【Aim】 Lipids play important roles in insect diapause. Our study aimed to ascertain the change law of lipid content in diapause of Sitodiplosis mosellana (Géhin) and explore the relationship between diapause and lipids in S. mosellana. 【Methods】 Vanillin-sulfuric acid colorimetry was used to analyze the total lipid and triglyceride contents in pre-diapause, diapause and post-diapause larvae and different stage pupae of S. mosellana in a field insectary in Yangling, Shaanxi during May 2008 to January 2010. 【Results】 The contents of total lipids and triglyceride in pre-diapause larvae were 378.12 and 291.69 μg/mg, respectively, significantly higher than those in diapause larvae (P<0.05). In one-year diapause cycle, total lipid and triglyceride contents in winter were the highest, which were 335.29 and 275.72 μg/mg in cocooned larvae in January of the next year, respectively, significantly higher than those in other stages during diapause (P<0.05). A similar seasonal variation trend was observed in total lipid and triglyceride contents of both nococooned and cocooned larvae in one-year diapause cycle, but there were higher contents in cocooned larvae than in no-cocooned larvae at the same diapause stage. No obvious difference was found in total lipid and triglyceride contents between the 1st and 2nd year of diapause larvae (P>0.05). The total lipid and triglyceride contents reduced gradually with development after diapause termination, being significantly lower in mid-pupae and late pupae than in active larvae (P<0.05). 【Conclusion】 Total lipid and triglyceride contents in pre-diapause, diapause and post-diapause larvae and pupae of S. mosellana were significantly different, suggesting that diapause of S. mosellana is closely related to contents of lipids.

【Aim】 This study aims to explore the expression profiles of insect cuticle protein (ICP) gene in different larval tissues and developmental stages of Monochamus alternates. 【Methods】 The gene coding for cuticle protein of M. alternatus was cloned by rapid amplification of cDNA ends (RACE) method. Real-time quantitative PCR was used to detect the gene expression profiles. 【Results】 The cloned cuticle protein gene from M. alternatus was named as MoalICP (GenBank accession no. AGX00998.1). The opening reading frame of MoalICP is 408 bp in length, encoding a protein of 135 amino acids with an estimated molecular mass of 14.51 kDa. Multiple sequence alignment indicated that MoalICP shares the highest amino acid sequence identity (79%) with ICP from Apriona germari (AAM66718.1), and 35%-45% identities with ICPs from 19 insects including Nasonia vitripennis (NP_001161297.1), Drosophila mojavensis (XP_002005461.1), and Papilio polytes (BAM18876.1) at the amino acid level. There is a transmembrane segment between the 10th and the 26th amino acid sites in MoalICP. MoalICP gene was expressed in head, body wall, fat body, haemocytes, Malpighian tubules, and midgut body of larvae. The relative expression level of MoalICP gene in pupae and adults was 44% and 161% of that in larvae, respectively. 【Conclusion】 MoalICP has high amino acid sequence identity with ICPs from other insects. The MoalICP gene is expressed widely in M. alternatus larvae, and has the highest expression level in adults. The present study provides reference for further research on functions of MoalICP and epidermis chemistry of M. alternatus.

