Please wait a minute...
  • 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 March 2010, Volume 53 Issue 3
For Selected: View Abstracts Toggle Thumbnails
    Analysis of microsatellite information in EST resource of Nilaparvata lugens (Homoptera: Delphacidae)
    LIU Yu-Di, HOU Mao-Lin
    2010, 53(3):  239-247. 
    Abstract ( 3676 )   PDF (1176KB) ( 982 )     
    Related Articles | Metrics
    Expressed sequence tags (ESTs) are important resources for development of new SSR markers. In this study, 37 398 ESTs of Nilaparvata lugens (Stål) were downloaded from NCBI and analyzed. After the pre-procession, 9 852 non-redundant ESTs with the total length about 7 619 324 kb were obtained. The EST-SSRs were detected under three search qualifications. The search results indicated that the 1-3 repeat motifs were the major repeats among all the SSRs, which accounted for above 95% of all EST-SSRs. A/T was the most frequent motif in the mononucleotide AG/CT and AAG/CTT were the major motifs in the dinucleotide and trinucleotide, respectively. The GC repeat motif was not found in the EST-SSRs of N. lugens. When 100 bp was used as the comparison, the numbers of sequences with both flanking regions ≥100 bp under three search qualifications were 738, 89, and 42, respectively. The analysis of EST-SSRs markers can provide the information for the SSR development of N. lugens and related species. Furthermore, the analysis of the distribution frequency and character of N. lugens EST-SSRs can provide help for the EST-SSRs study of insects.
    Microsatellite DNA polymorphism of the Italian honeybee, Apis mellifera ligustica, in China
    ZHAO Ya-Zhou ,PENG Wen-Jun, AN Jian-Dong, HU Chang-An, GUO Zhan-Bao
    2010, 53(3):  248-256. 
    Abstract ( 4210 )   PDF (1348KB) ( 1363 )     
    Related Articles | Metrics
    To detect the gene flow and gene introgression among different populations, and to evaluate the diversity of Italian honeybee, Apis mellifera ligustica, from different regions in China, the genetic variability of A. m. ligustica was screened in 34 sites from 16 provinces in China where the beekeeping was flourishing with ten polymorphic microsatellite loci. Samples of A. m. carnica from Germany and A. m. ligustica from the USA were genotyped for comparison. The SSR data were analyzed with the software of NTSYS-pc2.1 and popGene32. The results showed that eight of the ten polymorphic microsatellite loci were useful markers to detect the polymorphism of A. m. ligustica. When Nei’s genetic identity index exceeded 0.61, distinct genetic divergence was found in the samples from Zhejiang, Sichuan, Gansu and Yunnan, while other samples still kept unique genetic characteristics typical in the subspecies A.m. ligustica. The samples from northeast of China and Xinjiang region had a close descent relationship with A. m. carnica (the genetic distances between them were all below 0.18149), which might result from the hybridization with A.m. mellifera to some extent. It is so proposed that the characteristics typical of A. m. ligustica and its genetic variability should be protected and the breeding line should be in line with a scientific criterion.
    Molecular cloning and expression profiling of cytochrome P450 monooxygenase gene CYP4CE1 in Nilaparvata lugens (Homoptera: Delphacidae)
    YANG Zhi-Fan, LIU Xiao-Li, ZHANG Yan-Yan
    2010, 53(3):  257-268. 
