The second internal transcribed spacers (ITS2) of six Trichogramma species, i.e. T. dendrolimi Matsumura, T. ostriniae Pang et Chen, T. chilonis Ishii, T. evanescens Westwood, T. brassicae Bezdenko and T. embryophagum (Hartig) were cloned and sequenced, and the homological sequences available in GenBank retrieved for DNA alignment and clustering. The feasibility of the application of ITS2 sequences to the phylogenetic reconstruction and molecular identification of different Trichogramma species was then evaluated. Meanwhile, six geographical populations of T. dendrolimi, i.e., populations collected from Yabuli in Heilongjiang (YBL), Changchun in Jilin (JL), Renhe in Jilin (RH), Chang'an in Shaanxi (CHA), Xuzhou in Jiangsu(XZ) and Guangzhou in Guangdong(GZ), were used to determine ITS2 divergence between subspecies populations. Alignment of sequenced ITS2s showed that they were highly conserved within intraspecific taxa but that significant genetic distances existed between interspecific taxa. Comparison and analysis of an outgroup led to the clear conclusion that ITS2 is suitable only for species-level identification.

Temporal and spatial insecticidal activities of three different transgenic cotton cultivars were evaluated: NuCOTN 33B cultivar expressing Cry1Ac insecticidal protein gene from Bacillus thuringiensis (Bt), developed by the Monsanto Company; GK12 expressing modified Cry1A Bt gene, developed in China; and SGK321 expressing both Bt and cowpea trypsin inhibitor (CpTI) genes, also developed in China. Two strains of cotton bollworm (CBW), Helicoverpa armigera (Hübner) with different susceptibility to Bt were used. Insecticidal activity in all three cultivars declined through time as plants grew,leaves had the highest insecticidal activity early in the growing season, but bolls and square showed higher insecticidal activity in the middle or late growing season. All three cultivars showed higher insecticidal effect against the susceptible strain of CBW than against the resistant strain of CBW. SGK321 had significantly higher insecticidal activity to CBW in the middle and late growing season (August and September), and also displayed more consistent resistance to the resistant strain of CBW compared to the other two cultivars.

Sequencing of the wsp gene in Wolbachia infecting mosquitoes of the Culex pipiens complex and Aedes albopictus was performed. The homology of nucletide and amino acids between strains infecting Cx. Pipiens complex and Ae. Albopictus in China and other strains of Pip group was 98%-100% and 97%-100% , respectively. The strains of Wolbachia which infect the Cx. Pipiens complex and Ae. Albopictus in China belong to the Pip group of the Wolbachia B-supergroup. These strains may induce cytoplasmic incompatibility in there hosts.

To determine the principal vectors of Lyme disease in North China, the capability of Dermacentor silvarum and D. nuttalli to transmit Lyme spirochetes transstadially was estimated under laboratory conditions. Spirochete\|free larval ticks were found to acquire Borrelia garinii if allowed to feed on infected KM mice. PCR tests indicated that 50% of such larvae subsequently became infected by B. garinii. However, cultivation revealed that only about 20.0% of these larva harbored live spirochetes. Spirochetes were detectable in D. silvarum and D. nuttalli larvae up to 8 days after ingestion but remained alive for only 2 days after ingestion. All engorged larvae no longer contained live spirochetes by the time they reached the nymph stage. PCR and cultivation indicated that both newly emerged nymphs and KM mice parasitised by these nymphs were negative for B. garinii. Spirochete-free nymph ticks could also acquire B. garinii by feeding on infected KM mice. PCR indicated that 50% of such nymphs became infected. Cultivation of spirochetes from engorged nymphs indicated infection rates of 33.3% and 60.0% respectively. Spirochetes were detectible for between 4 and 6 days but remained alive for only 2-3 days after ingestion. None of the engorged nymphs contained live spirochetes by the time they reached the adult stage. After molting, neither newly emerged adults or KM mice parasitized by them were found to be infected. The same tick species collected from different sites were similarly incapable of maintaining live Lyme spirochetes. We conclude that D. silvarum and D. nuttalli are unable to transmit infectious B. garinii to subsequent developmental stages. The presence of spirochetes in D. silvarum and D. nuttalli may be tied to co-feeding with Ixodes persulcatus.

