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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 October 2003, Volume 46 Issue 5
For Selected: View Abstracts Toggle Thumbnails
  • RESEARCH PAPERS
    Inducement and activity analysis of antibacterial_related proteins/peptides in h ousefly larvae
    AN Chun-Ju, SHI Ming, HAO You-Jin, SHENG Chang-Zhong, GENG Hua, LI De-Sen, DU Rong-Qian
    2003, 46(5):  545-548. 
    Abstract ( 2921 )   PDF (2202KB) ( 1171 )     
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    Third-instar larvae of housefly (Musca domestica) were treated with different inducing methods including pricking, pricking with bacteria, heat shock, and ultrasonication, and collected at different times. The antibacterial activity was measured with liquid phase assay, and the antibacterial-related roteins/peptides were confirmed with stepwise regression model. The results showed that the above four treatments all could induce antibacterial substances. Among these induced proteins, X16 (22 kD) had activity against Micrococcus luteus and Escherichia coli, but X2 (50kD), X12 (26 kD), 22 (13 kD), X24 (7 kD) only had activity against either M. luteus or E. coli, and X7 (37 kD) had negative effect on antibacterial activity, which was deduced to be factors that stimulated cell to grow rapidly.
    Construction of transgenic vector pB[PUBnls_EGFP_prM] and identificatio n of its integrational function in mosquito cell
    GE Chun-Xi, HUANG Jiong-Lie, CHEN Guan-Jin, WU Yu*, YU Hong-Feng
    2003, 46(5):  549-552. 
    Abstract ( 3060 )   PDF (2229KB) ( 1077 )     
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    To explore a new method to control arthropod-borne diseases, prM gene from dengue virus was inserted into a transposon piggyBac based plasmid and an Insect transgenic vector pB[PUBnls-EGFP-prM] was constructed. The vector was used to transfect Aedes albopictus C6/36 cell with a helper plasmid. PCR and Southern blot tests showed that EGFP-prM gene had integrated into C6/36 cell genome. The results indicate that transposon piggyBac element is functional in Ae. albopictus and should be useful in further constructing dengue-refractory transgenic Ae. Albopictus.
    Biochemical characteristics of tyrosinase in the diamondback moth, Plutella xy lostella(L.)
    LIANG Pei, MENG Feng-Xia, GAO Xi-Wu*, ZHENG Bing-Zong, CHENG Gang
    2003, 46(5):  553-557. 
    Abstract ( 3316 )   PDF (361KB) ( 1172 )     
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    The optimum reaction conditions, sensitivity to the inhibitor and the developmental changes of tyrosinase in the diamondback moth, Plutella xylostella (L.), were studied using time-driving dynamic method. The results showed that the optimum pH of tyrosinase is about 6.4; The OD420 values are linear with time from 0-2 min. When stored at 22℃ and 4℃, the prepared tyrosinase could keep its best activity for 12 h and 72 h, respectively; and while stored at -20℃, the tyrosinase could keep its activity for at least 7 days. The activity of tyrosinase in different developmental stages of P. Xylostella follows the order pharate pupa>4th instar larvae >pupa>1st-3rd instar larvae > adult. The I50 of phenyl thiourea (PTU) to the activity of tyrosinase from both the resistant and susceptible strains showed no obvious difference (1.1796 μmol/L and 1.2795 μmol/L, respectively).
    Allometric growth and performance of the gastric caeca of Zonocerus variegatus (L.) (Orthoptera: Pyrgomorphidae)
    Bassey E. AKPAN1, Tony G. OKORIE2
    2003, 46(5):  558-566. 
