【Aim】 This study aims to ascertain the change patterns of sorbitol content and the mRNA expression level of sorbitol dehydrogenase gene ( SmSDH) in Sitodiplosis mosellana(Géhin) larvae at different diapause stages and to explore the relationship between diapause and sorbitol content and the expression level of SmSDH in S. mosellana. 【Methods】 Colorimetry and real-time quantitative PCR were respectively used to analyze the sorbitol content and mRNA transcription level of SmSDH2aand SmSDH2b in pre-diapause, diapause and post-diapause larvae of S. mosellana collected from a field insectary in Yangling, Shaanxi during May 2013 to March 2014. 【Results】 The sorbitol content in pre-diapause larvaeof S. mosellana was the highest (9.41 μg/mg). During diapause, the sorbitol content in December was the highest, which was 8.50 μg/mg. The sorbitol content in post-diapause larvae was 3.25-3.49 μg/mg, significantly lower than those in pre-diapause and diapause larvae (P<0.05). Change trends of the mRNA transcription levels of SmSDH2a and SmSDH2b in the process of diapause were similar and closely consistent with the decreasing trend of diapause intensity. Namely, the relative expression levels of SmSDH2a and SmSDH2b reduced significantly after the larvae entered diapause (P<0.05) and maintained at a low level during diapause. The relative expression levels of SmSDH2a and SmSDH2b gradually increased and reached the highest after diapause termination. No obvious difference was found in sorbitol content and the relative expression level of SmSDH2a between no-cocooned and cocooned larvae, but the expression level of SmSDH2b in no-cocooned larvae was higher than that in cocooned larvae at the same diapause stage. 【Conclusion】 Sorbitol and SmSDH are involved in diapause ofS. mosellana and play important roles in diapause maintenance and termination.

【Aim】 This study aims to clarify the relationship between fecundity and ovary development of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). 【Methods】 The 1st instar nymphs, 2nd instar nymphs, prepupae, pupae, and the 1-day-old adults were subjected to 41℃ and 45℃ heat shock, respectively, for 2 h and the changes in their ovary development and relative contents of yolk protein were observed. 【Results】 The normal development of reproductive organs and embryos of F. occidentalis  were inhibited by heat exposure, which resulted in the reduction in the number of ovarian tubes and deformity of ovarian tubes and embryo. The yolk protein of F. occidentalis was identified as a phosphorylated and glycosylated lipoprotein, consisting of three subunits with the molecular weight of 116, 70 and 47 kDa, respectively, through electrophoresis and different dyeing methods. The yolk protein synthesis of F₀ generation adults was inhibited when nymphs and prepupae were exposed to high temperature, and the effect of high temperature on the relative content of yolk protein continued to F₁ generation whenthe 1st or 2nd instar nymphs were exposed to high temperature (45℃). 【Conclusion】 The effect of temperature on female fecundity of F. occidentalis is due to its influence on the development of reproductive organs and the synthesis of yolk protein. This study lays a foundation for the further research on yolk protein and vitellogenesis of F. occidentalis.

【Aim】The Eri-silkworm, Samia cynthia ricini, is a lepidopteran insect. Chymotrypsin inhibitors (CI) play important roles in the development and defense of the Eri-silkworm. The analysis of the polymorphism of CIs between different strains and the functional study of CIs in the Eri-silkworm could provide theoretical evidence for controlling Lepidoptera insects. 【Methods】 We investigated CIs in major tissues of 18 strains of S. cynthia ricini by using pH 8.3 and pH 4.0 native polyacrylamide gel electrophoresis. At the same time, the total protein content and CI activity in the hemolymph were determined. 【Results】 Seven CIs were found in the hemolymph of different strains of S. cynthia ricini in the pH 8.3 PAGE, and three CIs were found in the pH 4.0 PAGE. The CIs in the hemolymph maintained very high level from the 3rd day of the 5th instar larvae to the 1st day of the pupae. CIs had relative lower contents in the head, integument and fat body than in the hemolymph, and could not be detectedin the silkgland. 【Conclusion】 The expression level of CIs in S. cynthia ricini is higher than that in the silkworm, Bombyx mori. The polymorphism of CIs in S. cynthia ricini means that CIs vary in the same tissue of different stains and different tissues of the same strain.

