Olfactory receptors in insects were found to be extremely diverse, but there is one exception. There is a kind of olfactory receptor, which shares a rather high identity among different insects. The gene encoding the similar olfactory receptor from Helicoverpa armigera was cloned and named as ORHarm. The ORHarm encoded 473 amino acid residues, including seven putative transmembrane domains, which is the typical characteristic of G protein-coupled receptors. ORHarm shares very obvious homology (>60%) with similar olfactory receptors reported from other insects and the homology with the close sibling species Heliothis virescens reaches 99.4%. Semi-quantitative RT-PCR analysis showed that ORHarm was highly expressed in antenna of H. armigera moth, low expressed in proboscis and not expressed in other tissues of the moth. ORHarm was also expressed in different developmental stages of egg, larva, pupa and imago. ORHarm may play important roles in sensing volatile odors as well as sensing liquid chemical stimulates.

With histochemistry techniques and image analysis of microscope photographs, the distribution and activity of fat and nonspecific esterase (n-E) in newly emerged and sucked adults of rat fleas, Monopsyllus anisus (Rothschild) and Leptopsylla segnis(Schönherr) were studied. The results indicated that in newly emerged fleas of the two species the fat was distributed mainly in fat body, while nonspecific esterase was distributed mainly in salivary glands and nerve chain. After blood meal and digestion, in M.anisus a great deal of fat drops appeared in the midgut and the fat drops decreased as digestion continued, and the activity of nonspecific esterase increased, but there was no significant difference in its activity in different digestion time; while in L. segnis, there was few fat drops in the midgut, and the activity of nonspecific esterase also increased, but its activity was lower than that in M.anisus in the same digestion time. During growing up of the oocytes, the fat drops and activity of nonspecific esterase increased, and the activity of nonspecific esterase in M.anisus was higher than that in L. segnis.

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The localization of Der p1 in the body of the house dust mite, Dermatophagoides pteronyssinus was studied. Der p1 antibody as primary antibody was prepared by immunizing the mice with Der p1 antigen. The fluorescent antimouse IgG antibody was used as secondary antibody. D. pteronyssinus was embedded in paraffin, sectioned, and then reacted with the primary and secondary antibody. The location of Der p1 in the body was observed with fluoroscope. Some sections were stained with HE staining. A large part of body cavity of D. pteronyssinus was occupied by the digestive system as shown with HE staining. The Der p1 allergen was mostly localized in the midgut and gut contents, while the cuticle and reproductive system showed negative reaction in the immunostaining.

The ultra-morphology and chemical composition of waxes secreted by the scale insects, Ceroplastes ceriferus (Fabricius) and C. japonicus Green (Homoptera: Coccidae) were studied with the techniques of scanning electron microscope (SEM) and gas chromatography/ mass spectrometry (GC/MS). The results indicate that the two wax scale insects have a similar waxy secretion and wax test forming process. The scale insects in their first and second instars secreted dry wax that formed a star-shaped test. Every wax horn around the margin of the test consists of two segments. This is corresponding to the two developmental instars. Furthermore, each of the two segments of the wax horn included many sub-segments. Meanwhile, the wax accumulated into a cap-like structure with many layers on the dorsal region of the body. It was believed that some kind of rhythm existed in the wax secreting. A lot of striate punctures formed wax glands that are usually unable to be found with the slide specimens of the wax scale insects observed under the light microscopy. As the scales developed into the 3rd instar and adult stage, the wax secretion changed into “wet state" and formed a waxy test in tortoise shell shape. The wax glands on the dorsal surface mainly are trilocular and quadrilocular pores. Dense wax pores arranging in longitudinal strips also were found over the anal plates. The main chemical compositions of the wax secretions of the two scale insects were determined with GC/MS by the two methods of esterification and unesterification. For C. ceriferus, 14 and 14 compounds were determined from its wax secretion with the two methods respectively; while 10 and 25 compounds were determined respectively from the wax secretion of C. japonicus. The main compositions of their wax secretions include a series of long chain saturated and unsaturated hydrocarbons, fatty acids, fatty alcohol, esters, and some compounds with ring structures of multi-, macro-, or heterocyclic ring. Their biological functions were discussed.

