Trehalose-6-phosphate synthase (TPS) is a key enzyme in trehalose synthesis pathway of insects. This research aims to clarify the important significance of TPS in the process of energy synthesis and against high and low temperature environment, and further understand the molecular mechanism of diapauses in the onion maggot, Delia antiqua, through the cloning, bioinformatic analysis and diapauserelated expression profiling of TPS. Based on an EST fragment from the suppression subtractive hybridization library of D. antiqua, TPS gene specific primers were designed, and its cDNA was cloned by RACE method and designated as DaTPS1 (GenBank accession no. JX681124). The full-length cDNA of DaTPS1 is 2 904 bp in length with an opening reading frame (ORF) of 2 488 bp encoding 815 amino acids. The calculated molecular weight of the predicted protein DaTPS1 is 91.2 kDa, with an estimated pI 5.96. Homology searching showed that DaTPS1 has two conserved domains, and shares the highest amino acid sequence identity (92.1%) with TPS1 from Drosophila melanogaster. The predicted three dimensional structure of DaTPS1 consists of 15 big alpha helices and 11 anti-parallel β-strands. RT-PCR analysis showed that DaTPS1 was expressed in non-, summer- and winter-diapausing pupae. The expression level of DaTPS1 in different developmental stages of non-diapausing pupae was relatively stable. However, its expression was lifted in the prediapause stage, declined in the diapause stage, and then up-regulated in the post-diapause stage of both summer- and winter-diapausing pupae. The increased trehalose synthesis trigged by TPS1 in the prediapause stage of summer- and winter-diapausing pupae suggests an increase in resistance to environmental stresses during diapause development, and that the declined metabolism in the diapause stage results in the decrease in energy need so the expression of TPS1 is down-regulated in the stage. However, the growth and development at the postdiapause stage recover gradually and the energy need increases, so the expression of TPS1 is up-regulated again. The study has significance in understanding the role of TPS of insects in trehalose synthesis pathway and the molecular mechanism of insect diapause.

Aquaporin (AQP) is a vital transmembrane protein participated in water recycling, desiccation resistance and cold hardiness in insects through the transportation of some neutral small molecules. In order to research the molecular characterization and spatial and temporal expression of AQP genes in Spodoptera litura, two full-length transcript variants of aquaporin 1 (AQP1) gene were cloned from S. litura by RT-PCR and RACE technology and named SL-AQP1A (GenBank accession number: KC999953) and SL-AQP1B (GenBank accession number: KC999954), respectively. There is a continuous 81 bp deletion in the 5′ open reading frame tail end of SL-AQP1B compared to that of SL-AQP1A; other sections of the sequences, however, are the same between the two genes. The deduced amino acid sequences of SL-AQP1A and SL-AQP1B are highly conserved among Lepidoptera species. Both of the two proteins have six full transmembrane domains, two semi-transmembrane domains, two conservative NPA (asparagine-proline-alanine) motifs, and the ar/R (aromatic arginine) selectivity filter based on topology and three dimensional predictions. Real time quantitative PCR results showed that there were obvious differences in the overall expression level of SL-AQP1 in the detected samples, and  moreover SL-AQP1B had a higher relative expression level than SL-AQP1A. SL-AQP1 was expressed at high levels in the egg and pre-pupal stages, and in such tissues as the hemolymph, midgut, Malpighian tubules and salivary glands, suggesting that SL-AQP1 play key roles in the osmoregulation and embryonic development and metamorphosis of S. litura. The results provide some molecular proofs for the physiological effect of SL-AQP1 in S. litura.

