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  • 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
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Photo shows a nymph and a female adult of the white-backed planthopper, Sogatella furcifera (Hemiptera: Delphacidae), feeding on leaf sheath of host plant Oryza sativa. S. furcifera is a serious piercing-sucking insect pest infesting O. sativa, Zea mays and other graminaceous plants, and also the vector of Southern rice black-streaked dwarf virus. In this issue, the identification of salivary gland proteins of nymph [Detail] ...
Current Issue
20 March 2021, Volume 64 Issue 3
RESEARCH PAPERS
Identification of salivary gland proteins of nymphs and male and female adults of Sogatella furcifera (Hemiptera: Delphacidae)
LI Fei, YI Jin-Yu, LIU Yu-Di, HOU Mao-Lin
2021, 64(3):  281-301.  doi:10.16380/j.kcxb.2021.03.001
Abstract ( 91 )   PDF (2815KB) ( 73 )   PDF(mobile) (2815KB) ( 20 )     

 【Aim】 To identify and functionally annotate the salivary gland proteins of Sogatella furcifera and to explore their differences and correlation between different developmental stages and sexes. 【Methods】 Proteins were extracted from salivary gland tissues dissected from anesthetized nymphs, and male and female adults of S. furcifera, subjected to reductive alkylation and enzymolysis, and identified by liquid chromatography tandem mass spectrometry. Then, the salivary gland proteins were functionally annotated and classified by comparison with the Unigene protein database and KOG analysis. 【Results】There were 385, 168 and 82 salivary gland proteins specifically associated with nymphs, and male and female adults of S. furcifera, respectively. In total 319 salivary gland proteins were shared by nymphs and male adults, 60 by nymphs and female adults, and 60 by male and female adults. The KOG functional annotation showed the highest number of proteins associated with cellular processes and signaling, with 81, 22, and 70 proteins of this type specifically associated with nymphs, male adults, and female adults, respectively, and 19, 21 and 12 proteins of this type shared by nymphs and male adults, nymphs and female adults, and male and female adults, respectively, and these proteins are principally involved in post-translational modification, protein turnover, chaperones, intracellular trafficking, secretion and vesicular transport, and signal transduction.【Conclusion】 The salivary gland proteins of S. furcifera are quite active in signal transduction, which may be connected to its piercing and sucking damage to host plants.