Cathepsin B from Helicoverpa armigera (HCB) plays important role in the life of the cotton bollworm, which degrades yolk proteins to amino acids as nutrients for embryonic development. Many plant seeds, such as soybean seeds and sunflower seeds, contain proteinase inhibitors. An inhibitor, HCB-SoyI, purified from the soybean seeds by ammonium sulfate precipitation, gel filtration and ion-exchange chromatography, was here reported. The inhibitory activity of the inhibitor was further studied with bovine albumin as a substrate. The purified inhibitor offers an opportunity to further clone its gene and may become a new target for insect resistant transgenic plant research.

The formation mechanism of the crystalline domain in Bombyx mori silk fibrion is just similar to that of α-synuclein (α-Syn), which is the pathogenic protein of human Parkinson's disease. That is to say, under the certain condition, a conservative sequence made of very hydrophobic amino acids and some random coils would cause the whole structure conversion and fibrillization of a protein. It had been found that the hydrophobic region of these two proteins was the key to the formation of β sheet. In order to study whether α-synuclein can be fibrillized after its aggregating core is replaced by another, we replaced the core region of α-Syn_1-74 (α-Syn₇₄) with the core region of B. mori silk fibrion using the PCR technique, and constituted a recombinant protein named as α-Syn₇₄SFX. After purification and incubation for 6 days, the structure of α-Syn₇₄SFX was examined with atomic force microscope (AFM) and ThT fluorescence. The results showed that fibrillization did not occur in α-Syn₇₄SFX. This suggests that the availability of a core region important to form β sheet and a random coil region does not necessarily make a protein to fibrillize. The research provided clues for the study of artificial silk.

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Whiteflies are plant sap-feeding insects that harbor prokaryotic symbionts, including primary and secondary endosymbionts. In this study, PCR-based detection of prokaryotic endosymbionts of a Bemisia tabaci B biotype and a non-B biotype China-ZHJ-1 population in Zhejiang, China was performed. Both B and non-B biotype populations harbored a common primary endosymbiont, but different secondary endosymbionts. A secondary endosymbiont of the family Enterobacteriaceae was detected in the B biotype population but not in the non-B biotype. Two other secondary endosymbionts, Wolbachia and Arsenophonus, were detected in non-B biotype population but not in B biotype. Phylogenetic analysis of primary endosymbionts based on 16S rDNA indicates that the non-B biotype is native to China while the B biotype is an invasive biotype.

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The influences of juvenile hormone analogues (JHA) on multiplication of Spodoptera litura nucleopolyhedrovirus were studied. The early 6th instar larvae of Spodoptera litura were infected with four concentrations of SpltNPV, 5×10⁶，1×10⁷，5×10⁷and 1×10⁸ PIBs/mL, respectively, and then treated with 10 μg methoprene (a JHA) per larva. The results indicated that the total virus yield of the four concentration treatments with virus and methoprene increased by 227.06%, 128.71%, 52.62% and 33.15% than that of the control with virus and acetone, the mean yield per larva increased by 49.15%, 48.40%, 36.40% and 31.11% and the mean mortality increased by 119.21%, 52.72%, 12.64% and 1.12%, respectively. The greatest virus yield was obtained when the larvae were infected by 1×10⁷ PIBs/mL and then treated with 10  μg methoprene per larva, and the total virus yield and the mean virus yield per larva were 1 701.8×10⁸ PIBs and 60.1×10⁸ PIBs respectively. The virus yield of every treated group was significantly greater than that of the control group. Furthermore, the effects of methoprene on digestive physiology of infected and non-infected host were also studied. The results showed that not only the life duration and food consumption of 6th instar larvae were increased, the food conversion efficiency and virus yield of the larvae treated with methoprene were also increased significantly.