The lustrous (lu) and varnished eye (ve) are recessive single-gene mutants in the silkworm, Bombyx mori. So far, the mechanisms of the mutation and mutant genes are unknown. Using the wild-type strain Dazao (Dz) as the wild-type control, we observed the surface morphology of adult compound eyes and larval ocelli in lu and ve by optical microscopy and scanning electron microscopy, and the internal structures with paraffin sections and HE staining technology. The results showed that the surface morphology of the compound eyes in lu and ve except the typical characteristic of luster are significantly different from the normal, including the shape and size, and the shape, arrangement and quantities of ommatidia in lu and ve are also different from the control. The cornea, crystalline cone, rhabdom and pigment cell structures are abnormal, but not the same in lu and ve. Not only the surface of compound eyes has changed, but their internal structure has varied largely in lu and ve. This study provides helpful data for cloning mutant genes from lu and ve and clarifying the mechanisms of the mutations.

The ovarian structure as well as oogenesis is closely related with the accurate forecast of the pest occurrence peak and the appropriate control time. In order to make sense of the ovarian structure and oogenesis in the cotton bollworm, Helicoverpa armigera, we investigated both the ovarian structure and oogenesis of H. armigera female moth under the light microscopy and transmission electron microscopy, and determine the grading criteria to divide different developmental stages. According to the morphological characteristics of ovaries, the formation of eggs in the lateral oviducts and the characteristics of yolk deposition, the H. armigera ovaries are graded into 6 stages, including stage 0 (the initial stage), stage Ⅰ (yolk deposition prophase), stage Ⅱ (yolk deposition phase), stage Ⅲ (egg maturation phase), stage Ⅳ (peak phase of oviposition) and stage V (terminal phase of oviposition). According to the ultra-structural change of the oocytes and follicular cells, the developmental period of oogenesis is divided into 3 stages: the vitellogenesis prophase, vitellogenesis stage and yolk maturation stage. This study is the first research about oogenesis of H. armigera using electron microscopy, which optimizes the grading criteria of ovarian development of the cotton bollworm. The result provides an important theoretical basis for further study of reproductive development of H. armigera, and also has important practical meaning for the accurate forecast of outbreak date and scale in pest management.

【Aim】 This study aims to determine the geographical differences in the components and relative contents of venomous alkaloids in the red imported fire ant, Solenopsis invicta, from two invaded areas. 【Methods】 Workers of S. invicta were collected from USA and South China, and then extracted with HPLC grade hexane followed by GC-MS analysis. The chemical identity of GC peaks was identified and their relative percentage content was obtained. 【Results】 The cis alkaloids and trans alkaloids from body extract of fire ant workers could be readily separated by silica gel column chromatography. By using GC-MS technique, 7 cis alkaloids, 8 piperideines, and 7 trans alkaloids were identified from alkaloid fractions of fire ant colonies collected in the invaded areas of USA and China. The relative percentage contents of these components were different in different degrees between the USA populations and the South China populations. 【Conclusion】 The chemistry of venom alkaloids of the red imported fire ant between USA and China is quite similar. Only S. invicta is found in China, suggesting that S. richteri and hybrid fire ants may have not invaded China yet.

【Aim】 This study aims to further reveal genotypic polymorphism of Spodoptera litura nucleopolyhedrovirus (SpltNPV) in the wild based on genome sequences. 【Methods】 The virus clones A5, F1, X3 and X15 were isolated from SpltNPV Egypt stock, Fukuyama stock and Ogasawara stock by in vivo cloning technique, respectively. According to the complete genome sequence of SpltNPV (GenBank accession no.: NC_003102) and some SpliNPV gene sequences (GenBank accession no.: X99377, X99376 and X98924), primers were designed. Polyhedrin and ORF18-ORF23 of A5, F1, X3 and X15 were obtained by PCR amplification. 【Results】 According to the polyhedrin sequence, A5 and F1 belong to SpliNPV type, while X3 and X15 belong to SpltNPV type. The homologous comparisons of ORF18-ORF23 were done between A5, F1, X3, X15 and SpltNPV or SpliNPV. The results showed that F1 shares high nucleotide identity with SpliNPV, and X3 shares high nucleotide identity with SpltNPV, but only 387 bp is deleted at 172-558 nt of ORF20. Though X15 belongs to SpltNPV type according to the polyhedrin sequence, ORF18-ORF23 all share high nucleotide identities to those of SpliNPV, and as a SpltNPV-unique ORF, ORF22 is deleted in X15 genome. A5 belongs to SpliNPV type, and the corresponding ORF18-ORF20 share high nucleotide identities with SpliNPV, but ORF21 shares 100% nucleotide identity with that of SpltNPV. As a SpltNPVunique ORF, ORF22, however, appears in A5 genome, and shares 100% nucleotide identity with that of SpltNPV. Furthermore, ORF23 shares high nucleotide identity with that of SpliNPV. 【Conclusion】 These results indicate that SpltNPV in the wild possesses genotypic polymorphisms, and moreover, the genomes of these virus clones with the same genotype have significant differences. The natural heterogeneity can be exploited to develop NPV strains suitable for the control of S. litura.