    Abstract ( 3462 )   PDF (1270KB) ( 1154 )     
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    The allometry, growth and activities of the gastric caeca of Zonocerus variegatus(L.) were determined to find out the functions of its posterior caeca which are unknown. This was done by dissecting out the gut and measuring the main gut regions and the gastric caeca in the six nymphal stages and adult. The gut consists of three main regions; the crop, ventriculus, with gastric caeca attached at anterior rim, and the hindgut. Each set of caeca consists of a long anteriorly pointed arm and a short posteriorly pointed arm. The growth of the caeca relative to the main gut was allometric. The anterior caeca had higher growth ratios than the posterior caeca and both were highly correlated. The relationship between gut and caeca mean length was highly significant. The mean gut length and age were significantly correlated with growth rate exponent <1 indicating a decreasing growth increment with age. The mean caeca length and age were highly correlated with growth exponent >1 indicating an increasing growth with age. Females had higher mean lengths than males and this was highly significant (P<0.05). Males had higher growth ratios than females except at growth centres. The growth patterns of the caeca for wet and dry seasons were similar with a single growth centre. But the mean length of the caeca was significantly different between wet and dry season’s insects from the fourth instar to adult. The posterior caeca was considered a complementary structure to the anterior caeca. They perform the same function of digestion and absorption of food. The posterior caeca is concluded additional device to increase the surface area of the ventriculus to cope with low nutrient status of herbivory.
    Biochemical mechanism and genetics of resistance to lambda_cyhalothrin in th e beet armyworm, Spodoptera exigua, and the relative fitness of the resistan t strain
    LIU Yong-Jie1,2,SHEN Jin-Liang1*
    2003, 46(5):  567-572. 
    Abstract ( 2875 )   PDF (492KB) ( 965 )     
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    Comparison of the relative fitness of lambda-cyhalothrin resistant and susceptible strains of the beet armyworm, Spodoptera exigua (Hübner), indicated that the resistant strain possessed reproductive and developmental disadvantages, including lower pupation and oviposition rates, prolonged larval period and lighter weight. The biochemical mechanism of resistance to lambda-cyhalothrin was investigated using enzyme synergists (PBO, SV1, DEF and DEM) and enzymatic activity assays of esterase, glutathione S-transferase and microsomal O-demethylase. The synergistic ratios of PBO, SV1, DEF and DEM were 14.1, 14.8, 2.3 and 2.3 folds between resistant and susceptible strains respectively. Synergism to lambda-cyhalothrin by PBO and SV1 was the most distinct. This implied that mixed-function oxidase was involved in the resistance to lambda-cyhalothrin. The ratios of the enzymatic activity of esterase, glutathione S-transferase and microsomal O-demethylase in resistant and susceptible strains were 1.05, 0.91 and 1.05 folds, respectively. These results indicate that detoxification enzymes such as esterase, glutathione S-transferase and microsomal O-demethylase contribute little to the resistance of the beet armyworm to lambda-cyhalothrin. The results of genetic analysis indicated that lambda-cyhalothrin resistance in the beet armyworm appears to be controlled by two or more autosomal genes. The dominance degrees (D) of the F1 progenies from the reciprocal crosses (F1, R×S and F’1, R×S) were 0.61 and 0.43, respectively, and the major gene(s) involved is incompletely dominant. The resistant strain possessed 0.61 of the fitness value relative to the isogenic susceptible strain.
    Induction of mixed_function oxidases in the midguts of resistant and susceptible strains of the cotton bollworm, Helicoverpa armigera(Hübner)by phenobarb ital and fenvalerate
    QIU Li-Hong, ZHENG Ming-Qi, WANG Cheng-Ju, LI Xue-Feng, ZHANG Wen-Ji*
    2003, 46(5):  573-577. 
