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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
Table of Content
20 September 2013, Volume 56 Issue 9
For Selected: View Abstracts Toggle Thumbnails
    Cloning and expression profiling of genes involved in glycometabolism in the midgut of Spodoptera litura (Lepidoptera: Noctuidae)
    LUO Wan-Bing, HE Wen-Jing, HUANG Yu-Qiu, HU Dan, HUANG Li-Hua, FENG Qi-Li
    2013, 56(9):  965-973. 
    Abstract ( 3499 )   PDF (3146KB) ( 1363 )     
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    The common cutworm, Spodoptera litura is an important agricultural pest, which has spread out worldwide. It undergoes larval-pupal metamorphosis in the life cycle. As a major organ for food digestion and nutrient absorption, the midgut is degraded and reconstructed during the metamorphosis to adapt to the dramatic change in food type between larvae and adults. Therefore, the substances and energy metabolism in the midgut change accordingly. In order to study the sugar metabolic dynamics in the midgut during metamorphosis, twelve glycometabolism-related genes were identified from the midgut EST library of S. litura. Three of them were cloned to obtain their full cDNAs. The mRNA expression profiles of all the 12 genes were examined by realtime or semi-quantitative PCR in the midgut during metamorphosis, and their mRNA levels in response to the induction of hormones and starvation were also quantified. The results indicated that the open reading frames of α-L-fucoside fucohydrolase, N-acetylglucosamine-6-phosphate deacetylase and enolase genes are 1 461, 1 200 and 1 299 bp, and the predicted proteins are 56.3, 43.3 and 46.7 kDa, respectively. The mRNA expression profiles revealed five different patterns: (Ⅰ) High expression only in the larval stages, including salivary maltase precursor, glycosyl hydrolase family 31 protein, mitochondrial aldehyde dehydrogenase and β-1, 3-glucanase genes. (Ⅱ) High expression only in the prepupal stage, including β-glucuronidase and β-N-acetylglucosaminidase 3 genes. (Ⅲ) High expression only in the pupal stage, including glucosamine-6-phosphate isomerase gene. (Ⅳ) High expression both in the prepual and pupal stages, including glucosidase, α-amylase, N-acetylglucosamine-6-phosphate deacetylase and α-L-fucoside fucohydrolase genes. (Ⅴ) Stable expression, including enolase gene. This indicates that significant changes happen in glycometabolism in the midgut during metamorphosis. Juvenile hormone (JH) had no obvious effect on the mRNA level of these genes. However, 20-hydroxyecdysone (20E) suppressed the mRNA level of type I gene such as glycosyl hydrolase family 31 protein gene, and up-regulated the type Ⅲ gene (glucosamine-6-phosphate isomerase gene). In addition, the mRNA level of all the genes was significantly suppressed by starvation. The results suggest that the dynamics of mRNA level of sugar metabolic genes may be controlled by both 20E and starvation-related factor. These findings in glycometabolism will contribute to elucidating the mechanism of larval-pupal metamorphosis.
    Cloning and expression analysis of a gene encoding phospholipase A2 from the venom of Bombus hypocrita (Hymenoptera: Apidae)
    GAO Li-Jiao, HUANG Jia-Xing, WU Jie
    2013, 56(9):  974-981. 
    Abstract ( 2597 )   PDF (4973KB) ( 1737 )     
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    Phospholipase A2 (PLA2) is the major component of bee venom as well as the main allergen of venom, and plays a key role in the individual and colony defense of bumblebee. A PLA2 gene from Bombus hypocrita was cloned, identified and expressed in this study in order to clear its characteristics and function. The results indicated that the full-length cDNA of B. hypocrita PLA2 gene is 2 272 bp in length, consisting of 4 extrons and 3 introns. The coding region, 543 bp in length, encodes a 180-amino-acid protein. Comparative analysis revealed that the mature PLA2 (consisting of 136 amino acids) possesses features consistent with PLA2s from other bees, including ten conserved cysteine residues, a highly conserved Ca2+-binding site and one active site. Phylogenetic tree of PLA2 sequences showed that Bombus PLA2 clustered into a branch independent with Apis PLA2 which differentiated earlier. The real-time PCR analysis showed that B. hypocrita PLA2 was expressed in different day-old adults, and the expression level increased first and then decreased, with the maximum expression level in the 10 day-old adults. The PLA2 gene were highly expressed in the venom gland, ovary and midgut, less expressed in legs, antennae and esophageal glands, and not expressed in fat body, muscles, nerve, tracheae, compound eyes and brain. This study revealed the characteristics and expression of PLA2 gene in B. hypocrita, which is useful not only for further studies on the function and mechanism of Bombus PLA2, but also for the development of new reagent of bee venom.