Based on changes in nucleic acids and proteins during the development of Bombyx mori female accessory glands, it was determined that the protein content in these glands increased gradually from the sixth day after pupation to day of eclosion, peaking on the day of eclosion (860±70 μg/pair). The ratio of host Telenomus theophilae recognition kairomone to total protein varied significantly at different development stages, from 10% on the sixth day after pupation to 58% on the day of eclosion. The amount of total RNA increased from the sixth day after pupation to the day just before eclosion, but decreased quickly after eclosion. The quantity of RNA varied significantly between the secretory and reservoir portions. In the secretory portion, the amount of total RNA changed significantly during the development of the accessory glands. At its peak, the total RNA in the secretory portion accounted for more than 90% of the total RNA in the accessory glands. In contrast, the amount of total RNA in the reservoir portion was much less than that in the secretory portion and did not change significantly through development. The total RNA in the reservoir portion was only 1/10 as much as in the secretory portion on the day before eclosion. Agarose gel electrophoresis indicated that the quantity of 18S rRNA was much higher than that of 28S rRNA in the secretory portion. Certain sizes of extracted mRNA were relatively abundant, suggesting that these kinds of mRNA are specifically related to certain major secretory proteins.

Dengue fever (DF)/dengue haemorrhagic fever (DHF) is one of the most important human arbo-virus infectious diseases in tropical and subtropical areas with increasing numbers of patients and the expansion of epidemic areas. Understanding the mechanisms of its infection and spread is the foundation for effective surveillance and control of this disease and its mosquito vector. The saliva secreted by feeding mosquitoes is not only the liquid vector of virus transmission, but can also enhance virus infection through immuno-modulation of its vertebrate host.This paper reports experiments that sought to determine if the DEN-2 virus infection in Balb/C laboratory mice could be enhanced by the vector mosquito Aedes aegypti. After being bitten by a number of mosquitoes, mice were injected intravenously with defined titers of the DEN-2 virus. The differences in viremia, the titers of DEN-2 antibodies and the infection rates of macrophages in the abdominal cavities of these mice were observed and compared with those of mice that had only been injected with the DEN-2 virus. The results showed mice that had been bitten by vector mosquitoes were more easier infected with the DEN-2 virus; periods of viremia were extended from 1-2 days to 4 days, antibody titres dropped from 1∶64, 1∶96 to 1∶16 and 1∶32 respectively in the 4th and 7th days after injection while infection rates of macrophages varied over the first 7 days. These results indicate that vector mosquito bites can enhance the infection of mice with the DEN-2 virus.

The haemolymph ecdysteroid titres of the last instar and diapausing prepupa of the sawfly Chinolyda flagellicornis were determined by radioimmunoassy. The results showed that two peaks were present on the second and the fourth day of the last instar respectively. The haemolymph ecdysteroid titres of diapausing prepupa remained at a relatively high level (about 20 ng/mL). From about one week before pupation (the last instar) haemolymph ecdysteroid titres went up forming two separated peaks. It seems that the diapause of Chinolyda flagellicornis is regulated by ecdysteroids.