    Abstract ( 3498 )   PDF (367KB) ( 1026 )     
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    Phenobarbital (2 mg/g) and fenvalerate (0.2 mg/g) mixed in diets caused significant induction of cytochrome P450 and cytochrome c reductase in midgut of susceptible strain of the cotton bollworm, Helicoverpa armigera. The Induction ratios of phenobarbital and fenvalerate were all 2.24-fold to cytochrome P450, 1.33- and 1.40-fold to cytochrome c reductase, and 1.23- and 1.15-fold to cytochrome b5, respectively.Moreover, phenobarbital showed significant induction to activity of aldrin-epoxidase and ethoxyresorufin-demethylase in midgut of the strain, which was 2.75- and 2.66-fold respectively, but no induction to 7-ethoxycoumarin-deathylase activity (0.88-fold); fenvalerate showed 2.02-fold Induction to aldrin-epoxidase activity in the same tissue. To the resistant strain, phenobarbital and fenvalerate induced only cytochrome c reductase in midgut to significant level, which was 1.48-and 1.86-fold respectively. The induction ratios of phenobarbital and fenvalerate to cytochrome P450 in midgut of resistant strain were 1.21-and 1.15-fold respectively, while to cytochrome b5 only 1.15-and 0.98-fold respectively. In addition, fenvalerate caused 1.53-fold Induction of aldrin-epoxidase activity in midgut of resistant strain, while phenobarbital caused significant inhibition to it.
    Insensitivity of acetylcholinesterase and increased activity of esterase in the resistant cotton aphid, Aphis gossypii Glover
    LI Fei, HAN Zhao-Jun,TANG Bo
    2003, 46(5):  578-583. 
    Abstract ( 2913 )   PDF (444KB) ( 1352 )     
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    Resistant levels of cotton aphid strains collected from five different districts, Taian, Laiyang, Nanjing, Beijing and Anyang in China, designa ted as strainⅠ,Ⅱ,Ⅲ,Ⅳ and Ⅴ respectively, were determined with leaf-dip bioassay. The results Indicated that strain Ⅴ was the highest resistant while strainⅠ was the lowest resistant to conventional organophosphorus (OP) and carbamate pesticides, such as methamidophos, monocrotophos, pirimicarb and thiodicarb. Generally, the resistant levels of the five resistant strains were: Ⅴ>Ⅳ>Ⅲ,Ⅱ>Ⅰ. Compared with the sensitive strain 81-171B, the sensitivity of acetylcholinesterase (AChE) from strainⅡ, Ⅳ and Ⅴ apparently decreased and that from strainⅠand Ⅲ were relatively sensitive. The apparently decreasing of Km value indicated that AChE from strain Ⅳ and Ⅴ have been changed in quality. Esterase (total esterase and carboxylesterase) activity increased dramatically in different resistant strains. Esterase activity of strain Ⅲ is two times that from stain Ⅱ. Specially, Km value of carboxylesterase from strain Ⅴ reached 2460.4 μmol/L and that from strain Ⅳ decreased to 84.4 μmol/L It could be deduced that both increased esterase activity and reduced target sensitivity existed in all resistant strains. For lowlevel resistant cotton aphid strain, increased esterase activity plays a much more important role. However, either apparently increased esterase activity or reduced AChE activity in cotton aphid may result in middle-level resistance. Both dramatically increasing of esterase activity and reduction of AChE sensitivity are presented in high-level resistant strains of cotton aphid.
    Resistance of transgenic Bt cotton to the cotton bollworm I n cotton fields in Hubei Province
    DENG Shu-Dong1, XU Jing1, ZHANG Qing-Wen1*, ZHOU Shi-Wen2, XU Guan-Jun3
    2003, 46(5):  584-590. 
    Abstract ( 2596 )   PDF (516KB) ( 1192 )     
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    Systematic investigations in an experimental cotton field showed stable resistance of GK19, a cultivar of transgenic Bt cotton, to the cotton bollworm, Helicoverpa armigera (Hübner). The experiment included three treatments. The first was a transgenic Bt cotton plot that used pesticides to control pests, the second was a Bt cotton plot that relied on natural enemies to control pests, and the third was a routine cotton plot that adopted IPM (integrated pest management) to control pests. Cotton bollworm populations in the transgenic Bt cotton plots were controlled at very low levels with the maximal density being 12 per 100 cotton plants, even if no pesticides was sprayed throughout their growth stage. Bioassay in the laboratory showed that the weights of 6th instars larvae and pupae from the colony reared on the Bt cotton were 25.6% and 18.2% less respectively compared to those raised on routine cotton. Cotton bollworms that fed on Bt cotton grew slower and their generation duration was at least 17 days longer than those that fed on nonBt cotton. This resulted In reduced damage to transgenic Bt cotton plants.