To investigate the proliferation of Bombyx mori nucleopolyhedrovirus （BmNPV） in its host, the 5th instar larvae of the susceptible silkworm strain 306 were orally administered with determinate dose of BmNPV. After oral ingestion, midgut, haemolymph and fat body tissues were collected at different time to extract DNA. Fluorescence quantitative PCR amplification of BmNPV DNA polymerase gene （dnapol）was used to detect copy number of BmNPV, and each sample was normalized using silkworm cytoplasm actin A3. The results showed that BmNPV could be detected in the midgut 2 hours post infection.  BmNPV could be detected in the haemolymph and fat body 12 hours post infection. Through a latent period of 12 hours, rapid proliferation of virus was detected in the midgut, haemolymph and fat body. The proliferation of BmNPV entered a stationary phase 84 hours post infection.

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Celangulin Ⅳ and Ⅴ isolated from the root bark of the Chinese bittersweet, Celastrus angulatus Max. are the major active insecticidal ingredients of this plant. The mixed effects of celangulin Ⅳ and Ⅴ on insect neuromuscular excitatory junction potentials (EJPs) were studied by using the intracellular microelectrode recording on the ventral longitudinal body-wall muscle fibers of the 3rd instar larvae of Drosophila melanogaster. The results indicated that the effects of the mixture of celangulin Ⅳ and Ⅴ on EJPs of D. melanogasterlarvae, in which celangulin Ⅳ was in higher ratio, were same as that of celangulin Ⅳ. The blocking time of EJPs was delayed by the mixture of celangulin Ⅳ and Ⅴ, in which celangulinⅤ was in higher ratio. In conclusion, celangulin Ⅳ and Ⅴ could have different effects on glutamate potential of insect synapses.

Respiratory rates of 3－5 instar larvae of the susceptible strain (SS), near isogenic lines-resistant strain (NILs-RR), resistant strain (RR) ofthe beet armyworm, Spodoptera exigua (Hübner) to lambda-cyhalothrin were determined under the condition of 25±l℃, RH 70%， illumination 3 000 lx and photoperiod 14L∶10D. The results indicated that there were no significant differences in the respiratory rates of the same instar larvae among the three strains, and the increase of resistance level to lambda-cyhalothrin did not resulted in the change of the fundamental respiratory rate. Treated with lambda-cyhalothrin, all the larva respiratory rates of the three strains increased with the increase of treatment dose. However, the respiratory rate of the NILs-RR strain was higher than that of the RR strain, and both were higher than that of the SS strain under their respective LC₂₀ and LC₅₀ doses. The highest respiratory rate of the two resistant strains and the susceptible strain appeared at 5 h and 2 h after treatment, respectively. The high level periods of the respiratory rates in the two resistant strains were significantly longer than that of the susceptible strain. It would take 24 h and 15 h respectively for the resistant strain and the susceptible strain to recover to the initial levels of their respiratory rates. It was so inferred that correlation existed in some extent between the increasing rates of the respiratory rate and the ability of detoxification metabolism to lambda-cyhalothrin in S. exigua larvae after treatment.

