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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 August 2004, Volume 47 Issue 4
For Selected: View Abstracts Toggle Thumbnails
    Cloning, identification and expression profiling of the cDNAs of odorantbinding proteins in the malaria mosquito, Anopheles gambiae
    LI Zheng-Xi1, Jing Jiang-ZHOU2
    2004, 47(4):  417-423. 
    Abstract ( 2503 )   PDF (531KB) ( 979 )     
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    Olfaction plays a major role in host finding and selection of malaria mosquitoes . The African malaria mosquito, Anopheles gambiae is a highly anthropophilic malariatransmitting vector. Two odorant binding protein (OBP) candidates (agLZ3788 and agLZ9988) have been identified using RT-PCR and standard molecular cloning techniques, based on its whole genomes equences. Sequencing and analysis showed that these two OBP genes are characterized by typical insect OBP motif. Furthermore, semi-quantitative RT-PCR was employed to study the spatial expression patterns of them, and the results demonstrated that they were not only expressed in female antennae, but also in other tissues, especially in mosquito legs. This finding indicates that mosquito OBPs might have other functions than binding odorants, and thus provides an important scientific basis for further recombinant and functional studies of mosquito OBPs.
    Transmission of dengue 2 virus by diapausing eggs of Aedes albopictus
    GUO Xiao-Xia1, ZHAO Tong-Yan1*, DONG Yan-De1, JIANG Shu-Nan2, LU Bao-Lin1
    2004, 47(4):  424-428. 
    Abstract ( 2600 )   PDF (288KB) ( 1097 )     
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    Virus isolation in C6/36 cells was used for detection of the infection rates of F1 progeny from diapausing eggs of infected Aedes albopictus. Eggs from three gonotrophic cycles (GC) were collected, and vertical transmission was not observed in the first gonotrophic cycle, while there was no significant difference observed between the infection rates of the GC2 progeny and that of the GC3 progeny (P>0.05). The total positive rate of pools was 9.1%, and the minimum infection rate was 1∶330. The results of indirect fluorescent antibody test showed that F1 adult mosquitoes obtained from diapausing eggs can transmit dengue 2 virus to sensitive mice horizontally through biting. The horizontal transmission rate was 6.1%. These results indicate that dengue 2 can be transmitted vertically even the infected eggs are induced into diapausing, and F1 adult mosquitoes raised from diapausing eggs can transmit dengue 2 virus to sensitive mice horizontally via biting.
    Modulations by cAMP and cGMP of the highvoltage activated Ca2+ channels in the central neurons of the cotton bollworm, Helicoverpa armigera
    LI Jie1,2, DU Yu-Zhe1, TONG Fan1, HE Bing-Jun1, LIU An-Xi1
    2004, 47(4):  429-433. 
    Abstract ( 2617 )   PDF (307KB) ( 926 )     
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    The effects of cAMP and cGMP on the high-voltage activated (HVA) Ca2+ channels in the central neurons isolated from the 3rd instar larvae of the cotton bollworm (Helicoverpa armigera) were studied using the whole cell patch clamp technique. With barium as current carrier, the currents of Ca2+ channels were recorded by blocking Na+ and K+ currents. Extracellular application of 0.1 mmol/L forskolin, a stimulator of adenylyl cyclase (AC), had no effect on the peak amplitude of Ba2+ currents. In contrast, 1 mmol/L cGMP in the intracellular solution suppressed the current amplitude significantly and the inhibition was time and dose dependent. The results suggest that the activities of HVA Ca2+ channels in the cotton bollworm may not be affected by the elevated cAMP, but can be inhibited by the increased cGMP.
    Activation of prophenoloxidase by Zoophthora radicans isolates from different hosts in hemolymph of Plutella xylostella larvae (Lepidoptera: Plutellidae)hosts in hemolymph of Plutella xylostella larvae (Lepidoptera: Plutellidae)
    LIU Qing-E1,2, XU Jun-Huan1*, FENG Ming-Guang1
    2004, 47(4):  434-438. 