【Aim】 This study aims to clone two general odorant receptor genes, analyze their sequences and investigate their expression profiles in different tissues of adults of the cotton bollworm, Helicoverpa armigera. The findings will provide basic knowledge for further functional study of these two odorant receptor genes. 【Method】 We cloned the full-length cDNA sequences of two odorant receptor genes by PCR and RACE techniques. The structure prediction, sequence alignment and phylogenetic analysis of the coding products of these two odorant receptor genes were performed using different bioinformatics softwares. The expression profiles of these two genes in different tissues were investigated by using semi-quantitative RT-PCR. 【Results】 Two full-length cDNA sequences encoding odorant receptors were obtained and named as HarmOR9 and HarmOR29 (GenBank accession number KJ188252 and KJ188253, respectively). Sequence analysis showed that the full-length of HarmOR9 gene is 1 206 bp, which encodes a polypeptide of 401 amino acids, and the full-length of HarmOR29 gene is 1 188 bp, which encodes a polypeptide of 395 amino acids. Sequence alignment and phylogenetic analysis of the coding products of these two odorant receptor genes with reported odorant receptors from lepidopteran insects including Helicoverpa assulta, Bombyx mori, Heliothis virescens and H. armigera showed that the coding products of these two odorant receptor genes are obviously different from sex pheromone receptors, but cluster together with other general odorant receptors. The results of semi-quantitative PCR showed that these two odorant receptor genes were highly expressed in antennae with no significant difference between male and female, HarmOR29 was not expressed in other tissues, and HarmOR9 was slightly expressed in male labial palps but not in other tissues. 【Conclusion】 In this study, two odorant receptor genes were cloned in H. armigera. Sequence analysis showed that the coding products of these two genes own typical characteristics of odorant receptors and belong to general odorant receptors. The two odorant receptor genes were highly expressed in adult antennae, with no difference between male and female. Based on the findings, we infer that they may be involved in the identification of general odors.

【Aim】 Ty3/gypsy is a retrotransposon that is widespread in many organisms. Aspartic protease (AP) gene is important for the retrotransposon transposition. Since the AP gene is difficult to be cloned based on degenerate primers because the members of AP family have low similarities, there are few researches about AP genes. 【Methods】 The AP gene in Ty3/gypsy retrotransposon was cloned from Chilo suppressalis (Walker) with PCR method, and its sequence characteristics and variations in the Chinese populations were analyzed. 【Results】 The AP gene has a single open reading frame (ORF) of 528 bp encoding a protease of 175 amino acids (GenBank accession no.: KF886014). The Conserved Domain Search analysis showed that there is a conserved Asp_protease_2 domain in this AP protein. Seventy copies of AP gene were cloned from 7 field populations. Multiple sequences alignment revealed that there are 46 single-base substitutions including 31 transitions and 15 transversions. Sixty-nine of 70 copies have intact ORF. The base changes of A→G (15) and T→C (11) occur more frequently than the others. 【Conclusion】 There is no significant relationship between the patterns of base substitutions and the distribution area of C. suppressalis. This study will be helpful to investigate the variation features of retrotransposon.

【Aim】 This study aims to investigate the neuropil structures of the brain and the suboesophageal ganglion in larvae of the cotton bollworm, Helicoverpa armigera (Hübner) and to reconstruct their three-dimensional models. 【Methods】 The immunohistochemistry was used to characterize the anatomy of the brain and the suboesophageal ganglion. The laser scanning confocal microscope was used to acquire the confocal image stacks of the brain and the suboesophageal ganglion, which were subjected to image analysis, and the digital three-dimensional reconstructions were created by the AMIRA software. The volumes of the brain and the suboesophageal ganglion and their neuropils were measured by using the statistic tool of AMIRA software and the relative size was analyzed. 【Results】 The larval brain and the suboesophageal ganglion are connected by one pair of circumoesophageal connectives. The brain is composed of protocerebrum, deutocerebrum and tritocerebrum. The protocerebrum contains three prominence neuropils, i.e., optic lobes, mushroom bodies and central body. The other neuropils are lateral, ventral and superior protocerebra, which account for 59.65% of the brain neuropils. Their boundary, however, is hard to discriminate. The deutocerebrum mainly consists of a pair of antennal lobes. The tritocerebrum is located in ventral of the brain and under the antennal lobe. Compared with protocerebrum and deutocerebrum, the volume of tritocerebrum is smaller. The suboesophageal ganglion is also a fusion of three neuromeres, i.e., mandibular neuromere, maxillary neuromere, and labial neuromere from anterior to posterior. Their boundaries are obscure. 【Conclusion】 The neuropils of the brain and the suboesophageal ganglion were presented and their digital three-dimensional models were reconstructed. The models can be rotated and viewed at any angle, thus facilitating the identification of the neuropils and their spatial relationships. The results of this study provide knowledge about basic neuroanatomical principles for understanding the mechanisms underlying information processing, integrating and behavioral regulation.