  Dynamic distribution of histone H3 Ser10 phosphorylation during meiosis in spermatocytes of the silkworm, Bombyx mori
ZHANG Bing, QIU Reng, KAN Yun-Chao
2021, 64(3):  302-308.  doi:10.16380/j.kcxb.2021.03.002
Abstract ( 94 )   PDF (8355KB) ( 33 )   PDF(mobile) (8355KB) ( 6 )     
【Aim】 To explore the function of histone H3 Ser10 phosphorylation  (H3Ser10ph) during meiosis in spermatocytes of the silkworm, Bombyx mori. 【Methods】 The testis tissues of B. mori from the 4th instar larval stage to pupal stage weredissected and separated. The slides of testis tissues at different stages of meiosis in spermatocytes were prepared by encapsulation of acrylamide gel and then the localization characteristics of the H3Ser10ph antibody was detected by using immunofluorescence staining. 【Results】 The phosphorylation of histone H3 Ser10 occurred in the specific position of pachytene chromosomes during meiosis in eupyrene spermatocytes of B. mori. The signal of H3Ser10ph was gradually weakened in the diplotene, and no phosphorylation signal was detected in the chromosomes at the diakinesis. With the progress of cell cycle, phosphorylation signal began to increase, and reached the highest level at the metaphase of the first meiosis. When the cells entered the prometaphase II of meiosis, the signal of H3Ser10ph on the chromosome arm disappeared, and there was holo-shaped fluorescent signal of the H3Ser10ph antibody close to the spindle microtubulin attaching side. At the end of meiosis II, a weak H3Ser10ph signal remained in the specific position of chromatin. During apyrene spermatocyte meiosis, the signal of H3Ser10ph was aggregated uniformly along the whole chromosomes from metaphase I to telophase I, and the spindle microtubules were parallel to the equatorial plane at anaphase I. 【Conclusion】 Histone H3 Ser10 phosphorylation is correlated with the dynamic changes of chromatin in eupyrene spermatocytes and apyrene spermatocytes of the silkworm. 
Exploration of the function of the gametogenetin binding protein gene Bmggnbp2 in Bombyx mori by CRISPR/Cas9 binary transgenic system
LIU Hong-E, WANG Li-Zhi, LIU Zu-Lian, YI Mei-Yan, FENG Qi-Li, HUANG Yong-Ping, XIANG Hui
2021, 64(3):  309-317.  doi:10.16380/j.kcxb.2021.03.002
Abstract ( 14 )   PDF (8663KB) ( 22 )   PDF(mobile) (8663KB) ( 0 )     
【Aim】 Gametogenetin binding protein 2 (ggnbp2) plays an important role in mammalian gametogenesis. In this study, we used Bombyx mori as a model to explore the biological function of the domesticated gene ggnbp2, so as to provide clues for the further study of this gene in lepidopteran insects. 【Methods】 The sequences of ggnbp2 genes in lepidopteran insects were retrieved from the NCBI GenBank by blast, and the phylogenetic analysis of the ggnbp2 genes was made through constructing the phylogenetic tree by Bayesian method. Based on the genomic polymorphism data of B. mori and B. mandarina populations established in our previous study, the selection signal of Bmggnbp2 in B. mori was analyzed, and the tissue expression pattern of Bmggnbp2 in the day-3 5th instar larvae of B. mori was analyzed based on the published gene chip data. The Bmggnbp2  knockout mutants were constructed in the binary transgenic system CRISPR/Cas9, and the differences in the reproductive traits (number of eggs laid per female and egg hatching rate) between the mutant and the control line Nos-Cas9 and the economic traits (cocoon weight, pupal weight and cocoon shell weight) between the mutants and the control lines U6-Bmggnbp2sgRNA and Nos-Cas9 were assayed and analyzed. 【Results】 ggnbp2 is widely distributed in lepidopteran insects and highly conserved, and has strong artificial selection signal in B. mori. Bmggnbp2 was highly expressed in the brain, ovary, testis and silk gland of the day-3 5th instar larvae of B. mori. The chimeric knockout mutant △Bmggnbp2 of Bmggnbp2 gene was successfully obtained by binary transgenic system CRISPR/Cas9. The testes of the control line Nos-Cas9 are typical reniform, while those of the mutant △Bmggnbp2 are oval in shape and have a thick yellow covering. The number of eggs laid per female and egg hatching rate between the mutant △Bmggnbp2 and the control line Nos-Cas9 and the cocoon weight, pupal weight and cocoon shell weight between the mutant Bmggnbp2 and the control lines U6-Bmggnbp2sgRNA and Nos-Cas9 showed no significant difference. 【Conclusion】 The effect of GGNBP2 on reproduction in lepidopteran insects may not be as important as that in mammals, and its action mechanism still needs to be further explored.
Expression patterns and pheromone-binding properties of the pheromone binding protein CpunPBP3 in Conogethes punctiferalis (Lepidoptera: Crambidae) (In English)
CHEN Qiu-Ying, YANG Xi, YOU Dong-Rui, YANG Mu, XU Zhi-Feng, XIAO Wei
2021, 64(3):  318-326.  doi:10.16380/j.kcxb.2021.03.004
Abstract ( 49 )   PDF (1706KB) ( 22 )   PDF(mobile) (1706KB) ( 5 )     