    Abstract ( 3003 )   PDF (360KB) ( 959 )     
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    The activation of prophenoloxidase (ProPO) in the hemolymph of the diamondback moth Plutella xylostella larvae against infection of Zoophthora radicans isolates from different hosts was investigated. The ProPO was found primarily on the membrane or inside host hemocytes, but less in plasma. When laminarin as an immune activator was present, phenoloxidase (PO) activities in cell debris, hemocyte lysate solution and plasma were measured as 26.80, 16.68, and 2.53 U, respectively. The ProPO was significantly activated by laminarin present in the plasma due to a much higher PO activity than that when the laminarin or the plasma was tested alone. The ProPO activity increased by 2.9-3.4-fold when the lysate of Z. radicans mycelia was present in host plasma. Among the four isolates tested, the PO activity was highest in ARSEF1342, medium in ARSEF2699 or F99101, but lowest in ARSEF1100. Furthermore, the activated PO in the mycelia of Z. radicans caused melanism, an evidence of the immune defending response of hosts to fungal infection. The PO activity was triggered most conspicuously by ARSEF1342 than by ARSEF2699 or F99101, but very weakly in ARSEF1100. The fact of the more attachment of the PO to the laminarin than to Z. radicans isolates revealed a trend that the fungal pathogen may to some extent evade from the host immune response. This was further revealed by the correlation between the virulence of different isolates against P. xylostella and the ProPO activation by the isolates or the following PO activities in the lysates of their mycelia.
    Identification and cDNA sequencing of vitellogenin in Bombyx mandarina Moore
    DONG Sheng-Zhang, LIU Chao-Liang*, WANG Tai-Chu, ZHU Bao-Jian
    2004, 47(4):  439-443. 
    Abstract ( 3053 )   PDF (440KB) ( 1053 )     
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    The large subunit and small subunit of vitellogenin in Bombyx mandarina were identified through SDS-PAGE and Western blot, with molecular weight about 175 kD and 42 kD respectively based on high molecular weight marker. Several primers were designed according to cDNA sequence of vitellogenin in Bombyx mori and conservatism of insect vitellogenin. The cDNA sequence of vitellogenin in Bombyx mandarina (GenBank accession number: AY309967) was obtained through RT-PCR of the total RNA and RACE amplification of 3′end and 5′end. This sequence contains 5 754 bases, an open reading frame which encodes 1 780 amino acids, and the putative cleavage sites RSRR for the proteases of the subtilisin family at position 364-367 where provitellogenin is cleaved into two subunits. The molecular weights of the two subunits are 161.571 kD and 40.794 kD respectively based on amino acids, which are in accordance with the SDS-PAGE results if modification after translation is considered. The results of homology analysis suggested that amino acid sequence of insect vitellogenin be highly conserved within the same order for insects.
    Histochemistry of three enzymes in newly emerged and engorged adults of rat fleas Monopsyllus anisus (Rothschild) and Leptopsylla segnis (Schonherr)
    XUN Hui, QI Yi-Ming
    2004, 47(4):  444-448. 
    Abstract ( 2922 )   PDF (2321KB) ( 829 )     
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    The distribution and activity of alkaline phosphatase (AKP), acid phosphatase (ACP) and adenosine triphosphatase (ATPase) in newly emerged and engorged adults of Monopsyllus anisus (Rothschild) and Leptopsylla segnis (Schonherr) were studied with histochemistry techniques and image analysis of microscope photographs. The results indicated that in newly emerged adults, alkaline phosphatase (AKP) and acid phosphatase (ACP) were mainly distributed in midgut, nerve nucleus, testis, ejaculatory duct, oviduct and spermathecal gland, while adenosine triphosp hatase (ATPase) was distributed in all tissues. After blood ingestion and digestion, the activity of three enzymes increased in midguts. In engorged adults, except that the activity of alkaline phosphatase (AKP) decreased 72 hours after blood ingestion, there was no significant difference in the increasing degree of the activity of the three enzymes in other time after blood ingestion. The activity of the three enzymes also increased during growing up of oocytes.
    A mutation in sodium channel gene associated with pyrethroid resistance in Bemisia tabaci (Gennadius) and its detection
    WANG Li-Hua, WU Yi-Dong*
    2004, 47(4):  449-453. 
    Abstract ( 2777 )   PDF (440KB) ( 1278 )     
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    A mutation, leucine to isoleucine at position 925 (L925I) in the ⅡS4-6 linker of the para-type sodium channel protein from the Nanjing strain (B-biotype) of the tobacco whitefly, Bemisia tabaci (Gennadius) was identified to be associated with pyrethroid resistance. The DNA-based genotyping technique PASA (PCR amplification of specific allele) for rapid detection of the L925I mutation was established. The Nanjing strain collected from cottons in Nanjing in 2002 showed 77-fold resistance to cypermethrin compared with the susceptible SUD-S strain. The resistance to cypermethrin in the selected Nanjing strain increased to 227-fold afterseveral selections with cypermethrin. PASA genotyping results indicated that 100 % individuals from the selected Nanjing strain had L925I mutation (61.1% homozyg otes and 38.9% heterozygotes), whereas only 75% individuals from the unselected Nanjing strain had L925I mutation (35% homozygotes, 40% heterozygotes and 25% wild type ). Our results indicated that L925I mutation was tightly associated with pyrethroid resistance in the tobacco whitefly from Nanjing. Possible metabolic mechanisms for pyrethroid resistance in this strain were discussed.
