populations of G. molesta and Cydia pomonella were characterized from 257 individuals from 12 geographic populations of China. The screened polymorphic microsatellite loci were then used for population genetic analysis of the G. molesta populations. 【Results】 The results showed that loci Gm01, Gm03, Gm04 and Cyd15 could not be amplified from the samples. Gm05 could be amplified from a low proportion of individuals. Gm07 could be stably amplified, but was weakly polymorphic. Loci Gm02, Gm06, Gm08, Gm09 and Gm10 showed high polymorphism and could be amplified stably. For the five polymorphic loci, the mean number of alleles ( N_A) ranged from 7.417 to 12.500, the values of mean observed heterozygosity ( H_o) and expected heterozygosity ( H_e) were from 0.366 to 0.655 and from 0.642 to 0.846, respectively, and the polymorphic information content ( PIC) was between 0.800 and 0.935. 【Conclusion】 We successfully selected five loci, i.e., Gm02, Gm06, Gm08, Gm09 and Gm10. High genetic diversity of G. molesta populations sampled in Shandong Province and Shaanxi Province was revealed by data from these five loci. These five loci can be used for further population genetics research of G. molesta populations from China.

【Aim】 This study aims to uncover the antioxidant defense mechanisms in Spodoptera liturae larvae infected by the fungus Nomuraea rileyi.【Methods】 We measured the changes in the activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in the infected larvae of S. litura at different instars and compared the influences of different inoculation approaches including spraying method and dipping method on antioxidase activities in the infected larvae. 【Results】 The POD activity was not detected in both the infected larvae and the non-inoculated larvae (the control) of S. litura. The activities of SOD and CAT in the infected larvae were significantly higher than those in the control at the early stages of infection. However, the activities of SOD and CAT in the infected 2nd and 3rd instar larvae dropped sharply after reaching the peak at 16 h after inoculation. The antioxidase activities in the infected 4th and 5th instar larvae kept a high level for a long time and then turned lower than those of the control at 60-72 h after infection. The activities of SOD and CAT in the infected larvae which were inoculated with dipping and spraying methods were significantly higher than those of the control, and the dipping method had a greater effect on antioxidase activities than the spraying method in the 2nd and 3rd instar larvae, but there was no significant difference in the effects on the antioxidase activities in the 4th and 5th instar larvae between the two methods. 【Conclusion】 The antioxidase activities in S. litura larvae are greatly affected by the infection of N. rileyi. The activities of SOD and CAT increase first, and then decrease, and the trend of the change is closely related to the developmental stage of the larvae. The dipping method has a stronger influence on the SOD and CAT activities in the 2nd and 3rd instar larvae than on those in the 4th and 5th instar larvae when the body integument inoculation quantities are at the similar level.

【Aim】 The rearing host affects biological characteristics of Trichogramma. In order to know the differences between Trichogramma japonicum Ashmead reared on Corcyra cephalonica (Stainton) eggs and reared on Chilo suppressalis (Walker) eggs in the control effect on Ch. suppressalis, and also the possibility of using Co. corcyra eggs as the alternative host of T. japonicum in the field, we observed the host preference and parasitization behavior of T. japonicum emerged from different rearing hosts, and investigated the effects of rearing host on the parasitization capacity of T. japonicum, so as to provide basic information for the control of rice borer with Trichogramma. 【Methods】 The host preference of T. japonicam reared on Co. cephalonica eggs (TjCc) and Ch. suppressalis eggs (TjCs), respectively, were observed in choice tests in the laboratory. The parasitization behavior and capacity of TjCc and TjCs on eggs of  Ch. suppressalisand Co. cephalonica, respectively, were investigated. 【Results】 TjCs preferred Ch. suppressalis eggs to Co.cephalonica eggs, while TjCc did not show preferences. The host searching time was not significantly affected by either rearing host or host for parasitization, and both the outside host examination time and ovipostion time were not significantly affected by rearing host. However, the outside host examination time of both TjCc and TjCs on Co. cephalonica eggs was significantly longer than that on Ch. suppressalis eggs. The parasitism rate (36.95%) on Ch. suppressalis eggs and the emergence rate (45.68%) of TjCs were lower, respectively, than those in other three combinations (TjCc-Cc, TjCc-Cs and TjCs-Cc) among which no significant differences were found. The longevity of emerged wasps was not significantly different among the four treatments. 【Conclusion】 The rearing host affects the host preference and parasitization capacity of T. japonicum, but does not affect the host searching ability and parasitization behavior of the wasp.