【Aim】 This study aims to better understand the sex pheromone perception mechanisms by identifying and characterizing a sex pheromone binding protein (PBP) in the yellow peach moth, Conogethes punctiferalis (CpunPBP3). 【Methods】 The cDNA sequence of CpunPBP3 of C. punctiferalis was amplified and analyzed, and the amino acid sequence was compared to those of the homologous proteins in other Crambidae species. The day-age-dependent changes and circadian fluctuations in the expression levels of CpunPBP3 in the male adult antenna of C. punctiferalis, and the changes in the expression level of CpunPBP3 in the antenna over 24 h-period following exposure of adult males to the sex pheromones E10-16∶Ald (150 ng) and Z10-16∶Ald (6 ng) were examined by qRT-PCR. The recombinant expression vector pET-30a(+)/CpunPBP3 was constructed, and the recombinant CpunPBP3 was expressed in Escherichia coli. The binding capacity of the purified recombinant protein CpunPBP3 with the above two sex pheromones was evaluated by fluorescence competitive binding assay. 【Results】 The phylogenetic analysis result revealed that CpunPBP3 and the previously identified C. punctiferalis PBP genes CpunPBP2 and CpunPBP5 clustered in different branches, but CpunPBP3 is similar to PBP genes in other insect species. The qRT-PCR results showed that the expression level of CpunPBP3 in the male adult antenna increased first and then decreased from day 0 to 8 after adult eclosion, with significantly higher expression level at 17∶00 than at 1∶00, but with no significant difference at other time points within 24-h photoperiod. However, the expression level of CpunPBP3 in the male adult antenna significantly decreased after induction by 150 ng E10-16∶Ald for 3 and 6 h, and significantly increased after induction by 6 ng Z10-16∶Ald for 6 and 24 h. Fluorescence competitive binding assay result showed that the recombinant CpunPBP3 had strong binding capacity with E10-16∶Ald and Z10-16∶Ald, with the Ki values of 9.267 and 8.656 μmol/L, respectively. 【Conclusion】 The study determined the nucleotide and amino acid sequences and the expression pattern of CpunPBP3, and CpunPBP3 was expressed in response to the sex pheromone induction. The recombinant CpunPBP3 has strong binding capacity with sex pheromone, indicating that CpunPBP3 is a sex pheromone binding protein in C. punctiferalis.

cDNA cloning, prokaryotic expression, and ligand binding characterization of the odorant binding proteins CpunOBP3 and CpunOBP4 of the yellow peach moth, Conogethes punctiferalis (Lepidoptera: Crambidae)
GUO Hong-Gang, WEI Chun-Hua, ZHANG Min-Zhao, QIN Xiao-Chun, DU Yan-Li
2021, 64(3):  327-336.  doi:10.16380/j.kcxb.2021.03.005
Abstract ( 42 )   PDF (1954KB) ( 24 )   PDF(mobile) (1954KB) ( 3 )     
【Aim】 This study aims to determine the physiological function of odorant binding proteins (OBPs) in the chemoreception of the yellow peach moth, Conogethes punctiferalis, so as to provide a theoretical basis for selecting OBPs that may be used as targets in C. punctiferalis biological control. 【Methods】 Two OBP genes (CpunOBP3 and CpunOBP4) were cloned from antennae of C. punctiferalis by PCR based on our previous antennal transcriptome data. The nucleotide and amino acid sequences of the two OBPs were analyzed with bioinformatics software. The recombinant  xpression vectors pET-30a/CpunOBP3 and pET-30a/CpunOBP4 were constructed. and the recombinant proteins CpunOBP3 and CpunOBP4 were obtained by prokaryotic expression and purification. The binding activity of the recombinant CpunOBP3 and CpunOBP4 to 24 ligands was analyzed by fluorescence competitive binding assay.【Results】 The open reading frame of CpunOBP3 gene (GenBank accession no.: GEDO010000010.1) is 387 bp in length, encoding a protein of 128 amino acids with the predicted molecular weight of 14.72 kD. The open reading frame of CpunOBP4 gene (GenBank accession no.: GEDO010000011.1) is 438 bp in length, encoding a protein of 145 amino acids. The predicted molecular weight of  CpunOBP4 without signal peptide is 12.82 kD. CpunOBP3 and CpunOBP4 share the typical structural features of OBPs, including six conservative cysteine residues. Both the recombinant CpunOBP3 and CpunOBP4 were mainly expressed in the inclusion. Fluorescence competitive binding assay indicated that the recombinant CpunOBP3 showed the binding ability to seven plant volatiles tested, with the strongest binding ability to 3-carene(Ki=10.33 μmol/L), but not to two sex pheromones tested. The recombinant CpunOBP4 exhibited the binding ability not only to the two sex pheromones tested (cis-10-hexadecenal with the Ki value of 14.65 μmol/L and hexadecanoyl with the Ki value of 7.83 μmol/L), but also to eight plant volatiles tested, with the strongest binding ability to ethyl butyrate (Ki=4.32 μmol/L). 【Conclusion】 Based on these results, we inferred that CpunOBP3 plays an important role in the host location and shift of C. punctiferalis, while CpunOBP4 possesses dual functions in recognizing sex pheromones and plant volatiles. The results provide a theoretic basis for controlling the occurrence and damage of C. punctiferalis via disturbing its olfactory reception.
Diversity and sequence characteristics of the OCT family genes in Anopheles sinensis (Diptera: Culicidae)
LEI Dan, YAN Zhen-Tian, ZHANG Xiao-Xiao, CHEN Bin
2021, 64(3):  337-347.  doi:10.16380/j.kcxb.2021.03.006
Abstract ( 30 )   PDF (7078KB) ( 19 )   PDF(mobile) (7078KB) ( 0 )     

