Signal inactivation is a critical step in the olfactory dynamic process, in which various odorant-degrading enzymes are involved. In this study, the cDNA of a cytochrome P450 gene, CYP6AE21, was cloned from the male moth antenna of Bombyx mori by RT-PCR method. CYP6AE21 contains a 1 572 bp open reading frame (ORF), which encodes a putative protein of 523 amino acids. This cDNA-deduced protein has a predicted molecular weight (MW) of 60.5 kD, isoelectric point (pI) of 8.4, and a P450 characteristic structure heme-binding region. A single intron is localized at the same site in each of the P450 gene CYP6AE21 and CYP6AE2 from B. mori, and two corresponding exons with the same size exist in both of the genes. The two genes share 94.5% nucleotide similarity, and cluster on the same chromosome in a head-to-tail arrangement separated by an approximately 7.6 kb intergenic region. CYP6AE21 was highly expressed in larval head and fat body, and both male and female moth antenna. It was also expressed in other tissues of larvae and some tissues of moth. NADPH cytochrome P450 reductase (CPR), a very important component of monooxygenase system, was also highly expressed in the moth antenna, and expressed in other moth tissues at low levels. Subcellular localization analysis showed that the expression product of CYP6AE21 is localized in cytoplasm. It is so inferred that CYP6AE21 and CYP6AE2 could have been formed by gene duplication of either of them, and CYP6AE21 might participate in the degradation of odorants after these components are internalized into cells.

Cryptochrome gene (Cry) is one of the major biological clock genes which were widely distributed in bacteria and eukaryotes. Cry genes of insect species are clearly divided into two types, Cry1 and Cry2. Only Cry1 is expressed in Drosophila, while only Cry2 was expressed in bees and other hymenopteran insects. In order to explore the molecular mechanism of circadian clock in lepidopteran model insect Bombyx mori and the evolution of CRY proteins in insect species, we cloned the cDNA sequences of Bmcry1 (2 166 bp, GenBank accession no. HM747059) and Bmcry2 (2 389 bp, GenBank accession no. HM747060), and obtained their gene sequences (GenBank accession no. HM747057 and HM747058, respectively) by sequence alignment and assembly. Bmcry1 have 12 exons and 11 introns, while Bmcry2 have 9 exons and 8 introns. Chromosome mapping showed that Bmcry1 and Bmcry2 were located on chromosome 17 and chromosome 15, respectively. We predicted the three-dimensional structures of Bmcry1 and Bmcry2 by homology modeling. The results showed that the FAD entrances are large and deep, consistent with the fact that CRY proteins do not bind with pyrimidine dimers, and the surfaces of Bmcry1 and Bmcry2 are more negatively charged, only FAD entrances have accumulated positive charge. Moreover, we researched the molecular evolution of Bmcry1 and Bmcry2 by multiple sequence alignment, protein motif analysis, functional domain analysis and cluster analysis. The results showed that Bmcry1 and Bmcry2 belonged to insect CRY1 and CRY2, respectively, and were closely to the corresponding proteins in other lepidopteran insects like Antheraea pernyi. Similar to the CRY proteins in other insects, Bmcry1 and Bmcry2 have DNA photolysis enzyme domain and FAD binding domain. However, the two domains have different conservative sites between CRY1 and CRY2 in insect species, and their protein motifs are also different. Our experiment provided a basis for further investigating the mechanism of molecular evolution and function of CRY1 and CRY2 in B. mori.

Glutathione-S-transferases (GSTs) play an important role in detoxification and can be induced. In order to study the relationship between the metabolism of the plant secondary metabolite rutin and the GSTs genes of Bombyx mori, we detected the transcription levels of Epsilon-class GSTs genes in different tissues of the 5th instar larvae and those treated with rutin (5×10^-1, 5×10^-2 and 5×10^-3 ng/μL) using dual-spike-in qPCR. The results showed that rutin (5×10^-2 ng/μL) can induce a significant change of the transcription levels of GSTs genes. In the midgut, BmGSTe1, BmGSTe2 and BmGSTe6 had higher transcription levels and reached the maximum at 24 h after induction; in fat body, however, BmGSTe1, BmGSTe6 and BmGSTe7 had higher transcription levels and reached the peak at 2 h, 2 h and 4 h after induction, respectively; and the transcription level of the GSTs genes did not change significantly or was undetectable in Malpighian tubules. Compared with the treatment with 5×10^-2 ng/μL rutin, 5×10^-1 ng/μL rutin could induce a little change of the transcription levels of GSTs genes and the time when the expression peak occurred was not the same. However, 5×10^-3 ng/μL rutin could not induce the change of the transcription level of the GSTs genes. The results suggest that the Epsilon-class GSTs genes play an important role in the metabolism of rutin.