【Aim】 Mosquito repellents are a group of compounds which can protect human from mosquito biting. However, the repelling mechanisms are still unclear. In this study, theoretical calculations were applied to investigate the molecular association between four important human-derived attractants (acetic acid, propionic acid, butyric acid and pentanoic acid) and twenty-two terpenoid repellents, to find out the relationship between this kind of interaction and repellency, and so to clarify the repelling mechanisms from a new perspective.【Methods】 Structures of attractants, repellents and attractant-repellent complexes were built and optimized by GAUSS View and GAUSSIAN, and association energy and geometrical parameters were obtained. Descriptors for model building were calculated by AMPAC and CODESSA. The quantitative structure-activity relationship (QSAR) models were built to analyze the relationship between the structural descriptors and the logarithm value of the corrected repelling time (logCRR) against Aedes albopictus. 【Results】 The association energy between four carboxylic acids and twenty-two terpenoid repellents is between 18 and 20 kJ/mol, and the association distance and angle are fluctuating from 2.0 to 2.5 Å and from 110° to 180°, respectively, which exactly fit the characteristics of hydrogen bonding interaction. Four obtained QSAR models were statistically satisfying, and the R² values of any one of these four parametric models were above 0.9. Every model contained the descriptors generated from attractant-repellent complex, showing a significant correlation between attractant-repellent association and the logCRR. 【Conclusion】 Hydrogen bonding associations with moderate strength exist between four carboxylic acids and terpenoid repellents, and such kinds of associations deeply affect the repellency. This study provides a preliminary support to the existence of attractant-repellent association and sets up a foundation for the research of repelling mechanism from a new perspective.

【Aim】 In order to develop new botanical aphicides, the joint aphidicidal action of alkaloids of Sophora alopecuroides L. and nicotine against Aphis craccivora Koch was evaluated systematically indoors and outdoors. 【Methods】 Toxicities of monomeric compounds to A. craccivora were tested by topical application method. Potter spray method was adopted to test the toxicity of aphicide formulation to A. craccivora. Constant spray method was used in the field efficacy trial, which was conducted according to the national standard. Moreover, pesticide formulation processing and the measurement of the joint aphidicidal action of alkaloids of S. alopecuroides and nicotine were performed using the conventional methods. 【Results】 The mixture of alkaloids of S. alopecuroides and nicotine showed significant synergism in the aphicidal activity aqainst A. craccivora, with the common-toxicity coefficient (CTC) value of 185.82 when the optimal ratio of total alkaloids to nicotine (13∶1, w/w) was used. Based on screening on solvent and emulsifier, 15.7% total alkaloids·nicotine (TAN) emulsifiable concentrate (EC) was developed, which consisted of 14.6% alkaloids of S. alopecuroides, 1.1% nicotine, 74.3% solvent and 10% emulsifier. Quality tests confirmed that this formulation met the requirements as a commercial product. Moreover, experiments in fields showed that 0.354 g/L 15.7% TAN EC maintained 85.91% control effect on Macrosiphum rosirvorum at 7 d after application. 【Conclusion】 The mixture of alkaloids of S. alopecuroides and nicotine can significantly increase the aphidicidal efficacy each other and has the potential to be further developed.