    Activity changes of four enzymes in naturally overwintering adults of Chrysoperla sinica (Neuroptera: Chrysopidae) during the process of diapause termination under long and short photoperiods
    CHEN Zhen-Zhen, SONG Nuan, GUO Ya-Nan, YU Jin-Feng, YIN Xiang-Chu, ZHANG Fan, XU Yong-Yu
    2013, 56(9):  982-988. 
    Abstract ( 2130 )   PDF (4737KB) ( 1078 )     
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    Photoperiodic cues play important roles in insect environmental adaption, and insects can regulate their physiological processes to adapt environmental changes through perceiving the changes of photoperiod. In order to investigate the mechanisms of physiological adaptation to photoperiod changes, we detected the activities of catalase (CAT), superoxide dismutase (SOD), Na+K+-ATPase and lactic dehydrogenase (LDH) of overwintering adults of Chrysoperla sinica (Tjeder) in the progress of diapause termination under the long (15L∶9D) and short photoperiods (9L∶15D) in the laboratory conditions. The CAT activity of both female and male adults reached a peak at 5 d after treatment and was higher under the long photoperiod than under the short photoperiod, with significant difference at 15 d (P<0.05) and 20 d after treatment (P<0.005). However, the CAT activity was significantly lower under the long photoperiod than under the short photoperiod at 10 d after treatment (P=0.005). The SOD activity of female adults was significantly lower under the long photoperiod than under the short photoperiod at 5 d after treatment (P<0.001). The SOD activity of male adults under the long photoperiod was significantly higher at 5 d (P=0.04), 15 d (P<0.001) and 20 d after treatment (P=0.003) than that under the short photoperiod. The LDH activity decreased with the time under the two photoperiods, and the activities in both treatments were significantly lower than that in adults treated for 0 d (P<0.001). The results indicated that the differences of enzyme activities of Ch. sinica under the long and short photoperiods may be the main physiological factor triggering the content of bio-chemical substances in the adult body and reproductive status during the adult diapause termination.
    Morphology of seminal vesicle and sperm of the male Polistes chinensis antennalis (Hymenoptera: Vespidae)
    TAN JiangLi1,*, LI JunLin1, XING LianXi1, CHEN XueXin2
    2013, 56(9):  989-995. 
    Abstract ( 2820 )   PDF (12850KB) ( 1343 )     
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    Morphological diversity of seminal vesicles and spermatozoa play an important role in the taxonomic and phylogenetic analysis, but it has been scarcely studied in the subfamily Polistinae, even in the whole Vespidae. The male reproductive system of the paper wasp Polistes chinensis antennalis Pérez was dissected for the first time, with emphasis on the ultrastructure of the seminal vesicle. The morphology of the sperm was also briefly reported. Seminal vesicle and accessory gland are not surrounded by a common sheath. The epithelium of seminal vesicle consists of a monolayer of cubical cells, adhering to a thick basal lamina, and these epithelial cells are polarized: the apical half of the epithelial cells is especially rich in mitochondria with the apical membrane being differentiated into microvilli, while the basal half contains the usual cellular organelles, including some mitochondria, the nucleus and prominent inclusions. The spermatozoa of P. chinensis antennalis are about 94 μm in length with the head about 21.4 μm in length, so it is the species with the shortest sperm and the longest relative head length of sperm described for the family Vespidae. The results may provide a theoretical foundation for  phylogenetic analysis and reproductive physiology of Vespidae.
