To identify immune-related genes in housefly (Musca domestica) larvae, suppression subtractive hybridization (SSH) was performed to generate a subtracted cDNA library between bacteria-challenged (Escherichia coli and Staphylococcus aureus mixture) housefly larvae (Tester) and control housefly larvae (Driver) using the PCRSelect^TM cDNA Subtraction Kit according to the manufacturer’s protocol. The subtracted target cDNAs were ligated into the pGEM-T-Easy vector using T4 DNA ligase and transformed into E.coli DH5α competent cells. Positive white clones were randomly selected and sequenced after PCR detection. PCR analysis showed that the white bacteria clones contained inserts of 200-1 000 bp. The sequences inserted were used to search GenBank with BLASTX. A series of ESTs of 36 kinds of proteins including antibacterial peptides, enzymes, ribosome proteins and other functional proteins as well as unknown proteins, were isolated from 161 clones sequenced randomly. RT-PCR analysis revealed that two differentially expressed genes, defensin gene and attacin gene, were up-regulated in housefly larvae challenged for 24 h, while the genes encoding other proteins like lysozyme 1, prophenoloxidase activating factor, chymotrypsin and eukaryotic translation initiation factor were first down-regulated in housefly larvae challenged for 0-4 h and then up-regulated at 12 h post treatment. These results have established a solid foundation for cloning immune-relevant genes from M. domestica and further studying immune mechanism in housefly.

The superfamily of cysteine protease inhibitor consists of proteins which can inhibit the hydrolytic activity of cysteine proteinases. In this study, MdCPI, a gene of cysteine protease inhibitor was cloned from housefly (Musca domestica)by RACE based on dbEST information. It contains a 357 bp open reading frame encoding 118 amino acid residues. The deduced peptide contains a putative signal peptide of 17 amino acids. The amino acid sequence of MdCPI showed the highest homology with that of Sarcophaga crassipalpis  (identity=51%) in the homologous assay. The phylogenetic tree indicates that the CPIs from housefly and other dipterans have descended from a single common ancestor and belong to I25A family. To understand the inhibitory activity of MdCPI to cysteine protease, a prokaryotic expression vector pET-17b-MdCPI was constructed and then expressed in Escherichia coli BL21. The results of activity detection showed that about 1 μg recombinant MdCPI could inhibit the activity of 14 μg papain. The results suggest that MdCPI is the member of the CPI supperfamily, and may have similar functions and be involved in immunological and physiological regulation. The successful cloning, expression and activity detection of MdCPI provided a basis for the further study on its function.

In order to study the distribution of heavy metals in wolf spider Pirata subpiraticus and their effect on activities of antioxidant enzymes, 50 soil samples and 300 individuals of P.. subpiraticus were collected from five different habitats in Nanyang City, Henan Province in June 2009. The contents of heavy metals (Cd, Pb, Cu and Zn), GSH level, and GST, CAT and SOD activities in different body parts of P. subpiraticus were measured using atomic absorption spectrometry. The results showed that the contents of Cd, Cu and Zn in P. subpiraticus were significantly different between four heavy metal polluted habitats  (TBJK, TBTK, NYYT, and NYJG) and the control habitat (BTM, a nature reserve with less heavy metal pollution)(P<0.05), and also significantly different among different body parts in the same site (P<0.05), whereas the rank order was cephalothorax>legs>abdomen. Contents of Cd, Cu and Zn in the male were significantly higher than those in the female (P<0.05). The higher the content of heavy metals, the higher the GSH level. Moreover, the GSH level in the male was significantly higher than that in the female (P<0.05). In different body parts, the highest GSH level was found in the cephalothorax, followed by legs and abdomen. GSH level and heavy metal content correlated positively (r²=0.854, P<0.05), while significant negative correlations existed between heavy metal content (Cd and Pb or Pb) and activities of antioxidant enzymes. The enzyme activities in the male were significantly lower than those in the female. In the same site activities of antioxidant enzymes were not significantly different among different body parts. Therefore, the degree of heavy metal pollution can be known through testing the activity change of antioxidant enzymes of P. subpiraticus, and this wolf spider can be used as a very important bio-indicator for heavy metals pollution.  