    Abstract ( 4417 )   PDF (9801KB) ( 1262 )     
    Related Articles | Metrics
    To elucidate the function of P450 genes in Nilaparvata lugens, a novel P450 gene CYP4CE1 was cloned from the 4th instar nymphs of brown planthopper N. lugens by reverse transcription-polymerase chain reaction (RT-PCR), rapid amplification of cDNA ends (RACE) and long-distance polymerase chain reaction (LD-PCR). The full-length cDNA (2 160 bp) of CYP4CE1 has an open reading frame (ORF) of 1 626 nucleotides encoding a protein of 541 amino acids. BLAST similarity searches in GenBank databases with command blastx revealed the deduced protein is most similar to CYP4C39 (GenBank accession no.: JC8026) of the common shore crab (Carcinus maenas) with amino acid identity of 43%, with the second highest-level identity (42%) to CYP4C1 (AAA27819) of the tropical cockroach (Blaberus discoidalis) and CYP4C3 (NP_524598) of Drosophila melanogaster, respectively. Multiple alignment of amino acid sequences revealed that CYP4CE1 is a typical microsomal P450 sharing conserved structural and functional domains with other insect CYP4 members, such as helix K (E--R--P), helix I (AG--T), heme-binding domain (PF--G---C-G--F) and CYP4 specific region (EVDTFMFEGHDTT). Temporal expression analysis indicated CYP4CE1 was induced up to 2.1-fold and kept at a constant level in nymphs exposed to moderately resistant rice Minghui 63 (MH63) seedlings during the time course from 12, 24, 48 to 72 h, compared to the nymphs fed on the susceptible rice Taichung Native 1 (TN1) seedlings. Further spatial gene expression analysis demonstrated that CYP4CE1 was expressed at a high level in fat body and at a low level in integument and gut tissue in nymphs fed on TN1 seedlings. However, after exposure of the nymphs to MH63 seedlings for 24 h, CYP4CE1 was slightly upregulated in integument and fat body (about 1.2-fold, respectively), but dramatically activated up to 12-fold in gut tissue. Whole mount in situ hybridizaion revealed that CYP4CE1 was expressed at a basal level in gut tissue and Malpighian tubules in nymphs fed on TN1 seedlings. After exposure to MH63 seedlings, CYP4CE1 transcripts were significantly accumulated in whole gut tissue including Malpighian tubules. The results suggest a potential role for CYP4CE1 in determining patterns of N. lugens-rice relationships through toxic allelochemical detoxification.
    Structure characteristics and expression profiles of BmGpd, a glycerol-3-phosphate dehydrogenase gene in the silkworm, Bombyx mori
    LU Yan-Jun, JI Ming-Ming, NIU Yan-Shan, ZHANG Sheng-Xiang, SIMA Yang-Hu, XU Shi-Qing
    2010, 53(3):  269-278. 
    Abstract ( 3233 )   PDF (20109KB) ( 1126 )     
    Related Articles | Metrics
    Glycerol-3-phosphate dehydrogenase (GPDH) is a soluble cytosolic NAD-dependent enzyme present in eukaryotic organisms and has some important functions, such as energy transfer. Bombyx mori is a central model animal to research metamorphosis and energy metabolism. In order to determine the role of GPDH in B. mori, we cloned a complete gene of BmGpd based on protein (lethal (2) k05713) sequence of Drosophila melanogaster from NCBI (GenBank accession number: NP_725495.1), which is 27 983 bp in full length and contains 16 exons and 15 introns(GenBank accession number is EF154335). The two complete mRNA transcripts from B. mori strain C108 are 3 456 bp and 2 979 bp in full length (GenBank accession numbers are GQ865685 and GQ865686, respectively), both including a 2 166 bp ORF that encodes 721 amino acids (Mw 82.1 kD, pI 6.43). BmGPD protein includes several membrane-spanning regions and a signal peptide sequence with a length of 20 aa. The results of phylogenetic analysis and motif search revealed that BmGPD belonged to glycerol-3-phosphate dehydrogenase (GPDH) family, which was not reported in B. mori and could be abundantly inducible expression in Escherichia coli. Semi-quantitative RT-PCR analysis indicated that a high-level of BmGpd mRNA occurred in tissues (organs) of the midgut, silk gland, gonad and fat body, and it occurred at the middle stage of the 5th instar larva; however, a low level in the blood, as well as on day 3 of the pupal stage, and a lower level occurred during the diapause. The result of microarray-based gene expression profile showed that the expression abundance of BmGpd was very high in head and integument, while low in fat body and Malpighian tubule on day 3 of the 5th instar larva, and there were no obvious differences between the male and female strains. Expression profile of ESTs indicated that the expression abundance was the highest in the midgut on day 2 of the 4th instar larva. RNAi result suggested that there are strong metabolic compensation pathways to make up for the silence of BmGpd gene. This study provides a basis for further investigating the expression regulation of GPDH and its relationship with metamorphosis and energy metabolism in B. mori.
    Comparison of transcriptional activities of eight promoters and application of hr5-IE1 promoter to realize the expression of EGFP in Bombyx mori BmN cells
    WANG Na, DU Xi-Kuan, JIANG Ming-Xing, ZHANG Chuan-Xi, CHENG Jia-An
    2010, 53(3):  279-285. 