 【Aim】 To identify, classify and name genes of the organic cation transporter (OCT) family of Anopheles sinensis at the whole-genome level, so as to provide an information frame for the OCT genes of insects. 【Methods】 The amino acid sequences encoded by OCT genes in An. gambiae, Drosophila melanogaster and Caenorhabditis elegans were downloaded from NCBI, VectorBase and EMBL databases, and used as queries to search for the OCT genes in An. sinensis genome using the local Blast program based on the genome and transcriptome sequencing data of An. sinensis. The characteristics of these OCT genes in An. sinensis, including the gene structure, Scaffold location and conservative motifs, were predicted using bioinformatics methods. The phylogenetic tree of OCT genes of An. sinensis was constructed by the maximum likelihood method. 【Results】 The An. sinensis genome contains 54 OCT genes, which are divided into three subfamilies, OCTA, OCTB and OCTC, with 33, 15 and 6 genes, respectively. The encoded OCT amino acid sequences, except for AsOCTA20 and AsOCTB2, have MFS_1 and Sugar_tr transmembrane domains (TMDs), and most of the OCT amino acid sequences have 12 TMDs. All the OCT amino acid sequences have three conserved motifs, GRK-(PT)-VL, PES-(APVS) and EQFPT-(VI)-RN, and each subfamily has its own conservative motifs. Four pairs of genes (AsOCTB4a and AsOCTB4b, AsOCTA10a and AsOCTA10b, AsOCTA19a and AsOCTA19b, and AsOCTA23a and AsOCTA23b) are derived from gene duplication events. AsOCTC genes are relatively primitive, while AsOCTB genes are relatively evolved, both forming an obvious monophyly. AsOCTA genes are between AsOCTC genes and AsOCTB genes in evolution, with more complicated evolutionary relationship. 【Conclusion】 This study enriches the genome data of An. sinensis, and lays the foundation for the subsequent research of the functions of OCT genes in An. sinensis, especially their functions in insecticide resistance mechanism.

Function of the cytoplasmic peptidoglycan recognition protein RfPGRP-L2 in maintaining the homeostasis of gut microbiota in Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) 
XIAO Rong, WANG Xing-Hong, LI Xiong-Wei, LIU Hui-Hui, LU Sheng-Ping, HOU You-Ming, SHI Zhang-Hong
2021, 64(3):  348-362.  doi:10.16380/j.kcxb.2021.03.007
Abstract ( 38 )   PDF (6142KB) ( 22 )   PDF(mobile) (6142KB) ( 7 )     