As a member of the antimicrobial peptide family, attacin plays a key role in insect innate immune system. In this study, a cDNA of 819 bp encoding attacin-2 was cloned from housefly (Musca domestica) by RACE based on the EST information, and named Mdatta2. The cDNA sequence contains a 726 bp open reading frame (ORF) encoding 241 amino acid residues and is flanked by a 42 bp 5′-UTR and a 51 bp 3′-UTR. The deduced peptide contains a putative signal peptide of 22 amino acids. The amino acid sequence of Mdatta2 showed the highest identity (46%) with that of Drosophila ananassae by Blastp analysis. The phylogenetic tree indicates that the attacin-2 from housefly and those from other dipterans are descended from a single common ancestor and belong to Attain_C superfamily. The expression of Mdatta2 transcript was measured by real-time PCR. The results demonstrated that after housefly larvae were challenged with Escherichia coli and Staphylococcus aureus, respectively, the mRNA level of Mdatta2 at 3 h and 6 h post-challenge was up-regulated and significantly higher than that of the blank control. The expression of Mdatta2 is inducible, and its expression level varies with the induction time, suggesting that Mdatta2 may play an important role in housefly defensive system.

 To explore the mechanism of physiological and biochemical effects of wasp parasitization on its hosts, levels of glycogen, trehalose, lipids and proteins in the haemolymph of host Mythimna separata larvae parasitized and unparasitized by Microplitis mediator were examined. The results showed that the content of glycogen in parasitized M. separata larvae was higher than that in unparasitized host larvae. Under diapause condition for 12 days, the content of glycogen in parasitized larvae reached to 7.93 μg/mL which was significantly higher than that in unparasitized hosts (4.70 μg/mL) (P<0.05). Under non-diapause condition for 6 days, the content of glycogen in parasitized larvae reached to 14.35 μg/mL which was significantly higher than that in unparasitized hosts (5.47 μg/mL) (P<0.05). The contents of trehalose were not significantly different between parasitized and unparasitized host larvae under diapause condition. But under non-diapause condition for 4 days, the content of trehalose (46.82 μg/mL) in parasitized larvae was significantly higher than that in unparasitized larvae (26.72 μg/mL). The contents of lipids and proteins were not significantly different between parasitized and unparasitized larvae under diapause or non-diapause conditions. The results suggest that: (1) the content of glycogen was higher in the haemolymph of larvae parasitized by M. mediator; (2) the non-diapause conditions are the main factors which influence the content of trehalose in parasitized larvae; (3) the larvae of M. separata possess higher ability of adaptation and tolerance to the wasp parasitism.

In insects, carbohydrates play an important role in both energy metabolism and material synthesis. The main purpose of the present study is to evaluate the effects of four compounds (scopolamine hydrobromide, nicotine, esculin and saponin) on trehalase activity and content of related carbohydrates in larvae of the cotton bollworm, Helicoverpa armigera (Hübner). The results showed that at 96 h after treatment in larvae with saponin, the larval growth was significantly inhibited, and the mortality was enhanced with the increasing saponin concentration. At the dosages of 10, 20, 40 g/L saponin, the mean weights of larvae were 0.194, 0.089 and 0.034 g, being 86.99%, 39.91% and 15.24% of the control, respectively. According to the determined trelalase activity as well as the activities of related metabolic enzymes, β-glucosides significantly inhibited the trehalase activity in the midgut while alkaloid inhibited the trehalase activity in the haemolymph and fat body obviously. Trehalase activity in the midgut was about 54.21% of the control at 96 h after the larvae were exposed to saponin at the dose of 40 g/L, while 83.73% of the control after the larvae were exposed to esculin at the dose of 30 g/L. Trelalase activities in both the hemolymph and fat body were 7.24% and 71.43% of the control, respectively, at 96 h after the larvae were exposed to scopolamine hydrobromide at the dose of 20 g/L, while 26.29% and 33.44% of the control after the larvae were exposed to nicotine at the dose of 20 g/L. Trehalose activity in the hemolymph was all increased by scopolamine hydrobromide, nicotine and esculin. All the four compounds affected the activity of glycogen phosphorylase. Saponin inhibited significantly the activity of glycogen phosphorylase in the midgut and fat body. The glycogen level changed consequently in contrast to the activity of glycogen phosphorylase with the increasing of compound concentration. When the larvae fed with botanical compounds, the change of glucose content in the hemolymph was consistent with that of trehalose content, and glycogen content in fat body was all declined to some extent. The results proved that β-glucosides could inhibit the trelalase activity, and this may have reference value in developing new pesticide compounds.