    Abstract ( 4083 )   PDF (1709KB) ( 1404 )     
    Related Articles | Metrics
    In order to find a strong promoter that can be used to promote expression of piggyBac transposase and thereby increase genetic transformation efficiency in cells of the silkworm, Bombyx mori, the transcriptional activities of eight promoters were compared in the BmN cells of B. mori, including hsp70, hsp82, actin3 (A3), polyubiquitin (PUB), α-tubulin, fibroin-L, artificial promoter 3×P3 and immediately early 1 gene promoter flanked by the hr5 enhancer element (hr5-IE1). The results showed that hr5-IE1 displayed the highest transcriptional activity, followed by A3, while the activities of the other six promoters were relatively low. When transfected with an EGFP vector and a piggyBac helper plasmid, in which the expression of piggyBac transposase was driven by hr5-IE1, the EGFP cassette was successfully integrated into the genome of BmN cells. Therefore, hr5-IE1 has the potential of serving as a sound element in future piggyBac-based transgenic research of B. mori with the capability of increasing transformation efficiency.
    Behavioral and EAG responses of Cyrtotrachelus buqueti Guerin-Meneville (Coleoptera: Curculionidae) adults to host volatiles and their body extracts
    YANG Hua, YANG Mao-Fa,YANG Wei, YANG Chun-Ping, ZHU Tian-Hui, HUANG Qiong, ZHAO Xiao-Ying
    2010, 53(3):  286-292. 
    Abstract ( 4131 )   PDF (1225KB) ( 1220 )     
    Related Articles | Metrics
    To find whether there is attraction between the male and female of Cyrtotrachelus buqueti Guerin-Meneville and the influence of the host plant on the behavior of the male and female, Y-tube olfactometer was used to determine the behavioral reaction of adult female and male to the volatiles of their bodies and the host plant after different treatments, and the EAG responses of different portions of antenna of C. buqueti to different combinations of their bodies extracts (female and male) and the volatiles of the host plant. The results showed that the volatiles of the female adult had higher luring activity to the male adult but had repelling action to the female adult, and that of the male adult had certain luring activity to the female adult. The behavioral and electrophysiological responses of female and male adults to the combined odour from their bodies and bamboo shoots were obviously stronger than those to the corresponding volatiles of their bodies only. The EAG response tests showed that the EAG values of different antennal parts to the volatiles from different body parts of C. buqueti adults were obviously different, and the EAG responses of the terminal portion of the antenna to the different combinations of beetle body extracts and the volatiles of the host plant were significantly different (P<0.01). Adults showed the excitement to the extracts of the adult male or female bodies when touched by a glass rod dipped with the extracts, and the excitement rate of female was 6.67%, while that of the male was 26.67%. The results suggest that the pheromones exist in C. buqueti. The pheromones from the female has great allure to the male of the same species and that from the male also has allure to the female of the same species, while the host plant could strengthen the allure between the female and the male.
    Identification and bioassay of aggregation pheromone components of Pissodes punctatus (Coleoptera: Curculionidae)
    ZE Sang-Zi, YAN Zheng-Liang, ZHANG Zhen, MA Hui-Fen
    2010, 53(3):  293-297. 
    Abstract ( 3381 )   PDF (840KB) ( 1055 )     
    Related Articles | Metrics
    For screening attractant semiochemicals of the Armand pine bark weevil, Pissodes punctatus Langor et Zhang, volatiles of adult frass and male hindguts were analysed and tested both in laboratory and in the field. GC-MS analysis confirmed that besides familiar monoterpenes such as α-pinene, β-pinene and 3-carene, cis-2-isopropenyl-1-methylcyclobutannethanol (grandisol) also exists in adult frass and male hindguts of P. punctatus. P. punctatus weevils displayed anemotaxis towards low dosage of 3-(+)-carene, grandisol and its corresponding aldehyde, grandisal, in a Y-tube olfactometer. In field tests, both grandisol and grandisal exhibited attraction activity to the bark weevils. These results suggest that grandisol is a component of aggregation pheromone of P. punctatus.