    The community dynamics of predatory arthropods in both weed habitat and paddy fi eld from a double cropping paddy in Guangdong
    LIU Yu-Fang1, GU De-Xiang2, ZHANG Gu-Ren2
    2003, 46(5):  591-597. 
    Abstract ( 2788 )   PDF (530KB) ( 1112 )     
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    The community structure of predatory arthropods in a weed habitat and a neighboring paddy field from a double cropping paddy in Dasha Town, Guangdong Province was investigated with the suction sampler in 1998 In total, 73 predator species, including 55 species of spiders and 18 species of insects, were collected in the weed habitat. On March 21, when the field had been ploughed for planting early rice, 33 species of predatory arthropods were collected with the density of 130 predators /m2 in the weed habitat. On April 4, one week later the seedlings were transplanted, 29 species of predatory arthropods with the density of 92 predators /m2 and 12 species with the density of 16.2 predators /m2 were collected in the weed habitat and the rice field, respectively. On May 13, early rice coming to mature, only 19 species of predatory arthropods with the density of 28 predators /m2 were collected in the weed habitat while 27 species with the density of 53.2 predators /m2 were collected in the rice field. The similarity coefficients of the predatory arthropod communities in the weed habitat and the rice field were over 0.5, indicating many common species of predatory arthropods in the two habitats. These results suggest the community of predatory arthropods in weed habitat might be one of the main species pools for reestablishment of the community of in rice field.
    Interactions between the parasitoid Lysiphlebus japonicus Ashmead and its ho st Aphis craccivora Koch: host-stage selection and its effect on development
    GAN Ming1,2, MIAO Xue-Xia1, DING De-Cheng1*
    2003, 46(5):  598-604. 
    Abstract ( 6752 )   PDF (531KB) ( 1350 )     
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    Host-stage selection of Lysiphlebus japonicus Ashmead, a parasitoid of Aphis craccivora Koch and the effect of host stage being parasitized on the parasitoid development and fecundity were investigated at (25±1)℃. When aphids of mixed stages were provided, the parasitoid showed a preference for younger aphids to parasitize. The relative parasitism on the 2nd instar aphids was the highest (26.4%), followed by 1st instar aphids (20.6%), and rather low on the adults. The development of the aphids was delayed after being parasitized. The durations of the 1st, 2nd and the 3rd instar of the hosts significantly prolonged when 1st instar aphids were parasitized,and those of the 3nd and 4th instar were also markedly extended after alate were parasitized. However, no obvious influence on development of apterae and alate was observed after they were parasitized. The life span of the adults of the aphids parasitized at various nymphal stages sharply shortened. All of the parasitized 1st instar aphids turned to mummies before the adults. The fecundity of the adults from younger aphids parasitized distinctly declined in comparison with the control adults. Immature stage of the parasitoid In 2nd instar of the hosts developed the fastest with duration of 194.10h, and the slowest of 215.80 h in 1st instar of the hosts.Total contents of protein and glycogen in A.craccivora of different stages were also assayed.
    Biotype identification of the populations of Bemisia tabaci (Homoptera: Aleyrodidae) in China using RAPDPCR
    QIU Bao-Li1, REN Shun-Xiang1*, WEN Shuo-Yang1, Nasser S. MANDOUR1, 2
    2003, 46(5):  605-608. 
    Abstract ( 3107 )   PDF (1254KB) ( 2239 )     
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    Twentythree Bemisia tabaci (Gennadius) populations on vegetables, ornamental plants and weeds were collected from 23 different cities of 14 provinces in China. Biotypes of the different populations were identified and differentiated using a RAPD PCR method with a primer H16. The results showed that 17 whitefly specimens from 11 provinces were B biotype. The data is a good contribution in the distribution and control of Bemisia tabaci Bbiotype in China.