Abstract: 【Aim】 To determine the function of a cytoplasmic peptidoglycan recognition protein, RfPGRP-L2, in the maintenance and regulation of homeostasis of gut microbiota in the invasive insect pest, Rhynchophorus ferrugineus, so as to provide scientific basis and action targets for the development of new insect pest control strategies targeting to destroy the homeostasis of gut microbiota. 【Methods】 The sequence characteristics of RfPGRP-L2 were analyzed by bioinformatics methods. RT-qPCR was used to analyze the expression levels of RfPGRP-L2 in the different tissues (head, fat body, epidermis, foregut, mid-/hindgut and hemolymph) of the healthy 4th instar larvae of R. ferrugineus and in the gut and fat body of the 4th instar larvae of R. ferrugineus challenged with Escherichia coli DH5α and Staphylococcus aureus by injection with 1 μL bacterial suspension with the OD600 value of 1.6 and oral feeding with sugarcane slices smeared with 1 mL bacterial suspension with the OD600 value of 1.6, respectively. Prokaryotic expression of RfPGRP-L2 was carried out, and in vitro assays were applied to determine the agglutination and antibacterial activity of the recombinant RfPGRP-L2 to E. coli DH5α and S. aureus. After RNAi of RfPGRP-L2, the number of gut bacterial colonies of E. coli in the hemolymph and gut of the 4th instar larvae of R. ferrugineus was determined. The expression levels of antimicrobial peptide genes in the fat body and gut of the 4th instar larvae of R. ferrugineus after RNAi of RfPGRP-L2 were detected by RT-qPCR. By bacterial 16S rRNA-based high-throughput sequencing, the effect of RNAi of RfPGRP-L2 on the gut microbiota composition of the healthy 4th instar larvae of R. ferrugineus was analyzed.【Results】 The SMART analysis revealed that RfPGRP-L2 has no transmembrane domain and signal peptide, suggesting that RfPGRP-L2 is a cyoplasmic peptidoglycan recognition protein. The RT-qPCR results showed that RfPGRP-L2 was highly expressed in the immunity-related tissues, such as the hemolymph, gut and fat body of the healthy 4th instar larvae of R. ferrugineus. The expression level of RfPGRP-L2 in the fat body of the 4th instar larvae of R. ferrugineus was significantly up-regulated upon the challenge with injected E. coli and S. aureus for 6 h and 12 h, respectively. After oral feeding of E. coli for 6 h, the expression level of RfPGRP-L2 in the gut of the 4th instar larvae of R. ferrugineus was also increased significantly. Furthermore, in vitro assays revealed that the recombinant RfPGRP-L2 could result in the obvious agglutination of E. coli and S. aureus, suggesting that RfPGRP-L2 could recognize the two pathogenic bacteria. When RfPGRP-L2 was silenced in the 4th instar larvae of R. ferrugineus, the ability to clear the invaded EGFP-tagged E. coli in the gut and hemolymph was significantly impaired as compared to the control group, the expression level of antimicrobial peptide gene RfCecropin in the gut was significantly reduced, the number of gut bacterial colonies in the healthy 4th instar larvae was significantly increased compared to the control group, and the gut bacterial composition was also altered significantly. 【Conclusion】 The cyoplasmic peptidoglycan recognition protein RfPGRP-L2, acting as a pattern recognition receptor to discriminate pathogens and to activate the immune signaling pathways in intestinal epithelial cells, can promote the expression of antimicrobial peptide gene to modulate the homeostasis of gut microbiota in R. ferrugineus.

Differential expression analysis of full-length transcripts in mycelia and spores of Ascosphaera apis 
DU Yu, JIANG Hai-Bin, WANG Jie, FAN Xiao-Xue, WANG Xiu-Na, FENG Rui-Rong, ZHANG Wen-De, LONG Qi, XIONG Cui-Ling, ZHENG Yan-Zhen, CHEN Da-Fu, GUO Rui
2021, 64(3):  363-373.  doi:10.16380/j.kcxb.2021.03.008
Abstract ( 41 )   PDF (6644KB) ( 30 )   PDF(mobile) (6644KB) ( 7 )     

【Aim】 This study aims to investigate the correlation of the full-length transcripts in Ascosphaera apis mycelium (Aam) and spore (Aas) with the mycelium growth, spore germination and sexual reproduction. 【Methods】 The congruent information about the full-length transcripts and known transcripts was obtained by aligning the clean reads generated from the previously gained Nanopore long-read sequencing data of Aam and Aas to the known transcripts annotated in the reference genome of A. apis. Bioinformatics methods were used to analyze the differential expression pattern, functional annotation and structural characteristics of the full-length transcripts in Aam and Aas. 【Results】There were 19 966 full-length transcripts in both Aam and Aas. The specific full-length transcripts of Aam and Aas were 1 273 and 2 856, respectively. In the Aas vs Aam comparison group, 3 230 differentially expressed transcripts (DETs) including 3 072 up-regulated and 158 down-regulated transcripts were identified. These DETs involve such GO items as metabolic process, cell, catalytic activity, etc. KEGG pathway annotation analysis demonstrated that these DETs are involved in pathways including endocytosis, MAPK signaling pathway, glycolysis/gluconeogenesis, carbon metabolism, and amino acid biosynthesis. Further investigation indicated that the splicing isoforms of some full-length transcripts had different expression levels and structure in Aam and Aas. 【Conclusion】 In this study it was discovered that the expression levels and structure of transcripts in A. apis vary in the two stages of mycelium and spore. These results provide a theoretical and data foundation for deeply investigating the molecular function of various splicing isoforms involved in the mycelium growth, spore germination and sexual reproduction of A. apis.