【Aim】 To investigate the biochemical mechanisms of defense responses of kidney bean to insect herbivory. 【Methods】 The activities of defense enzymes in kidney bean subjected to feeding by the western flower thrips (WFT), Frankliniella occidentalis (Pergande), mechanical wounding, and treatment of exogenous methyl salicylate (MeSA) and jasmonic acid (JA), respectively, were detected. 【Results】 The results showed that the peroxidase (POD) activities in kidney bean subjected to different treatments increased significantly compared to control. The POD activities induced by F. occidentalis feeding and mechanical wounding reached a peak at 72 h, while those induced by JA or MeSA reached a peak at 48 h. The proteinase inhibitor (PI) activities in kidney bean increased most obviously after thrips feeding. The activities of the key enzymes of JA pathway, lipoxygenase (LOX) and polyphenol oxidase (PPO), increased significantly after F. occidentalis feeding, mechanical wounding and JA induction, respectively, while MeSA did not induce their activities. The activities of phenylalnine ammonialyase (PAL), a key enzyme of SA pathway, increased firstly and then decreased in kidney bean subjected to thrips feeding or mechanical wounding. PAL activity induced by MeSA was significantly higher than the control at 24 h after treatment (P<0.05) but was similar to the control at other treatment time. JA induction failed to cause significant changes of PAL activity (P>0.05). Thrips feeding, JA induction, MeSA induction and mechanical wounding caused β-1,3-glucanase (PR-2) activities to increase significantly (P<0.05). 【Conclusion】 These results indicated that different treatments can induce distinct defense responses in kidney bean, and changes in defense enzyme activities are related to treatment types and treating time.

【Aim】 Athetis lepigone (Möschler) (Lepidoptera: Noctuidae) is a new insect pest in summer corn and causes serious damages to corn seedlings in China. It is very difficult to control this insect pest because its larvae hide beneath the straw and bran of winter corn in the field after harvest by combines. So it is important to study the attractant for A. lepigone larvae. 【Methods】 Y-tube olfactometer tests were conducted to investigate taxis responses of A. lepigone larvae to straw, bran, wheat bran, fried wheat bran and corn seedlings. The volatile components of fried wheat bran and wheat bran were analyzed by HS-SPME and GC-MS, and six compounds and eight blends were selected to further conduct the laboratory trapping. 【Results】 Among the five materials, fried wheat bran was the most attractive to A. lepigone larvae, and among the six volatile components, 2-heptanone (5 μg/μL) showed the strongest attractiveness to A. lepigone larvae, with the luring rate of 75.9%. Among eight blends, a three-component blend (2-heptanone＋benzaldehyde＋p-xylene) strongly attracted A. lepigone larvae with the luring rate of 72.7%, but its attractiveness effect was lower than that of 2-heptanone. 【Conclusion】 The results showed that 2heptanone has the strongest attractiveness to A. lepigone larvae. These results provide a basis for controlling the larvae of A. lepigone with field trapping.

【Aim】 Sinoxylon japonicum is a serious forest borer species. Since the first detection of its occurrence in Kunming, Yunnan Province in 1981, S. japonicum has been reported as occurring in more than 10 provinces and cities in China. Currently, it has caused substantial damages to the pagoda tree Sophora japonica in Beijing, Tianjin and Hebei. 【Methods】 In this study, we sorted the occurrence records of S. japonicum in chronological order, and further predicted its potential distribution using two ecological niche models, i.e., Maxent and GARP. 【Results】 The results indicate that S. japonicum is distributed sporadically in southern China, but in clusters in northern China. The distribution of this pest indicates an increasing trend from south to north and from east to west in China. We speculate that the outbreaks of S. japonicum in northern China might be due to the concentrated planting of S. japonica there, and its spreading might be due to the transportation of infested hosts. The results of ecological niche modeling suggest that large areas of China are suitable for S. japonicum. Potential distribution areas from north to south include western Liaoning, Beijing, Tianjin, Ningxia, Hebei, southern Shanxi, Shandong, Shaanxi, Jiangsu, Anhui, Hubei, Chongqing, Zhejiang, Jiangxi, Hunan, and northwestern parts of Sichuan and Guizhou. 【Conclusion】 In order to prevent S. japonicum from further spreading, the transportation of host plants between these areas should follow strict preventive regulations.  