Segmentation is critical to insect embryogenesis, yet little is known about this process in Locusta migratoria manilensis (Meyen) which is an important pest. In this study, the spatio-temporal process of segmentation in L. migratoria manilensis was observed by using immunohistochemical and fuchsin staining methods. The results showed that the zygote nucleus quickly divided and migrated to the egg periphery after fertilization, and then the nuclei were condensing at the posterior end of the egg where a circular blastodisc formed. The blastodisc subsequently differentiated into head lobe and posterior germband. With elongation of the germband, the first segment was observed at thoracic region at about 50 h after egg laid, and then other segments, including 3 head segments, 3 gnathal segments, 3 thoracic segments, and 10 abdominal segments, gradually formed in a sequential pattern within 44 h. The thoracic and gnathal regions were added one or more segments at a time, while only one segment at a time was formed for the abdomen. Our results further confirmed that L. migratoria manilensis is a classic short germband insect with the anterior thoracic region as the morphological differentiation center. Meanwhile, the developmental rates of embryo vary among different locust species, while the segmentation patterns and the relative time required for segmentation are identical.

 The toxicity of eleven insecticides of different categories on adults of Trichogrammatoidea bactrae Nagaraja and the sublethal effects of insecticides on their reproduction under laboratory conditions were studied, so that the safety of insecticides to adults of T. bactrae was evaluated. The results showed that the adults of T. bactrae were the most susceptible to avermectins at 8 h after exposure to fresh, dry insecticide films in glass vials, the LC₅₀ and sublethal concentration (LC₃₀) values were 0.1984 mg/L and 0.1660 mg/L, respectively, and second susceptible to fipronil (LC₅₀ and LC₃₀ values were 0.2027 mg/L and 0.1903 mg/L, respectively), chlorfenapyr (LC₅₀ and LC₃₀ values were 0.3069 mg/L and 0.2038 mg/L, respectively), spinosad (LC₅₀ and LC₃₀ values were 1.3630 mg/L and 1.0481 mg/L, respectively), cartap (LC₅₀ and LC₃₀ values were 8.1042 mg/L and 6.7891 mg/L, respectively), betacypermethrin (LC₅₀ and LC₃₀ values were 10.3647 mg/L and 5.8035 mg/L, respectively) and diafenthiuron (LC₅₀ and LC₃₀ values were 11.5318 mg/L and 9.9212 mg/L, respectively). The LC₃₀ values of avermectins, chlorfenapyr, cartap, diafenthiuron, spinosad and fipronil had significant effects on the longevity and fecundity of T. bactrae. After treated with these insecticides, the longevity of females (1.00-1.67 d) was shortened, and the number of eggs parasitized per female (0-21.70) decreased, and therefore the life table parameters (R₀, r_m, λ and T) of T. bactrae were statistically lower than those in the control. The field recommended concentration of indoxacarb, chlorfluazuron, Bacillus thuringienesis and tebufenozide had no effect on the longevity and fecundity of T. bactrae, but after treated with these insecticides, the R₀, r_m and λ of T. bactrae were higher than those in the control. However, the longevity of females (3.77 d) was significantly extended, and the number of eggs parasitized per female (55.47) was significantly increased after the adults of T. bactrae were exposed to betacypermethrin, and therefore the life table parameters of T. bactrae were statistically higher than those in the control. The results suggest that chlorfluazuron, indoxacarb, B. thuringienesis and tebufenozide are safe to T. bactrae, so these insecticides are compatible to these parasitoids when used for control of Plutella xylostella. Diafenthiuron, however, is evaluated as harmful to the fecundity of T. bactrae, and timing of application of this insecticide is critical.