Resistance selection and biological characteristics of Neoseiulus barkeri (Acari: Phytoseiidae) to chlorpyrifos
WANG Li, CHENG Ming-Ming, FU Yun-Mei, FANG Yun-Hong, WEI Zhi-Tang, CHENG Lu-Yan, LEI Shuang, DING Li-Li, YU Shi-Jiang, CONG Lin, RAN Chun
2021, 64(3):  374-383.  doi:10.16380/j.kcxb.2021.03.009
Abstract ( 33 )   PDF (1652KB) ( 13 )   PDF(mobile) (1652KB) ( 6 )     

 【Aim】 To clarify the effects of acquired chlorpyrifos resistance in the predatory mite Neoseiulus barkeri on its biological characteristics, so as to provide a theoretical basis for its field application. 【Methods】 The residual film method was adopted to test the toxicity of chlorpyrifos to N. barkeri in the laboratory, and the lethal medium concentration (LC50) was chosen as the selection pressure. Life table was used to assess the effects of acquired chlorpyrifos resistance on the relative fitness (Rf)of N. barkeri. In addition, Holling type II model was used to analyze the differences in the predation functional response of the chlorpyrifos-susceptible and resistant strains of N. barkeri to eggs and female adults of Panonychus citri at different temperatures.【Results】 A chlorpyrifos-resistant strain of N. barkeri with the resistance ratio of 34.77-fold was obtained after selection of 21 generations. The acquired resistance had no significant effects on the developmental duration, proportion of female offspring and predation functional response of N. barkeri, but shortened the female adult longevity and oviposition period. The susceptible and resistant strains of N. barkeri could not complete the whole generation at 15℃. The fecundity (number of eggs laid per female) of the susceptible and resistant strains of N. barkeri was the highest at 25℃, and the fecundity was significantly higher for the susceptible strain (41.64±1.04 eggs/female) than for the resistant strain (38.80±0.93 eggs/female). Likewise the oviposition periods of the susceptible and resistant strains of N. barkeri were the longest at 25℃, and the oviposition period was significantly longer for the susceptible strain (24.82±1.50 d) than for the resistant strain (21.34±1.26 d). Further, the shortest developmental duration of the susceptible and resistant strains of N. barkeri was recorded at 30℃, being 6.62±0.23 d for the susceptible strain and 6.53±0.13 d for the resistant strain. Meanwhile, the strongest predation ability of the susceptible and resistant strains of N. barkeri to eggs or female adults of P. citri was recorded at 30℃, with the daily maximum predation amounts of the susceptible and resistant strains of N. barkeri to P. citri eggs being 156.25 and 140.85, respectively, and to female adults of P. citri being 23.10 and 22.32, respectively. The relative fitness (Rf) of the resistant strain of N. barkeri was lower than that of the susceptible strain at 25 and 30℃, but slightly higher than that of the susceptible strain at 20 and 35℃. 【Conclusion】 Generally, chlorpyrifos resistance in N. barkeri has little effect on its biological characteristics under different temperatures. The study results provide a theoretical basis for screening resistant strains of N. barkeri and their field application.

Host adaptability of Bemisia tabaci on tomato plants with ToCV single infection and TYLCV&ToCV co-infection and the changes in the nutrient contents and defense responses of host plants
DING Tian-Bo, ZHOU Xue, YANG Nan, YANG Yang, TANG Yao, CHU Dong
2021, 64(3):  384-391.  doi:10.16380/j.kcxb.2021.03.010
Abstract ( 44 )   PDF (1519KB) ( 13 )   PDF(mobile) (1519KB) ( 2 )     