Chemical control is the main method to control mosquitoes that are the primary vectors of human diseases. Previous resistance investigations showed that mosquitoes in China had become resistant to organophosphates, organochlorines, carbamates and pyrethroids. There are two main resistance mechanisms, i.e., the target resistance and the metabolism resistance that three detoxification enzyme families are involved in. An insecticide-susceptible strain is indispensable for resistance monitoring and studies of resistance mechanisms. In this study, we established an insecticide-susceptible strain of Culex pipiens quinquefasciatus from a field population by screening the isofemale lines without the G119S mutation in the acetylcholinesterase and with the low activity of carboxylesterases, P450 monooxygenases, and glutathione-S-transferases. Compared to another susceptible strain, S-lab, the strain screened here had 1.5-old higher carboxylesterase activity and equivalent P450 and glutathione-S-transferase activities. Insecticide bioassay showed that this strain had a less than 2-fold resistance to organophosphates and no resistance to carbamates and pyrethroids compared to the S-lab. Therefore this strain can be applied as an insecticide-susceptible strain in resistance monitoring.

Experiments in the laboratory were conducted by continuously observing the larva-translocation behavior during maternal care in an ectoparasitoid Sclerodermus guani, with the goal of determining the developmental stage of offspring when larva-translocation behavior is initiated and exploring the rhythm of the behavior. Tenebrio militor pupae aged less than 24 hours were used as the host. The parasitoid larvae were divided into four groups according to their developmental maturity, i.e., young larva (1st-2nd instar), old larva (3rd-4th instar), mature larva (naturally dislodged) and spinning larva (starting spinning cocoon after dislodged). Parasitoid larvae treated were dislodged artificially (for young larvae) or naturally (for old larvae) from the host. A female wasp was continuously recorded for larva-translocation behaviors using video camera, and then analyzed by playbacks. The results showed that the female wasp patted larvae of all stages with its antennae, but did not move the young larva. The female exhibited a strong tendency to move the mature larva, with an instant probability of 4.09 times as high as that to move the old larva. The instant probability of moving the spinning larva was 7.69 times as high as that of moving the old larva. The proportion of larvae moved was 96% for the old larva and 100% for both mature and spinning larvae, without a significant difference between them (P≥0.05). The time the female parasitoid spent on a larva-translocation was on average 27.96 s for the old larva, 34.04 s for the mature larva, and 32.49 s for the spinning larva, without significant differences between them (P≥0.05). The larva-translocation distance, the direct length by which a larva was moved, was 4.19, 7.18, and 9.43 mm for the old, mature, and spinning larva, respectively; there was no significant difference between the first two (P≥0.05), but there was between the first two and the last (P<0.05). The linear trend analysis showed that there was a significant decreasing trend in the number of larvae tapped before translocation, but not in the larva-translocation duration and distance. There was a significant autocorrelation at lag 1 and 2 in the number of larvae tapped before translocation, and at lag 1 in the larva-translocation duration, but not in the larva-translocation distance. The results of this study suggest that S. guani females do not initiate larva-translocation behavior until their offspring larvae mature, and some behaviors of larva-translocation may be rhythmic.

