Please wait a minute...
Information
  • Monthly, Founded in 1950
    Supervisor:Chinese Academy of Sciences
    Sponsor:Institute of Zoology,Chinese Academy of Sciences
    The Entomological Society of China
    Domestic postal code: 2-153
    Foreign issuance code: Q61
    ISSN 0454-6296
    CN 11-1832/Q
Table of Content
20 September 2024, Volume 68 Issue 9
For Selected: View Abstracts Toggle Thumbnails
  • RESEARCH PAPERS
    Physiological responses of silicon-treated rice plants to feeding stress by the white-backed planthopper, Sogatella furcifera (Hemiptera: Delphacidae)
    HAN Yong-Qiang, XIE Mei-Qiong, LI Dan-Dan, XUE Zhi-Ping
    2025, 68(9):  1175-1183.  doi:10.16380/j.kcxb.2025.09.001
    Abstract ( 27 )   PDF (1469KB) ( 16 )     
    Related Articles | Metrics
    【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 (O2), 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 O2 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.
    Effects of exogenous juvenile hormone on the female ovarian development and transcription levels of the reproduction-key genes in Spodoptera frugiperda (Lepidoptera: Noctuidae)
    HAN Shi-Peng, WANG Xiao-Qi, HAN Hui, WANG Da, HE Yun-Zhuan
    2025, 68(9):  1184-1192.  doi:10.16380/j.kcxb.2025.09.002
    Abstract ( 31 )   PDF (9089KB) ( 28 )     
    Related Articles | Metrics
    【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.
    RNAi effect and functional analysis of tropomyosin gene HaTm-1 of Helicoverpa armigera (Lepidoptera: Noctuidae)
    GUAN Ruo-Bing, HAN Rui, CHU Dong-Dong, XU Sai-Bo, LIU Xiao-Guang, LI Xiang
    2025, 68(9):  1193-1202.  doi:10.16380/j.kcxb.2025.09.003
    Abstract ( 4 )   PDF (1917KB) ( 13 )     
    Related Articles | Metrics
    【Aim】 This study aims to conduct tissue expression profile and RNAi effect analyses of tropomyosin gene of Helicoverpa armigera HaTm-1,  previously identified through transcriptome screening, so as to explore the feasibility and theoretical basis of HaTm-1 as a broad-spectrum RNA biopesticide target for lepidopteran pests. 【Methods】 The cDNA sequence of HaTm-1 of H. armigerawas cloned using PCR and analyzed through bioinformatics. RT-qPCR was used to detect the expression levels of HaTm-1 in different tissues of the 4th instar larvae, including cuticle, fat body, midgut, brain, testis and Malpighian tubules, as well as in the cuticle of the 2nd-5th instar larvae of H. armigera. RNAi of HaTm-1 was performed by spraying dsHaTm-1 on the 1st instar larvae of H. armigera and Spodoptera frugiperda. The expression levels ofHaTm-1 of H. armigera and HaTm-1 of S. frugiperda, and the larval weight and larval survival rate of these species were subsequently measured. dsHaTm-1 was injected into the 4th instar larvae of H. armigera, and the larval weight, pupal weight, relative growth rate, relative metabolic rate and food intake were detected. 【Results】 The full-length cDNA of HaTm-1 of H. armigera was 855 bp (GenBank accession no.: XP021201113.1). HaTm-1 had the amino acid sequence identity of over 90% with homologous proteins in multiple species. Tm-1s of H. armigera and S. frugiperda converged on the same clade, suggesting a close relationship between them. HaTm-1 was specifically and highly expressed in the cuticle of the 4th instar larvae of H. armigera and was also expressed in the cuticle at different larval instars, with peak expression occurring in the cuticle of the 5th instar larva. There was a decrease in the expression level of HaTm-1 by 55.73% and 50.85% at 12 and 24 h, respectively, a significantly reduced larval survival rate by 43.33% at 168 h, and decrease in the larval weight by 17.67%, 14.65% and 18.90% at 72, 120 and 168 h, respectively, after spraying dsHaTm-1 to the 1st instar larvae of H. armigera, as compared with those in the dsEGFP control group. The expression level of SfTm-1 decreased by 44.72% and 39.65% at 12 and 24 h, respectively, after spraying dsHaTm-1 on the 1st instar larvae of S. frugiperda as compared with those of the dsEGFP control group. The larval survival rate was observed to be 60% at 144 h after spraying dsHaTm-1 on the 1st instar larvae of S. frugiperda. The larval weight decreased by 13.00% and 28.11% at 72 and 120 h, respectively, after spraying dsHaTm-1 on the 1st instar larvae of S. frugiperda as compared with those of the dsEGFP control group. The expression level of HaTm-1 was significantly reduced by 55.66% at 24 h, the larval weight was decreased by 50.34% and 54.91%, respectively, at 72 and 120 h, the pupal weight was reduced by 13.14%, the relative growth rate was decreased by 14.00%, the relative metabolic rate was decreased by 15.66% and the food intake was decreased by 14.50%, after injecting the 4th instar larvae of H. armigera with dsHaTm-1 as compared with those of the dsEGFP control group. These alterations in feeding and digestion processes ultimately resulted in larval death. 【Conclusion】 The interference of HaTm-1 expression is vital to the feeding and digestion processes in H. armigera. This study underscores the potential of tropomyosin as a broad-spectrum target for RNA biopesticides, offering valuable insights for its practical application.
