In order to understand the inviability of hybrid F₁ eggs and the relationship of this to Wolbachia infection in the Culex pipiens complex in China, the crossing experiments of 4 subspecies of the complex without and with tetracycline treatment were performed. The results revealed there was unidirectional cytoplasmic incompatibility (CI) between Cx. Pipiens molestus males and females of the other 3 subspecies in the complex without tetracycline treatment, and the hatching rates of eggs from matings between the males of Cx. Pipiens molestus and the females of Cx. Pipiens pipiens, Cx. Pipiens quinquefasciatus and Cx. Pipiens pallens were 0.06%，0.46% and 0.19%, respectively. Treatment with tetracycline resulted in the elimination of CI. F₃ hatching rates after tetracycline treatment between the males of Cx. Pipiens molestus and the females of Cx. Pipiens pipiens, Cx. Pipiens quinquefasciatus and Cx. Pipiens pallens were 89.49%（t=3.90×10²⁸＜t_0.01=2.704），23.39%（t=9.15×10⁷＜t_0.01=2.660）and 22.27%（t=5.08×10⁴＜t_0.01=2.750）, respectively. However, treatment with tetracycline resulted in the occurrence of new kinds of CI.

Sequence analysis of the p35 gene of Hyphantria cunea nucleopolyhedrovirus (HycuNPV) showed that the HycuNPV p35 gene was 900 bp and encoded 299 amino acids. Compared with BomoNPV T3, AucaNPV, SpliNPV, LeseNPV and HearNPV, nucleotide and amino acid identity were 99.9%, 95.7%, 93.6%, 80.2%, 87.2% and 99.7%, 90.3%, 77%, 64.9%, 732% respectively, and showed evolutionary conservation. H¹²² of BomoNPV T3 p35 was replaced by R in HycuNPV p35. It is possible that the function and anti-apoptotic action of HycuNPV p35 is similar to that of BomoNPV T3 p35.

Galleria mellonellas were divided into four sections according to body color: dark, dark yellow, yellow, gray and white-yellow respectively. Through strict inbreeding of individuals with the same parents and body color, with the exception of the yellow group after eight generations the body color of offspring was the same as that of their parents. Thus, four strains were obtained: dark, dark yellow, gray and white-yellow respectively. Each strain was then crossed with the other strains (both positive cross and negative cross), and the F₁ selfed and backcrossed with their parents. The color of the F₁, F₂, B₁, P₁ and the number of larvae of each body in F₂ and B₁ were recorded. Analysis of these data showed that the heredity of body color in Galleria mellonella obeyed genetic regulations pertaining to autosome and multiple alleles. At least four multiple alleles affected body color. The dark yellow gene was dominant to the dark gene and the gray gene; the dark gene was incompletely dominant to the gray gene and the white-yellow gene, as was the gray gene to the white-yellow gene and the dark yellow gene to the whiteyellow gene. Individuals whose genotypes were AD, BD and CD were all yellow; those whose genotypes were AA or BC were dark yellow.

A strain of organophosphate (OP) resistant cotton aphid, Aphis gossypii was selected by exposure to omethoate insecticide in the laboratory. The resistance factor of this strain was 17 times that of an OP-susceptible strain of cotton aphid. Four substrates, α-naphthyl acetate (α-NA), α-naphthyl butyrate (α-NB), α-naphthyl phosphate (α-NP) and β-naphthyl phosphate (β-NP), were used to determine carboxylesterase activity, Michaelis constants (K_m) and maximum velocities (V_max) in OP-susceptible and resistant strains of cotton aphids. Carboxylesterase activity was significantly lower in the OP-resistant strain than the OP-susceptible strain when α-NA and β-NB were used as substrates and the same trends were obtained by native polyacrylamide gel electrophoresis (PAGE) analysis. However, no significant difference was found between OP-susceptible and resistant strains when α-NP and β-NP were used as substrates.

Insects use cellular and humoral immune systems to defend themselves from foreign bodies. We assayed the dynamics of plasma phenoloxidase (PO) activity in Helicoverpa armigera larvae after the injection of hydrophilic silica beads into the haemocoel, We also studied the effects of the activators trypsin and laminarin, and inhibitors p-NPGB and PTU on PO activities In plasma after silica beads were injected. The results showed that PO activities increased markedly after the injection of silica beads. PO activities in plasma were increased by the presence of trypsin, but under similar conditions PO activities did not follow the same trend when activated by laminarin. There may be an accumulation of prophenoloxidases (proPO) after the intrusion of foreign objects causing proPO to be activated at the appropriate time. P-NPGB and PTU can totally inhibit PO activities.