【Aim】 This study aims to determine the morphological and biological  characteristics of different developmental stages of Thaumantis hainana and to define its  host plant. 【Methods】 Female adults of T. hainana were collected from wild habitats and  put into triangular paper envelopes for laying eggs. Its larvae were bred with the obtained  eggs in an incubator under the conditions of 26℃, 40% relative humidity and 16L∶8D  photoperiod with Phoenix loureirii leaves. The morphological characteristics of larvae were  observed, and the body length and the width of head capsule of larvae of different instars  were recorded. Some morphological characteristics of other developmental stages were also  recorded. 【Results】 T. hainana exhibits complete metamorphosis with four developmental  stages including egg, larva, pupa and adult. Eggs are round and have a smooth surface. Eggs  are about 2.5-2.8 mm in diameter. The larva has 5 instars, and the body length and the  width of head capsule of the larva increase gradually with the increase of larval instar.  And it has hanging pupa. Adults do not show sexual dimorphism.【Conclusion】 This study  primarily clarified the morphological and biological characteristics of different  developmental stages of T. hainana， and defined P. loureirii as one of its host plants,  enriching the basic data of T. hainana.

【Aim】This study aims to master the occurrence patterns of aphids in the wheat growing areas of northwestern Shandong, North China, explore their resistance levels to commonly used insecticides, and evaluate the field control efficacy of these insecticides against wheat aphids, so as to provide theoretical support for rational insecticide application and resistance management in wheat aphid control. 【Methods】The resistance levels of the wingless adults of Sitobion avenae and Rhopalosiphum padi to six commonly used chemical insecticides of four categories［lambda-cyhalothrin (pyrethroid), imidacloprid, thiamethoxam and acetamiprid (neonicotinoids), pymetrozine (pyridine), and emamectin benzoate (semi-synthetic antibiotic)］ were determined using the residual film method in glass tube. Concurrently, the population dynamics of wheat aphids in the field in northwestern Shandong were monitored from 2022 to 2024. The field control efficacy of the above six chemical insecticides and five biopesticides (Bacillus thuringiensis, rotenone, matrine, azadirachtin and veratrine) against wheat aphids was evaluated in May 2023. 【Results】 Bioassay results indicated that S. avenae exhibited moderate levels of resistance to acetamiprid and imidacloprid, and the median lethal concentraltion (LC₅₀) values of acetamiprid and imidacloprid against the wingless adults of S. avenae in 3 h were 2.800 and 3.871 μg/cm², respectively. R. padi showed decreased sensitivity to acetamiprid and pymetrozine, moderate level of resistance to lambda-cyhalothrin，and high level of resistance to imidacloprid, and the LC₅₀values of acetamiprid, pymetrozine, lambda-cyhalothrin and imidacloprid against the wingless adults of S. avenae in 3 h were 0.022, 0.593, 3.065 and 2.782 μg/cm², respectively. Both aphid species remained sensitive to the other tested insecticides. Field surveys revealed a parabolic trend in aphid occurrence in the wheat growing area of northwestern Shandong, with peak populations typically observed in mid-to-late May followed by decline in aphid number. Field efficacy trials demonstrated that biopesticides generally exhibited lower control efficacy against wheat aphids than chemical insecticides. Thiamethoxam, lambda-cyhalothrin, acetamiprid, B. thuringiensis and rotenone exhibited rapid action, achieving >75% control efficacy against wheat aphids at 3 d after application, significantly higher than the other six agents. Thiamethoxam, pymetrozine, lambda-cyhalothrin and acetamiprid showed sustained control efficacy against wheat aphids (>85% at 10 d after application). Azadirachtin had slower initial action but good persistence, reaching 84.14% control efficacy against wheat aphids at 10 d after application. 【Conclusion】 Based on the aphid occurrence patterns and resistance levels in the wheat growing area of northwestern Shandong, controlling aphid populations during wheat heading and flowering stages is recommended. Rotational application of pyrethroid, neonicotinoid and pyridine insecticides is advised for wheat aphid management. Given their slower initial action but prolonged efficacy, pyridine insecticides should be applied during the early outbreak stage of aphids.