    Analysis of structures and expression patterns of the TAX family genes in the pine wood nematode, Bursaphelenchus xylophilus (Nematoda: Aphelenchoididae)
    JI Dang-Cheng, YU Hui-Zhi, FENG Hong-Xing, XIONG Zhong-Ping, MA Ling, HAO Xin, CHEN Jie
    2025, 68(9):  1203-1211.  doi:10.16380/j.kcxb.2025.09.004
    Abstract ( 8 )   PDF (2282KB) ( 6 )     
    Related Articles | Metrics
     【Aim】This study aims to investigate the chemotaxis and thermotaxis of Bursaphelenchus xylophilus, by analyzing the physicochemical properties, structure and functions of the members of TAX family and the expression of TAX family gene Bx-taxs after drug and low-temperature stresses. 【Methods】Based on the NCBI database, the TAX family gene sequences of Caenorhabditis elegans were retrieved and compared with B. xylophilus genome for tBlastn to search candidate TAX family genes in B. xylophilus. The candidate sequences were screened and cleaned by software and online tools such as ExPASy, WoLF PSORT, SOPMA, Alphafold 3, MEME, CD-Search and TBtools, and Bx-taxs of B. xylophilus were identified and the gene structure and chromosomal localization, and the subcellular localization, sequence features, physicochemical properties, secondary structure and tertiary structure of their proteins were analyzed. A phylogenetic tree of TAX protein sequences was constructed by IQtree software to infer phylogenetic relationships. The expression profiles of six Bx-taxs were analyzed to determine the roles of Bx-taxs by subjecting B. xylophilus to emamectin benzoate drug stress and low-temperature stress. 【Results】A total of six members of the TAX family, Bx-TAX-1-6, were identified from B. xylophilus. These proteins had 623-1 115 amino acid residues, relative molecular masses of 71.49-129.27 kD, and theoretical isoelectric points of 5.68-9.04, most of them being hydrophilic proteins. All six TAX family members were located on the cell membrane, especially the Bx-TAX-1 protein was also distributed in the cytoplasm. The secondary structures of the TAX family proteins were mainly composed of α-helixes and random coils, accounting for 42.10%-53.07% and 32.38%-45.80%, respectively. Chromosomal localization and phylogenetic analyses showed that TAX family genes of B. xylophilus were distributed on four chromosomes of which genes were closer to the TAX-4 genes of other nematodes, except for the Bx-TAX-1 gene, which was a separate branch. Under emamectin benzoate stress, all genes of the members of TAX family showed different degrees of down-regulation of expression within 12 h, and up-regulation of expression at 24 h. Among them, the expression levels of Bx-tax-3, Bx-tax-5 and Bx-tax-6 were up- or down-regulated by more than 1-fold. Only Bx-tax-5 was up-regulated under low-temperature stress, while the others were down-regulated. 【Conclusion】 TAX family genes of B. xylophilus show varying degrees of response to emamectin benzoate and low temperature stresses. The results of this study provide a theoretical basis for chemical and temperature tropism studies based on the TAX family, and provide a research basis for B. xylophilus response to chemical stress and its northward migration mechanism.