【Aim】 The objective of this research is to assess the effects of some snacks in the market on the weight and development of Drosophila melanogaster and then to explore the importance of nutrition balance in the diet for children. 【Methods】 The contents of proteins, fat and carbohydrates of the experimental snacks were detected by Biuret method, Sudan Ⅲ staining method, and iodine tincture staining method, respectively. Fruit flies were reared in the standard food (basal culture medium) or the foods made from the experimental snacks. Five days after egg hatching, the weight of the adults was measured and the midgut was dissected for immunofluorescence experiments. 【Results】 The contents of proteins, fat and carbohydrates in the basal culture medium of D. melanogaster were more balanced, while the experimental snacks were rich in only one kind of these components with imbalanced nutrients. Snacks with high contents of carbohydrates and fat caused fruit flies to be overweight. Meanwhile, theArm/Pros signal of the midgut cells increased significantly, indicating a great increase of stem cells. In addition, the wall of midgut was thickened. Foods lacking carbohydrates or proteins caused developmental disorders Foods with high content of carbohydrates but lacking proteins induced an increase of midgut stem cells, thickening of the midgut wall while loss of weight and slow development. At the same time, foods with high contents of proteins and fat but lacking carbohydrates caused decrease of stem cells, thinning of midgut wall and developmental disorder. For the fruit flies fed with the experimental snacks balanced according to the nutrient proportion of the basal culture medium, the midgut injury and the whole development were improved. 【Conclusion】 Imbalance of nutrition can significantly affect the individual weight, midgut wall and number of stem cells, and then lead to abnormal development in D. melanogaster. Intestinal disorder has a serious impact on its development. These results suggest that favoring snacks only can cause malnutrition, obesity and intestinal dysfunction to children, young children should not prefer snacks only, and the reasonable diet and balanced nutrition are important.

【Aim】 Hexamerins are large hemolymph-proteins that accumulate in insects during the late larval stages and serve important roles throughout insect development and growth. 【Methods】 Our study cloned the hexamerin subunit type 2 (Hex2) gene from the grasshopper Calliptamus italicus and by using qRT-PCR method analysed its expression patterns in different tissues and at different developmental stages. 【Results】 The cDNA of C. italicus Hex2 (CitHex2) is 2 610 bp in length, containing a 2 022 bp open reading frame (ORF) and a 124 bp 3′ untranslated region (UTR). BLAST analysis showed that it shares 80%-84% nucleotide sequence identity with Hex2 genes from other grasshoppers. The encoded protein was predicted to be 673 aa in length with an estimated molecular weight of 78.7 kDa and a theoretical pI of 6.01. The amino acid analysis suggested that CitHex2 is rich in phenylalanine and tyrosine (15.8% of the total aa). Gene expression analysis showed that CitHex2 was expressed at all developmental stages but was differentially expressed during juvenile stages and more highly expressed in female tissues than in male tissues. 【Conclusion】 These findings show that CitHex2 is involved in the development of C. italicus and that it is also associated with reproduction.

【Aim】 As an important pattern recognition receptor, peptidoglycan recognition protein (PGRP) plays an important role in the innate immunity of the silkworm, Bombyx mori. The study aims to identify and characterize a new PGRP gene PGRP-L1 from Bombyx mori, analyze its immune function and the immune signaling pathway that the gene is involved in. 【Methods】 We successfully cloned the gene BmPGRP-L1 from Bombyx mori by RT-PCR. Newly-exuviated 5th instar larvae of B. mori were injected with Escherichia coli, Saccharomyces cerevisiae, Bacillus subtilis and phosphate buffered saline, respectively. After 12 h, the integument and head were collected and used for RNA extraction. RT-PCR and gel electrophoresis were then performed to measure the transcriptional level of BmPGRP-L1 gene. Newly-exuviated 5th instar larvae were injected with dsRNA specific for BmPGRP-L1 and PBS, respectively, then 6 h later injected with the inactivated three microorganisms and phosphate buffered saline, and another 6 h later, tissues were collected and used to detect the transcription levels of related transcription factors (Rel, Cactus and Relish) and antimicrobial peptides (AMPs) genes (Attacin, Moricin and Gloverin). 【Results】 Microbial induction experiments showed that BmPGRP-L1 mRNA level was upregulated in the integument and head of B. mori 12 h after injection of E. coli but presented no change after injection of S. cerevisiae or B. subtilis. RNA interference experiments showed that the expression level of BmPGRP-L1 was successfully knocked down, and the expression level of relish in the newly-exuviated 5th instar larvae subjected to BmPGRP-L1 RNAi was significantly lower than the normal control post E. coli challenge, and the corresponding expression levels of the relevant antimicrobial peptide genes were downregulated to different degrees. 【Conclusion】 The results suggest that BmPGRP-L1 gene participates in the immune response of B. mori against gram negative bacteria E. coli, and BmPGRP-L1 participates in the Imd signal transduction pathway in integument and head of B. mori.