【Aim】 This study focuses on two important tomato viruses, tomato chlorosis virus (ToCV) and tomato yellow leaf curl virus (TYLCV). It aims to explore the effects of ToCV single infection and TYLCV&ToCV co-infection on the host adaptability of Bemisia tabaci MED, and to reveal the physiological mechanism from the perspective of host plant nutrient contents and defense responses. 【Methods】 After ToCV single infection andTYLCV&ToCV co-infection, the survival rates and number of eggs laid of B. tabaci MED adults on the infected tomato plants, and the contents of amino acids and total sugar in the infected tomato plants were detected. Additionally, the expression profiles of key genes related to jasmonic acid (JA) (FAD7 and PI II) and salicylic acid (SA) (NPR1 and PR1) signal pathways in tomato plants in response to ToCV single infection and TYLCV&ToCV co-infection were analyzed by RT-qPCR. 【Results】 The survival rate and number of eggs laid of B. tabaci MED adults feeding on the tomato plants infected by tomato viruses decreased significantly compared to those feeding on the healthy tomato plants. Feeding onthe TYLCV&ToCV coinfected tomato plants could reduce the survival rate and number of eggs laid of B. tabaci MED adults to the lowest level. The contents of total amino acids, fourteen types of hydrolyzed amino acids and total sugar in the TYLCV&ToCV co-infected tomato plants were significantly lower than those in the ToCV-singly infected tomato plants. The expression levels of FAD7 and PI II were significantly downregulated in tomato plants infected by ToCV and TYLCV&ToCV, and the expression levels of these two genes were the lowest in the TYLCV&ToCV co-infected tomato plants. However, the expression levels of NPR1 and PR1 were upregulated in tomato plants infected by ToCV and TYLCV&ToCV. The expression levels of NPR1 in the TYLCV&ToCV co-infected tomato plants and PR1 in the ToCV-singly infected tomato plants were all significantly higher than those in the healthy tomato plants. 【Conclusion】 Both ToCV single infection and TYLCV&ToCV co-infection could decrease the host adaptability of B. tabaci MED on tomato plants, and TYLCV&ToCV co-infection brought a more adverse effect on the survival of B. tabaci MED. Compared with the healthy tomato plants, the nutritional condition and defense system in ToCV-singly infected and TYLCV&ToCV co-infected tomato plants have obviously altered and are different between both. The results provide a basis for revealing the interaction between B. tabaci and plant viruses.

Effects of exogenous juvenile hormone on the diapause termination and post-diapause development of Chrysoperla sinica (Neuroptera: Chrysopidae)
HUANG Hai-Yi, ZHAO Yue-Ming, WU Xiao-Liang, CHEN Zhen-Zhen, XU Yong-Yu
2021, 64(3):  392-399.  doi:10.16380/j.kcxb.2021.03.011
Abstract ( 46 )   PDF (1354KB) ( 14 )   PDF(mobile) (1354KB) ( 5 )     

 【Aim】 The aim of this study is to clarify the effective doses of exogenous juvenile hormone (JH) and the optimal treatment period for rapid diapause termination in the green lacewing, Chrysoperla sinica. 【Methods】 The pre-oviposition period, oviposition duration, female longevity and number of eggs laid per female of diapause adults of C. sinica exposed to different doses of exogenous JH (0, 5, 15, 25 and 35 μg/adult) by topical application and the changes of these four indexes of diapause C. sinica adults treated at different day-old age (0, 5, 10, 20, 30 and 40 day-old) with 15 μg/adult exogenous JH were determined. 【Results】 The pre-oviposition period of the diapause adults of C. sinica exposed to 15 and 25 μg/adult exogenous JH was 6.82 and 6.29 d, respectively, significantly shorter than that (10.55 d) in the control group (only treated with acetone). The oviposition duration, female longevity and the number of eggs laid per female of the diapause adults of C. sinica exposed to 15 μg/adult exogenous JH were all the highest, significantly higher than those of the control group. After diapause C. sinica adults were exposed to 15 μg/adult exogenous JH at different day-old age, the pre-oviposition period of adults treated at 0, 5,10 and 20 day-old age was significantly shorter than that of the control group non-subjected to exogenous JH treatment, the oviposition duration and female longevity of the adults treated at 10, 20 and 30 day-old age showed no significant difference from those of the control group non-subjected to exogenous JH treatment, while the numbers of eggs laid per female of the adults treated at 10, 20 and 30 day-old age were significantly reduced as compared to the control group non-subjected to exogenous JH treatment. Both adults subjected and non-subjected to exogenous JH treatment at 20 day-old age had higher fecundity. 【Conclusion】 Considering all the four indexes of pre-oviposition period, oviposition duration, oviposition amount and female longevity, we recommend 15 μg/adult exogenous JH as the optimal dose for the rapid diapause termination of C. sinica. The optimal treatment period for rapid diapause termination is the adult diapaused for 20 d, which has the least effect on the reproductive ability of C. sinica adults. The bottleneck problem of long time needed for diapause termination of C. sinica has been solved in this study, providing a new idea for the efficient storage and utilization of natural enemies with adult diapause and the fast diapause termination.