General esterase activity to α-NA in two susceptible laboratory strains (Yanshi and Hubei), two lab-selected resistant strains (PCP20 and YG45) and nine field strains of cotton bollworm Helicoverpa armigera Hübner were measured by microtiter plate kinetic assay. Frequency distribution patterns of esterase activity in the Yanshi, Hubei and Shawan susceptible field strains were similar and their mean esterase activities were 991, 1 138 and 1 055 mOD·min^-1·larva^-1 respectively. Two labselected resistant strains (PCP20, YG45) and three field resistant strains (Yanggu, Handan and Anyang) had many more individuals of high esterase activity (more than 1 800 mOD·min^-1·larva^-1) than three susceptible strains and their mean esterase activities ranged from 1 510 to 2 482 mOD·min^-1·larva^-1. Another two field strains (Xuzhou and Wuhan) had moderate-high easterase individuals and their mean esterase activities were 1 208 and 1 404 mOD·min^-1·larva^-1. The correlation coefficient between mean esterase activity and resistance level was 0.82 to pyrethroids and 0.42 to organophosphates. The same results were obtained when the correlation between the frequency of individuals with high esterase activity and the resistance levels to pyrethriod and organophosphate was analyzed. The results suggested that general esterase activity has some relationship to pyrethroid resistance levels. Because esterase is not a major mechanism for pyrethroid resistance in H. armigera it can only be used as a reference index for the detection of biochemical resistance.

A kind of trail pheromone analogue ((Z,Z)dodeca-3,6-dien-1-ol, DDE—OH) of the black-winged subterranean termite, Odontotermes formosanus Sharaki was synthesized. Active concentrations (10³-10 ng/cm) of this pheromone elicited similar behavior in worker termites as natural pheromone extract. There was no significant difference between the response of workers to synthetic and natural pheremones (P>0.05). When the concentration of synthetic analogue was higher than 10 ng/cm it had some repellent effect on termite individuals.

The protein concentrations of cell supernatants infected with recombinant AcNPV (Autographa californica nuclear polyhedrosis virus )containing wild type or mutant juvenile hormone esterase were between 153.32-188.0 μg/mL. The enzyme activity recovery rate was about 33%. The stepwise purification of the enzyme had similar results as the gradient method, but was more convenient for handling large volumes of cell supernatants. The cuticle blackening te st showed that the recombinant juvenile hormone esterase from Heliothis virescens had biological effects on tobacco horn moth larvae（Manduca sexta）.

Effects of a new type of nosteroidal ecdysone agonist W200013 on the fourth instar larvae of the cotton bollworm (Helicoverpa armigera) were studied by transmission electron microscopy. These observations revealed that W200013 initiated a precocious and lethal larval moult. At 6 h post treatment (pt), the deposition of additional layers of endocuticle, a dramatic increase in rough endoplasmic reticulum and a decrease in glycogen particles were noted in the epidermis. At 12 h pt, the ecdysial space had formed and epidermal cytoplasts appeared “frozen”. At 24 h pt, a double cuticle separated by the ecdysial space had formed and the epidermis was highly vacuolated. At 36 h pt, new epicuticle coated an incomplete new procuticle containing only a small number of lamellae, and the epidermis showed increasing signs of degeneration. As a result, the treated larvae died without normal ecdysis. At the same time, comparison with RH-5992 revealed that the two insect growth regulators produced similar toxic symptoms, bioassay results and ultrastructural changes of the integument.

The cotoxicity and coefficiency (CTC) of a mixture of abamectin as a biological pesticide and cyhalothrin as a chemical insecticide with low toxicity to mammals was determined with respect to Liriomyza sativae Blanchard. CTC of this mixture was equal to 161-232 in a range of marked synergism. According to the maximum of the proper proportion of cyhalothrin to abamectin, a 2% permeated WP synergistic formulation was manufactured. In the field trials the efficacy of this 2% WP against L. sativae larvae was excellent in both Shandong and Beijing districts. For example, at an application rate of 507g/667m2, corrected mortality in each zone after 3, 7 and 11 days was 85.26%-90.76% and 86.74%-94.02% respectively. At 25g/667m² the corresponding control effects were 75.28%-85.17% and 79.96%-88.68% respectively. This synergistic mixture was fast acting, had good residual performance and was relatively cost effective. Another advantage of using WP over EC pesticides is that a markedly less amount of chemicals are released into the environment, thereby decreasing pesticide pollution.