【Aim】 Insect cuticular proteins (CPs) play important roles in development, evaporation resistance and defense against other adverse environmental factors. In this study, the CPs gene family in Delia antiqua was identified based on transcriptome data and their expression in non-diapausing and winter-diapausing puape were investigated, so as to provide a basis for further investigation of the role of CPs in stress tolerance during diapausing period. 【Methods】 The CPs gene family of D. antiqua was identified based on transcriptome data using bioinformatics approaches, and analyses of subcellular localization, phylogeny and conserved domains were also performed. The expression of 12 genes in non-diapausing and winter-diapausing pupae was evaluated by RT-qPCR. 【Results】 Eighty-one CP genes were identified and categorized into CPR (71 genes), CPAP (5 genes) and CPLC (5 genes) subfamily, respectively. They encode proteins with 92-495 amino acids and pI of 3.90-9.93. Bioinformatic prediction showed that the molecular weight of CPs ranges from 8.692 to 52.2 kD. Subcellular localizationprediction revealed that 67 CPs are excreted protein. Among them, 12 genes had significantly different expression patterns between non-diapausing and winter-diapausing pupae, suggesting that they have stage-specific response to low temperature or short-day condition. 【Conclusion】 Functional diversity of some CPs genes from D. antiqua may contribute to the reconstruction of pupal cuticle. Our results would provide a basis for further studies on pupal cuticle structure and their potential functions in stress resistance during the diapausing period.

【Aim】 By the expression and localization analysis of olfactory receptor AcerOrco in the Chinese honeybee, Apis cerana cerana, we researched the expression characteristics of AcerOrco, in order to provide a theoretical basis for further exploring its function. 【Methods】 Real-time PCR and Western blot technology were used respectively to determine the expression profiles of AcerOrco mRNA and protein in five tissues (antennae, head, thorax, abdomen and legs)of nurse and forager bees. By immunohistochemical technique, cellular localization of the olfactory receptor in antenna was analyzed.【Results】 The expression profiling showed that AcerOrco transcripts were detected in all the tested tissues of A. cerana cerana, and the most transcripts were found in antenna. The expression of this gene in different tissues of forager was generally higher than that in nurse. AcerOrco protein were also detected in all the tested tissues, and mainly expressed in antenna and head of nurse and forager. The location result showed that in nurse AcerOrco was detected in sensilla trihodea, but had no obvious expression in sensilla placodea. In forager AcerOrco was mainly expressed in sensilla placodea and sensilla trihodea, with higher expression level in sensilla trihodea. 【Conclusion】 The expression profiles of AcerOrco at mRNA and protein levels were obtained, and the encoded protein was successfully localized in sensilla placodea and sensilla trihodea of antenna of worker bee.