Understanding copulation behavior of chalcids can help the development of techniques for manipulating chalcid behavior, and thereby increase the efficacy of chalcids as biological control agents in insect pest management. The effect of compound eyes and antennae on copulation behavior of Tetrastichus brontispae Ferrière was studied by smearing its compound eyes and antennae with water-soluble melanin pigment and liquid paraffin, respectively The ultrastructure of compound eye and sensilla on antenna of T. brontispae was observed with scanning electron microscope (SEM), and the differences of distribution and quantity of sensilla on antenna of two sexes were analyzed. The results showed that there was a significant difference in the role of the compound eye of the chalcid in copulation behavior between two sexes. The importance of every segment to copulation of male chalcid decreased in the order of antennal scape, antennal club, and antennal flagellum, but for the female the order was antennal flagellum, antennal club, and antennal scape. Eight distinct types of the sensilla were found on antenna with scanning electron microscope. As the major sensilla, both sensillum trichodeum and sensillum placodeum were distributed widely on the antenna. Moreover, there was an obvious sexual dimorphism of antenna of the chalcid as shown by different size of the antenna and different shape, size, number and distribution of the sensilla.

The unique sex pheromone components were employed by insects in order to achieve their intraspecific communication and interspecific reproductive isolation. However, the trace differences in the isomers of sex pheromone components can affect their biological activity extensively. The monounsaturated pheromone components of major insect pests were methylthiolated with dimethyldisulfide (DMDS) and analyzed by capillary gas chromatography (GC)-electron impact (EI) mass spectrometry (MS) in order to determine the double bond position in the aliphatic monounsaturated chain with alcohol, aldehyde or acetate functional groups. GC-EI-MS analyses of the resulting DMDS adducts of pheromone components with alcohol or acetate functional groups showed simple mass spectra with recognizable molecular ions and two high intensity diagnostic ions at m/z 61+14m ［H-(CH₂)_m-CH=S⁺ CH₃］ and 77+14n［CH₃S⁺ =CH(CH₂)_nOH］(or 119+14n，［CH₃S⁺ =CH(CH₂)_nOOCCH₃］)indicating the original double bond position in the aliphatic chain. Although the DMDS adducts of monounsaturated aldehydes also produced the molecular ions of the derivatives and a series of key fragment ions, this can not allow an immediate determination of the position of the double bond in the original unsaturated compounds by low-resolution EI-MS since the nominal mass of a carbonyl group is the same as that of two methylene groups. The location of the double-bond position using the DMDS adducts and GC-EI-MS methods is simple, time efficient, and highly sensitive, and this procedure shows a good prospect in sex-pheromone identification.

To determine the species of the yeast-like symbiont (YLS) in the rice planthoppers, the YLS was first isolated and purified by ultracentrifugation from the fat bodies of the small brown planthopper, Laodelphax striatellus (Fallén), and then 18S rDNA and 5.8S-ITS rDNA sequences of the YLS were amplified with the general primers for fungi. Sequence homology analysis showed that 18S rDNA and 5.8S-ITS rDNA obtained were different from the strain that Noda et al. had identified previously, but showed high homology (99.8%) with those of Pichia guilliermondii. The results of in situ hybridization (ISH) and nested PCR proved that this kind of Pichia-like symbiont existed in the body of L. striatellus and involved in the transovarial transmission. The results suggest that there exist other YLS in L. striatellus besides the kind of YLS identified by Noda et al.

PCR amplification of 16S rDNA with universal primers was conducted to detect the symbiotic bacteria of the rice brown planthopper, Nilaparvata lugens (Stål) . Analysis of the sequences showed that the brown planthoppers contain the symbiotic bacteria Arsenophonus，which has close relationship with Arsenophonus symbiont of Psyllidae and Aleyrodidae based on phylogenetic analyses. Two 16S rDNA sequences of Arsenophonus in N. lugens with different sizes were amplified, one is 1 504 bp and the other is 547 bp in length. The shorter one is the deleted product of the longer one by loss of its internal region of 957 bp. With two primers redesigned based on the above 16S rDNA sequences, the result of PCR amplification showed that the two different fragments existed in various host-associated populations and different geographic populations of N. lugens. Using 23S rDNA specific primers, the genus Arsenophonus was found in all the tested populations of N. lugens, but not in the host rice plant. The TN1 population carried significantly higher amount of Arsenophonus bacteria than the Mudgo population and ASD7 population assessed by quantitative real-time PCR. This is the first report of Arsenophonus bacteria from N. lugens.  