Mitochondrial cytochrome oxidaseⅠ(mt COⅠ) (～830 bp) gene sequences were utilized as markers to identify biotypes of 5 populations of Bemisia tabaci in China. Of the 720 characters examined for COⅠsequences, only 2 bases exhibited divergence and overall similarity was 99.7%. Examination of 423 characters in populations from Xi'an and Tulufan revealed that these two populations were of the same haplotype as AZB3. The results indicated that all 5 populations were of the B-biotype.

The green peach aphid, Myzus persicae (Sulzer), is an important pest of agricultural and horticultural crops. Its complex life cycle and genetics are the main factors influencing population outbreaks. The RAPD technique with 7 random primers was used to analyze DNA polymorphism in seven forms of M. persicae, which were: the mother of mating forms (alate), mating females (apterous), males (alate), eggs, the fundatrix (apterous), virginoparae (apterous) and virginoparae (alate). The results showed that eggs had the largest genetic variation, followed by the sexual forms with the parthenogenetic forms having the least amount of variation. There was a close genetic relationship between the fundatrix (apterous), virginoparae (apterous) and virginoparae (alate) in the green peach aphid.

Laboratory experiments were conducted to study the role of infochemicals from rice volatiles and rice planthoppers, and morphological characters of rice planthopper eggs, in host discrimination by the egg parasitoid, Anagrus nilaparvatae, between the brown rice planthopper (BPH), Nilaparvata lugens (Stal), and the whitebacked rice planthopper (WBPH), Sogatella furcifera (Horváth). The results indicated that there was no significant difference in attractiveness between BPH femaleinduced rice volatiles and WBPH female-induced rice volatiles, each of which attracted 57.50% (23) and 42.50% (17) of parasitoids tested, respectively. In a comparison of 4 types of BPH and WBPH materials, i.e., intact eggs, mashed eggs, plants with eggs and nymph-damaged plants, parasitoids showed no preference for any material except intact eggs, spending longer time on BPH eggs than on WBPH eggs. The headspace composition of BPH-infected rice plants was similar to that of WBPH-infected rice plants. The results suggest that infochemicals, kairomone from hosts and synomone from host-infected rice volatiles, and the morphological characters of eggs, do not mediate discrimination by the parasitoid between BPH and WBPH. The mechanism of host discrimination by the parasitoid between BPH and WBPH is discussed.

Effects of chemical control on diversity of insect pests and predatory natural enemy were investigated in 8 types of cotton fields in Raoyang County, Hebei Province in 1999. The results showed that chemical control affected diversity and homogeneity indices, richness and the numbers of pests and predators in different types of cotton fields. Chemical control had a more significant effect on the diversity of predator than pest communities. The effects of chemical control differed in different types of cotton fields and in different stages of the growing cycle: the effects were more prominent in cotton monocultures or cotton-bean intercropped fields than in those with cotton-wheat intercropping, in late sown than early sown fields, and in untilled fields than tilled fields. The effect was less on the edges of intercropped cotton fields than in the middle. The insect pest community was more sensitive to chemical insecticides at the early stage of the growing cycle, while chemical control significantly influenced the insect predator community throughout the growth period of cotton plants.