 In order to clarify the mechanisms of deltamethrin resistance in Tetranchus urticae Koch. Pyrethroid acaricide fenpropathrin was used to select the resistance in T. urticae in the laboratory. Selected with fenpropathrin for 38 generations, T. urticae developed 247.35-fold resistance to fenpropathrin. The activities of detoxification enzymes were measured and compared between the susceptible strain (S) and the fenpropathrin-resistant strain (Fe-R) of T. urticae. The results showed that the activities of carboxylesterase (CarE), acid phosphatase (ACP), alkaline phosphatase (ALP), glutathione S-transferases (GSTs) and mixed function oxidase (MFO) in Fe-R₃₈ were significantly higher than those in S strain, increased by 1.822-, 13.941-, 3.789-, 4.262- and 17.386-fold, respectively. However, except that the activity of MFOs in Fe-R₂₅ and Fe-R₃₂ showed significant difference from that in S strain (P< 0.05), the activities of other detoxification enzymes (CarE, ACP, ALP, GSTs) in the resistant strain selected for 9, 19, 25, and 32 generations were significantly different with those in S strain. The activities of all the detoxification enzymes in the resistant strain selected for 38 generations were significantly different with those in S strain (P<0.05). These results suggest that with the increasing of selection generations (after the 25th generation) with fenpropathrin, the increased activity of MFO may the main factors responsible for the resistance of T. urticae to fenpropathrin.

 In order to determine the active compounds from Derris cavaleriei vines and their antifeedant activities against Plutella xylostella larvae, the active compounds were isolated by activity-guided fractionation with column chromatography and identified on the basis of MS and NMR data, and the antifeedant activity was determined by sandwich method. The results included that four compounds i.e. isolonchcarpin, magnificol, ovaliflavanone and millettocalyxin C had been isolated from the plant vines for the first time, and isolonchcarpin, magnificol and millettocalyxin C exhibited antifeeding activity, with the AFC₅₀ values of 25.5, 92.8 and 115.9 mg/L against the 3rd instar larvae of P. xylostella at 48 h after treatment, respectively, suggesting that the three compounds are antifeedant compounds against P. xylostella derived from the plant vines. The elucidation of these chemicals is important not only for understanding the insectplant relationships, but also for their potential in P. xylostella control.

Ophraella communa LeSage (Coleoptera: Chrysomelidae) is an important and specific natural enemy of Ambrosia artemisiifolia L. (Asterales: Asteraceae). To understand the effects of short-term low temperature stress on development and fecundity of O. communa, the survival rates and developmental durations of eggs, larvae and pupae, and survival rate, longevity and fecundity of adults of O. communa under short-term (2 h) low-temperature (2, 5, 8, 11, and 14℃) stresses were determined in five environmental chambers (a relative humidity of 70%±5% and a photoperiod of 14L∶10D). The results showed that the hatch rate of eggs decreased with the decreasing temperature. The hatch rate of eggs was 90.7% at 28℃ (the control), while the lowest hatch rate of eggs (72.2%) was observed in the 2℃-stress treatment. The survival rates of larvae were significantly affected by low-temperature stresses. The larval survival rates were 40.0%, 42.7%, 62.7%, 72.7%, 70.0% and 78.0% in 2℃-, 5℃-, 8℃-, 11℃- and 14℃-stress treatments and the non-stress control, respectively. After 2-14℃ short-term stresses, the survival rates of pupae was 88.0%-92.0%, which did not differ from that of the control (90.7%) (P>0.05). The longevity and fecundity of adults decreased significantly and the survival rate of adult was also significantly affected under low temperature stresses, and the survival rate of adults decreased significantly along with the decreasing temperature. Female and male survival rates were 79.0% and 51.0% after 2℃-stress, respectively. The short-term (2 h) low temperature (2-14℃) stresses had significant effects on different developmental stages of O. communa except the pupal stage. It is so inferred that the rapidly dropping temperature may be one of important factors resulting in a low population level of O. communa in early spring in the field.

Simulating the relationship between temperature and developmental rate is an important content in entomology research. The traditional non-linear models, including Logan model, Lactin model and Wang model, however, have the disadvantage of utilizing information incompletely, over-fitting, etc. In the current paper, an improved support vector regression (SVR) model has been developed to analyze the relationship between temperature and pupal development of the cotton bollworm (Helicoverpa armigera). The results showed that the SVR had a higher performance on model-fitting and predict ability than other non-linear models based on the observed data (92 samples), with determination coefficients (R²) of 0.998 and 0.996, respectively. Estimation of the three fundemental points of temperature of the pupal stage with the improved SVR was more credible. On the basis of 20 samples, the Lactin model had the highest performance with R² of 0.958 among the mentioned traditional non-linear models, but it was still obviously lower than that of the improved SVR with R² of 0.981. When the number of samples was reduced to 12, the R² of SVR slightly declined to 0.964, while the traditional non-linear models were not applicable to the independent prediction any more. The results suggest that the improved SVR is superior in dealing with small sample set than traditional non-linear models, and the improved SVR may be useful in forecasting outbreaks of pests and artificial breeding of insects.