【Aim】 Brassica napus is one of the most important oilseed crops, and the average planting area is relative large in many provinces in China. Glucosinolate is the specific secondary metabolite in Brassicaceae plants. This study aims to ascertain whether the B. napus seeds with different glucosinolate and erucic acid contents affect the host location and propagation of pests on B. napus leaves. 【Methods】 Leaf-disc bioassay, cage experiment, and Y-tube olfactory test were used to analyze the host selection preference of Myzus persicae on six B. napus cultivars ［the high erucic acid-high glucosinolate cultivar ZY821 (control), and the low erucic acid-low glucosinolate cultivars (double-low cultivars) including ZS11, XN18, AGY558, AYK999 and MXY78］, and potted plant test was used to observe and determine the changes in individual number of M. presicae on plants of different B. napus cultivars. 【Results】There were no significant differences in the numbers of M. persicae adults and newborn nymphs on the six B. napus cultivars in cage experiment. In leaf-disc choice bioassay, more M. persicae adults fed on leaves of XN18 ［(25.50±2.21) individuals］ and ZS11 ［(24.70±1.57) individuals］, which were higher than the numbers of M. persicae adults on ZY821, AGY558, MXY78 and AYK999 leaves［(20.90±3.56), (14.80±1.78), (16.60±2.43) and (19.50±1.12) individuals, respectively］. In Y-tube olfactory test, M. persicae adults did not show host selection preference for six B. napus cultivars. In potted plant test, there was no significant difference in the total individual number of M. persicae after ten adults were released on plants of six B. napus cultivars on the 7th and 14th day. On the 21st day, the total individual numbers of M. persicae on plants of five double-low B. napus cultivars ZS11, XN18, AGY558, AYK999 and MXY78 (244.50±15.39, 235.67±50.60, 163.60±28.67, 237.40±16.57 and 237.20±12.35), respectively］ were higher than that in the control group［ZY821: (156.00±35.12)］, but the total individual number of M. persicae on ZS11 plants was significantly higher than that on ZY821 plants. 【Conclusion】 Double-low B. napus cultivars can affect the population dynamics of M. persicae at the seedling stage, but they have relatively limited effects on the host location behavior of M. persicae.

Rearing of Anomala corpulenta Motschulsky were conducted in the laboratory condition and the main influencing factors were evaluted. The results showed that it took 274.3 days for the beetle to complete a life cycle in the laboratory conditions. The duration of the 3rd instar reared in the laboratory was 101.8 days shorter than that in fields. The growth of larvae was influenced by such factors as soil humidity, food and pathogens. The average survival rate of eggs was 86.0% while those of the 1st instar, 2nd instar and 3rd instar larvae were 82 . 0%, 76.0% and 60.0%, respectively. The mortalities of the 10 day-old and 15 day-old larvae reared in the soil with potato as food for 14 days were 8.8 ％± 1.6% and 4.0 ％± 1.6% respectively, significantly lower than those for the newly hatched larvae and 5 day-old larvae. This result suggested that the larval age of 10 － 15 day-old was the optimum stage for bioassay of Bt. The larvae grew normally in the UV-irradiated loam and sandy loam soil, with their mortalities lower than that in the untreated and sterilized loam and sandy loam soil.

According to the homologous amino acid sequences in Caenorhabditis elegans and other insects, the full length cDNA sequences of 3 glycosyltransferase genes (named as Pxbre-3, Pxbre-4 and Pxbre-5) were cloned by RT-PCR and RACE-PCR from the midgut of 4th instar larvae of the diamondback moth, Plutella xylostella. The open reading frames of these genes were 1 383 bp, 1 230 bp and 1 041 bp, respectively. The deduced coding products had 460, 409 and 346 amino acids, respectively. These genes were homologous to the bre genes of Caenorhabditis elegans and had the predicted membrane-spanning regions and conserved motifs known to play key catalytic roles in glycosyltransferases. Thus, the three genes are inferred to code glycosyltransferases in P. xylostella. The mRNA expression of these three genes and Pxbre-2 was detected in different developmental stages (larva, pupa, and adult) of P. xylostella by real-time quantitative PCR, and the expression level was higher in pupa and adult. These results provide an important basis for investigating the possible involvement of glycosylphingolipid in resistance to Cry toxins in P. xylostella.