Individuals were selected for increased resistance to fenvalerate in the SRP (moderate resistance) strain and RP (high resistance) strain of Plutella xylostella, and in SRC and RSC strains of the parasitoid Cotesia plutellae. The SRC strain of C. plutellae was reared on a susceptible strain of P. xylostella larvae (SP), and the RSC strain was reared on SRP larvae. Selection for SRP, RP, SRC and RSC was carried out for 13, 14, 14 and 13 generations respectively. The SRP and RP strains of P. xylostella acquired 68.9 and 605.8 fold resistance, while the SRC and RSC strains of C. plutellae acquired 4.3- and 11.0-fold resistance, respectively. These results show that fenvalerate resistance by C. plutellae can be selected by applying the insecticide to host larvae harbouring the immature parasitoids. Moreover, the resistance level of the RSC strain was higher than that of the SRC strain, demonstrating that selection with more resistant hosts can accelerate the development of resistance in the parasitoid. Ratios of MFO activity in the SP, SRP and RP strains of P. xylostella were 1∶1.15∶1.50; ratios of MFO activity in larvae of the SC, SRC and RSC strains of C. plutellae were 1∶1.10∶1.49, and in the adults of the three strains of the parasitoid were 1∶1.18∶1.54, respectively. However, changes in the specific activities of CarE and Es in the different strains of each insect species did not show a similar trend to the resistance levels. These results indicate that fenvalerate resistance in C. plutellae is positively related to MFO activity, but unrelated to CarE and Es activity.

The co-toxicity co-efficiency (CTC) of a series of mixtures of abamectin as a biological pesticide, and chlorpyrifos as a phosphate insecticide with low toxicity to mammals, were determined with respect to the leafminer Liriomyza sativae. CTC of these mixtures was equal to 165-234 and within a range of marked synergism. According to the maximum and submaximum of proper proportions of chlorpyrifos to abamectin, two synergistically mixed, 30% permeated formulations, WP-1 and WP-2, were manufactured. Field trials showed that both compounds were highly effective in controlling L. sativae larvae. At an application rate of 50g/667 m², the corrected mortalities of WP-1 and WP-2 after 3, 7 and, 11 days were 90.43%-91.71% and 87.09%-90.53% respectively; at 25 g/667 m², the corresponding control effects of WP-1 were 85.96%-88.28%; and at 37.5g/667m², the corrected mortality of WP-2 was 84.01%-85.38%. These synergistic mixtures were fast acting, had good residual performance and were economical to use. In addition, 30% WP-1 was also effective in controlling L. huidobrensis. The advantage of using WP over EC is that less toxic substances are released into the environment.

One of the most efficient ways to obtain compounds with insecticide properties from traditional insecticidal plants is the extraction and isolation of minor secondary metabolites. Elliptone, isolated from the roots of Derris elliptica, is an active insecticide in the same chemical family as rotenone. Differences in toxicity, antifeedancy, inhibition of growth and development, and oviposition deterrence between elliptone and rotenone were evaluated with respect to imported cabbage worm (Pieris rapae), diamondback moth (Plutella xylostella), cabbage aphid(Brevicoryne brassicae), striped flea beetle (Phyllotreta vittata), and citrus red mite(Panonychus citri). The results showed that the toxicity of elliptone varied between species. Elliptone exhibited strong toxicity against citrus red mite, diamondback moth larvae, and adults of the striped flea beetle, but significantly lower toxicity against cabbage aphid and imported cabbage worm compared to rotenone (based on comparison of LC₅₀). Both elliptone and roteone displayed remarkable antifeedant activity. Elliptone, and to a lesser extent, rotenone, had some inhibitory effect on growth and development and deterred oviposition. Elliptone had a lesser inhibitory effect on NADHubiquinone oxidoreductase activity (50% inhibition ［IC₅₀］ at 5.27 nmol·mL-1) compared to rotenone (IC₅₀ at 2.58 nmol·mL^-1) which suggests that is a less effective respiratory inhibitor than the latter. Based on the data obtained in this investigation, it is possible that the higher toxicity of elliptone in leaf-disc immersion trials reflects its lower antifeedant activity and consequently higher ingestion rate.