【Aim】The study of sex ratio variation is important for understanding the causes and consequences of selective pressures. The pollinating fig wasps are widely used in researches on sex ratio and local mate competition (LMC) because of theoretical assumptions of their biological and ecological feature resemblance. Our study aimed to explore the mechanism of sex ratio adjustment and evolution in fig wasps. 【Methods】 We conducted controlled introduction experiments on Ficus semicordata in Xishuangbanna, and the first receptive day was defined firstly for each experimental fig by observing the behavior of the pollinator (Ceratosolen gravelyi). Then we tested the effects of foundress number, time interval of foundress entry and density of nonpollinating fig wasps (Sycoscapter trifemmensis) on clutch size (the number of adult wasps) and the offspring sex ratio of pollinating fig wasps, as well as the relationship between clutch size and the offspring sex ratio in each treatment. 【Results】 When foundress number increased, the mean clutch size per foundress significantly decreased (P<0.001) and the offspring sex ratio increased significantly (P<0.001), and the offspring sex ratio was negatively related to the clutch size per foundress for individual figs (P<0.05). As the foundress entry interval prolonged, the clutch size per foundress decreased and the offspring sex ratio (P=0.86) was less female-biased, and the similar trends were found between 2 foundresses (P=0.87) and 3 foundresses treatments (P=0.49). The density of non-pollinating fig wasps significantly reduced clutch size (P<0.001) and increased the offspring sex ratio of pollinating fig wasps (P<0.001), and a significantly negative relationship was found for individual figs between clutch size and the offspring sex ratio (P<0.001). 【Conclusion】 This study simulated the natural condition of interaction between figs and fig wasps, so the results can help us understanding the pattern and mechanism of sex ratio allocation in natural condition, and the evolution mechanisms of mutualistic symbiosis between figs and fig wasps as well.

【Aim】 The leafminer Chromatomyia horticola (Goureau) is one of the most important pests commonly found on vegetables in China. Up to now, there has been no systematic study of the morphology of the preimaginal (egg to pupa) stages of C. horticola. 【Methods】 We collected eggs, larvae of different instars and pupae from the field and reared in the laboratory. The morphological characteristics of the preimaginal stages of C. horticola from egg to pupa were observed and described systematically, and the larval instars were divided by measurement of the length of mouth hooks and cephalopharyngeal skeleton. 【Results】 We reported the pneustocera of egg for the first time for C. horticola which also for the family Agromyzidae. The larvae were divided into three instars based on the length of mouth hooks and cephalopharyngeal skeleton. The morphological characteristics of different larval instars were described. The precise method by measurement of skeleton structures and the fast method by observation of external morphology were established for discrimination of different larval instars of C. horticola. The development of the pupa was divided into five stages significantly based on morphological characteristics. 【Conclusion】 This study described the morphological characteristics of the preimaginal stages and divided the larval instars of the C. horticola, which provides fundamental information for the study of the morphology of preimaginal stages of agromyzids and the biology, physiology and control of C. horticola.

MicroRNAs (miRNAs) are a class of 18-24-nucleotide (nt), endogenously initiated, small noncoding, single stranded RNAs that can regulate target gene expression via either translational repression or mRNA degradation by combining with target mRNA complementarily. Honey bees are important eusocial and economic insects, and they have been the popular research objects at the international level. So far, 218 miRNAs in honey bees have been identified by a variety of biological technologies and registered. A series of studies on honey bee miRNAs showed that they are involved in regulating the embryonic development, caste differentiation, division of labor in workers and immunity defense. In this article, we reviewed the advances in researches of miRNAs in regulating caste differentiation between queen and worker bee, division of labor between nurse and forager, dancing behaviour, brain neurological function and immune defence in honey bees, aiming to provide references for further research.

 Neonicotinoid insecticides (neonicotinoids) are now the most widely used insecticides in the world. Acting systemically, they are taken by plants and then translocated to all tissues through vessel transportation. And they bind with high affinity to the nicotinic acetylcholine receptors (nAChRs) of insects, leading to neurotoxic effects. Honeybees are the most important pollinators worldwide with high economic and ecological value. Over the past few years, however, a global decline of pollinators, mainly honeybees, has caused great concern. Though the real reasons were unclear, the influences of neonicotinoids have been widely recognized. In this article, we reviewed the recent research on neonicotinoids and their lethal and sublethal impacts on honeybees. The policies of some countries and regions were also introduced. By summarizing the studies on the impacts of the neonicotinoids on honeybee health, we aimed to provide some references for further study in relevant areas in China.