The honeybee Apis mellifera ligustica and the bumblebee Bombus hypocrita are the two main pollinators for greenhouse agriculture in China. Their pollination behavior and activity patterns differ on some crops. In order to employ the most appropriate bee species and improve pollination efficiency, we investigated the pollination behavior of the two bee species and the factors that influence it in greenhouses for peaches between 2008 and 2010. The results showed that diurnal activity differed between the species. Compared with A. mellifera ligustica, B. hypocrita started work at a lower temperature and had a longer working day, as well as a longer visiting time per flower, and the number of foraging bees was almost the same at different distances from the nest. In contrast, the number of foraging bees of A. mellifera ligustica declined with their distance from the hive. In greenhouses, the influences of environmental factors on bees were basically the same. Temperature was the most important factor for limiting pollination activity, while the humidity, nectar concentration of a flower, and the illumination intensity, were all less important. The nectar volume per flower was not directly correlated with the level of bee activity. In conclusion, B. hypocrita should be favored for pollination in peach greenhouses. Furthermore, in order to improve the efficiency of bee pollinators, greenhouse conditions may need to be adjusted.

This paper deals with a taxonomic study of the genus Tuarega Uvarov, 1943, with 2 new species, namely Tuarega sahara sp. nov. and Tuarega parisi sp. nov., from Sahara described. T. sahara sp. nov. is similar to T. insignis (Lucas, 1851), but it differs from the latter in four characters: the widest width of pronotum longer than length of metazona, median vein of tegmen not combined with cubital vein, radius vein of tegmen with 5 branches, cubital vein of tegmen with 2 branches. T. parisi sp. nov. is similar to T. insignis, but it differs from the latter in four characters: the widest width of pronotum longer than length of metazona, median vein of tegmen not combined with cubital vein, median vein of tegmen with 2 branches, cubital vein of tegmen with 2 branches. It is also similar to T. sahara sp. nov., but it differs from the latter by radius vein of tegmen with 7 branches and median vein of tegmen with 2 branches. A key to all known species of Tuarega is given. The type specimens are deposited in the Spanish National Museum of Natural Sciences (Museo Nacional de Ciencias Naturales, MNCN).

Insect physiology is one of the fastest-growing disciplines of the entomology. Through analysing the insect physiology programs funded by Zoology Division of Life Science Department, the National Natural Science Foundation of China (NSFC) over the last twenty years, we found that the Division supported 92 programs for General Projects, accounting for 7.26% of the total 1 208 funded proposals. Sixteen applications for Young Scientists’ Fund were supported and accounted for 12.12% of the 132 proposals funded. Regarding the key programs, 10 projects were funded. The development of basic researches on insect physiology in our country has extended from tissue and cell level into molecule and gene level. Studies of insect genomics, functional gene and hormone regulation in insect development, co-evolution between host plants, insects and natural enemies, insect immunity and its mechanism, etc., will be the development tendency of insect physiology. In the future, researches on insect physiology in our country should be enhanced in such areas including research direction, talents squad construction, cooperation among nations and the leading role of funds.

Mouthpart sensilla play significant roles in insect feeding activities. However, sensilla on the mouthparts in adult hangingflies have not been reported. The mouthpart sensilla of Bittacus sinensis Walker adults were investigated using scanning electron microscopy. The results indicated that the sensilla are mainly borne on the epipharynx and maxillary and labial palpi, and can be categorized into eight types: basiconic, trichoid, chaetic, digitiform, palmate, campaniform, cylindrate sensilla and Böhm’s bristles. Basiconic and chaetic sensilla are the most abundant. Trichoid sensilla are mainly located on the cardines, stipites, submentum and mentum. Campaniform sensilla and Böhm’s bristles are only distributed on the maxillary and labial palpi. The sensilla are similar on the distal segments of maxillary and labial palpi, mostly being basiconic sensilla. No sensillum was discovered on the highly sclerotized mandibles, galeae and laciniae. The implication of the mouthpart sensilla in insect classification is briefly discussed.