The wasp Cotesia chilonis Munakata is one of the main larval parasitoids of the rice striped-stemborer, SSB, Chilo suppressalis(Walker). The behavioral responses of female Cotesia chilonis to volatile compounds emitted by these herbivores, rice or water-oat plants and herbivores damaged rice plants were studied with a Y-tube olfactometer. Female wasps were attracted to the volatiles from plants, stripedstemborer larvae and larval frass. Volatiles from herbivore damaged plants were more attractive to the female wasps than those from healthy plants. If larvae and larval frass were removed from damaged plants, these were no longer more attractive than mechanically damaged plants. However volatiles from herbivore damaged plants were also more attractive than healthy plants with larvae. This suggests that there is a synergy between volatiles from larvae damaged plants, larvae and/or larval frass. Rice plants that were damaged mechanically or/and treated with the larval regurgitant did not release attractive volatiles. The degree of attraction to volatiles from two varieties of seedlings, damaged plants, larvae fed on the two varieties of seedlings or their frass was not significantly different. These results indicate that the source of volatile compounds used by A. chilonis to locate its host habitat and host come from seedlings, larvae and larval frass, and more specifically, a combination of volatile compounds from plants, larva and/or frass.

The acetylcholinesterase (AChE) sensitivity and insecticide resistance of Plutella xylostella and its parasitoid, Apanteles plutellae Kurd.collected from Fuzhou, Fujian Province, were detected and monitored by bioassays and biochemical analyses. The results show that the AChE sensitivity of P.xylostella to six kinds of organophosphorus and carbamate insecticides increased gradually from September 1998 to April 1999, and that sensitivity of A. plutellae(collected from the corresponding hosts) showed the same trend. AChE sensitivity was higher in A.plutellae than in P. xylostella. After release from the selective pressure of the insecticides, both P. xylostella and A. plutellae displayed a rapid recovery in susceptibility to these insecticides and a significant increase in the K_i value of AChE. Insecticide resistance was associated with insensitivity to AChE in P. Xylostella and A. plutellae based on the kinetic parameters, K_m, V_max and the bimolecular rate constant K_i. This paper also profiles the K_i activity of AChE at different developmental stages of susceptible and resistant P. xylostella, and discusses the possible mechanism of AChE sensitivity in natural populations of both P.xylostella and A. plutellae.

Research was carried out on the structure and distribution of insect communities of Ficus auriculata in the tropical rainforest of Xishuangbanna. A total of 48 974 insect specimens representing 9 orders, 30 families, 56 genera, and 70 species were collected. The most important groups were families, genera and species of the Coleoptera, Lepidoptera, Homoptera, Diptera, Isoptera, Hemiptera, Neuroptera and Thysanoptera, of which the Coleopera and Homoptera displayed the greatest genus and species diversity. However, in terms of numbers of individuals collected the most important group was the Homoptera,which comprised 68.79% of the total. 56.58% of these were pollinating fig wasps. Fig wasps lay eggs or pollinate when female flowers are blooming, their offspring develop into adults until the male syconia are nearly mature. As far as the law of vertical distribution is concerned, species diversity and absolute numbers were greatest on the fruiting sites of old branches where 71.34% of all insects were collected. The next most important site was the crown and leaves where about 15% of specimens were found. 9.55% were found on the roots. Insects were least common on the branch axils and trunks where only 3.42% of all specimens were collected. Numbers of species and individuals varied in different seasons. The highest diversity and abundance was recorded in the rainy season (35.96%) followed by the dry season (34.22%) and the cool season (29.82%).

The lycosid spider, Pirata subpiraticus, is one of the major predators of rice planthoppers and other rice pests. Pitfall trapping indicated that a large number of these spiders move into rice fields from adjacent Zizania habitat after the transplantation of rice seedlings, most moving back to Zizania fields before the rice is harvested. Rubidium (Rb) mark-release tests indicated that the lycosid spiders could disperse up to 40 meters into rice field from a release site in a Zizania field, and suggest that Zizania fields are one of their refuges for overwintering. Direct marking of such predators with Rb is recommended as an effective tool for investigation of predator dispersal between habitats.