    Dynamics of Cry1Ab protein from transgenic Bt rice in herbivores and their predators
    JIANG Yong-Hou1,2,3, FU Qiang3, CHENG Jia-An1*, ZHU Zeng-Rong1, JIANG Ming-Xing1, YE Gong-Yin1, ZHANG Zhi-Tao3
    2004, 47(4):  454-460. 
    Abstract ( 2774 )   PDF (456KB) ( 1124 )     
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    Levels of Cry1Ab protein in several herbivores and their predators through food chain from transgenic Bt rice (KMD1) were studied in the laboratory. The results showed that the levels of Cry1Ab in stripped stem borer (SSB) Chilo suppressalis continuously feeding on KMD1 or on Xushui 11 control rice after feeding on KMD1 for 36 h declined with time at the booting stage as well as at the maturing stage. Levels of Cry1Ab in Mycalesis gotama continuously feeding on KMD1 or on Xushui 11 control rice after feeding on KMD1 for two days declined with time, but more dramatically than those of SSB. High levels of Cry1Ab were detected in faeces of both C. suppressalis and M. gotama, but no Cry1Ab detected in their controls. 3.5 ng/g Cry1Ab was detected in the haemolymph of C. suppressalis feeding on KMD1 Different levels of Cry1Ab were all detected in brown planthopper (BPH) Nilaparvata lugens, rice aphid (RA) Sitobion avenae reared on KMD1, and wolf spider (WS) Pirata subpiraticus fed with preys that had ingested KMD1. The concentration of Cry1Ab protein in P. subpiraticus fed with M. gotama larvae reared on KMD1 was about 60 times higher than that in P. subpiraticus fed with C. suppressalis reared on KMD1 for 36 h, and no Cry1Ab protein was detected in their controls. These results indicated Cry1Ab protein could be transferred along food chain.
    Effect of Bt protein on development of different strains of the cotton bollworm,Helicoverpa armigera (Hübner) and the parasitoid, Microplitis mediator(Haliday)
    LIU Xiao-Xia1, ZHANG Qing-Wen1*, CAI Qing-Nian1, LI Jian-Cheng2, DONG Jie1
    2004, 47(4):  461-466. 
    Abstract ( 2575 )   PDF (393KB) ( 1133 )     
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    Two strains of the cotton bollworm, Helicoverpa armigera (Hübner), one is a susceptible laboratory strain and the other is collected from Bt cotton fields, were used as the insect hosts to study the effect of Bt insecticidal protein on the development of the parasitoid, Microplitis mediator (Haliday). The results showed that the larval duration of the parasitoid was delayed, and the pupal weight, body weight of the newly emerged adult and adult longevity decreased significantly when the hosts larvae fed on diet containing Bt protoxin Cry1Ac at the concentrations of 0.5-8.0 μg/g in all time or from 12 h before parasitismtill pupation of the parasitoid . Compared with the control, the larval weight and pupal weight of H. armigera decreased significantly when the larvae fed on diet containing cry1Ac. Pupation rate of H. armigera decreased significantly in the treatment with diet containing Cry1Ac at 4 .0 μg/g. When H. armigera larvae fed on the transgenic cott on leaves expressing both Cry1A and CpTI proteins, the mortality of the laboratory strain was 48.5%-95.8% in 2-5 days after treatment, which was significantly higher than that of the field strain (30.9%-86.1%). It is concluded that feeding on diet containing Bt insecticidal protein, both strains of the cotton bollworm will have significantly negative effects on deve lopment of the parasitoid, M. mediator.
    Re-migration capacity of the white-backed planthopper, Sogatella furcifera (Horvath)
    WANG Yuan-Kun, ZHAI Bao-Ping
    2004, 47(4):  467-473. 