    Insecticidal activity of extracts from eighteen Chinese traditional herbal plants against Nilaparvata lugens Stål  (Homoptera: Delphacidae) and Spodoptera exigua (Lepidoptera: Noctuidae)
    LI Xiu-Mei, FANG Ji-Chao
    2010, 53(3):  298-306. 
    Abstract ( 3708 )   PDF (1218KB) ( 1160 )     
    Related Articles | Metrics
    In order to screen the environment friendly and highly effective insecticide of plant origin, we determined the contact toxicity of 52 extracts from 18 Chinese traditional herbal plants against the brown planthopper, Nilaparvata lugens Stål, by spray method and their stomach toxicity to Spodoptera exigua. The results showed that all the 52 extracts from the 18 Chinese traditional herbal plants separated with solvents of water, alcohol and petroleum ether had low activity to S. exigua, with the highest corrected mortality of only 33.33%. However, the extracts from Stemona sessilifolia Miq., Phellodendron chinense Schneid, Torreya grandis Fort, Gardenia jasminoides Ellis, Lappula myosotis Moench, and Aucklandia lappa Decne with solvents of alcohol or petroleum ether had high contact activity against the 3rd instar nymphs of N. lugens, with the corrected mortality of ≥80% at 24 h after treatment at 0.8 g/mL, and the LC50 values of their petroleum ether extracts were 0.0826, 0.0455, 0.0145, 0.0047, 0.0038, and 0.0033 g/mL, respectively. The bioassay results of systematic solvent extraction from the extracts showed that the insecticidal components of A. lappa and L. myosotis were predominantly present in the chloroform isolation, suggesting that their insecticidal activity components can dissolve in low-polar solvents. By tracking bioactivity of each fraction of the extract from L myosotis with column chromatography, we found that the Rf limit of the main insecticidal components in the plant was 0.5556-0.5926. This study lays the foundation for purification and confirmation of new insecticidal compounds from plants, including developing their application prospect and detecting novel insecticidal lead compounds.
    Circadian rhythms of sexual behavior and pheromone titers of Holcocerus arenicola (Lepidoptera: Cossidae)
    JING Xiao-Yuan, ZHANG Jin-Tong, LUO You-Qing, LIU Pei-Hua, ZONG Shi-Xiang, LIU Jin-Long, YANG Mei-Hong
    2010, 53(3):  307-313. 
    Abstract ( 4117 )   PDF (988KB) ( 1307 )     
    Related Articles | Metrics
    The calling and mating behavior of Holcocerus arenicola, a primary root-boring pest of sand Salix (Salix psammophila) were observed during the 6 h of the scotophase to investigate their activity rhythm. The pheromone titer was analyzed by the electroantennogram (EAG) and gas chromatograph (GC) to determine the diel periodicity of pheromone production during one scotophase and the effect of female age on pheromone production. The results showed that most females initiated calling during the 0.5-1 h after lights off, and the maximum calling occurred during the 2nd night after emergence. The mating was observed during the 1-2 h of the dark phase, and the mating percentage of 1-d-old females was the highest. Mating lasted for an average of 24.16±2.64 min and occurred earlier as females got older. The sexual activity of 5- to 6-d-old females was rarely observed in the test. The synthesis of pheromone started 1-2 h prior to the onset of calling and reached a peak during the first 2 h of the scotophase. The pheromone titer during the calling period decreased significantly with age, being highest in extracts from newly emerged females. Field trial showed that traps baited either with virgin females or female sex gland extracts could effectively capture males. These results suggest that there was a synchronous relationship between the pheromone titer and the sexual activity, and also a potential use of long-range sex pheromone for the control of H. arenicola.
    Temporal effect of tobacco defense responses to Myzus persicae (Sulzer) (Homoptera: Aphididae) induced by Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) B biotype
    WANG Cheng-Xiang, XUE Ming, BI Ming-Juan, LI Qing-Liang, HU Hai-Yan
    2010, 53(3):  314-322. 