Effects of host switch on the performance and lifetable parameters of host populations of Cnaphalocrocis medinalis (Lepidoptera: Pyralidae)
CHEN Ping, LIU Huan, HOU Mao-Lin
2021, 64(3):  400-408.  doi:10.16380/j.kcxb.2021.03.012
Abstract ( 30 )   PDF (3306KB) ( 18 )   PDF(mobile) (3306KB) ( 5 )     

【Aim】 The rice leaf folder (RLF), Cnaphalocrocis medinalis, as one of the migratory insect pests of rice, can also complete its development on corn. This study aims to determine the influence of host switch on the performance of host populations of C. medinalis. 【Methods】 The RLF corn population (RLF-cp) and rice population (RLF-rp) were fed with their original and switched host plants, respectively, resulting in four treatment combinations: RLF-cp feeding on corn, RLF-cp feeding on rice, RLF-rp feeding on corn and RLF-rp feeding on rice. The age-stage two-sex life tables of the RLF host populations of the four treatment combinations were established, and the performance and life table parameters of these RLF host populations were measured. 【Results】 The developmental duration of immature stage of RLF-rp feeding on rice was the longest (29.2 d), while that of RLF-cp feeding on rice was the shortest (24.8 d). The values of performance indexes (pupal weight, pupation rate, emergence rate, and fecundity), life table parameters (survival rate, maximum fecundity, maximum reproductive value, and immature life expectancy), and population parameters (intrinsic rate of increase, finite rate of increase, and net reproductive rate) of RLF-cp and RLF-rp feeding on corn were the highest while those of RLF-cp feeding on rice were the lowest (except for pupal weight), and those of RLFrp feeding on corn were higher than those of RLF-rp feeding on rice.【Conclusion】 Performance and population growth of the corn population of C. medinalis decrease significantly after host switch, while those of the rice population increase slightly, indicating that corn is more suitable for improving performance and population growth of C. medinalis than rice, which contradicts with the fact that C. medinalis rarely occurs naturally on corn.

First discovery of Trichogramma oleae (Hymenoptera: Trichogrammatidae) in the wild in China and detection of its endosymbiont Wolbachia
XIAO Zhuang-Ting, WANG De-Sen, HE Yu-Rong
2021, 64(3):  409-418.  doi:10.16380/j.kcxb.2021.03.013
Abstract ( 44 )   PDF (8741KB) ( 35 )   PDF(mobile) (8741KB) ( 7 )     

【Aim】 This study aims to determine the species identity of one Trichogramma species recently collected in the field and to identify the types of Wolbachia in the collected Trichogramma populations in order to find more high quality species resources of Trichogramma. 【Methods】 Two atches of Trichogramma wasps were trapped by hanging up egg cards of the rice moth, Corcyra cephalonica, in the Arboretum of South China Agricultural University. Combined with the morphological identification and the molecular identification method through PCR amplification, sequencing and analysis of ITS2 sequence, the species of Trichogramma materials collected in the field were identified. Wolbachia infection in the Trichogramma wasps was detected by PCR amplification of the outer membrane protein gene (wsp) sequence in Wolbachia. The homology analysis of the detected Wolbachia in the Trichogramma wasps was carried out by PCR amplification of wsp and multilocus sequence typing (MLST). 【Results】 All the two batches of Trichogramma wasps collected in this study were identified as Trichogramma oleae Voegelé & Pointel, in which the infection rate of Wolbachia was 100%. The results showed that Wolbachia in T. oleae belongs to the Sib subgroup in the B supergroup, corresponding to MLST sequence type ST486, having the close relationship with the Wolbachia in T. oleae (former Yugoslavia line), T. pretiosum(Uruguay line) and T.deion (Netherlands line). 【Conclusion】 This is the first record of T. oleae captured in the wild in China, which is a parthenogenetic strain with complete infection of Wolbachia. This study provides a new natural enemy species resource for pest biological control and a valuable research material for further study on the interaction between Wolbachia and Trichogramma.

CONTENTS
Contents of Vol. 64 Issue 3
2021, 64(3):  419-419. 
Abstract ( 29 )   PDF (492KB) ( 27 )   PDF(mobile) (492KB) ( 4 )     
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