    Species diversity of litterlayer beetles in the Fengtongzhai National Nature R eserve, Sichuan Province
    YU Xiao-Dong, LUO Tian-Hong, ZHOU Hong-Zhang
    2003, 46(5):  609-616. 
    Abstract ( 3569 )   PDF (635KB) ( 1489 )     
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    The litter-layer beetle species diversity in Fengtongzhai National Nature Reserve (102°48′-103°18′ E,30°42′-30°54′ N) and adjacent areas, Sichuan, Southwest China was surveyed. Four local sites were selected to represent the degree of forest fragmentation and coverage of different vegetation. Fengtongzhai (elevation 1 680-2 080 m) is located in the core of the Nature Reserve and is covered with wellprotected native, mixed, broadleaved forests. Guobayan (elevation 2 280-3 340 m) is a site covered with various native vegetation types, but disturbed by intensive human activities. Mahuanggou (elevation 2 430-2 525 m) represents a site with a well-developed secondary coniferous lantation. Shuangshizhen (elevation 870-1 165 m) is covered with fragmented plantations surrounding by farmlands. Using mainly pitfall traps, we built up 26 plots to investigate how the species diversity of litter-layer beetles was influenced by factors such as forest fragmentation, elevation, slope aspect and habitat differentiation etc. Field collections were conducted from June 29 to July 5, 2001. During field research, a total of 2 338 beetle specimens were captured, of which the family Staphylinidae comprised 39.6%, Carabidae 29.3%, and Tenebrionidae, Curculionidae and Chrysomelidae each more than 5% of the total. These five families can be considered as common in the study area. Of the four local sites selected, Guobayan had the highest individual numbers, richness (S) and diversity (H′). Mahuanggou had the highest evenness (J) and the lowest value of richness. Shuangshizhen had the lowest values of diversity and evenness. Fengtongzhai was much more homogenous in habitat variations and thus did not show any extremes of diversity, evenness or richness. The beetle community in the fragmented forest of Shuangshizhen was very different from those at the other three sites. The community at Mahuanggou was more similar to that in Fengtongzhai than Guobayan. Four main types of vegetation were compared. Coleoptera, Staphylinidae and Carabidae were found to be more abundant in coniferous forest than in mixed broad-leaved forest. Tenebrionidae preferred shrub-land, and Chrysomelidae preferred coniferous forest. Curculionidae had the fewest individuals in bamboo. At Fengtongzhai and Guobayan, species and individuals of Coleoptera and dominant beetle families exhibited an overall tendency of increasing with elevation. In ten plots at Fengtongzhai, the northfacing plots were found to have the greater numbers of individual beetles, richness and diversity than the southfacing ones. Based on these results, weconclude that forest fragmentation, elevation, slope aspect, and vegetation variation (habitat types) influence the species diversity of the litter-layer beetle communities in Fengtongzhai National Nature Reserve. Therefore, for forest protection and restoration in this region, efforts to maintain or restore habitat heterogeneity will help to maintain or increase the species diversity of litterlayer beetles.
    Diversity of the moth community in the Qilihai wetland, Tianjin
    YOU Ping, LI Hou-Hun, WANG Shu-Xia, XU Jia-Sheng
    2003, 46(5):  617-621. 
    Abstract ( 2843 )   PDF (365KB) ( 1275 )     
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    The Qilihai wetland is situated in the northeast of Tianjin (39°16′-39°20′N, 117°29′-117°39′E). An investigation on the diversity of its moth community was carried out from June 21 to October 6 in 2001 and from April 21 to October 21 in 2002. A total of 198 moth species belonging to 153 genera in 19 families were collected. The results show that the curve of the moth speciesabundancewas in accordance with the lognormal hypothesis. However, no significant correlation was found between indices of diversity and evenness (r=-0.47) but Indices of diversity and richness was significantly correlated (r=0.95). This suggests that the environmental quality of the Qilihai wetland be deteriorating.