Mineral oils with high quality are seeing more recognition in modern pest management approaches and internationally accepted for use in organic farming as pesticides. Mineral oils are mixtures including a lot of components，and their components and proportion determined physical and chemical properties and pest control effect. The equivalent Normal-paraffin carbon numbers (nCy) and carbon number distribution of four mineral oils (SK EnSpray99, Caltex Lovis Miscible Summer Oil, Ampol D-C-Tron Spray oil, and Citrole paraffin oil)  (hereinafter referred to as SK, Caltex, Ampol and Citrole oil, respectively) and six molecular distillation fractions (＜120℃, ＞120℃, ＜105℃, 105－120℃ fractions of Caltex oil, and ＜110℃ and ＞110℃ fractions of SK oil)  were determined and the oviposition repellent effects of their 0.5% aqueous emulsions against the oriental fruit fly, Bactrocera dorsalis, were bioassayed by dipping treatment in the laboratory. The results showed that the average puncture numbers of B. dorsalis on banana treated with SK, Caltex, Ampol, Citrole oil and water were 17.850±1.282, 3.400±0.630, 15.850±1.439, 20.650±1.212, 19.050±1.155, respectively, and those on starfruit were 15.500±3.969, 3.000±0.707, 13.750±4.131, 17.250±4.385, 62.000±4.708, respectively, and those on banana treated with 6 molecular distillation fractions were 4.400±1.166, 8.200±0.583, 5.400±1.720, 2.400±1.077, 4.800±1.594, 12.200±2.63, respectively. There was significant difference in oviposition repellency against B. dorsalis among mineral oils (P<0.05), and nCy of mineral oils with the best repellent effect was nC23 or so. Correlation analysis of Spearman’s rank correlation coefficient (Spearman’s rho) test between carbon number distribution and oviposition repellency of mineral oils showed that there was a significant positive correlation between the repellent effect and the content of C23 of mineral oils (P<0.05). The results would be helpful to further research the repellent components of mineral oils against pests and the repellent mechanism.

To clear the mechanism of activity differences of azadirachtin A and azadirachtin B, the toxicities of azadirachtin A and azadirachtin B on Trichoplusia ni BTI-Tn-5B1-4 cell line were compared. The results showed that both azadirachtin A and azadirachtin B had excellent inhibitory effect on BTI-Tn-5B1-4 cell proliferation. After T. ni BTI-Tn-5B1-4 cells were treated with azadirachtin A and azadirachtin B for 3 d, their IC50 values were 2.09 μg/mL and 9.85 μg/mL, respectively, suggesting that the toxicity of azadirachtin A was greater than that of azadirachtin B. Under inverted microscope, it was found that both azadirachtin A and azadirachtin B could induce cell deformation, adhesion capacity reduction and vacuole appearance, and azadirachtin A showed obviously greater effect than azadirachtin B. Azadirachtin treated-cells were commonly bigger than the control, and the cells treated with azadirachtin A were bigger than those with azadirachtin B through flow cytometry analysis. Azadirachtin can also change membrane potential of BTI-Tn-5B1-4 cells After BTI-Tn-5B1-4 cells were treated for 3 d, DiBAC₄ (3) fluorescence intensity in azadirachtin A and azadirachtin B-treated cells was 88.12% and 55.37%, respectively, showing that azadirachtin A had greater effect than azadirachtin B. Under fluorescence microscope, it was found that azadirachtin could influence cell nucleus, and azadirachtin B affected more remarkably than azadirachtin A, based on the results that the amount of cells with damaged-nucleus treated with azadirachtin B was larger, and damage in cell nucleus was more severe. The results suggest that there exists mechanism difference between azadirachtin A and azadirachtin B, and provide the clues to explain the mechanism of azadirachtin that inhibits insect growth at the cell level.

 In order to explore the induced resistance of wolfberry by exogenous jasmonic acid and the influence on insects, in the laboratory at 25℃ three concentrations of jasmonic acid (JA) and the control (acetone and distilled water at the ratio of 1∶599) were used to spray seedlings of wolfberry Lycium barbarum Linn., which were used to rear the wolfberry aphid Aphis sp., and then the developmental duration, body weight and fecundity of these aphids were tested. The results showed that the developmental duration, adult longevity, fecundity and body weight were significantly influenced on JA-induced wolfberry seedlings and the influence was related to the JA concentration. The longest nymphal period was observed on 0.01 mmol/L JA-induced seedlings, which was 4.93 d, 1.9 d longer than that of control. The adult fecundity was reduced significantly, and the higher the concentration of JA solution, the lower the fecundity of the adult. Nineteen less nymphs produced per adult on the 0.1 mmol/L JA-induced seedlings than on the control seedlings. The adult longevity on the induced seedlings was about 3 d shorter than that on control. The daily body weight began to be influenced significantly on the 3rd day post JA treatment. On the 5th day post JA treatment, the average body weight was 0.395 mg for aphids on the control, and only 0.211 mg for aphids on 0.01 mmol/L JA-induced seedlings, and the range of body weight difference between aphids on JA-induced and control seedlings was 0.128-0.184 mg.