    Role of the salivary protein α-galactosidase A gene TuGLA in female adults of Tetranychus urticae (Acari: Tetranychidae) during feeding
    CHEN Shi-Si, AN Qi, WANG Chao, LÜ Jing-Jing, LIU Lei, LIU Huan, WANG Sen-Shan, SUN Qin-Zhe, SONG Li-Wen
    2025, 68(9):  1212-1221.  doi:10.16380/j.kcxb.2025.09.005
    Abstract ( 12 )   PDF (2289KB) ( 11 )     
    Related Articles | Metrics
    【Aim】 α-Galactosidase A (GLA), an enzyme crucial for growth and development, nutrient absorption and stress response of organisms, has been extensively studied in both animals and plants. However, the function of GLA in mites has not been reported. This study aims to explore the role of GLA gene in the feeding process of Tetranychus urticae on its host plants, providing important theoretical insights for the development of novel pest mite control strategies. 【Methods】 Based on the genome and salivary proteome of T. urticae, the full-length open reading frame (ORF) sequence of TuGLA was obtained, and bioinformatic analysis was performed using Expasy, Clustal, Jalview and MEGA. RT-qPCR was used to detect the expression levels of TuGLA at different developmental stages (egg, larva, protonymph, deunymph and female adult) of T. urticae, and in female adults of T. urticae at different feeding time points (1, 3, 6, 9, 12 and 24 h) on kidney bean leaves and at 12 h after feeding on different host plant leaves (kidney bean, tomato, cucumber, corn, cotton and tobacco). RNAi was employed to silence TuGLA by feeding female adults of T. urticae with dsTuGLA, and subsequently the mortality within 5 d and number of eggs laid within 5 d, and the feeding damaged area of kidney bean leaves were calculated. 【Results】 The full-length coding sequence (CDS) of TuGLA (GenBank accession number: XP_015794636.1) of T. urticae is 1 275 bp, encoding 424 amino acids, with a predicted protein molecular weight of 48 kD and a theoretical isoelectric point of 5.01. The 1st-18th amino acids at the N-terminus are signal peptide sequences of TuGLA without transmembrane domains. TuGLA was most closely related to GLAs in Tetranychus genus. TuGLA was expressed in various developmental stages of T. urticae, with the highest expression level in the adult stage. The expression level of TuGLA in female adults of T. urticae at 9 h after feeding on kidney bean leaves was the highest and those in female adults of T. urticae at 12 h after feeding on leaves of tomato, cucumber, corn, cotton and tobacco were significantly up-regulated as compared with those in female adults of T. urticae at 12 h after feeding on kidney bean leaves of the control group. After silencing TuGLA, the mortality within 5 d and the number of eggs laid within 5 d of female adults of T. urticae were significantly increased and reduced, respectively, and the feeding damaged area of kidney bean leaves within 24 h significantly decreased after silencing TuGLA as compared to the those of the dsGFP control group. After silencing TuGLA, the mortality of T. urticae fed on the leaves of kidney bean within 3 d significantly increased as compared with that of the dsGFP control group.【Conclusion】 The feeding on different host plants and feeding duration by T. urticae can induce the expression of TuGLA. Silencing TuGLA by RNAi can significantly affect the survival rate and number of eggs laid of T. urticae, and its damage to host plants. The results of this study provide a theoretical basis for further exploring the feeding mechanism of T. urticae.
    Diversity and functions of symbiotic bacteria in bacteriomes, fat bodies and testes of adult Tettigetta isshikii (Hemiptera: Cicadidae)
    GUO Qiong, ZHOU Jin-Rui, HAN Xiao-Hong, LIU Lu, WEI Cong
    2025, 68(9):  1222-1232.  doi:10.16380/j.kcxb.2025.09.006
    Abstract ( 7 )   PDF (37822KB) ( 20 )     
    Related Articles | Metrics
    【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.
    Optimization of cellulase production conditions of composite bacterial consortia constructed with the gut-derived cellulose-degrading bacteria from Allomyrina dichotomus (Coleoptera: Scarabaeidae) and assessment of their degradation efficiency for spent mushroom substrate
    ZHU Lian, JIA Jin-Shan, LI Sen-Duo, WU Jun-Hao, HE Yi-Jun, ZHANG Jun-Jie, DU Wen-Mei, HU Ying
    2025, 68(9):  1233-1241.  doi:10.16380/j.kcxb.2025.09.007
    Abstract ( 6 )   PDF (3518KB) ( 6 )     
    Related Articles | Metrics
     【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.