    A new hemeroscopid dragonfly from the Lower Cretaceous of Northeast China (Odonata: Hemeroscopidae)
    REN Dong1,LIU Jin-Yuan2,CHENG Xiao-Dong2
    2003, 46(5):  622-628. 
    Abstract ( 3476 )   PDF (2393KB) ( 1107 )     
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    A new genus and species of hemeroscopid dragonfly, Abrohemeroscopus mengi gen. Et sp.nov., of the family Hemeroscopidae Pritykina, 1977, from the Lower Cretaceous Jiufotang Formation, Liaoning Province, Northeastern China, is described and illustrated. This new genus is rather similar to Hemeroscopus Pritykina,1977, but differs from the latter in the following characters: (1) hindwing anal loop is smaller, only with 6-7 cells (plesiomorphy); (2) Rspl is absent (plesiomorphy); (3) the hindwing vein CuAa is curved and has five distinct posterior branches (plesiomorphy); (4) the forewing MP is not shortened, reaching the posterior wing margin slightly beyond the level of the nodus (plesiomorphy); (5) pterostigmata more distinctly braced (plesiomorphy); (6) the hindwing area between MP and CuAa is narrow, with only one row of cells near the discoidal triangle (plesiomorphy). This is the oldest fossil record of the Hemeroscopidae in China.
    A study on the genus Herochroma Swinhoe in China, with descriptions of four new species (Lepidoptera: Geometridae, Geometrinae)
    HAN Hong-Xiang, XUE Da-Yong*, LI Hong-Mei
    2003, 46(5):  629-639. 
    Abstract ( 3134 )   PDF (4041KB) ( 1414 )     
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    Four new species of the genus Herochroma are described: H. curvata sp. Nov. from Hainan and Guangxi, H. pallensia sp. Nov. from Guangxi,Hunan and Fujian, H. perspicillata sp. Nov. From Yunnan, and H. rosulata sp. Nov. from Hainan. The male of H. mansfieldi (Prout) is recorded and described for the first time. Illustrations of moths and genitalia of new species and a key to all species from China are provided. H. yazakii Inoue is firstly recorded to the fauna of China.
    A review of the genus Napomyza Westwood in China (Diptera: Agromyzidae)
    CHEN Xiao-Lin, WANG Xing-Jian*
    2003, 46(5):  640-643. 
    Abstract ( 2591 )   PDF (267KB) ( 1215 )     
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    Six species including two new species of the genus Napomyza Westwood are recognized: N. annulipes (Meigen), N. hirticornis (Hendel), N. lateralis (Fallen), N. paratripolii sp. Nov, N. plumea Spencer and N. xizangensis sp. Nov. Descriptions and illustrations of new species are given; diagnoses and a key to the known Chinese species are also provided.
    Design and development of Taxokeys, a dichotomousreasoningbased multimedia expert system assisting insect identification and taxonomic study
    GAO Ling-Wang, SHEN Zuo-Rui, LIU Zhi-Qi, MA Xiao-Guang
    2003, 46(5):  644-648. 
    Abstract ( 3102 )   PDF (1986KB) ( 1182 )     
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    This paper describes the design and development of the platform of a multimedia expert system to assist taxonomic identification, as well as the characteristics of the system. This system, named Taxokeys, is based on the dichotomous reasoning method. From expertise of insect taxonomy, dichotomous taxonomic keys for the Insecta can be revised into a knowledge database in terms of data structure using computer technology. This database can then be used as the basis for insect identification by searching for nodes within dichotomous trees of the data-structure until the final node is reached. In fact, the system is a generalIzed platform for insect taxonomists to develop their own multimedia expert systems. Taxokeys has such features as ease of adding new data, simplicity in design, and simplicity of operation, and may be useful for biological identification and taxonomic study in general. The possibility of increasing additional functions and potential applications for this system are discussed.
    Advances in insect picornavirus research
    WANG Xiao-Chun, HU Yuan-Yang*, ZHANG Jia-Min
    2003, 46(5):  649-954. 