The green ash, Fraxinus pennsylvanica Marsh., is infested with a leafcurl ash aphid in Beijing, China. Colonies of compact aphids live in curled leaves on the tips of twigs throughout the vegetation period. It causes malformations and some curled leaves turn to yellow. It was identified as an alien species, the Nearctic species Prociphilus fraxinifolii  (Riley, 1879). This is the first record of the species in China. The present paper described its diagnostic characteristics and recorded five predatory natural enemies ( Harmonia axyridis, Chrysopa pallens, Episyrphus balteata, Deraeocoris punctulatus and Deraeocoris ater) and three attending ants ( Camponotus japonicus, Formica fusca, and Lasiu s niger) of this aphid found in Beijing.

【Aim】 The estrogen-related receptor (ERR) via regulating the glycolytic cyclecan control the energy metabolism in Drosophila melanogaster. Based on the cloning of ERR gene ( BmERR) from the silkworm, Bombyx mori, its molecular property and phylogeny were bioinformatically analyzed, and the expression of the ERR gene in the silkworm was detected. This study may lay the foundation for further research on the function of ERR in Lepidoptera and provide ideas for pest control. 【Methods】 PCR technique was used to clone the cDNA sequence of BmERR gene, and the sequence was bioinformatically analyzed with online resources. The semi-quantitative RT-PCR was further applied to analyze its expression profiles in gonads of B. mori larvae stopping feeding. 【Results】 The full-length cDNA of BmERR has a 1 296 bp open reading frame, which encodes a 431-amino-acid-residue protein with a typical structural domain feature of the ERR protein family. Phylogenetic analysis indicated that the BmERR protein shows high amino acid sequence identity with the ERR proteins from other insects. RT-PCR detection showed that BmERR was expressed in both testis and ovary in wandering to pupal B. mori, and possessed apparent time specificity, with a peak expression at the first day after pupation. 【Conclusion】 The cloned ERR encoding sequence is reported for the first time in Lepidoptera. The expression of the ERR gene in the silkworm gonads has no significant gender difference, but with developmental stage specificity.

【 Aim 】 Circular RNA (circRNA) plays a key role in alternative splicing, transcription regulation and expression regulation of source genes. This study aims to analyze the quantity, variety, structural characteristics and function of circRNAs in the midgut of Apis mellifera ligustica workers, and to explore the regulatory function of circRNAs via constructing and analyzing regulatory networks. 【 Methods 】 A. m. ligustica workers were reared under laboratory conditions, and the midgut samples from 7 - and 10 - day - old workers were subjected to deep sequencing using circRNA - seq technology. CircRNAs were predicted from sequencing data after quality control using find_circ software. Source genes of these circRNAs were annotated to GO and KEGG databases to gain function and pathway annotations via BLAST. The target mRNAs of circRNAs and miRNAs were predicted with TargetFinder software, and the regulatory networks between circRNAs and miRNAs and between circRNAs, miRNAs and mRNAs were constructed and visualized using Cytoscape v.3.2.1software. The predicted circRNAs were validated by RT - PCR with the divergent and convergent primers designed. 【 Results 】 Sequencing of midgut samples from A. m. ligustica workers produced a mean of 136 463 071 clean reads, and for each sample over 136 779 122 anchor reads were obtained after removing rRNA. A total of 10 833 circRNAs were predicted, and their length ranged mainly from 15 to 1 000 nt. The types of these circRNAs were abundant, and the largest one was annotated to be exonic circRNA. The number of circRNAs distributed on chromosome 1 of Apis mellifera was the most and that distributed on chromosome 8 was the second. The source genes of circRNAs could be annotated to 45 GO terms including binding, cellular process, and cell, as well as 121 KEGG metabolic pathways including endocytosis, protein processing in endoplasmic reticulum, and ribosome, suggesting that circRNAs may play key roles in such biological processes as growth, development, metabolism, and cellular activity in the midgut of A. m. ligustica workers. Furthermore, the regulatory networks between circRNA and miRNA and between circRNA, miRNA and mRNA were constructed, and the analysis result demonstrated that partial circRNAs could bind microRNAs as competitive endogenous RNAs (ceRNAs). Finally, the true existence of randomly selected three circRNAs was validated by RT - PCR. 【 Conclusion 】 In this study, we predicted, analyzed, and verified circRNAs in the midgut of A. m. ligustica workers. Our findings provide the data of the quantity, variety, structural characteristics, roles, and regulatory network of circRNAs in the midgut, indicating that circRNAs can play roles in the developmental and immune defense processes in the midgut of A. m. ligustica workers through affecting source genes and acting as ceRNAs. This study lays a foundation for further studying the roles of circRNAs in the development and stress response of the midgut of A. m. ligustica.