In order to investigate the relationship between nutrient accumulation and distribution in plant organs and alfalfa resistance to thrips, changes in N, P, K and Ca contents in alfalfa organs of the resistant (R-1) and susceptible (I-1) strains to thrips were measured after alfalfa plants were infested by Odontothrips loti. The results showed that the N contents in R-1 and I-1 stems increased significantly while those in R-1 and I-1 leaves decreased significantly (P<0.05), the N content in I-1 roots decreased firstly and then increased while that in R-1 roots decreased all the time. The P content in R-1 stems increased firstly, and then decreased, and the changes in P content in I-1 stems were insignificant. The P content in R-1 leaves increased constantly under the lower density stress, and then decreased when alfalfa plants were infested by 7 adults/branch, while that in I-1 leaves decreased significantly. The P contents in R-1 and I-1 roots were significantly higher than that of the control significantly (P<0.05). The K contents in R-1 and I-1 increased firstly and then decreased both in leaves and stems, whereas that in roots decreased (P<0.05). The Ca contents in R-1 stems and leaves increased significantly after infestation (P<0.05), the changes in Ca content in roots were insignificant compared with the control. The Ca content in I-1 stems decreased firstly and then increased, that in leaves was significantly lower than that of the control when leaves were damaged by 7 adults/ branch, and that in roots was significantly lower than that of the control. Overall, the levels of essential elements in alfalfa under O. loti infestation varied with alfalfa variety, the damage index of R-1 was significantly lower than that of I-1 (P<0.01), and R-1 showed stronger insect resistance.

The study aims to investigate the structural characteristics of Diptera mitochondrial genomes and design universal primers for sequencing of Diptera mitochondrial genomes so as to establish an overall framework of information for further study of Diptera mitochondrial genomes. We analyzed the structural characteristics, base composition and conserved regions of dipteran mitochondrial genome based on the known 26 fulllength mitochondrial genome sequences of Diptera using comparative genomics and bioinformatics methods, and designed a set of universal primers for mitochondrial genome sequencing of Diptera. The results show that the mitochondrial genomes of Diptera are 14 503-19 517 bp in length, and their structure are quite conservative with 37 coding genes, including 13 protein-coding genes, 22 tRNA genes and two rRNA coding genes. In addition, there is a non-coding region (AT-rich region) with various lengths. The individual gene location order on these genomes is quite stable, consistent with that on the mitochondrial genome of Drosophila melanogaster with only a few exceptions. The base composition on these genomes is not balanced with the AT content (72.59%-85.15%) significantly higher than the GC content, and base usage bias exists with A (50.91% of AT content) and C (57.79% of GC content) base usage significantly higher than T and G. We identified 11 conservative regions based on the nucleotide and amino acid sequence conservation analysis of whole genome, and designed 26 pairs of universal primers for mitochondrial genome sequencing of Diptera with each pair of primers anchored to identify conservative regions. The target fragment amplified with each pair of primers is less than 1 200 bp in length. This set of primers was applied for sequencing Delia antiqua mitochondrial genome, and the results prove that the set of primers is efficient and operable.