    Effects of photoperiod and temperature on diapause induction in Ostrinia furnacalis
    GUO Jian-Qing, ZHANG Hong-Gang, WANG Zhen-Ying, HE Kang-Lai
    2013, 56(9):  996-1003. 
    Abstract ( 3032 )   PDF (1175KB) ( 1073 )     
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    The Asian corn borer, Ostrinia furnacalis (Guenée), exhibits a facultative diapause. Its diapause characteristics play a pivotal role not only in allowing its populations to use the most favorable climatic conditions to the greatest extent, but also in regulating its seasonal population dynamics. The objective of this study is to understand the effects of seasonal cues such as photoperiod and temperature on diapause induction in O. furnacalis, which will provide the scientific evidence for forecasting population dynamics. Effects of photoperiod and temperature on larval diapause were examined under 80% relative humidity and combinations of temperatures 20℃, 27℃ and 30℃ with 11 photoperiods in the environmental chambers (HPS-500 and HPG-320H) with four geographic populations, i.e., Nong’an population (NA) of Jilin Province, Hengshui population (HS) of Hebei Province, Huizhou population (HZ) of Guangdong Province, and Haikou population (HK) of Hainan Province. The results indicated that photoperiod played a key role in diapause induction. Short-day caused larval diapause at 20℃, and the photoperiod response under a series of diel patterns showed that it was a typical long-day insect. The critical day-lengths were 14 h 3 min, 13 h 59 min, 13 h 32 min, and 13 h 7 min for NA, HS, HZ, and HK populations, respectively, which were declined from the north towards the south. The day-length of 12 h induced the highest diapause rate. The sensitivity of larvae in response to the photoperiod for induction of diapause declined with the increase of latitude. However, the photoperiod curve showed that it was a shortday and longday insect at 27℃. There were two critical day-lengths for NA, HS, HZ, and HK populations, i.e., 12 h 50 min and 13 h 32 min, 11 h 35 min and 13 h 8 min, 12 h 58 min and 13 h 1 min, and 11 h 50 min and 12 h 26 min, respectively. The highest diapause rate for each population was significantly lower at 27℃ than that at 20℃. The critical day-length would be shortened when the temperate increased from 20 to 27℃. However, the diapause rate was less than 4.3% at 30℃, suggesting that the diapause was almost inhibited completely. These results demonstrated the compensatory effect of temperature on diapause induction by photoperiod in O. furnacalis. In conclusion, O. furnacalis has a temperature-dependent type I photoperiod diapause response in the nature; the critical day-length of the population increases with its geographical location toward the north; and the population diapause response is also characterized as a short day-long day insect, which may play a key role in the presence of multi-populations with diverse ecotypes of voltinism in one geographic location.
    Effects of temperature on the development and reproduction of Chrysolina aeruginosa
    WEI Shu-Hua, ZHU Meng-Meng, ZHANG Rong, HUANG Wen-Guang, YU Zhao
    2013, 56(9):  1004-1009. 
    Abstract ( 2641 )   PDF (944KB) ( 819 )     
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    To illustrate the influences of temperature on the development and reproduction of Chrysolina aeruginosa Faldermann, the development and fecundity of C. aeruginosa at five temperatures (13, 18, 23, 28 and 33℃) were investigated, with Artemisia sphaerocephala served as food. The results showed that temperature had significant effects on the developmental duration, survival rate and reproduction of C. aeruginosa. The developmental duration of every stage reduced with increasing temperatures from 13 to 28℃, and there was a positive relationship between developmental rate and temperature. Further increase of temperature to 33℃, however, was unfavorable to its larval and pupal development. The larval duration at 33℃ was significantly longer (P<0.05) than that at 18℃, 23℃ and 28℃, and the adult could not emerge from soil. Low temperature affected the survival rate of eggs while high temperature affected the pupal survival rate, suggesting that excessively low or high temperature was unfavorable to its survival. The oviposition amount of C. aeruginosa at different temperatures was significantly different (P<0.01) and varied in the order of 28℃>23℃>18℃>13℃. Based on the direct optimal method, the developmental threshold temperatures for egg, 1st to 3rd instar larva, and 4th instar larva plus pupa were 9.72, 7.11, and 8.77℃, respectively, and the corresponding effective accumulated temperatures were 115.36, 441.91, and 448.40 degree-days, respectively. The results provide the basis for forecasting the occurrence of C. aeruginosa and are applicable in agricultural practices.