    Abstract ( 3169 )   PDF (382KB) ( 1079 )     
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    Re-migration potential of the white-backed planthopper (WBPH), Sogatella furcifera (Horvath) after a long journey and feeding on different varieties of rice was tested and simulated with tethered flight on a set of computerized flight mill. The results revealed that WBPH in the rice cropping areas of the Yangtze River consisted of individuals with different flight characteristics, namely, the sedentary type (flight duration less than 3. 0 min), migratory type (flight duration more than 30 min), strong migratory type (flight duration more than 420 min) and re-migratory type (2nd tethered flight duration more than 30 min). The proportion of the re-migratory type was 5.7% among all of 558 tested WBPH and 28.6% among 112 individuals of the migratory type. The flight capacity and re-migration potential of WBPH were influenced significantly by the nutritive conditions of the rice varieties. The individuals feeding on the hopper-sensitive varieties showed higher proportion of the re-migratory type (>5%) and stronger ability of migration. When fed on a less sensitive variety and a hopper-tolerance variety before and after the first tethered test, the flyer would perform poor re-migration flight and lower proportion of the re-migratory type. But the hoppers would exhibit higher proportion of the re-migratory type and medium-grade flight duration if they fed on a tolerance variety both before and after the first tethered test. The individuals with sustained flight over 360 min during the first tethered test performed higher ability of re-migration. The copulation status only affected the 6 day-old females and 2 day-old males significantly.
    Effect of false flax (Camelina sativa) on larval feeding and adult behavi oral response of the diamondback moth (Plutella xylostella)
    DENG Shu-Dong, YUN Gui-Ling, ZHANG Qing-Wen*, XU Huan-Li, CAI Qing-Nian
    2004, 47(4):  474-478. 
    Abstract ( 2457 )   PDF (329KB) ( 1030 )     
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    Effective sections and sensitive characters of courtship signals in the rice brown planthopper, Nilaparvata lugens (Stal)
    YAO Qing, LAI Feng-Xiang, FU Qiang, ZHANG Zhi-Tao
    2004, 47(4):  479-484. 
    Abstract ( 2649 )   PDF (336KB) ( 1005 )     
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    Different sections of courtship signals and their combinations in the rice brown planthopper Nilaparvata lugens (Stal) were played back. Synthesized signals with different pulse repetition frequencies and main vibration frequencies were presented to the rice brown planthoppers. The results showed that the acoustic sections consisted of regular and continuous multi-pulses were effective in planthopper mating recognition. The pulse repetition frequency was an important sensitive signal character in planthopper mating choice. The sensitive ranges of pulse repetition frequency were narrow, 70-90 Hz for the female and about 22 Hz for the male; but the sensitive ranges of their main vibration frequency were wide, 200-1 700 Hz for the female and 100-300 Hz for the male.
    A systematic study on the genus Nuntiella Kuznetsov (Lepidoptera: Tortricidae: Olethreutinae)
    ZHANG Ai-Huan, LI Hou-Hun
    2004, 47(4):  485-489. 
    Abstract ( 2698 )   PDF (2933KB) ( 965 )     
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    Descriptions of three species of the genus Nuntiella Kuznetsov are given in this paper. Two species ( Nuntiella laticuculla sp. Nov. and Nuntiella angustiptera sp. Nov.) are described as new to science and the female of Nuntiella is reported for the first time. The photographs of the adults and the genital structures are provided. A key to the described species is given.
    A taxonomic revision of the genus Loxoneura Macquart from the Oriental Region, with description of one new species(Diptera: Platystomatidae)
    WANG Xing-Jian, CHEN Xiao-Lin
    2004, 47(4):  490-498. 
    Abstract ( 2455 )   PDF (1704KB) ( 1145 )     
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    The genus Loxoneura Macquart (Diptera: Platystomatidae) of the Oriental Region are revised and the generic characters are discussed. A total of 12 species are presently recognized, of which L. tibetana Wang et Chen from China is described as new to science. New geographical distributions of five species are reported, among which L. fascialis Kertesz, L. livida Hendel and L. pictipennis (Walker) are newly recorded from China; L. decora (Fabricius) is newly recorded from Malaysia and Borneo; L. formosae Kertesz is newly recorded from India. Moreover, a key to the species, diagnoses of all species and illustrations of wings and genitalia for some species are provided.
    Host biotypes and their formation causes in aphids
    LIU Xiang-Dong, ZHANG Xiao-Xi, ZHAI Bao-Ping
    2004, 47(4):  499-506. 