This paper revises the taxonomic status of Sportaphis sporta Zhang, 1999 and Polygonaphis aciculansucta Zhang, 1999 based on reexamination of the type materials specimens and additional materials. Four new junior synonyms are proposed: Sportaphis sporta Zhang, 1999=Tenuilongiaphis stata Zhang and Zhong, 1993; and Polygonaphis aciculansucta Zhang, 1999=Aspidaphis adjuvas (Walker, 1848); Sportaphis Zhang, 1999=Tenuilongiaphis Zhang, 1993; Polygonaphis Zhang, 1999=Aspidaphis Gillette, 1997. Specimens studied are deposited separately in the Zoological Museum, Institute of Zoology, Chinese Academy of Sciences, the Illinois Natural History Survey, University of Illinois and the France Natural History Museum, France.

Three new species of Tetrigidae from the Shennongjia area, Hubei Province are described: Tetrix shennongjiaensis sp. Nov., Tetrix lativertex sp. Nov. and Formosatettix hubeiensis sp. Nov. Type specimens are deposited in the Institute of Zoology, Shaanxi Normal University.

Jingicoris yunnanensis gen. Nov. et sp. Nov. was found and described from South China. The new genus, belonging to the tribe Phatnomatini, is allied to Pseudacalypta Péricart, Taphnoma Péricart and Exulmus Froeschner. Type specimens are deposited in Insect Collections of Nankai University, Tianjin, China.

All three known species of Apocolotois, A. arnoldiaria, A.smirnovi and A. almatensis are reported and their taxonomy revised in the present paper. A new junior synonym is stated: Chariaspilates shuangzhu Yang=A.smirnovi (Romanoff). A. almatensis is recorded as new to China. The genus characters are summarized and a key to the species is given. Illustrations of adults and genitalia are presented. The biogeographical features of the genus and included species are discussed.

The generic characters of Prosthiochaeta Enderlein (Diptera: Platystomatidae) are discussed. Three new species of the genus are described from central and southwestern China: P. emeishana sp. Nov., P. fuscipennis sp. Nov. and P. pictipennis sp. Nov. The illustrations of these new species and a key to known species of this genus are provided. All type specimens are deposited at the Institute of Zoology, Chinese Academy of Sciences, Beijing.

A new method had been developed to prepare the chromosomes of Eotetranychus kankitus Ehara and Panonychus citri (McGregor). It was found that the karyotype of Eotetranychus kankitus Ehara is n=4, 2n=8, and that of Panonychus citri is n=3, 2n=6 or n=4, 2n=8. The results of C-banding and scanning electromicroscope photographs indicated that chromosomes of these species were holokinetic. Mixoploidy was also discovered in the karyotypes of these mites.

Pheromones are an efficient tool in the prevention and treatment of termite infestations and have consequently been the focus of a considerable amount of research. In this paper we provide a brief description of termite pheromones and their analogues and summarize recent progress in research on these substances from both a chemical and biological perspective. Four key factors (the structure of pheromone molecules, the environment, experimental methods and pheromone concentration) affecting the activity of termite pheromones are discussed. Finally, we consider the recent developments in the literature to speculate on future directions for termite pheromone research.

Insects produce a variety of antibacterial peptides which act synergistically to kill invading microoganisms. Antibacterial peptides are also found in other animals. They are highly effective against becteria, fungi, viruses and protozoan parasites and also act as tumcides. With the number of antibacterial peptides increasing and their structure becoming known, some new mechanisms for their activity are proposed. With the aim of developing this field of research, we present a broad overview of the function, action mechanism, genetic engineering and clinical application of these substances.

Studies on insect antifreeze proteins have focused on several species, so far over twenty antifreeze proteins (AFPs) had been isolated. This paper reviews the present state of knowledge of antifreeze protein structure, composition, bioactivity, biosynthesis and the application of these substances. The secondary structure of AFPs is mainly β-sheet and turns and their most striking feature is the occurance of cysteines every six residues throughout their length. Almost all Cys residues are disulfide-bridged, which imposes significant structural constraints. Understanding the factors that affect AFP activity, such as activating proteins and low molecular solutes, is important for further progress in AFP research.