    SPINK7 recognizes and aggregates bacteria to initiate Bombyx mori blood cells-mediated immune defenses against bacterial infections
    AN Ling-Na, LI Zhuo-Yu, ZHANG Yan, GUO Peng-Chao, GUO Kai-Yu, LIU Wen-Yue, DONG Zhao-Ming, ZHAO Ping
    2025, 68(9):  1242-1250.  doi:10.16380/j.kcxb.2025.09.008
    Abstract ( 21 )   PDF (7363KB) ( 11 )     
    Related Articles | Metrics
    【Aim】 To elucidate the biological function of serine protease inhibitor Kazal-type 7 (SPINK7) and its immunorecognition mechanism of Bombyx mori against bacterial infestation. 【Methods】 Bioinformatics analysis of SPINK7 of B. mori was made followed by prokaryotic expression, and the secondary structure and heat resistance of SPINK7 were analyzed by circular dichroism. The tendency of SPINK7 to form aggregates was detected by non-reducing electrophoresis and Western blot. The 5th instar larvae of B. mori were infected by Escherichia coli and Staphylococcus aureus, respectively, and the expression levels of SPINK7 gene in hemocytes and fat bodies were detected by qPCR, and the SPINK7 content in serum was detected by Western blot. The inhibitory activities of SPINK7 against E. coli, S. aureus and Micrococcus luteus were analyzed by bacterial inhibition curves. The binding of SPINK7 to pathogen-associated molecular patterns (PAMPs) such as peptidoglycan and lipopolysaccharide, and the binding of SPINK7 to E. coli, S. aureus and M. luteus were detected by immunofluorescence localization and enzyme-linked immunosorbent assay (ELISA).【Results】 SPINK7 consists of three conserved Kazal structural domains, each of which contains six cysteines, forming three pairs of disulfide bonds. The secondary structure of SPINK7 is mainly α-helix, which is consistent with the typical secondary structure of Kazal structural domains, it is heat-resisting and remains structurally stable at 80 ℃. After induction by E. coli and S. aureus, SPINK7 formed a multimeric structure, and the expression levels of SPINK7 gene in hemocytes and fat bodies and the SPINK7 content in the serum of the 5th instar larvae of B. mori were significantly up-regulated, as compared with those of the phosphate buffer solution (PBS) control group. SPINK7 did not directly inhibit bacterial activity, and promoted bacterial aggregation by binding to bacterial PAMPs. 【Conclusion】SPINK7 is a Kazal-type immune-associated protein, whose expression is up-regulated and multimerized after bacterial infestation in B. mori, and helps hemocytes to aggregate bacteria and exert immune effect by recognizing and binding to bacterial PAMPs.
    Regulatory role and expression pattern of Ascosphaera apis ass-milR0037-3p in the guts of Apis cerana cerana and Apis mellifera ligustica worker larvae
    YE Dao-You, ZANG He, WANG Meng-Yi, FAN Nian, WU Tao, ZHENG Ke-Xin, YAN Ti-Zhen, LU Zhao-Hui, XIE Run-Gui, CHEN Da-Fu, GUO Rui, QIU Jian-Feng
    2025, 68(9):  1251-1260.  doi:10.16380/j.kcxb.2025.09.009
    Abstract ( 6 )   PDF (2971KB) ( 15 )     
    Related Articles | Metrics
    【Aim】The purpose of this study is to detect the expression patterns of ass-milR0037-3p and its key target genes in worker larvae of Apis cerana cerana and A. mellifera ligustica in the process of Ascosphaera apis infection, so as to offer a foundation for further exploring the mechanism of ass-milR0037-3p regulating the As. apis infection. 【Methods】 The target genes of ass-milR0037-3p of As. apis were predicted using related software and then annotated to GO and KEGG databases. Stem-loop RT-PCR and RT-qPCR were employed to verify the expression of ass-milR0037-3p in the guts of the 6-day-old worker larvae of Ap. c. cerana and Ap. m. ligustica and to detect the expression levels of ass-milR0037-3p and its two key target genes (genomic protein acetyltransferase gene ESA1 and flavin containing amine oxidase gene FAO) in the guts of the 4-6-day-old worker larvae after feeding the 3-day-old worker larvae of Ap. c. cerana and Ap. m. ligustica with diets containing 1×107 spores/mL As. apis, respectively.