The tannic acid is one of plant allelochemicals. In order to evaluate the potential of tannins in the larval control of noxious mosquitoes, the toxicity of tannic acid to 1st－4th instar larvae of the fenvalerateresistant and susceptible strains of Culex pipiens pallens was investigated in the laboratory, and the impact of tannins on the development of larvae was also observed. The results indicated that the larvae of the susceptible strain was more sensitive to tannins than that of the fenvalerateresistant strain, and the sensitivity of the former to tannins was 6.4, 4.9, 4.7 and 2.0 times as high as that of the latter for 1st－4th instar larvae, respectively. Among larvae of all instars of the two strains, the first instar larvae were always the most sensitive to tannins, while the third instar larvae appeared to be the most insensitive. In the solution of 1 000 mg/L tannins, the survival rate of larvae of the two strains declined with the rearing time. The survivors of larvae exposed to 100－500 mg/L tannic acid solutions had slower development than the control larvae in both strains, and the developmental duration from the first instar to pupation delayed 34.5－38.3 h for the susceptible strain and 59.2－93.4 h for the fenvalerate-resistant strain. Furthermore, the developmental duration of 1st－4th instar larvae were significantly different (P<0.05) between the control and the treatment when the concentration of tannic acid for the treatment was 125 mg/L in the susceptible strain and 250 mg/L in the fenvalerate-resistant strain. However, treating the first instar larvae of the two strains with 100－250 mg/L concentrations of tannic acid had no influence on the pupation, emergence and adult sex ratio of the survivors. The results suggested that tannic acid affected mainly the developmental duration of C. pipiens pallens larvae and the degree of influence was related to the susceptibility of larvae to fenvalerate. 

The linkage between inheritance of virulence and sex in the brown planthopper (BPH), Nilaparvata lugens (Stål) was studied based on two virulence indices,  honeydew excretion and weight gain. Virulence in three host related populations of BPH, which had been reared on rice variety TN1, Mudgo and ASD7 for 82 generations respectively, were studied with honeydew excretion and weight gain of female adult tested in 48 h. Virulence of BPH from avirulent BPH population (TN1 population, most individuals are avirulent), were significantly weaker than that from virulent BPH populations (Mudgo or ASD7 populations, most individuals are virulent). So, crosses and backcrosses were conducted between avirulent and virulent population to study the genetic model of virulence of BPH. In honeydew excretion testing, the results showed that the mean honeydew excretion of famale adults was significantly different in reciprocal cross populations (F₁ populations), which indicated that there were obvious differences in the virulence of these populations. The same result was obtained with the index of weight gain. The above results suggest that the inheritance of virulence of the brown planthopper may be sex-linked.

In order to explore the effects of transgenic Bt-cry1Ab corn pollen on the multicolored Asian lady beetle (MALB), Harmonia axyridis (Pallas), a series of experiments were conducted with a non-Bt isoline as the control in the laboratory. The H. axyridis beetles were fed with transgenic Bt-cry1Ab corn pollen mixed with a certain proportion of pea aphids Acyrthosiphon pisum (Harris) in the laboratory, and changes in their developmental duration and body weight at different stages were observed. The activity changes of three metabolic enzymes (α-naphthylacetate esterase, acetylcholinesterase and glutathione-S-transferase) in H. axyridis reared on transgenic Bt-cry1Ab corn pollen were also determined. Moreover, we monitored the sediment of Bt-Cry1Ab toxin protein in the bodies of H. axyridis by ELISA method. The results indicated that there was no marked difference in the developmental duration at each stage between these beetles fed on  transgenic Bt-cry1Ab corn pollen and those on non_Bt isoline corn pollen. The transgenic Bt-cry1Ab corn pollen also had no notable side effects on the body weight of H. axyridis  at different stages. The activities of metabolic enzyme activities in H. axyridis fed on transgenic Bt-cry1Ab corn pollen changed slightly compared with the control, which had no visible effect on the growth of H. axyridis. The sediment of Bt-Cry1Ab toxin protein in the bodies of H. axyridis at different developmental stages was so scarce that it could not been detected by ELISA method. It was concluded that there was no significantly harmful effect of transgenic Bt-cry1Ab corn on the growth and development of the beetle.