    Abstract ( 4026 )   PDF (1516KB) ( 991 )     
    Related Articles | Metrics
    To determine the defense responses of tobacco plants to Myzus persicae induced by Bemisia tabaci B biotype and their temporal effect and explore their role in interspecific competition between B. tabaci and M. persicae, we investigated the effect of tobacco defense responses induced by B. tabaci on the development of M. persicae with the method of clip-cage. Moreover, the changes of major nutritional indices in tobacco plants preinfested by B. tabaci were also studied using biochemical analysis. The results showed that B. tabaci B biotype could induce the defense responses of tobacco plants to M. persicae distinctly.  These responses inhibited the survival and development of M. persicae significantly and had distinct temporal effects.  The mortalities of M. persicae fed on systemic white-vein leaves preinfested by B. tabaci nymphs for 5 d were 36.13% higher than those on the control leaves. After infestation by B. tabaci nymphs for 10 d, the mortalities of M. persicae were 72.78% higher than those on the control leaves, and the average relative growth rates were reduced significantly compared with the control. After infestation by B. tabaci nymphs for 15 d, the mortalities were still 58.89% higher than those on the control plants. On the 10th day of the infestation by B. tabaci nymphs, B. tabaci nymphs fed on treated plants were wiped off, and then the 1st nymphs of M. persicae were placed on the white-vein leaves. After that, they were clip-caged immediately.  Significant differences in the mortalities and relative growth rates of M. persicae were found between the systemic white-vein leaves of control plants and the leaves of treated plants within 15 days after removing B. tabaci nymphs(P<0.05). But the differences were no longer found on the 20th day after removing B. tabaci nymphs. The results suggest that the defense responses of the systemic white-vein leaves of tobacco plants induced by B. tabaci should continue being expressed for about 15 d. The damaged leaves preinfested by B. tabaci have no significant negative influence on the mortalities and relative growth rates of M. persicae compared with the control leaves.  Both soluble sugar and soluble protein contents are reduced in the systemic white-vein leaves preinfested by B. tabcai B biotype, which have distinct negative correlation with the mortalities of M. persicae.
    SCAR marker for rapid identification of the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)
    MENG Xiang-Qin, MIN Liang, WAN Fang-Hao, ZHOU Zhong-Shi, WANG Wen-Kai, ZHANG Gui-Fen
    2010, 53(3):  323-330. 
    Abstract ( 3606 )   PDF (3422KB) ( 1249 )     
    Related Articles | Metrics
    The western flower thirps, Frankliniella occidentalis (Pergande), is a worldwide pest, causing serious damage to a wide range of host plants. It was first reported in China in 2003, with a trend of further spreading. Most of thrips species are small in size and similar in morphology, which makes them hard to be distinguished quickly. In the present research, a pair of SCAR (sequence characterized amplified regions) primers (FOMF/FOMR) which are specific to western flower thrips was developed by using other nine familiar thrips species as the control. The fragment amplified by the primers FOMF/FOMR was 320 bp in length. Specificity tests performed with this pair of primers showed that all F. occidentalis specimens were detected positively and no cross reactions with other 41 thrips species, including F. intonsa (Trybom), F. tenuicornis (Uzel) and Thrips tabaci L., were detected. The method was tested on single male and female adult, single pre-pupa and pupa, single 1st- and 2nd-instar larva, and even single egg, and proved to be applicable for these stages of F. occidentalis. Moreover, the 320 bp genomic DNA fragment was clearly identified in the host plant tissues collected in F. occidentalis infested areas. When the dilution was 1/160 of a whole female adult of F. occidentalis, the 320 bp DNA fragment could be identified for all replicates. The technique should be useful in quarantine at ports and in pest detection and monitoring during transportation of flowers, vegetables and seedlings.
    A revision of the genus Formosatettixoides Zheng (Orthoptera: Tetrigidae), with description of one new species from China
    ZHENG Zhe-Min, ZENG Hui-Hua
    2010, 53(3):  331-334. 
    Abstract ( 3575 )   PDF (503KB) ( 1137 )     
    Related Articles | Metrics
    The paper describes 7 species of the genus Formosatettixoides Zheng from China, Nepal and North Korea, including one new species from Xizang, China: Formosatettixoides motuoensis sp. Nov. A key to all species of the genus including their distribution records provided. The specimens of new species are kept in the Institute of Zoology, Shaanxi Normal University.
    Pleiotropic functions of insect vitellogenin:With honey bee Apis mellifera as an example
    YAN Ying, PENG Lu, WAN Fang-Hao
    2010, 53(3):  335-348. 