【Results】 ass-milR0037-3p could target 225 genes annotated to 28 GO terms such as reproduction, binding and cells, as well as 105 KEGG pathways such as splicing, biosynthesis of secondary metabolites, and amino sugar and nucleotide sugar metabolism. The target fragments of ass-milR0037-3p were amplified in the guts of the 6-day-old worker larvae of both Ap. c. cerana and Ap. m. ligustica infected with As. apis. The expression levels of ass-milR0037-3p in the guts of the 5- and 6-day-old worker larvae of Ap. c. cerana infected with As. apis were significantly up-regulated and the expression levels of ESA1 and FAO in the guts of the 5- and 6-day-old worker larvae of Ap. c. cerana infected with As. apis were significantly down-regulated, as compared with those of the 4-day-old worker larvae of Ap. c. cerana infected with As. apis. The expression level of ass-milR0037-3p in the gut of the 5-day-old worker larvae of Ap. m. ligustica infected with As. apis was up-regulated as compared with that of the 4-day-old worker larvae of Ap. m. ligustica infected with As. apis and that of the 6-day-old worker larvae of Ap. c. cerana infected with As. apis was significantly up-regulated as compared with that of the 4-day-old worker larvae of Ap. m. ligustica infected with As. apis. The expression levels of the target genes ESA1 and FAO in the gut of the 5-day-old worker larvae of Ap. m. ligustica infected with As. apis were up-regulated and those of the 6-day-old worker larvae of Ap. m. ligustica infected with As. apis were significantly up-regulated as compared with those of the 4-day-old worker larvae of Ap. m. ligustica infected with As. apis.【Conclusion】 ass-milR0037-3p potentially modulates the process of As. apis infecting worker larvae of Ap. c. cerana by negatively regulating the FAO expression, while potentially affects the process of As. apis infecting worker larvae of Ap. m. ligustica through positively regulating the ESA1 expression. The results provide a basis for elucidating the mechanism by which milRNAs respond to the As. apis infection of honeybee larval guts via regulating the expression of target genes.
    Effects of sublethal concentrations of azadirachtin and celangulin on the activities of detoxification enzymes in Ostrinia furnacalis (Lepidoptera: Crambidae)
    WANG Xiao-Xi, WANG Yu, WANG Ke-Qin, LIU Xing-Long
    2025, 68(9):  1261-1269.  doi:10.16380/j.kcxb.2025.09.010
    Abstract ( 10 )   PDF (1491KB) ( 13 )     
    Related Articles | Metrics
    【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.
    Effects of fourteen insecticides on the safety and predatory efficiency of the natural enemy Picromerus lewisi (Hemiptera: Pentatomidae)
    LI Wen-Hong, TIAN Xu, JIN Jie, YANG Can, SUN Zhi-Rong, HUANG Chun-Yang, WANG Han-Cheng
    2025, 68(9):  1270-1281.  doi:10.16380/j.kcxb.2025.09.011
    Abstract ( 25 )   PDF (1915KB) ( 11 )     
    Related Articles | Metrics
    【Aim】To explore the safety of commonly used insecticides to the natural enemy Picromerus lewisi and their impact on predation function.【Methods】The spraying method was applied to detect the median lethal concentration (LC50) values of 14 insecticides of 6 categories [broflanilide, cyantraniliprole, chlorantraniliprole and flubendiamide (diamides), lambda-cyhalothrin (pyrethroids), imidacloprid, flupyradifurone and sulfoxaflor (neonicotinoids and analogues), triflumezopyrim (mesoionics), emamectin benzoate, spinosad and abamectin (macrolides), and bioinsecticides (Bacillus thuringiensis and Metarhizium anisopliae CQMa421)] against the 3rd instar nymphs of P. lewisi, and the safety factor was used to evaluate their safety to P. lewisi. In addition, the predatory efficiency of the 3rd instar nymphs of P. lewisi treated with four insecticides mentioned above (lambda-cyhalothrin, cyantraniliprole, imidacloprid and abamectin) on the 2nd and 3rd instar larvae of Mythimna seperata was analyzed using the disc equation. 【Results】Chlorantraniliprole, cyantraniliprole and abamectin exhibited relatively high safety levels to the 3rd instar nymphs of P. lewisi, and flubendiamide demonstrated the highest safety to the 3rd instar nymphs of P. lewisi, with the LC50 value of 369.71 mg/L in 24 h and the safety factor of 7.39. In contrast, lambda-cyhalothrin, imidacloprid and broflanilide exhibited lower safety to the 3rd instar nymphs of P. lewisi, and broflanilide showed the lowest safety to the 3rd instar nymphs of P. lewisi, with the LC50 value of 0.01 mg/L in 24 h and the safety factor of below 0.01. After 48-h treatment, sulfoxaflor, chlorantraniliprole, flubendiamide and cyantraniliprole maintained relatively high safety to the 3rd instar nymphs of P. lewisi, and flubendiamide was recorded to have the highest safety to the 3rd instar nymphs of P. lewisi, with the LC50 value of 299.28 mg/L and the safety factor of 