Trichogramma wasps reared on Antheraea pernyi eggs have been widely used throughout China as biological control agent against some pests. Cold storage facilitates more effective commercial rearing, transportation and inundative releases of Trichogramma spp. The effects of storage temperature (4℃, 7℃, 10℃ and 13℃), stage (egg, larva, prepupa and pupa) and period (2 weeks, 4 weeks, 6 weeks and 8 weeks) on Trichogramma dendrolimi reared on A. pernyi eggs were investigated by comparing the adult emergence rate, number of wasps per host egg and female ratio in different combinations of storage temperature, stage and period. The results showed these three factors of storage temperature, stage and period substantially influenced the adult emergence rate, number of wasps per host egg, but not the female ratio, separately or mutually. Among all storage temperatures tested, T. dendrolimi was most susceptive to 10℃, its emergence rate was greatly impacted at this temperature, and therefore 10℃ was considered to be unfavorable temperature for long-time storage. T. dendrolimi was not susceptive to 7℃ comparatively, which could be the favorable temperature for long-time storage. Favorable storage stage for long-term storage was different at different temperatures (4℃ and 7℃). Larva and pupa stages at 4℃ and egg and pupa stages at 7℃were found to be the most appropriate stages for cold storage, and in these combinations of storage temperature and stage less adverse effects on the adult emergence rate and number of wasps per host egg were found compared with other combinations of storage temperature and stage. Evaluated by the adult emergence rate, the optimal stage and temperature combination for cold storage of  T. dendrolimi reared on A.pernyi eggs was egg stage at 7℃; while evaluated by the number of wasps per host egg, the optimal combination was   pupa stage at 4℃ and 7℃.

The growth, development and reproduction of Trichophysetis cretacea (Butler) were studied at five temperatures (19℃, 23℃, 27℃, 31℃, and 35℃) in the laboratory. The results showed that the developmental rate of Trichophysetis cretacea increased with the rise of temperature from 19℃ to 31℃, and varied slightly at higher temperatures. The pupal stage was most sensitive to temperature change compared with other developmental stages, and all pupae died at 35℃. The generation survival rate was 87.1%, 83.0%, 85.2%, 70.1%, and 0% at above five temperatures respectively. The developmental threshold temperature required for egg, larva, prepupa, pupa and egg-adult was 9.08℃, 8.95℃, 7.80℃, 9.09℃, and 8.86℃, while the effective accumulated temperature was 62.4, 122.0, 16.0, 108.1, and 309.1 degree-day, respectively. Adult longevity shortened with the temperature increasing. The number of eggs laid per female was highest (91.3) at 27℃. At the temperatures of 19℃, 23℃，27℃, and 31℃, the net reproductive rate (R₀) of the laboratory population was 31.0, 41.8, 46.7, and 0.8, the intrinsic rate of natural increase (r_m) was 0.0813, 0.1439, 0.1710, and -0.0094, and the mean generation time was 42.2, 26.3, 23.1,  and 19.2 days, respectively.

The effect of the different liliaceous host plants on the growth, development and reproduction of Bradysia odoriphaga Yang et Zhang was studied by feeding its larvae with four host plants, Allium tuberosum, A. fistulosum, A. sativum and A. cepa respectively in the laboratory. The main chemical constituents of garlicin and alcohol extracts from A. sativum, A. cepa and A. tubersoum were analyzed using gas chromatography and mass spectrometry. The results demonstrated that the effect of four host plants on the growth, development and reproduction of Bradysia odoriphaga was different. The most favorable food in the four host plants for the growth, development and reproduction of the pest was A. tubersoum. When the larvae were fed with A. sativum and A. cepa, the death rate of the larvae increased, the larval stage prolonged, the pupal weight decreased, and the average fecundity reduced. The insecticidal activities of the alcohol extracts from A. sativum and A. cepa, and the synthetic garlicin against its first instar larvae were different. When the first instar larvae were treated with the alcohol extract (2 g dry powder/mL) from A. sativum and A. cepa, which was diluted 100 and 200 times, their corrected mortality after 48 hours was 54.7% and 28.0%, and 49.4% and 22.7%, respectively. However, when the first instar larvae were treated with 10% garlicin, which was diluted 500 and 1 000 times, their corrected mortality  after 48 hours was 100% and 80.0%, respectively. Chemical constituent analysis showed that thioether compound might be one of insecticidal substances in A. sativum and A. cepa.