    Optimal day-age and temperature for cold storage of Trichogramma chilonis (Hymenoptera: Trichogrammatidae) reared on Corcyra cephalonica (Lepidoptera: Galleriidae) eggs
    YUAN Xi, FENG Xin-Xia, LI Dun-Song, ZHANG Bao-Xin, WANG Zhen-Ying
    2013, 56(9):  1010-1019. 
    Abstract ( 3665 )   PDF (1524KB) ( 966 )     
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    In order to comprehensively evaluate the impacts of cold storage on Trichogramma reared  on Corcyra cephalonica eggs, the effects of cold storage on pupal survival rates, adult emergence rates and adult deformity rates of Trichogramma chilonis were investigated through applying storage temperature (3℃ and 10℃), day-age (age from 1 to 10 days after parasitization of wasp on host egg, respectively) and period (1, 2, 3 and 4 weeks) as the experimental factors and taking C. cephalonica eggs as the host. The results indicated that those three factors substantially influenced the pupal survival rates, adult emergence rates and adult deformity rates separately or interactively (P<0.05). Among all storage temperatures tested, T. chilonis was most susceptive to 3℃, its pupal survival rate for the age of 1-3-day-old and adult emergence rate for all ages decreased notably at this temperature (P<0.05), and therefore 3℃ was considered to be unfavorable for long-term storage. At 10℃, pupal survival rates for all ages and adult emergence rates for the age of 1-3-day-old were not affected by the storage period, and the adult emergence rate was still over 74% after cold storage of 4 weeks, thus 10℃ was considered to be more favorable for storage than 3℃. The favorable age for cold storage varied with different storage temperatures. At 10℃, which was favorable for cold storage, the most favorable age was for 3dayold while there was no distinct difference from the control groups in pupal survival rates (74.09%-77.59%) and adult emergence rates (74.26%-90.37%) in different periods, but they were notably higher at this age than those in other ages. After the cold storage under 10℃ for 1-3 weeks, the adult deformity rates were within 27%. The results suggest that the favorable age for cold storage of T. chilonis reared on C. cephalonica eggs varies with different cold storage temperatures.
    Identification and damage of the bluegrass webworm moth, Parapediasia teterrella (Zincken) (Lepidoptera: Crambidae), a new invasive pest on lawns in Shanghai, Eastern China
    GAO Lei, JU Rui-Ting, DING Jun-Jie, XU Ying, WANG Jian-Guo
    2013, 56(9):  1020-1025. 
    Abstract ( 3935 )   PDF (15059KB) ( 1138 )     
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    An invasive insect species on turfgrasses (Cynodon dactylon) in lawns is newly recorded in Shanghai, Eastern China. In the current investigations, we determined the taxonomic status, host plants and damages caused by this species. The species was identified based on morphological comparison, and then confirmed by the sequencing and comparison of mitochondrial cytochrome oxidase I (COI) gene. Both morphological and molecular  identification indicated that the newly invaded species is the bluegrass webworm moth, Parapediasia teterrella, a moth native to North America. Field investigation showed that the species was widely distributed in Shanghai and caused serious damages to turfgrasses, especially C. dactylon. In some parks, the maximum population density of this pest reached to 740 individuals/m2. It is believed that this insect species should be listed as a new invasive pest in China due to its exotic and established characteristics as well as serious economic effects in the new regions. Therefore, it is urgently necessary to focus on the integrated management of newly introduced P. teterrella in order to reduce its threat to turfgrasses and gardening landscapes in China.