Composition and seasonal dynamics of litter-layer beetle community were investigated in the Dongling Mountain region (39°48'～40°02' N, 115°24'～115°36′E), 114 km to the west of Beijing, North China. Three areas containing 11 plots were selected to reflect the effects of vegetation, elevation and human disturbance on the beetle community. The first was Xiaolongmen, a lower-mountain area covered with well-protected woods, where 5 plots were surveyed, i. e. Pinus tabulaeformis plantation, Juglans mandshurica forest, Larix principis rupprechtii plantation, mixed deciduous broad-leaved forest and Quercus liaotungensis forest. The second was Liyuanling, an area of farmland abandoned 5 years ago and interspersed with some hills, where 3 plots were surveyed, i. e. Vitex negundo var. heterophylla shrubs, Prunus armeniaca var. ansu shrubs and Q. liaotungensis coppices. The third was an area of high elevation vegetation near the top of Dongling Mountain, where 3 plots were surveyed, i.e. Betula costata forest, Caragana jubata shrubs and meadows. The pitfall trap method was employed in this study. Field collections were made regularly, once each month during the growing seasons of 1999 and 2000.Of the beetles collected, the Carabidae, Staphylinidae, Chrysomelidea, Curculionidae, Tenebrionidae, Scarabaeidae and Elateridae were the dominant groups accounting for 83.36% of the total. Principal component analysis (PCA) and cluster analysis based on 40 dominant species collected in 1999 gave similar results: the 11 plots could be roughly categorized into three groups, i. e. the shrubs in Liyuanling, forests and coppices in Xiaolongmen and Liyuanling, and alpine vegetation near the top of Dongling Mountain. This indicates that vegetation, elevation, and human disturbance may be important factors influencing the distribution of litter-layer beetles in the Dongling Mountain region. The activity of adult beetles peaked in June and July in Xiaolongmen and Liyuanling, with variation in the dominant group between different plots. Daily catches of beetles were higher in the Xiaolongmen area, especially in Larix principis rupprechti plantation and mixed broad-leaved forest. The Carabidae and Staphylinidae were abundant groups in forest plots in Xiaolongmen and Q. liaotungensis coppices in Liyuanling, peaking in July. The Tenebrionidae abounded in June and occurred mainly in shrubs and coppices in Liyuanling, and in Juglans mandshurica forest and Pinus tabulaeformis plantation in Xiaolongmen. The Elateridae showed similar seasonal changes as the Tenebrionidae, but more individuals were captured in Larix principis rupprechtii plantation than in Pinus tabulaeformis plantation. The Chrysomelidae reached peak abundance in June or August in Q. liaotungensis forest and coppices, and in April or May in other forest plots in Xiaolongmen. Most of the Curculionidae appeared in May and August in Vitex negundo var. heterophylla shrubs, from May to July in Pinus tabulaeformis plantation, in June and July in Larix principis rupprechtii plantation, and Q. liaotungensis forest and coppices. The Scarabaeidae were abundant in July in Vitex negundo var.heterophylla shrubs, Larix principis rupprechtii plantation and Pinus tabulaeformis plantation, but in June in Prunus armeniaca var. ansu shrubs. Among the litter-layer beetles examined, the activity of predatory species lagged behind that of hytophages by about one month.

Five characters of the external male genitalia of 67 microgastrine species of 21 genera distributed in the Oriental and Palaearctic regions (including 14 genera known from China) and 2 species of Cardiochiles （as outgroup）were studied comparatively. Based on morphological studies, 34 characters including head, thorax, abdomen, female and male genitalia, and biological characters of 21 genera of 5 tribes were selected for cladistic analysis in an attempt to reassess the phylogenetic relationships among the tribes and genera of the Microgastrinae previously described by Mason (1981). The results generally supported Mason's framework of two main clades (Apantelini+Microgastrini) and (Forniciini+ Cotesiini+Microplitini) in the Microgastrinae. The tribes Apantelini, ForniciinI and Microplitini as monophyletic groups were also supported, but other two tribes, Microgastrini and Cotesiini, defined by Mason (1981) were not supported as monophyletic groups by the cladistic analysis. In conclusion, the tribes arranged by Mason (1981), although imperfect, are generally credible and applicable, and we consequently disagree with Walker et al.'s (1990) opinion that Mason's classification is not applicable.

This paper deals with the phylogenetic systematics of 11 genera of the tribe Blaptini (Coleoptera:Tenebrionidae) from China based on defensive gland structure. We summarized the characteristics of the glands at the generic level according to position, shape, length, width, distance between the two glands and surface fingerprint whorl, and used this information to compile a key to genera. The phylogenetic relationship of the 11 genera has been established using the HENNIG 86 program (version 1-5). The result shows the evolutionary route should be as follows: Blaptogonia > Prosodes> Thaumatoblaps> Blaps> Asidoblaps> Itagonia> Agnaptoria> Gnaptorina> Dila> Neoblaps> Coelocnemodes. All specimens are deposited in the Museum of Hebei University.

This paper deals with 4 species of Mimopydna Matsumura, 1924 from China. M. cuspidata Wu et Fang is described as new to science. M. sikkima stueningi Schintlmeister is synnonymized with M. sikkima sikkima (Moore). The male and female genitalia are illustrated. A key to the Chinese species is provided.