The experiments were conducted to determine the transmission mode and rate of Spodoptera exigua nuclear polyhedrosis virus (SeNPV) from the infected parents to their progeny through feeding the 4th and 5th instar larvae with the concentrations of 2.8×10⁷ and 2.8×10⁶ PIBs·mL^-1 in the laboratory. The results showed that  SeNPV could be transmitted to the offspring by three modes, i.e. transovarian, transovum, and adult mating. The female-mediated vertical transmission test indicated that the adults developed from virus-infected larvae transmitted the virus to their progeny, resulting in 20％－48% mortality of the next generation (F₁) and decrease of the fecundity of F₁ progeny adults compared with untreated controls. Moreover, the experiment with surface of the egg sterilized by 5% formalin solution showed that SeNPV could be transmitted to larvae of F₁ generation by transovarian transmission, which caused 18.8% mortality of F₁ generation. The crossing experiments between virus-infected and non-infected females and  virus-infected and non-infected males indicated that virus could also be transmitted to F₁ generation by sperm of male adult, which caused 20％－40% mortality of offspring larvae. Furthermore, through the experiment of adult oral infection, it was found that SeNPV could also be transmitted to offspring at a prevalence rate of 28.6%.

Through regular and systematic surveys in five selected sampling plots of Phyllostachys heterocycla cv. pubescens forests managed with five different and typical measures respectively, including cultivation and fertilization, cultivation, weeding, spraying herbicide and non-management in Sanming of Fujian Province, China from 2001 to 2002, the effects of these measures on the composition and structure of arthropod community were studied. The results showed that in contrast with the non-management forest, the richness of the community decreased for the disturbances of the other four management measures. The missing species in the lower layer mainly belonged to Araneida, Hymenoptera, Hemiptera and Coleoptera, and those in the canopy mainly belonged to Hymenoptera and Coleoptera. Most of the missing species in the community were rare species (Pi<0.01). In the lower layer, due to the disturbances of cultivation and fertilization, cultivation and weeding, the individual number of the neutrals increased, but that of the predators decreased. In the canopy, the individual number of the predators increased, but that of the herbivores decreased due to the disturbances of cultivation and fertilization, cultivation, weeding and spraying herbicide. In general, the species diversity and evenness all decreased in the lower layer, but increased in the canopy due to the management disturbances. Among the four measures, spraying herbicide disturbed most slightly in the lower layer, and cultivation most slightly in the canopy. Moreover, long-term non-management and cultivation could benefit higher dominant degree of phytophagous mites, and long-term non-management, weeding and spraying herbicide could benefit higher dominant degree of Kuwanaspis vermiformis, and long-term cultivation and fertilization, cultivation and weeding could benefit higher dominant degree of Pantana phyllostachysae. This indicated that long-term management with single type of measures would result in outbreak of certain pests. It was so concluded that in the management of P. heterocycla cv. pubescens forest, it was necessary and important to manage with manifold measures alternately in different years.

The soil collembolas in the middle and west plains of Jilin province were investigated with the emphasis on such indices as individual density，number of groups，and community diversity，richness and evenness in relation to the types of land use, i.e., farm garden, farmland, Three-North Forest Shelterbelt, natural secondary forest and natural mowing pasture. The soil collembolas were extracted with Tullgren extractor and identified to the genus level with the aid of microscope. A total of 5 531 soil collembola individuals were captured, which fell into 2 sub-orders, 8 families, and 12 genera. Onychiurus, Folsomia, Acanthocyrtus, Xenylla and Coloburella were the dominant groups that accounted for 90.3% of the total individuals. A considerable difference in the number of individuals existed between the natural forest and other habitats affected by human activity. The collembolas were distributed evenly in different layers of soil profile in all habitats affected directly by humans for both samples collected in July and September, especially in July. In these habitats affected intensively by farming activity during the summer, more collembolas appeared in soil of the lower stratum. While the strong effects on the group richness were not observed in all habitats. These results suggested that the types of land use affected the species richness and abundance, and human activity had a significant impact on the soil collembola community. The characteristics of collembola community structures in different habitats were analyzed by using different indices, i.e., Shannon-Wiener Index, Marglef index and Pielou index. The agricultural activity reduced the collembola diversity. The difference of the collembolan community composition between the middle plain and the west plain of Jilin province was shown mainly by their difference in the dominant group density in all habitats.