    Research progress in microRNAs in insects
    LIU Yong-Ping, YANG Jing, LIU Yun
    2013, 56(9):  1026-1037. 
    Abstract ( 2906 )   PDF (1913KB) ( 1598 )     
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    MicroRNAs (miRNAs), a class of short (21-24 nt) non-coding single-stranded RNA molecules, are encoded by endogenous genes found in the 1990s. They play critical roles in gene expression and regulation through translational inhibition or mRNA degradation in eukaryotes. In this article, we briefly summarized miRNA biogenesis and its regulation mechanism, and reviewed the recent progress in identification of insect miRNAs, their target gene predication and function verification, sequence characteristics and evolution, their biological functions on Drosophila and non-drosphilid insects, available network platform and so on, to provide references for further research. Researches on insect miRNAs showed that they are involved in almost every biological process including cell differentiation, cell proliferation, cell apoptosis, embryogenesis, organogenesis, morphogenesis, physiological metabolism, environmental coordination, cognitive behavior and immune defense. So, the indepth study of their biological functions, regulation and application would become the important aspects in the future.
    Research progress in trail pheromones in termites
    JI Bao-Zhong, LIU Shu-Wen, CAO Dan-Dan, YANG Jin-Jin, ZHAO Zheng-Ping, ZHANG Xin-Wei
    2013, 56(9):  1038-1046. 
    Abstract ( 2848 )   PDF (3776KB) ( 1131 )     
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    In recent years, the use of solid phase microextraction has promoted significant advances in the field of trail pheromones of termites. Up to now, trail pheromones of termites are known in 77 species, and the common components include dodecaenol, dodecadienol, dodecatrienol as well as neocembrene. The trail pheromones in termites mainly consist of single or two components. In termites, trail pheromones emanate from the sternal gland. Mastotermes darwiniensis belonging to Mastotermitidae is the only extant termite to possess three sternal glands. Other termites possess one sternal gland located on the 4th or 5th sternite. All sternal glands possess class Ⅰ and Ⅱ cells. Class Ⅲ cells are present only in the Termopsinae, Serritermitidae and Rhinotermitidae. No studies have been done on the biosynthesis of termite trail pheromones. Three biosynthesis pathways were hypothesized: the mevalonate pathway, the aliphatic alcohol pathway and the saturated cuticular hydrocarbon pathway. The parsimony of trail pheromones is well developed in termites. The same or closely related trail pheromones are present in species from different geographic origins, different ecological life types, and unrelated taxa. In many species, the same semiochemical possesses the double function of trail pheromone and sex-pairing pheromone. The adaptability and evolutionary mechanism of both the species specialty and the parsimony of the trail pheromones need to be further explored.
    In-nest ethology and mating strategies of the carpenter bees Xylocopa spp. (Hymenoptera: Apidae)
    HE Chun-Ling , NIU Ze-Qing, LUO A-Rong, ZHU Chao-Dong, WU Yan-Ru
    2013, 56(9):  1047-1054. 
    Abstract ( 2850 )   PDF (1409KB) ( 1220 )     
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     Large carpenter bees (the genus Xylocopa), as an important group of bees (Apidae), play an important role in studying early stages of insect social evolution. This article reviewed the research progress on nesting habits, social behaviors, and mating strategies of Xylocopa. Investigations in recent years showed that nest architecture is linked to numerous life history elements including the distribution of nesting events such as constructing cells and laying brood, brood size, provisioning efficiency, and susceptibility to parasitism. Competition among conspecific females at nesting sites increases as the population becomes larger, which is reflected by more intensive guarding of nests, especially during the late spring and summer. Nest guarding is not only against conspecific females but also against other species. This insect group presents the evolution tendency from solitary to eusociality, and exhibits subsocial, communal, semisocial and eusocial forms. Xylocopa is found to be socially polymorphic with both solitary and metasocial or semisocial nests in the same population. As for mating strategies, males of carpenter bees display certain morphological characters, which are useful to attract females for mating, and also have complex territorial behavior. These findings are not only important for us to understand behavioral biology of carpenter bees, but also helpful for further exploration in the evolution process of social bees.