【Aim】 This study aims to investigate the defensive responses in the Chinese tussah moth, Antheraea pernyi induced by different exogenous microbes so as to obtain measures for the disease control and breeding of the moth. 【Methods】 Gram-positive bacteria Bacillus thuringeinsis (Bt) and gram-negative bacteria Escherichia coli (Ec) were selected as the exogenous microorganisms. The concentration of the bacterial solution was adjusted to 10⁶-10⁸ cfu/mL. A. pernyi pupae were induced by inactivated bacteriafor 24, 48, 72 and 96 h, and the physiological indices including hemolymph protein content and the PO activity, CAT activity, antibacterial activity and lysozyme activity in hemolymph were analyzed. 【Results】 Ec and Bt induced prominent changes in several physiological indices of A. pernyi pupae. But the patterns of physiological indices induced by the two bacteria were distinctly different. Haemolymph protein content in A. pernyi pupae increased at 72 h after induction by high concentrations of Ec, while it increased at 24, 48 and 96 h after induction by Bt at various concentrations. The activities of immune defense key enzymes including PO and CAT changed remarkably. The PO activities increased first and then decreased, while the CAT activities showed an increase-decrease-increase tendency after induction by Ec. The PO activities showed an increase-decrease-increase fluctuating pattern, while the CAT activities had no obvious alteration after induction by Bt. Antibacterial activity assay showed that Ec and Bt induced a significant increase in antibacterial activity and lysozyme activity in crude extracts of pupae. But the peak time of antibacterial activity and lysozyme activity was distinctly different. 【Conclusion】 The research results indicated that different treatments of Ec and Bt can induce distinct defense responses in A. pernyi pupae, and the variation patterns of physiological indices are related to different kinds of microorganisms and treatment time and concentration. It is speculated that gram positive bacteria and gram negative bacteria have different induced defense mechanisms. We propose that the several physiological indices can be used as markers for immune defense response to exogenous microbes in A. pernyi.

【Aim】 To clarify the bacterial diversity in the intestine of larval  Procecidochares utilis. 【Methods】 The V6 regions of the 16S rDNA genes of intestinal bacteria in  P. utilis larvae was sequenced by Illumina HiSeq techniques. The numbers of sequences and operational taxonomic units (OTUs), species abundance and alpha diversity in samples were analyzed using USEARCH and QIIME softwares. 【Results】 A total of 1 593 506 reads were obtained, which were combined to 1 579 372 tags. After filtration, 1 572 860 tags were clustered into 1 341 OTUs. They were annotated into 13 phyla, 4 classes, 6 orders, 7 families, 10 genera, and 4 species. The Proteobacteria was the most dominant, accounting for 99%. At the genus level, Wolbachia was the dominant bacteria(45%). 【Conclusion】 The results show that the bacteria in the intestine of larval P. utilis are diverse. The information of species richness will lay a foundation for further research on the association of the intestinal bacteria with host plant to reveal feeding specialization in P. utilis.

【Aim】 Mate choice is a central process of sexual selection, and whenever fluctuations in the cost of reproduction and variance in mate quality occur, the traditional sex roles may also vary. In order to testify the thought that males can also be choosy like the females under certain circumstances, we studied male and female mating success in relation to adult body size as an indicator of fitness in Menochilus sexmaculatus (Fabricius) (Coleoptera: Coccinellidae). 【Methods】 Small and large adults of both sexes were selected randomly from the stock culture and subjected to male and female mate choice trials. The offspring of successful pairs were also tested for their mating success by placing them in mate choice trials too. 【Results】 Mate choice experiments revealed the presence of size dependent mating success in both male and female mating trials. Males discriminated between the females on the basis of their quality, i.e., body size which is an indicator of fecundity function. In female mating trials also large males achieved higher mating success than small males. Large females produced more eggs than did small females regardless of paternal size, and body size, however, did not influence egg viability. The offspring of large parents developed faster and lived longer than those of small parents, but did not display any advantage in terms of sexual desirability or competitiveness as mates when they were put in mate choice with the offspring from stock culture. 【Conclusion】 This study revealed the presence of mutual mate choice in this insect with size being the trait of interest.