Asecodes hispinarumBoucek, an important larval endoparasitoid of Brontispa longissima（Gestro）, was introduced into Hainan Province of China from Vietnam in March, 2004. The morphology, development, reproduction and reproductive potential of this wasp parasitoid were studied. The results showed that under the laboratory condition of 24℃±2℃ and RH 75%±10%, the mean developmental duration of egg, larva and pupa were 2.8 days, 6.7 days, and 7.5 days, respectively; the longevity of adults without nutritional supplement was 2.5 days on average. Both the temperature and nutritional supplement affected the longevity of adults, and the mean longevity of female adults was longer than that of male adults. Fecundity (per female) was 43 on average and the peak of oviposition occurred within 12 hours after mating. The functional response of A. hispinarum to 4th instar larvae of B. longissima belonged to Holling's type Ⅱ, and the parasitization efficiency of A. hispinarum decreased with the increasing of A. hispinarum density.

This paper provides a new taxonomic system for the Eurasian Oedipodidae, in which the 69 known genera are divided into 7 subfamilies including 3 new subfamilies: Locustinae, Oedipodinae, Heteropterninae subfam. n., Bryodeminae, Bryodemellinae, Oedipodacrinae subfam. n., and Rashidinae subfam. n.

The genus Mirollia was erected by Stål in 1873, with about 20 species recorded in the world, including 6 species from China. This paper described two new species from China, namely, Mirollia mutidentus sp. nov. and Mirollia bispina sp. nov. The type specimens are deposited in the Museum of Hebei University.

Insecticide resistance is one of the major obstacles that impede control of agriculturally and medically important arthropod pests. It is also an important manmade example of natural selection and evolution. Knowledge on insect resistance enable us not only to develop effective strategies for detecting, monitoring and managing resistance，but also to understand the rules of evolution of organisms. The molecular basis of insect resistance to many chemical insecticides has been elucidated in the past ten years. Target genes, mostly in the nervous system, have been identified and cloned from the fruitfly, Drosophila melanogaster，and resistance-associated mutations have been examined in a range of pest insects. More recently, with the advent of annotated insect genomes, resistance mediated by complex multi-gene enzyme systems such as esterases, cytochrome P450s and glutathione S-transferases has also been elucidated. The spread and evolutionary patterns of resistance genes have been revealed gradually. Additional resistance mechanisms will be found as the power of genomic technologies, such as the comparative genomics, microarray and positional cloning, is applied to further examples of resistance.

Peritrophic membrane (PM), composed of proteins, glycosaminoglycans and chitins, is an acellular structure secreted by midgut cells and lines along digestive tract in most insects. It is the first barrier and plays an important role in protecting the gut epithelium from infection of pathogens. Biocontrol-promoting factors, such as baculovirus enhancin, chitinase, calcofluor and agglutinin, can destroy PM's structure, vary its permeability and facilitate infection of pathogens to pest insects by binding with PM components specifically. In the current paper, enhancing activity and mechanism of each biocontrolpromoting factor were summarized and opportunities for the development of new midgut targeting strategies for control of pest insects were prospected.