Massicus raddei (Blessig) (Coleoptera: Cerambycidae) is an important wood-boring insect pest infested Quercus spp. in northeastern China. To explore the biological control approaches, parasitism of a recent described species of parasitoid, Sclerodermus pupariae Yang et Yao, on the 1st-2nd instar larvae of M. raddei was determined. The results showed that the number of killed young larvae of the longhorn beetle significantly increased along with the increase of host densities during the parasitoid adults’ feeding on hosts for supplementary nutrition. The functional response could be described by Holling type Ⅱ model, with the average maximum 0.53 host individuals killed per day. The functional response for parasitism fitted Holling type Ⅰ equation, with the upper limit of host density of 4 larvae per tube during a searching time of 21 days. When the parasitoid density was fixed as one wasp per test tube, the searching efficiencies for both killing action and parasitism on young larvae of M. raddei decreased along with the increase of host densities. When the host density was fixed, along with the increase of host densities the number of host individuals killed increased linearly and the number of parasitized host individuals also increased, whereas the searching efficiencies for both killing action and parasitism of the parasitoid on the young larvae of M. raddei decreased significantly. These findings may serve as reference for rational evaluation on the ability of S. pupariae against the pest in fields and establishment of technical criterions for natural enemy release in forests.  

The brown planthopper, Nilaparvata lugens, is a major rice pest in many parts of Asia. Insecticides have been extensively used for its control, and resistance to various insecticides in this species has been reported in different countries and areas. The resistance to imidacloprid, a neonicotinoid insecticide, in N. lugens had caused big loss in rice production in recent years. Meantime, great progresses have been achieved in its imidacloprid resistance mechanisms and nicotinic acetylcholine receptors (nAChRs), the target of neonicotinoid insecticides. NAChR is an important neurotransmitter receptor in insect central nervous system, which makes it become the important target to several kinds of insecticides, including neonicotinoid insecticides extensively used to control N. lugens in recent years. The Y151S mutation had been identified in two N. lugens nAChRs α subunits, Nlα1 and Nlα3, which have distinct influence on imidacloprid affinity, but little influence on acetylcholine. Nlα1, Nlα2 and Nlβ1 are co-assembled into one receptor, which constitutes the lower affinity binding site for imidacloprid in N. lugens, while Nlα3, Nlα8 and Nlβ1 are co-ssembled into another receptor, which constitutes the higher affinity binding site. Imidacloprid resistance was found not only related to insect nAChRs, but also influenced by insect nAChRs accessory protein, such as lynx proteins in N. lugens, the insect nAChRs modulators. Most achievements mentioned here were newly reported, and are important to understand the resistance mechanisms to neonicotinoid insecticides and the pharmacological properties of insect nAChRs.  

Hox genes play an important role in the mechanism of developmental regulation of insect body plan and the expression of Hox genes shows strict tissue specificity and the programming of embryonic development. The silkworm, Bombyx mori, is a good representative insect of the order Lepidoptera. The Hox genes have been identified one after another in the silkworm. There is a complex loci of pseudoallelic genes in the silkworm called E complex and its mutant phenotypes are related with the extra markings or the supernumerary legs in the abdominal segments, which may have a close relationship with Hox genes. After the completion of sequencing for the silkworm genome it was found that there are 12 homeobox genes(Bmshx1~Bmshx12) specific for the silkworm in the Hox genes, which shows a unique biological significance of Hox genes. We have analyzed the spatial expression profile of Bmlab and Bmpb in the silkworm based on the B. mori microarray data. Through the research on Hox genes and the mechanism of the establishment of silkworm body plan, it is expected that it may found a theoretical basis for the body plan of other Lepidoptera insects. We reviewed the expression and function of Hox genes and their relationship with E mutants in this article.  