    Higher level phylogeny of Coleoptera based on molecular methods: current status and problems
    NIE Rui-E, YANG Xing-Ke
    2013, 56(9):  1055-1062. 
    Abstract ( 3182 )   PDF (1407KB) ( 1815 )     
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    Coleoptera is the most diverse among all organismal lineages, which is subdivided into four suborders, i. e., Archostemata (Kolbe, 1908), Myxophaga (Crowson, 1955), Adephaga (Schellenberg, 1806) and Polyphaga (Emery, 1886). With the popularity of molecular biology, the research of molecular phylogeny of Coleoptera has been improved a lot. In this article, the progress and problems in the research of higher level molecular phylogeny of Coleoptera were reviewed. Based on molecular methods, many hypotheses were proposed. Most of them supported that the four suborders are all monophyletic, while their relationship is still unclear. The molecular phylogenetic relationship of superfamilies or families of each suborder also got much understanding. For example, molecular results supported that Adephaga could be divided into two groups, i. e., Hydraphaga and Geadephaga, which were sister groups, indicating a single colonization of the aquatic medium. Currently, the higher level phylogenetic studies of Coleoptera based on molecular methods are not mature and perfect, and this is mainly manifested in limited material selection, uneven number and unsatisfactory fitness of genes, and lack of researches of some key nodes.
    Cloning and bioinformatical analysis of vitellogenin gene of the Indian malaria vector Anopheles culicifacies (Diptera: Culicidae)
    Monika MIGLANI, Surendra Kumar GAKHAR
    2013, 56(9):  1063-1074. 
    Abstract ( 2550 )   PDF (17449KB) ( 3087 )     
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     Vitellogenin (Vg) is the major yolk protein precursor which is synthesized abundantly in the insect fat body after the female ingests blood meal. The regulatory elements of vitellogenin have been used to drive the tissue specific expression of anti parasitic gene in mosquitoes, where its maximum interaction could take place with the parasite. However, no endogenous promoter has been analysed so far in the Indian malaria vector Anopheles culicifacies which is responsible for 60%-70% of malaria cases in India. In this study, the vitellogenin gene including 5′ upstream regulatory region of Anopheles culicifacies was cloned after PCR amplification and named AncuVg (GenBank accession number JN113091). It contains an ORF of approximately 6.2 kb encoding 2 052 amino acids with a putative signal peptide of 16 residues. It also contains an N_Vitellogenin region and a VWF type D domain, that are found conserved in other insect Vgs too. The molecular weight of the predicted polypeptide is 238.0 kDa. It possesses four consensus (RXXR/S) cleavage sites and close to the C-terminus there is a GL/ICG motif followed by nine cysteine residues and a DGXR motif, located 18 residues upstream from the GL/ICCG motif. Three polyserine regions were found in the deduced amino acid sequence: two in the amino terminal region and one in the carboxy terminal region. The extent of codon bias in mosquito vitellogenin genes based on the relative synonymous codon usage values were determined by the effective number of codons. The 3D structure of A. culicifacies Vg was also predicted. The 5′ upstream region of the AncuVg gene was analyzed to understand the regulation of Vg gene transcription. Phylogenetic analysis using the 5′ upstream region of Vg genes showed their conformation to three major clades among mosquitoes. Homology and other characteristic features of Vg have also been analyzed using various bioinformatic tools.
    Diversity analysis of bacterial community in midguts of larvae of the striped stem borer, Chilo suppressalis (Lepidoptera: Crambidae), with different levels of resistance to insecticides
    ZHANG Jue-Feng, HE Yue-Ping, CHEN Jian-Ming
    2013, 56(9):  1075-1082. 