5.99. Conversely, broflanilide, imidacloprid and lambda-cyhalothrin exhibited lower safety to the 3rd instar nymphs of P. lewisi, and broflanilide had the lowest safety to the 3rd instar nymphs of P. lewisi, with the LC50 value of 0.04 mg/L in 48 h and the safety factor of below 0.01. The bioinsecticides M. anisopliae CQMa421 and B. thuringiensis were found to be relatively safe to the 3rd instar nymphs of P. lewisi. Compared to the control treated with 0.1% Triton X-100, the stress from the four insecticides (lambda-cyhalothrin, cyantraniliprole, imidacloprid and abamectin) reduced the predation efficiency of the 3rd instar nymphs of P. lewisi, although had no significant effect on the instantaneous attack rate. Notably, under the stress of 20 mg/L cyantraniliprole, the 3rd instar nymphs of P. lewisi had the highest instantaneous attack rates (0.623 and 0.586, respectively) on the 2nd and 3rd instar larvae of M. seperata.  Under the stress of 2 mg/L abamectin, the 3rd instar nymphs of P. lewisi nymphs had the shortest handling time for prey (0.091 and 0.076 d, respectively), the highest maximum daily predation amount (11.00 and 13.12 individuals, respectively) and the highest predatory efficiency (4.72 and 5.34, respectively) on the 2nd and 3rd instar larvae of M. seperata, while under the stress of 2 mg/L imidacloprid, the 3rd instar nymphs of P. lewisi had the lowest predation efficiency (2.46 and 2.08, respectively) on the 2nd and 3rd instar larvae of M. seperata. 【Conclusion】Chlorantraniliprole, flubendiamide and M. anisopliae CQMa421 demonstrated higher safety to P. lewisi nymphs, whereas broflanilide and imidacloprid exhibited lower safety to P. lewisi nymphs. Additionally, treatments with abamectin and cyantraniliprole had minimal impact on the predation capability of P. lewisi nymphs, while imidacloprid treatment significantly affected their predation capability. These findings play a crucial role in providing information for pest management strategies in agricultural environments by minimizing the toxicity of insecticides.
    Prediction of adult emergence dynamics of the overwintering generation of Chilo suppressalis (Lepidoptera: Crambidae)
    DAI Chang-Geng, ZHONG Yu-Qi, CHENG Yi-Yu, ZHAO Lan, GONG You-Hui, HOU Mao-Lin
    2025, 68(9):  1282-1292.  doi:10.16380/j.kcxb.2025.09.012
    Abstract ( 9 )   PDF (1567KB) ( 9 )     
    Related Articles | Metrics
    【Aim】Prediction of the adult emergence dynamics of the overwintering generation of Chilo suppressalis is crucial for the accurate prediction and control of its offspring generations. This study aims to develop a model simulation for predicting the adult emergence dynamics of the overwintering generation of C. suppressalis.【Methods】To obtain model parameters, the overwintering larval populations of C. suppressalis were collected from the paddy fields in Xing′an, Guangxi, South China in February, March and April 2021 and the developmental duration of immature stages and adult emergence rate were determined at four temperatures (14, 18, 22 and 26 ℃). The developmental rates of immature stages (the reciprocal of developmental duration) were fitted with linear and nonlinear models, and the adult emergence rate was fitted using a three-parameter Weibull equation. Model parameters were calculated using Origin 2022.【Results】From the perspective of model fitting, the model established based on the developmental duration of immature stages and adult emergence rate data of the overwintering larval population of C. suppressalis collected in March performed better (Radj2March=0.9445, Radj2February=0.9083, Radj2April=0.8380). However, the field observation data showed that the nonlinear larval development Schoolfield model {V(T)=0.64×T/298.15×exp[47.11/1.99×(1/298.15-1/T)]} and the adult emergence Weibull equation {F∑(V(T))=1-exp[-(∑V(T)+0.04)/1.05)×5.95]} based on the overwintering larval population collected in February gave the least deviation of adult emergence dynamics between the predicted value and the field-observed value, which was 1.0-5.3 d. 【Conclusion】In practical application, local air temperature data are input into the above models to obtain the predicted adult emergence dynamic values of the overwintering generation of C. suppressalis, which, when corrected by the deviation values obtained in this study, will provide accurate prediction of adult emergence dynamics and aid in the decision-making for the accurate control of C. suppressalis.