    Abstract ( 2879 )   PDF (586KB) ( 1182 )     
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    The possible causes of the formation of aphid host biotypes were reviewed. In ecological levels, the formation is mainly related with the selection capacity to host plants, the natural enemies, the symbionts (coexists ) and resistance to insecticides, and so on. The host biotypes have their genetic bases, including the mutation or change in enzymes and chromosomes, sexual reproduction, assortive mating and genetic differentiation of population. But the detailed causes for a certain host biotype in aphids were poorly understood at present.
    Plant resistance to insects induced by application of exogenous jasmonic acid and methyl jasmonate
    GUI Lian-You1,2, LIU Shu-Sheng1, CHEN Zong-Mao2*
    2004, 47(4):  507-514. 
    Abstract ( 4758 )   PDF (514KB) ( 1241 )     
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    This article reviews the molecular structures of jasmonic acid (JA) and methyl jasmonate (MJA), the resistance to insects by plants induced by application of exogenous JA and MJA and the induction mechanisms. In many plants, defense systems against insect herbivores can be induced by application of exogenous JA or MJA. Exogenous JA or MJA can activate plant defense genes either via the octadecanoid pathway or acting directly on the genes. Activation of defense genes leads to metabolic reconfiguration to produce the following four types of responses: (1) direct defense: production of toxic compounds, protein ase inhibitors and oxidative enzymes, and behaviour-modifying volatiles against herbivores; (2) indirect defense: production of volatiles for recruiting natural enemies of herbivores; (3) no defense; and (4) negative defense: production of volatiles attractive to herbivores.
    Advances in evolution of insecticide resistance in parasitoid wasps
    WU Gang1, JIANG Shu-Ren2
    2004, 47(4):  515-521. 
    Abstract ( 2693 )   PDF (525KB) ( 1163 )     
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    Specific interactions were involved in host plant-herbivore-parasitoid system based on the adaptive strategies and coevolution on tritrophic interactions. The evolution of insecticide resistance in both herbivore and parasitoid wasps was affected by selection pressure. However, different evolution models of insecticide resistance might exist in parasitoids and herbivores with different biological and ecological characteristics. The present results showed that the evolution of insecticide resistance in parasitoids could be affected either directly by exposing to the spray in the field, or indirectly by the factors including the insecticides penetrated into the body of host insects, plant allelochemicals fed by host insects, and climatic factors.
    Cloning and sequence analysis of an ubiquitin gene of Blattella germanica
    YU Hang, JIN Feng-Liang, XU Xiao-Xia, YANG Xing, GU De-Xiang, ZHANG Wen-Qing*
    2004, 47(4):  522-525. 
    Abstract ( 2451 )   PDF (261KB) ( 1013 )     
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    The coding sequence of Blattella germanica ubiquitin gene was cloned and determined (GenBank Accession No. AY501003). The length of this opening reading-frame (ORF) is 228 bp, encoding a protein with molecular weight of 8.47 kD and isoelectric point of 5.73.Multiple sequence alignment indicated that B. germanica ubiquitin was very similar to the homologous proteins of other eukaryotic species and shared more than 94% identity with other eukaryotic ubiquitins at amino acid level.
    Cloning and analysis of DNA sequences related to deltamethrin resistance in the diamondback moth, Plutella xylostella (L.)
    CHENG Luo-Gen1, CHEN Zhi-Hao2, ZHANG Xiao-Fei1, LI Zhong-Ying2
    2004, 47(4):  526-529. 
    Abstract ( 2503 )   PDF (525KB) ( 1090 )     
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    Using representational difference analysis (RDA) technique,the genomic difference between the susceptible strain and the deltamethrin resistance near isogenic line of the diamondback moth, Plutella xylostella (L.) was preliminarily analyzed. In RDA system, the driver amplicon is from the susceptible strain while the tester amplicon from the deltamethrin resistance near isogenic line strain. After three rounds of subtractive hybridization, the differential amplification products were obtained and their sizes were about 150-300 bp. Comparisons between our sub-clone sequencing results and those recorded in GenBank show that these products have partial gene homology with Homo sapiens, bronchitis virus and so on, but show no homology to any known resistant gene. Preliminary judgment revealed that these segments might be new gene sequences or controlling gene sequences.
    Changes in content of hemolymph protein in the honeybee (Apis mellifera L.) workers infected by Nosema apis and Varroa destructor respectively
    ZHOU Ting, YAO Jun, WANG Qiang, WANG Feng-Zhong
    2004, 47(4):  530-533. 