    Abstract ( 2644 )   PDF (2964KB) ( 1238 )     
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    Bacterial community in midguts of larvae of four populations of the striped stem borer, Chilo suppressalis, with different levels of resistance to insecticides was detected and analyzed using PCR-DGGE and 16S rDNA libraries. The bioassay showed that compared to the susceptible strain, the Heilongjiang population (HLJ population), the Lianyungang population (LYG population) had low to middle resistance level to monosultap, chlorpyrifos and triazophos, the Rui’an population (RA population) and Zhuji population (ZJ population) had middle to very high resistance level to the above three insecticides, and the latter three populations all were susceptible to avermectins. DNA sequence analysis indicated that the PCR-amplified 16S rDNA genes represented 21 bacteria phylotypes, and most of them belonged to the genus Streptococcus. Bacterial community in larval midgut of four different resistant populations was mainly the genus Enterococcus, except that the dominant bacteria in ZJ population were Lactococcus garvieae, L. lactissubsplactis and Ochrobactrum anthropic. The DGGE profiles demonstrated that the bands of HLJ population were simple, those of LYG population were the most abundant, and the band richness of ZJ population was similar to that of RA population. The common bacteria in the four populations were Enterococcus faecium, E. hirae and Arthrobacter sp., and the main bacteria were the genus Enterococcus. The results suggest that there is difference in bacterial abundance in larval midgut of C. suppressalis with different levels of resistance to insecticides, which may be related to the difference of resistance to insecticides among different populations of C. suppressalis.
    Mathematical model of the egg mass of Eucriotettix grandis and its ecological implications
    BAI Ke-Qiang, CAO Cheng-Quan, SONG Wei
    2013, 56(9):  1083-1087. 
    Abstract ( 2032 )   PDF (8806KB) ( 1161 )     
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    【Aim】 To explore the ecological implications of the unique merogony morphology of Eucriotettix grandis. 【Methods】 Based on a large number of field investigations on the ecological characteristics of egg mass of E. grandis, we got the fitted equation of merogony cross section curve through extracting section line in the three dimensional data point from the photos of egg mass of E. grandis, built the corresponding mathematic model by means of line fitting process, and analyzed the geometrical features of data fitted curve from the aspects of fitted curve curvature and second derivative value map. 【Results】 E. grandis often lays intact egg mass which is near-hexagonal orange segment, with an obvious hemispheric groove on the top and a slightly apophysis in the middle part of the bottom. By using line fitting theory, the kernel function with both the goodness of fit and the smoothness was constructed, and the model curve obtained from the function value fitted quite well with the curve of true value. 【Conclusion】 The groove is probably for water preservation to keep the egg mass moist and make the egg more likely to survive and incubate. The edges and corners are conducive to relieve the long distance rolling and breaking for egg mass, and the tight coupling of egg mass is beneficial to moisturizing the egg.
    Ultrastructure of antennal sensilla in three species of Frankliniella Karny (Thysanoptera: Thripidae)
    LI Wei-Na, FENG Ji-Nian
    2013, 56(9):  1088-1100. 
    Abstract ( 3064 )   PDF (9954KB) ( 1296 )     
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     The type, number, distribution and ultra-morphology of antennal sensilla of both genders in three Frankliniella thrips, i. e., Frankliniella intonsa (Trybom), F. tenuicornis (Uzel) and F. occidentalis (Pergande), which are serious agricultural pests in China, were observed and compared using scanning electron microscopy. Through the morphological observation and comparison, we hope to clarify the differences of sensilla among these species, supplement the detail information of thrips sensilla and perfect the researches on thrips morphology. The results showed that there are eight types of sensilla on the antenna of every species, i. e., Böhm bristles, sensilla campaniformia, sensilla trichodea, sensilla chaetica, sensilla basiconica, sensilla coeloconica, sensilla cavity and unusual sensillum. The number and distribution of sensilla are uneven on each antennal segment. The analysis results revealed that every type of sensilla has a relatively stable distribution pattern, and there is no significant difference among closely-related species or between sexes.