This paper reports a cDNA sequence and its deduced amino acid sequence in the late trypsin of Aedes aegypti Haikou strain. The cDNA fragment from the whole body of adult Aedes aegypti in 24 h after blood ingesting was amplified by RT-PCR and its specificity was confirmed by electrophoresis. The cDNA was inserted into pGEM T easy vector and transformed into E.coli JM109. The positive clone was sequenced by an automatic DNA sequencer. The cDNA and the deduced amino acid sequence were highly homologous with the late trypsin from the Aedes aegypti American strain, showing 98% and 99% similarity, respectively. The deduced amino acid sequence is highly homologous with those of other mosquitos' trypsins in both residues around the catalytic pocket and N-terminal sequences.

Tetranychus cinnabarinus (Boiduval), originating from Beibei, Chongqing, were continuously selected for resistance to fenpropathrin, abamectin and pyridaben. After 16 generations, resistance to fenpropathrin, abamectin and pyridaben had increased by 26.54-, 4.51-, and 1.16-fold, respectively. The realized heritability of resistance and resistance risk of T. cinnabarinus to these three acricides were evaluated using threshold trait analysis. The realized heritability of resistance to fenpropathrin, abamectin, and pyridaben was 0.2472, 0.1519, and 0.0160, respectively. Theoretically, to obtain a 10-fold increase in resistance requires 13-6 generations for fenpropathrin, 21-10 generations for abamectin, and 197-89 generations for pyridaben under selective pressure of 50%-90% mortality for each selective generation. Field populations would be expected to require more generations to obtain the same resistance levels. Of these three acaricides, the resistance risk was highest for fenpropathrin followed by abamectin and pyridaben. These results provide some basis for the management of pesticide resistance in T. cinnabarinus.

Genomic DNA were extracted and amplified using the polymerase chain reaction and arbitrary primers from specimens of seven insect species: Chrysomela vigintipunctata (Scopoli) (Coleptera: Chrycomelidae), Harmonia axyridis Pollas and Coccinella septempunctata Linnaeus (Coleoptera: Coccinellidae), Agrotis ypsilon (Rottemberg) (Lepidoptera: Noctuidae), Crocothemis servilia Drury (Odonata: Libellulidae), and Oxya abentata Willemse and O. chinensis (Thunberg) (Orthoptera: Catantopidae). Of the specimens assayed, some had been naturally dried, some oven-dried and the remainder had been preserved in alcohol. The results suggest that, with respect to DNA extraction, oven-dried specimens and those preserved in alchohol are better than naturally dried specimens. Extraction of DNA extraction using the CTAB method was easier, and more economical than other methods.

The forensically important fly Aldrichina grahami (Aldrich) was reared at constant temperature to study the chronology of parate adults within puparia. The results show that some morphological changes within the puparium can be used as age markers. The pupal stage of Aldrichina grahami can bedivided into seven developmental stages. The time required for pupal development was inversely proportional to temperature.

The morphology of female subgenital plate in grasshoppers is closely related to both copulation and oviposition. It is widely accepted that subgenital plate morphology is also informative in grasshopper taxonomy. In this paper, ten species belonging to six genera of Acrididae from China were selected, and their female subgenital plates examined after dissection from the body. The data were then used in a cladistic analysis. The results show that the characters of female subgenital plate are homologous and vary among different genera. The phylogeny of these six genera is (Carsula ((Phlaeoba, Gonista), (Phlaeobida (Gelastorhinus, Acrida))))，which is congruous with the cladistic results based on other morphological data, and in agreement with the viewpoint that the Leptacrinae be separated from Acrididae. The results also show the evolutionary directions of all 15 characters of female subgenital plates among the six genera.