    Abstract ( 3474 )   PDF (337KB) ( 1128 )     
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    The changes in content of hemolymph protein in the honeybee (Apis mellifera L.) workers infected by spores of Nosema apis and the mite Varroa destructor (Acari: Va rroidae) respectively were assayed. The content of hemolymph protein was detected using Bradford method. The component difference of hemolymph proteins between the healthy (CK) and the infected bees were analyzed using high voltage isoelectric focusing electrophoresis (IEF). The results showed that the content of hemolymph protein of the bees tended to rise progressively within 10 days after being infected by Nosema spores, and then decreased gradually, till reaching a level below the content before being infected in 12-27 days after infection. The content of hemolymph protein of the bees infected by V. destructor was significantly higher than that of the control, and the components of hemolymph proteins were also different between the healthy and infected bees as indicated by IEF results. The results suggested the honey bees developed immunological reaction in some degree to N. apis or V. destructor after their infection.
    Histological changes in the midgut epithelium of Ixodes sinensis after biting naive and immunized New Zealand white rabbits
    LIU Zhi-Gang1, YE Bing-Hui2,ZHU Qing-Xian3
    2004, 47(4):  534-537. 
    Abstract ( 2690 )   PDF (1736KB) ( 1073 )     
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    The histological changes in the midgut epithelium of Ixodes sinensis were examined under light microscope and electron microscope at different times (24 h, 48 h, 72 h, 5 d and 8 d) after the first biting on naive New Zealand rabbits and the second biting on the rabbits immunized by the first biting. The results indicated that after the first biting, the digestive cells of I. Sinensis become more in number and larger in size, with microvilli closely and regularly arranged, organelles enriched, unit membrane clearly seen, and vacuoles, a large number of lipid droplets and haematin granules appearing. These cells also developed a highly infolded basal lamina, forming a labyrinth system. By contrast, after the second biting, the midgut epithelium of I. Sinensis revealed rather strikingly pathological changes with the basal lamina becoming thinner, looser and broken; digest cells damaged and vacuolated; microvilli decreased in number, shortened and disarranged; the mitochondria swollen and its crests reduced, shortened and even with myeloid changed; the rough endoplasmic reticulum dilated; lipid droplets and haematin granules decreased in number; phagocytic and pinocytic activity weakened; and basal labyrinth system vacuolized. The results suggested that the first biting results in immunodefense reaction of hosts and the tick midgut was the primary immunological target of hosts after the second biting.
    Effect of transgenic Cry1Ac+CpTI cotton (SGK321) on population dynamics of pests and their natural enemies
    ZHOU Hong-Xu1,2, GUO Jian-Ying1,3, WAN Fang-Hao1*
    2004, 47(4):  538-542. 
    Abstract ( 3541 )   PDF (278KB) ( 933 )     
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    Effects of transgenic cotton (cv. SGK321, with inserted genes of Cry1Ac and CpTI) on population dynamics of pests and natural enemies were studied in Nanpi County, Hebei Province in 2002. It showed that the composition of pest and predatory species was similar between the plots of transgenic cotton SGK321 and its parental line, sy321 cotton, but with different accumulated numbers for each species. From 24 surveys during May 23-September 16, the accumulated number of the main pest species decreased in SGK321, compared to those of sy321, by 89.5%, 64.5%, 21.8%, 15.6% and 33.7% for Helicoverpa armigera, Aphis gossypii, Lygus lucorum, Bemisia tabaci and Empoasca flavescens, respectively. For the main natural enemies, the accumulated numbers of Propylaea japonica and Chrysopa sinica increased by 34.0% and 9.1%, respectively during the same period; but those of Harmonia axyridis, Orius minutus, Campylomma diversicornis, Lysiphlebia japonica and spiders decreased by 28.6%, 6.5%, 43.1%, 44.7% and 14.0%, respectively. Population dynamics of the main pest and predatory species showed that the population peak of A. gossypii, E. flavescens and B. tabaci occurred from the middle to late July, late August to mid-September, and late August to early and mid-September, respectively. And the individual number of each pest species was lower in SGK321 plot than in sy321 during its peak period. The population peak of P. japonica lasted from the early July to middle and late August, and its number is higher in SGK321 plot than in sy321 during this period. The results suggested that the transgenic cotton SGK321 had control efficiency not only to the cotton bollworm, but also to some non-target pests, such as the cotton aphid and the tobacco whitefly. The individual numbers of P. japonica and C. sinica increased in SGK321 plot, compared to those in sy321, but those of other main natural enemy species decreased, indicating some negative effects of the transgenic cotton SGK321 on natural enemy populations.