【Aim】 To explore the effects of temperature on development and humoral immune defense of Tenebrio molitor larvae. 【Methods】 We investigated the larval duration, pupal weight, pupation rate of T. molitor reared at different temperatures (18, 22, 26 and 30℃). After immunization treatment (1 μL of physiological saline containing 1×104 cells of Escherichia coli was injected into the back of abdomen of each larva) and non-immunization treatment (physiological saline injected), the bacteriolytic and antibacterial activities in the hemolymph of T. molitor larvae reared at different temperatures were investigated via inhibition zone assay, and the phenoloxidase activity in the hemolymph was investigated by spectrophotometry. 【Results】 The developmental duration of T. molitor larvae decreased as temperature increased. There was a significant negative correlation between larval duration and temperature (P<0.0001), while the pupal weight (P=0.067) and the pupation rate (P=0.869) did not significantly differ at different rearing temperatures. The phenoloxidase, lysozyme and antibacterial activities in the hemolymph of immunized T. molitor larvae decreased with the increase of temperature. At different temperatures both phenoloxidase and antibacterial activities were extremely significantly different (P<0.0001), while the lysozyme activity was significantly different (P=0.013). 【Conclusion】 The results show that temperature has significant effects on the growth and development and the immune defense of T. molitor larvae. At lower rearing temperature the larval duration lengthens and the humoral immune defense significantly increases.

【Aim】 The western flower thrips , Frankliniella occidentalis (Thysanoptera: Thripidae), is a kind of invasive pest which damages greenhouse vegetables seriously in China. Our study aimed to evaluate the insecticide resistance level and offer the theoretical basis for controlling this pest. 【Methods】 Insecticide resistance in field populations of five localities (Beijing, BJ; Shouguang, Shandong, SG; Qingdao, Shandong, QD; Jinning, Yunnan, JN; Chenggong, Yunnan, CG) of F. occidentalis to 9 insecticides (spinosad, chlorpyrifos, abamectin, emamectin benzoate, cyhalothrin, chlorfenapyr, methomyl, imidacloprid and acetamiprid) from China were determined by Munger cell bioassays. The synergisms of mixed-functional oxidase inhibitor piperonyl butoxide (PBO), glutathione S-transferase inhibitor diethyl maleate (DEM) and carboxylesterase inhibitor S,S,S-tributyl phosphorotrithioate (DEF) with spinosad, imidacloprid and emamectin benzoate were determined by the same bioassay method with these field populations. 【Results】 The bioassay results showed that there was a significant high-level resistance to spinosad in BJ, JN and CG populations of F. occidentalis (34.45, 47.45, and 64.45 times, respectively).The JN population revealed a medium-level resistance to methomyl and emamectin benzoate (16.58 and 11.03 times, respectively). The CG population also had a medium-level resistance to most insecticides including emamectin benzoate, acetamiprid, imidacloprid, abamectin, and chlorfenapyr (24.17, 21.69, 20.05, 16.45, and 10.31 times, respectively). Similarly, a medium-level resistance to acetamiprid and imidacloprid was found in the QD population (17.70 and 12.49 times, respectively). However, the SG population had no resistance to any of the insecticides. The results of synergism bioassay showed that significant synergisms of PBO with imidacloprid and emamectin benzoate were found in all field populations. There were synergism of DEM with imidacloprid in CG, SG and QD populations and with emamectin benzoate in BJ, CG and SG populations. Furthermore, we found synergism of DEF with imidacloprid in CG, JN and QD populations and with emamectin benzoate in BJ, CG and JN populations. However, PBO, DEM and DEF showed no significant synergism with spinosad in the all field populations. 【Conclusion】 These results suggest that spinosad and other insecticides should be used alternately to exterminate field populations of F. occidentalis, and adding enzyme inhibitors to emamectin benzoate and imidacloprid can enhance the effect on controlling this pest.