Up to now, the reports about the complete mitochondrial genome of katydids and their corresponding molecular evolution are still limited. In this study, the mitochondrial genomes (mitogenome) of two longlegged katydids, i.e., Mecopoda elongata and M. niponensis, were sequenced using the LPCR combined with the sub-PCR technology. The results showed that the mitogenome sequence of M. elongata is 15 284 bp in length, haboring the A+T content of 71.8% (GenBank accession no.: JQ917910), while M. niponensis is 15 364 bp in length with the A+T content of 72.4% (GenBank accession no.: JQ917909). The differences in their mitogenome sizes can account for the size variations in their control regions (294 bp for M. elongata and 393 bp for M. niponensis). The organization and gene content of both two Mecopoda mitogenomes are identical with those of other studied Tettigoniidae species. A few of noteworthy larger non-coding regions are shared by both species: the first is between trnA and trnR (63 bp in M. elongata, and 68 bp in M. niponensis), the second between trnQ and trnM (55 bp in M. elongata, and 26 bp in M. niponensis), and the third between trnS^UCN and nad1 (21 bp in both species). In both Mecopoda species, there are overlaps between trnC/trnW (8 bp), atp8/atp6 (7 bp) and nad4L/nad4L (7 bp). AT nucleotide composition bias of both Mecopoda mitogenomes is also reflected in the codon usage of NNU or NNA bias. In both Mecopoda mitogenomes, all protein-coding genes (PCGs) start with the typical ATN initiator codon expcept for nad1 and nad2 with TTG and cox1 with ATGA. All tRNAs in both Mecopoda species have the typical clover leaf structure except for trnS^AGN. Some unmatched base pairs occur in both Mecopoda species, and overwhelming majority of them are G-U pairs, indicating that G-U is a normal base-pairing model in insect mitogenomes. Another unusual feature is the relatively lower A+T content of control region (CR) compared with other regions of the mitogenomes, underlining the fact that high A+T content is not characteristic of this control region. The results of this study provide some valuable molecular data for clarifying the intra-subfamilies phylogenetic relationship in Tettigoniidae.

Termites are the oldest social insects in the world, and their sociality is maintained by pheromone communication. In this article, the new research progress on termite pheromones in recent years, including trail pheromone, sex pheromone, alarm pheromone and phagostimulating pheromone, is reviewed. The chemical components of the pheromone-producing exocrine glands of termites and their functions are summarized. Termite pheromones are mainly secreted by the tergal gland, sternal gland, posterior sternal gland, frontal gland and labial gland. Most of termite pheromones are volatile substances. Available data indicate a strategy of pheromonal parsimony in the chemistry communication of termites, i.e., the same compound is sometimes secreted by different glands of different species and may have different functions. The similarities/differences in chemical complexity and function of these pheromones between species and between the castes or sexes of the same species are summarized. The activity threshold, optimal concentration, longevity and speciesspecificity of the pheromones that affect pheromone functions are also introduced. At present, researches of termite pheromones are still in the initial stage. The research results are of great significance for Isoptera phylogeny and termite control. Finally, pheromones to be used in termite control are prospected.

 Diglyphus wasps are important bio-control agents for agromyzid leafminer, and have been studied and applied widely all over the world. In view that the agromyzid leafminers on vegetables, especially the invasive species, have rapidly spread and caused serious damage in China, the knowledge on the species, distribution, the occurrence and ecological dominance of this parasitoid in the field, as well as its control characteristics, biological and ecological adaptability, and field application, will provide important guidance for the biocontrol of the agromyzid leafminers. All Diglyphus species are idiobiont ecto-parasitoids, and 36 species have been identified up to now. The dominant species and the species that have been studied extensively include D. isaea, D. begini, D. intermedius, etc. This parasitoid causes the death of host larvae not only by reproductive host-killing by parasitizing but also by non-reproductive host-killing by feeding on or stinging without feeding and oviposition. The females prefer to parasitize the hosts with large size but feed on the host larvae with relatively small size, and the preference of female parasitoids to host larvae shows the host-size-dependent sex allocation behavior. Of the Diglyphus species, D. isaea has the widest temperature adaption and control potential against the agromyzid leafminer. The mass-rearing of the dominant parasitoid has been developed and widely used in the field, showing good control effect. We propose that the future researches on this parasitoid can focus on the following aspects: (1) the researches on the dominant species especially the populations or strains with wide temperature adaption or heat resistance, so as to increase the control effect on Liriomyza trifolii and L. sativae; (2) the researches on the feeding behavior and physiology mechanism of females for more efficient application; (3) the development of the mass-rearing and releasing techniques of this parasitoid according to different regions; (4) the researches on the cooperative control, and the competiveness and coexistence mechanism of this parasitoid with other parasitoids of agromyzid leafminer, so as to enhance the biocontrol effect on the agromyzid leafminer.