 Reactive oxygen species (ROS) is a general term for a class of oxygen-containing free radicals formed due to incomplete oxidation of oxygen molecules, or peroxides that are easy to form oxygen free radicals. When insects are invaded by pathogens, the ROS defense system mediated by dual oxidase (DUOX) will respond quickly to produce a large amount of ROS to resist the invasion of pathogenic bacteria, and then play a role in regulating the immune defense process of insects. However, high level of ROS can damage the biological macromolecules such as proteins, DNA and lipids in cells, causing damage to insect cells and affecting the normal development of insects. In order to avoid damage from excessive oxidative stress, insects have formed a complete antioxidant defense system mainly composed of antioxidant enzymes and small molecule antioxidants to prevent excessive damage from occurring. It is interesting that changes in ROS levels in cells can play completely different roles in regulating insect lifespan: for certain insects the accumulation of a large amount of ROS could lead to a shortened lifespan, while for some other insects the presence of high physiological levels of ROS could also induce diapause and prolong their lifespan. Studies on the regulatory mechanisms of ROS in insect lifespan have achieved a lot of progress in recent years. Therefore, in this article, we comprehensively reviewed the sources and influencing factors of insect ROS, the defense mechanisms mediated by ROS, and for the first time made a summary and outlook on the specific roles of ROS in regulating insect lifespan, so as to provide a reference for subsequent research on ROS-related topics.

【Aim】This study aims to make clear the sublethal effects of the botanical insecticides azadirachtin and celangulin on Ostrinia furnacalis larvae and their effects on the activities of detoxification enzymes, so as to explore the detoxification mechanism of O. furnacalis on these two pesticides. 【Methods】The toxicity of azadirachtin and celangulin to the 3rd instar larvae of O. furnacalis in 72 h was analyzed by dipping method. The 3rd instar larvae of O. furnacalis were exposed to sublethal concentrations (LC₁₀, LC₂₀ and LC₄₀) of azadirachtin and celangulin for 6, 12, 24, 48 and 72 h, and the activities of three main detoxification enzymes including glutathione S-transferase (GST), carboxylesterase(CarE) and cytochrome P450(CYP450) were measured by enzyme-linked immunosorbent assay (ELISA). 【Results】 TheLC₁₀, LC₂₀ and LC₄₀ values of azadirachtin against the 3rd instar larvae of O. furnacalis in 72 h were 0.352, 0.614 and 1.290 mg/L, respectively, and those of celangulin against the 3rd instar larvae of O. furnacalis in 72 h were 0.032, 0.086 and 0.321 mg/L, respectively. After the 3rd instar larvae of O. furnacalis were exposed to LC₁₀, LC₂₀ and LC₄₀ of azadirachtin, the GST activity was firstly inhibited, then induced, and finally inhibited, and 12-h exposure to LC₁₀ of azadirachtin had an induction effect on the GST activity. LC₁₀, LC₂₀ and LC₄₀ of azadirachtin mainly inhibited the activities of CarE and CYP450. After the 3rd instar larvae of O. furnacalis were exposed to LC₁₀, LC₂₀ and LC₄₀ of celangulin, the activities of GST and CarE were mainly inhibited, and the CYP450 activity was firstly inhibited and then induced, while 72-h exposure to LC₁₀ of celangulin had an induction effect on the CYP450 activity. 【Conclusion】Azadirachtin and celangulin can affect the detoxification metabolism of O. furnacalis, and the inhibition of azadirachtin and celangulin on the activities of GST, CarE and CYP450 in O. furnacalis is one of the reasons for their insecticidal activity, GST only plays a certain role in metabolism on low concentration (LC₁₀)  of azadirachtin and CYP450 only plays a certain role in metabolism on low concentration (LC₁₀)  of celangulin.