【Aim】 As a new pest on American ginseng, Panax quinquefolium L.，the root mite Schwiebea similis Manson bores into and feeds on tissues inside roots of the plant, causing remarkable losses. The study aims to determine its feeding amount of roots and to estimate its economic threshold in the future. 【Methods】 Female mites were inoculated onto powders of the ginseng root dusted on wet fine sands in plastic rings within plastic dishes in the experiment, which was conducted under the conditions of seven levels of initial females inoculated (N₀) (1, 2, 3, 4, 5, 6 and 7 ♀ per ring) and five gradients of rearing temperatures (T) (15.6, 18.5, 21.2, 24.5 and 27.2℃). Five variables including duration of mites living stably on the food (D), number of mites counted on the peak day (Np), per capita reproduction of females (PCR), adult equivalent adjusted from Np (AE), and feeding amount of fresh ginseng tissues by a filial mite from egg to adult (FA) were recorded and analyzed. 【Results】 Variable D decreased rapidly against T, and slowly against  N₀. N_p increased significantly with N₀, and the equation was N_p =21.8+17.2 N₀. PCR decreased significantly against N₀, the equation was PCR=63.4-28.1 N₀+6.2 N₀ ²-0.4N₀³, and its track was reverse with that of N_p. A crowding effect was found among mites. AE increased significantly with N₀ , and the equation was AE=16.2+12.7N₀. FA=0.25±0.13 mg/adult. 【Conclusion】 The five variables reflect the range of feeding amount and the reproductive potential of the laboratory populations of S. similis; not only does each of them show specialty, but also relates to others. As important bionomics, the values estimated in the experiment would be essential in the calculation of its economic threshold, and the methods used would also be beneficial in similar studies.

【Aim】 UV-absorbing film can absorb light below 380 nm wavelength to affect the vision response of insects and shows potential in pest management. This study aims to assess the feasibility of the physical control approach. 【Methods】 We compared the population dynamics of three main pests (Frankliniella occidentalis, Bemisia tabaci, and Myzus persicae) on eggplants (Solanum melongena), as well as the growth of plants and quality of fruits， between the UV-absorbing greenhouse and the common greenhouse (the control). 【Results】 The maximum population density of F. occidentalis, B. tabaci, andM. persicae in the UV-absorbing greenhouse was only 44.3%, 50.4% and 37.5% of that in the common greenhouse, respectively (P<0.05). In addition, the plant height increased insignificantly (P>0.05), the yield, fruit weight and circumference of eggplants decreased, and fruit color of eggplant was lighter in the UV-absorbing greenhouse compared to the control. The contents of ascorbic acid, soluble carbohydrate, titratable acid, crude fat and anthocyanin in the eggplant fruits in the UV-absorbing greenhouse decreased and the contents of Ca, K, Cu and Zn in the UV-absorbing greenhouse increased significantly in particular period as compared to the control (P<0.05). 【Conclusion】 Our research indicated that UV-absorbing approach could restrain the population increase of the three main pests on eggplant in the greenhouse significantly. However, this approach has negative effects on the growth of plant and quality of fruits. Further research is needed to evaluate this approach in cultivars of eggplants and other vegetables in future.

【Aim】 In order to study how  Breynia vitis-idaea controls the population of  Epicephala vitisidaea.【Methods】 The phenology of B. vitis-idaea  and the biology of E. vitisidaea  were recorded.The flower-visiting Epicephala  moth species were identified by dissecting their genitalia. For calculating larval survivorship, the number of larvae inside the fruit, the number of exit holes and oviposition scars on the fruit were counted by dissecting the stalked and non-stalked fruits in summer and late autumn. Finally, the proportion of stalked and non-stalked fruits in summer and late autumn was calculated. 【Results】 In Xiamen, Fujian Province, B. vitis-idaea plants have five peak fruiting stages annually and the flower-visiting Epicephala moths have five generations each year. The species of moth was identified as E. vitisidaea by contrasting its genitalia. E.vitisidaea  larvae need to consume 2-4 seeds to develop into mature larvae. B.vitis-idaea could produce two types of fruits, stalked and non-stalked. The larval survivorship of E.vitisidaea was obviously higher in non-stalked fruits than in stalked fruits as well as in late autumn than in summer. Meanwhile, the proportion of non-stalked fruits of B.vitis-idaea was obviously higher in late autumn (82.04%) than in summer (31.53%). 【Conclusion】 This study revealed the mechanism by which mutualistic interactions are more stable. B. vitis-idaea can control the larval survivorship of E. vitisidaea by producing the stalk in base of fruits. By seasonally regulating the ratio of stalked and nonstalked fruits, Breynia plants prevent seed overconsumption in summer and ensure Epicephala survival through the winter. The auto-regulating mechanism of B. vitis-idaea plays an important role in keeping stability of mutualistic system between B. vitis-idaea and E. vitisidaea.