    Reproductive development state and field dynamics of Loxostege sticticalis (Lepidoptera: Pyralidae) adults trapped by sex pheromone and floral scent
    WU En, ZHAO Su-Mei, YU Feng-Ling, SUN He, HE Shu-Ya, XUE Zhi-Ping, HE Shuang-Shuang, DENG Feng-Zhi, HUANG Jun-Xia, DU Yong-Jun
    2025, 68(9):  1293-1304.  doi:10.16380/j.kcxb.2025.09.013
    Abstract ( 13 )   PDF (14089KB) ( 13 )     
    Related Articles | Metrics
    【Aim】To explore the feasibility and theoretical basis of using sex pheromone and floral scent trapping as monitoring methods for Loxostege sticticalis adults. 【Methods】The developmental status of female ovaries and male testes of L. sticticalis moths trapped by sex pheromone, floral scent and net catching were investigated, dissected and analyzed in the field, and the relationships between the egg quantity, number of trapped moths and the number of field survey populations, and the migration status were analyzed. 【Results】The testes of male moths of L. sticticalis were closely related to the day-old age, and the regression equation was y=1.289-0.1288x+0.003516x2. Field experiments conducted in Kangbao, Hebei during 2020-2023, revealed that when sex pheromone traps successfully captured male moths, the mating rates of female moths were 66.7%-100%, and the proportions of level Ⅳ ovaries were 44.1%-95.4%. When the male moths could not be trapped, the mating rates of female moths were 0%-30.3%, and the level Ⅳ ovaries accounted for 0%-3.6%. From June 12 to June 22, 2024, the average mating rate of female moths trapped by floral scent (94.3%±2.3%) was significantly higher than that of female moths trapped by net catching (76.2%±5.3%) in Dashimen Town, Hexigten Banner, Inner Mongolia Autonomous Region. There was no difference in the average number of matings between female moths trapped by floral scent and by net catching. The number of egg grains remaining in the ovaries of female moths trapped by floral scent was (169.8±15.4), which was significantly lower than the that of female moths trapped by net catching (267.9±20.7). The average testicular volume of the male moths caught by sex pheromone trapping was the largest [(0.21±0.01) mm3], followed by that trapped by net catching [(0.19±0.02) mm3], and that trapped by floral scent was the smallest [(0.15±0.01) mm3]. The number of L. sticticalis adults trapped by sex pheromone and floral scent was closely related to their physiological state. Adults attracted by sex pheromone were male moths searching for mates, while those caught by floral scent trapping were female moths which have mated and laid part of eggs, as well as male moths which have mated. Therefore, male moths of the immigrant population and local breeding population of L. sticticalis were sensitive and had strong responses to sex pheromones, while the ovarian development level of female moths of the emigrant population was low, and the corresponding male moths were immature, and had no olfactory behavioral response to sex pheromones and floral scent. This relationship was verified by multiple field experiments in different seasons in Kangbao, Hebei and Hexigten Banner, Inner Mongolia from 2020 to 2024. 【Conclusion】 The combination of sex pheromone trapping and floral scent trapping can help determine the physiological state of L. sticticalis and estimate its migratory status and population dynamics of the next generation in the field.
    Optimization and application of methods for improving transfering rate of sperm of Apis cerana cerana (Hymenoptera: Apidae) after artificial insemination
    ZHUANG Ming-Sheng, LI Ji-Lian
    2025, 68(9):  1305-1312.  doi:10.16380/j.kcxb.2025.09.014
    Abstract ( 6 )   PDF (3342KB) ( 9 )     
    Related Articles | Metrics
    【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 (F1) 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.
    CONTENTS
    Contents of Vol. 68 Issue 9
    2025, 68(9):  1313-1313. 
    Abstract ( 7 )   PDF (561KB) ( 10 )     
    Related Articles | Metrics