【Aim】In order to more systematically reveal the transmission mode of banana bunchy top virus (BBTV) in the transmission vector Pentalonia nigronervos. 【Methods】Non-viruliferous P. nigronervos adults were allowed to acquire BBTV by feeding on infected plants of Musa acuminata AAA Groups, Cavendish cv. Baxi for 6, 12, 24, 36, 48 and 72 h. Then the expression levels of coat protein (CP) genes in these P. nigronervos adults were detected using PCR and qPCR to determine the virus acquisition time of non-viruliferous P. nigronervos. The distribution of BBTV in various tissues within the digestive system of P. nigronervos adults was observed through immunofluorescence detection and in situ hybridization, and the presence of BBTV in the honeydew of P. nigronervos and in Solenopsis invicta adults fed on this honeydew was detected by PCR.【Results】The expression of BBTV CP gene could be detected in P. nigronervos adults at 6 h after virus acquisition. Fluorescent labeling result indicated that BBTV was predominantly located in the anterior midgut (specifically in epithelial cells and circular muscles), accessory salivary glands, and excretory ostium of P. nigronervos adults. In situ hybridization result confirmed the presence of BBTV in the foregut, anterior midgut (epithelial cells), and principal salivary glands of P. nigronervos adults. PCR result revealed that the fragments of all six genetic components of BBTV could be detected in the honeydew secreted by viruliferous P. nigronervos as well as in S. invicta adults fed on this honeydew. 【Conclusion】A portion of BBTV acquired by P. nigronervos from banana bunchy top disease (BBTD) infected banana plants is transmitted in a persistent-nonpropagative circulative manner within the salivary glands, foregut, anterior midgut (epithelial cells and circular muscles), and excretory ostium of P. nigronervos adults. Conversely, another portion of BBTV is eliminated from the body of P. nigronervos in the form of honeydew. This study enhances our understanding of BBTV distribution in its transmission vector P. nigronervos and further confirms that BBTV spreads in its vector in a persistent-circulative manner. These findings are crucial for advancing research on the virus transmission mechanisms in P. nigronervos and for developing effective disease prevention and control strategies.

【Aim】 To ascertain the resistance levels of the field populations of Rhopalosiphum padi from the Guanzhong Region of Shaanxi Province, nothwestern China to five pyrethroid insecticides and analyze the correlations between the mutation frequencies of the voltage-gated sodium channel (VGSC) gene (the target gene of pyrethroid) of various field populations and resistance levels. 【Methods】Nine field populations of R. padi were collected from the Guanzhong Region of Shaanxi Province during April-June in 2023 and 2024 and the susceptibility of the apterous adults to five pyrethroid insecticides (bifenthrin, permethrin, lambda-cyhalothrin, deltamethyrin and fenvalerate) was tested by leaf-dipping method. PCR was used to detect the types and frequencies of VGSC gene mutation of various field populations of R. padi. The correlation between the mutation frequency and the resistance level (resistance ratio, RR) was analyzed. 【Results】Bioassay results revealed that the apterous adults of various field populations of R. padi exhibited varying degrees of resistance to five pyrethroid insecticides. The apterous adults of the population collected from Xingping County, Xianyang City in 2023 (XP-2023) showed the highest resistance levels to type Ⅰ pyrethroid insecticides (bifenthrin and permethrin), with the RRs of 76.1 and 52.3, respectively. The apterous adults of the populations collected from Fufeng County, Baoji City in 2024 and 2023 (FF-2024 and FF-2023) and the population collected from Liquan County, Baoji City in 2023 (LQ-2023) showed the highest resistance levels to type Ⅱ pyrethroid insecticides (lambda-cyhalothrin, deltamethrin and fenvalerate), with the RRs of 60.7, 97.5 and 42.6, respectively. Detection of VGSC gene mutations revealed that, except for the populations collected from Wugong County, Xianyang City and Qishan County, Baoji City, respectively, in 2023 (WG-2023 and QS-2023), all the field populations carried heterozygous mutation (M918L) in the VGSC gene, with the mutation frequencies ranging from 5.0% to 47.5%. The mutation frequency of M918L was significantly correlated with the level of resistance to pyrethroid insecticides. 【Conclusion】The M918L heterozygous mutation in the VGSC gene is significantly correlated with the resistance levels of the field populations of R. padi to pyrethroid insecticides, indicating that this target mutation plays an important role in the resistance of the field populations of R. padi to these insecticides. It is recommended to minimize or avoid the use of pyrethroid insecticides in field control of R. padi and to continuously monitor the resistance levels of field populations.