【Aim】 In order to clarify the resistance mechanism of Tetranychus urticae to spirodiclofen at the molecular level. 【Methods】 The full-length cDNAs of GST genes of T. urticae were cloned by RT-PCR, the structure and function of the coded proteins were analyzed by bioinformatic software, and the expression levels of GST genes in the spirodiclofen-resistant (Sp-R) and susceptible (SS) strains of T. urticae were assayed by quantitative real-time PCR. 【Results】 Two GST genes were cloned and named as TuGSTd1 and TuGSTd2, which were deposited in GenBank under the accession no. KC445659 and KC445660, respectively. The open reading frame of TuGSTd1 is 648 bp in length, encoding 215 amino acids with the predicted molecular mass of 24.47 kDa and the theoretical pI of 5.49, while that of TuGSTd2 is 648 bp in length, encoding 215 amino acids with the predicted molecular mass of 24.57 kDa and the theoretical pI of 6.33. Phylogenetic analysis showed that these two GST genes have 93% amino acid sequence identity with Delta class GSTs of Panonychus citri. Quantitative real-time PCR showed that the relative expression levels of TuGSTd1 and TuGSTd2 in Sp-R were 5.60 and 3.75 times as high as those in SS, respectively. 【Conclusion】 The relative expression levels of GST genes in Sp-R were higher than those in SS, suggesting that the up-regulated expression of GST genes is probably related with the development of resistance to spirodiclofen in T. urticae.

 In order to provide a scientific basis for understanding the effects of the insecticide chlorantraniliprole on Ostrinia furnacalis (Guenée), diet-incorporation bioassays were used to examine the toxicity of chlorantraniliprole to O. furnacalis, and the sublethal effects of the insecticide were investigated using life table analyses under laboratory conditions. The results showed that the LC₁₀, LC₄₀, and LC₅₀ values of chlorantraniliprole on the 3rd instar larvae of O. furnacalis were 0.038, 0.098, and 0.123 mg a.i./L, respectively. After the 3rd instar larvae were treated with LC₁₀ and LC₄₀ levels of chlorantraniliprole, the larval and pupal development were significantly delayed, adult longevity was significantly decreased and fecundity also decreased compared to the control, but the pupal weight (female: P=0.337, male: P=0.121), egg hatchability (P=0.087) and sex ratio (P=0.379) were not affected. Reproduction parameters, such as the net reproductive rate (R₀), intrinsic rate of increase (r_m), and finite rate of increase (λ) in the treatment groups were significantly lower than those in the control group. These results suggest that the LC₁₀ and LC₄₀ concentrations of chlorantraniliprole may reduce the population growth of O. furnacalis.

 Monochamus alternatus Hope is the primary vector for spreading pine wilt disease. Use of attractants in the control of M. alternatus population is effective and pollution-free. In this study, the field test was conducted to evaluate the attractiveness of M. alternatus attractant combined with six kinds of bark beetle attractants to M. alternatus adults. The results showed that there was no significant difference among the combinations of each of bark beetle attractants for Tomicus minor Hartig (3-carene-10-ol), Ips typographus Linnaeus (2-methyl-3-buten-2-ol), Scolytus multistriatus Marsham (4-methyl-3-eptanol), and T. piniperda Linnaeus (verbenol) with M. alternatus attractant (P<0.05). The combinations of attractants for either Dendroctonus brevicomis LeConte (exo-brevicomin) or D. pseudotsugae (1-methylcyclohex-2-en-l-ol) with M. alternatus attractant were less attractive to M. alternatus. Compared with M. alternatus attractant used only, the combination of either D. brevicomis or D. pseudotsugae with M. alternatus attractant was also less attractive as indicated by the species and number of wood-boring beetle individuals captured.