    Abstract ( 2938 )   PDF (460KB) ( 1453 )     
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    According to the characteristics of the genome structure of insect picornaviruses, they can be divided into three groups: infectious flacherie virus(IFV) group, cricket paralysis virus(CrPV) group and Acyrhosiphon pisum virus (APV) group. The initiation of protein translation of insect picornavirus is unique: independent of map structure, and initiation factors eIF1 and eIF1A and map combined protein eIF4E are not necessary; furthermore, the translation of capsid protein of CrPV group and APV group initiate from internal ribosome entry site and the initiation code is CUU. The paper also reviewed advances on replication mechanism of insect picornavirus and the phylogeny among insect, mammal and plant picornaviruses or icorna-like viruses.
    Histopathological changes of Pieris rapae (L.) larvae infected by Verticillium lecanii (Zimm.) viega
    ZHANG Xian-Hong,LI Wen-Ying,HE Yun-Chun,WANG Jian-Ming, HAO Chi
    2003, 46(5):  655-659. 
    Abstract ( 2998 )   PDF (4709KB) ( 1183 )     
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    A histopathological study on Pieris rapae (L.) larvae infected by Verticillium lecanii (Zimm.) viegas showed that the fungi infected the insect body mainly by penetrating the cuticle. The conidia on the cuticle of P. rapae larvae germinated in 12 h after inoculation. The hyphae penetrated the cuticle of the 2nd and 3rd instar larvae in 24 h and pathogenesis started on their fat body in 48 h. The hyphae penetrated the cuticle of 4th and 5th instar larvae in 36 h. Some hyphae were observed inside the body in 48 h. Invasion of the hyphae upon the host tissues showed no significant selection. They grew in hemolymphs firstly and then entered the fat body and the muscle. As the hyphae grew, the mid gut and the malpighian tube and the silk gland were infected successively. Pathological changes occurred on all infected tissues and organs, including cuticle disintegration, malformation and dissolution of the fat body, loose muscle fibre layout, disappearance of cells of the midgut epithelium and vacuolization.
    The structureactivity relationship of aphid alarm pheromone analogues
    YANG Xin-Ling1, KAN Wei2, HUANG Wen-Yao1 , ZHANG Zhong-Ning2*
    2003, 46(5):  660-664. 
    Abstract ( 3049 )   PDF (343KB) ( 1188 )     
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    The structures of mono-fluoro analogues of (E)-β-farnesene (EBF), the main component of the aphid alarm pheromone of many aphid species, were compared with EBF using AccuModel and PowerFit software. The structures of EBF04, EBF05 and EBF12 with the lowest fitting energy are more similar to EBF. The lowest energy structures of eleven analogues of non-farnesene were also studied. The results indicated that the direction of the numerical value of torsion angle, especially H25-C4-C5-C1 and C5-C6-C7-C8, plays an important role in the compounds activity of alarm pheromone.
    Identification of sex pheromone components of Holcocerus hippophaecolus (Le pidoptera: Cossidae) and their biological activities
    FANG Yu-Ling1, SUN Jiang-Hua1, ZHAO Cheng-Hua1, SUN Yong-Ping2, ZHENG Hong-Qi3, ZHANG Zhong-Ning1*
    2003, 46(5):  665-666. 
    Abstract ( 2638 )   PDF (166KB) ( 1182 )     
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    We identified the structure and component of sex pheromones of Holcocerus hippophaecolus (Lepidoptera: Cossidae), a destructive pest to Hippophae rhamnoidea growing in Northern China. Electroantennogram responses and field trapping effects by sex pheromones with different components were also studied. Seven components in an extract of sex gland were identified: (Z)-3-tetradecen-1-ol, (Z)-3-tetradecenyl acetate, (E)-3-tetradecen-1-ol, (E)-3-tetradecenyl acetate, (E)-7-tetradecen-1-ol, (E)-7- tetradecenyl acetate and (Z)-9-tetradecenyl acetate. Results of the field trapping tests showed the biological activities of mixtures of two or five components are stronger than any single one.