Monochamus alternatus is the major vector of pinewood nematode disease，Bursaphelenchus xylopilus. Ten strains of Metarhizium anisopliae, of which six isolated from M. alternatus, and four from Anoplophora glabripennis, Pachynematus itoi, Galleria mellonella and a burrower bug (Cydnidae) at different locations, were tested for the sporogenous ability and spore germination rate. Three strains of M. anisopliae (1291, 1349, and 2049) were selected, and their virulences to M. alternatus and G. mellonella larvae were assayed using the adult-conidial attaching method (attaching all tarsi of adult with dry conidial) and larva dip method with Beauveria bassiana strain F-263 as the control. The results indicated that the three strains of M. anisopliae, especially the strain 2049, were highly virulent to M. alternatus, with the cadaver rates as high as 76.9%-93.1% (1×10⁷ conidia/mL) and 57.9%-75.0% (6.5×10⁵ -3.4×10⁶ conidia/individual) for larvae 15 d after inoculation and adults 20 d after inoculation respectively; as contrast, the cadaver rates by the B. bassiana strain F-263 was 96.3 % (1×10⁷ conidia/mL) and 55.0% (9.7×10⁵ conidia/individual) for adults and larvae, respectively. However, the virulence of the three strains of M. anisopliae to G. mellonella larvae was rather low, and this suggested that  they were strong　host specific. The three strains may serve as a potential source of biocontrol agents for M. alternatus.
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Twenty two BIPs (biparental progenies) generated from two bivoltine silkworm (Bombyx mori L.) hybrids, viz., SH^₆ × NB^₄D^₂ and CSR^₂×CSR^₄, were evaluated for their performance in seven metric traits (weight of 10 mature larvae, single cocoon weight, single shell weight, shell ratio (%), effective rate of rearing, yield/10 000 larvae (wt.) and filament length. The experiment was laid out in a completely randomized design (CRD) with three replications for each treatment. The aim was to short list promising progenies and to work out estimates of direct selection parameters like heritability and genetic advance so that the generated information is utilized for the formulation of effective breeding and selection procedures aimed at extraction of new and more productive genotypes. BIPs 2, 4, 5, 6, 7, 10, 14, 16, 19 and 20 displayed a significantly superior performance in several traits. Single cocoon weight, yield/10 000 larvae (wt.) and filament length exhibited moderate estimates of heritability and reasonable genetic gains indicating genotypic variability to be a major component of phenotypic variability; hence, scope exists to bring about improvement in these traits through simple phenotypic selection. The rest traits (weight of 10 mature larvae, single shell weight, shell ratio (%) and ERR) recorded moderate estimates of heritability and low genetic gains environmental variability to be a major component of phenotypic variability; hence, selection for these traits would be less effective.
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Antennal morphology and sensilla of the fire ants, Solenopsis invicta Buren (Hymenoptera: Formicidae) collected from Wuchuan, Guangdong and Nanning, Guangxi were observed by scanning electronmicroscopy. The antennae are sexually dimorphic: the female antenna is geniculate, and the male antenna wirelike. The worker antenna has 10 antennomers， with most sensilla distributed on the two distal segments (the antennal club). The queen antenna has 11 antennomers, with sensilla distributed on the three distal segments (the antennal club); whereas the clubless male antenna has 12 antennomers, with sensilla distributed on all segments. Seven types of sensilla were found on antennae of the female. They are sensillum trichodea, sensillum trichodea curvata, sensillum basiconica, sensillum coeloconica, sensillum ampullaceal, sensillum chaetica, and Böhm bristles. Most of these sensilla are on the female antennal club, except Böhm bristles which are located on the scape and pedicel. The male also have seven types of sensilla, while their distribution is different with that on the female. Böhm bristles are in the same distribution as on the female, but sensillum basiconica is distributed on the two distal segments, and sensillum ampullaceal is distributed on the three distal segments, and the rest four types of sensilla are distributed on each flagellum. An ultra-short sensillum trichodea was first found on males, which is absent on females and different from other known sensilla trichodea. The morphology and distribution of these sensilla were described, and their difference between castes and sexes was discussed.
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