    Abstract ( 4189 )   PDF (2353KB) ( 1164 )     
    Related Articles | Metrics
    Vitellogenin is the key factor in vitellogenesis in insects. As RNA interference was applied, pleiotropic functions of vitellogenin in honey bee Apis mellifera were discovered, including climate adaption, ovary activation, reproductive competition, labor differentiation, behavior formation, life extension and food conversion. Thus, A. mellifera vitellogenin was also called “pleiotropic protein”. Many theories such as “double repressor hypothesis”, “feedback loop mechanism” and “vitellogenin-to-jelly mechanism” were proposed to explain the function and regulation of vitellogenin. All these studies suggested that this protein has been upgraded from a downstream factor in female reproductive physiology to a major life cycle regulator in the highly eusocial honeybees. Studies on vitellogenin in honey bee not only promoted the research in insect sociobiology considerably, but also provided a new aspect to study the insects with complex reproductive behavior. Here research progress in pleiotropic functions of insect vitellogenin is reviewed with A. mellifera as an example, including its physicochemical properties, molecular evolution, occurrence, regulation, pleiotropic effects and research methods.
    Control potential of extracts of Mikania micrantha on Brontispa longissima (Coleoptera: Chrysomelidae)
    LV Chao-Jun, ZHONG Bao-Zhu, SUN Xiao-Dong, QIN Wei-Quan, PENG Zheng-Qiang
    2010, 53(3):  349-353. 
    Abstract ( 3044 )   PDF (770KB) ( 1055 )     
    Related Articles | Metrics
    To assess the potential of Mikania micrantha on IPM and provide reference for Brontispa longissima management, the bioactivities and field control effect of extracts of M. micrantha on the coconut leaf beetles were investigated. The results indicated that the extraction rates of methyl alcohol, ethyl acetate, hexane, petroleum ether, chloroform, distilled water and ethanol were 10.54%, 7.17%, 6.22%, 6.28%, 8.67%, 8.62%, 10.36%, respectively. Methyl alcohol and ethanol showed the highest extraction ability among different solvents. The methyl alcohol and ethanol extracts of M. micrantha showed activities to the coconut leaf beetles, and the activity of the ethanol extract was better than that of the methyl alcohol extract. The LC50 of the ethanol extract to 1st to 5th larvae and adults of coconut leaf beetles were 7.09, 7.88, 8.93, 11.88, 13.26 and 17.46 mg/g, while the LC50 values of the methyl alcohol extract were 12.36, 14.85, 15.89, 17.46, 19.91 and 27.81 mg/g, respectively. Both extracts delayed the eclosion of the coconut leaf beetles and induced the deformity of adults. Meanwhile, the time of egg incubation was also delayed, and the bioactivity of the ethanol extract was obviously higher than that of the methyl alcohol extract. The field trial results indicated that the ethanol extract of M. micrantha had great activities to the coconut leaf beetles and the control effects were all above 80% in the 100 mg/mL and 20 mg/mL treatment after 7 d. It is so concluded that the extracts of M. micrantha have good bioactivity and control potential on the coconut leaf beetles.
    Recognition responses of apterous Myzus persicae to the visual and olfactory cues from Propylaea japonica adults
    LI Wei-Zheng, FU Guo-Xu, CHAI Xiao-Le, WANG Ying-Hui, ZHANG Yuan-Chen, YUAN Guo-Hui
    2010, 53(3):  354-359. 
    Abstract ( 3495 )   PDF (1224KB) ( 1280 )     
    Related Articles | Metrics
    In order to investigate whether Myzus persicae can recognize the visual and olfactory cues from its predators, bioassays were made on the recognition responses of apterous M. persicae to elytra color and volatiles of Propylaea japonica adults in the laboratory by using the prey-predator system of M. persicae. P. japonica. The results of choice response bioassay showed that apterous M. persicae could detect the presence of P. japonica both through visual sense and olfactory sense, suggesting that there is a certain redundancy in the recognition of visual and olfactory cues. The results of dose-response bioassay showed that there was a positive linear relationship between the dose of the ladybird extract and the repellent percentage of the aphids. The critical dose for recognition was within the range of 0.3-0.6 ladybird equivalent, and the repellence of 1.2-1.5 ladybird equivalent was equal to that of 20 live P. japonica adults. We thus conclude that the aphids have the ability to detect the presence of P. japonica and adopt initiative avoidance responses to reduce the predation risk.