Cytoplasmic polyhedrosis viruses (CPVs) (Reoviridae: Cypovirus) are icosahedral particles with a segmented double-stranded RNA genome. CPVs were divided into at least 15 distinct electrophoretypes on the basis of variations in the electrophoretic migration patterns of the genome segments. Attempts to define the evolutionary relationships and origins of cypoviruses have been hampered by the lack of enough genetic information. This is mainly due to the fact that the various methods used in the past for sequencing dsRNA genomes are technically difficult, time consuming and require large amounts of viral RNA. Among CPVs, complete nucleotide sequences of genome dsRNA segments have already been reported for two type 1 CPVs from Bombyx mori (strains I and H ) and Lymantria dispar, respectively, a type 14 CPV from Lymantria dispar, and a type 15 CPV from Trichoplusia ni.

Aggregation pheromones are important semiochemicals in insects that play a key role in mating and other social behavior. Many chemicals, including hydrocarbons, alcohols, aldehydes, ketones, esters, acids, anhydrides, amines, and nitriles, have been identified as insect aggregation pheromones, however, understanding of their potential utility in pest management is still limited. Aggregation pheromones have been found in eggs, larvae and adults, however, some volatiles from host plants have been regarded as pheromone components. Aggregation pheromones of the same species in different stages of the life-cycle can be distinct, and the same semiochemical may induce different behavior in different developmental stages or physical states. Nevertheless, the aggregation of insects can be regulated by semiochemicals such as kairomone, sex pheromone and alarm pheromone. Understanding of insect aggregation pheromones is still inadequate and determining the precise function of these chemicals requires further research.

Females of many insect species mate repeatedly during their lifetime and have the ability to store sperm from different mating males in sperm storage organs. As a result, sperm from different males compete to fertilize one female's eggs. Males display strategies for assessing female maternal quality, predicting future sperm competition risk, sperm heteromorphism and prolonged mating behavior. Females display strategies for assessing male paternal quality and the active manipulation of ejaculates to give precedence to different male sperm. These strategies reflect the influence of both natural and sexual selection.

A cysteine proteinase from cotton bollworm eggs was purified by anion-exchange chromatography based on previous work. The proteinase gave a single band after SDS-PAGE. The molecular mass of the purified proteinase was estimated to be 29 kD, which showed proteolytic activity in an in situ hydrolysis experiment. A partial amino acid sequence was compared with that of other typical proteinases. Similarities were appreciable between the composition of the egg proteinase and cysteine proteinases, particularly cathepsin B.

A preliminary study of the structural activity and relationship between EBF and its derivatives was conducted by comparing the structure of the aphid alarm pheromone (EBF) with its fluoro derivatives using computer molecular fitting. This demonstrated that these derivatives, which are substituted by one, two or three fluorine molecules in the conjugated diene of EBF, are similar to EBF in structure. They could possibly be active in bioassay.

The effect of diet and density on the fecundity of adult houseflies in the pilot scale production of housefly larva was studiedA diet of brown sugar and milk powder was found to increase the fecundity of adult houseflies, and vegetable juice was found to be a helpful additiveThe fecundity was maximal （9.68 ovum/ind·d） at a moderate adult density（5.973 ind/m³）. The greater the adult density，the more stable the fecundity and the higher the total ovum number in the experimental enclosure. The peak of fecundity was reached about four days after oviposition began and was maintained for 3-5 days. A week later the fecundity had decreased markedly. After the oviposition peak had passed，the present population was killed，and another population already at the peak of oviposition was introduced. The fecundity was maintained continuously at a high level，which is an important aspect in artificial rearing

Coccophagus yoshidae Nakayama is an important parasitic wasp of Chloropulvinaria polygonata (Cockerell). The parasitic wasp has 6-7 generations per year in Yaan and overwinters as young larvae and pupae in the 2nd and 3th instar larvae of its host. The thermal threshold and thermal sum for development are 8.40℃and 453.09 day-degrees respectively. The mean generation times at 18℃, 21℃, 24℃, 27℃ and 30℃ were 44.60 d, 38.27 d, 30.83 d, 23.73 d and 20.73 d respectively. The adult wasp sucks host body fluid for its complementary nutrition. The parasite is thelyotokous. Maximum emergence occurred at 8:00-12:00 every day, between the third and the sixth day. The longevity and offspring number per adult wasp were related to temperature and complementary nutrition. The wasp prefers to lay eggs first on adult females and then on the 2nd, 3th instar larvae of Its host.