Studying on the selective preferences of Apolygus lucorum and Adelphocoris suturalis (Hemiptera: Miridae) to cotton plants with different resistance levels and damaging treatments could help us establish a theoretical basis for IPM of cotton bugs. In this study, we used plants of the resistant variety BR-S-10 and the susceptible variety Kelin 08-15 and the plants of these two cotton varieties damaged by A. lucorum and A.suturalis bugs respectively as tested materials, and fresh air as the blank control, and a total of fifteen pair combinations of source odor were formed to investigate the taxis responses of A. lucorum and A. suturalis to cotton plants with different resistance levels and damaging treatments with Y-shaped olfactometer in the laboratory. The results indicated that the selective preferences of A. lucorum were in the order of the susceptible variety, the susceptible variety damaged by A. suturalis and the susceptible variety damaged by A. lucorum, sequentially. However, A. suturalis preferred to the susceptible variety damaged by A. lucorum, the susceptible variety damaged by A. suturalis and the susceptible variety observably. In general, two mirid species tended to significantly choose the susceptible cotton varieties, and showed an aversion to the resistant cotton plants. A. lucorum tended to choose the susceptible variety damaged by A. suturalis and the susceptible variety damaged by A. lucorum, while A. suturalis preferred to the susceptible variety damaged by A. lucorum and the susceptible variety damaged by A. suturalis.  

To study the major features of the spatio-temporal variation in the diversity of grassland grasshopper in different grassland types in the northern slopes of Qilian Mountains, four grassland types were selected and sweep-net method was used to investigate the richness and relative abundance of grassland grasshoppers from June to October in 2008 and 2009. In total 28 species (or subspecies) belonging to 7 families and 15 genera were collected. Average species richness ranged from 7 to 23 species per grassland type. The species richness was lower in the alpine shrubland, and there were only 7 and 8 species in 2008 and 2009, respectively. The species richness was higher in the alpine grassland in 2008 (16 species) and 2009 (23 species). Species richness of the desert grassland and the alpine meadow was between the two mentioned above, and there were 15 and 15 species in 2008, and 9 and 12 species in 2009, respectively. The results suggest that spatial heterogeneity determined by moisture, thermal resource, vegetation and geographical factors plays an important role in determining community composition, diversity and special distributions of grassland grasshoppers.

The population dynamics and life history of European sunflower moth, Homoeosoma nebulellum Denis et Schiffermüller (Lepidoptera: Pyralidae), a serious pest of cultivated sunflower in China were investigated in Bayannur (41.06°N, 107.24°E), Inner Mongolia from 2008 to 2009 to develop a sound forecast and management program. The results indicated that the sunflower, Helianthus annuus L.，Garland chrysanthemum, Chrysanthemum coronarium Mill.，common cephalanoplos, Cephalanoplos segetum (Bge.) Kitam.， and common sowthistle, Sonchus brachyotus DC. in the family Asteraceae are host plants for H. nebulellum in this district. S. brachyotus is a newly recorded host plant species for this pest in China. Two generations occurred annually in the field of this district as investigated by sex pheromone traps and filed surveys. The overwintering larvae began pupating in late April, then emerged in mid-May, but at this time they are still not able to oviposit due to the absence of blossoming host plants. Larvae in the first generation damaged sunflower blossoming in late July although they could also attack C. coronarium blossomed in late June. Majority of the matured larvae in the first generation pupated and emerged after late July, but 9.2% of them enter diapause for hibernation. Larvae in the second generation damaged sunflower blossoming after mid-August. Most larvae began burrowing into soil for hibernation after mid-September, but there were still 30% of larvae that could not mature when sunflowers were harvested. The immature larvae were transferred into impurities of sunflower seeds for overwintering. Under temperature of 24℃, RH 70% and photoperiod of L16∶D8, the mean developmental duration of egg, larva, and pupa was 4.2, 15.9 and 11.1 d, respectively, and longevity of male and female adults was 14.9 and 15.1 d, respectively. An annual life history table for the H. nebulellum in Bayannur was drawn based on the observed data.

The invasive species Echinothrips americanus Morgan, 1913 (Thysanoptera: Thripidae) was recently found in Beijing, China. Both morphological and molecular methods were used to identify this species. External morphology of different stages was observed and recorded under stereo microscope. A 430 bp segment of mitochondrial COⅠ gene was amplified and sequenced from this species for molecular identification. Based on all coding positions and 1st and 2nd coding positions of mitochondrial COⅠ genes, the phylogenetic tree of the newly found species together with other 38 thripid species was constructed. The tree based on matrix composed of 1st and 2nd coding positions using NJ method could resolve the identification of thripid species better than that composed of all codon positions using other methods. This method provides an easy way to detect the dispersal of this species in other areas. Finally, biological characteristics of this thrips and the control measures were discussed.