In subtropical parts of Indian subcontinent, autumn is cold and dry while spring is wet and humid and ectothermic drosophilids are expected to evolve desiccation resistance to cope with drier climatic conditions. Drosophila jambulina exhibits color dimorphism. Previous studies have described that in tropical populations of D. jambulina, body color polymorphism is maintained through humidity changes as opposed to thermal melanism and seasonal changes in the frequency of body color morphs in this tropical species supports melanism-desiccation hypothesis. But the mechanistic bases of such climatic adaptations in two body color morphs of D. jambulina are largely unknown. We tested the hypothesis that divergence in the physiological basis of desiccation-related traits is consistent with body color morph-specific adaptations to climatic conditions, for which we examined the response of water balance to relative humidity (RH), temperature, and their interaction in D. jambulina, using two body color morphs that had been allowed to rear at low (40%) or high humidity (80%) at 17℃ and 25℃. We found that, at low RH, dark body color morph had significantly greater physiological and desiccation trait values than light body color morph at both the temperatures. A comparative analysis of water budget of the two body color morphs showed that higher water content, reduced rate of water loss and greater dehydration tolerance confer higher desiccation resistance in dark morph of D. jambulina at low RH. We found that carbohydrates act as metabolic fuel during desiccation stress in both the morphs, but a higher level of stored carbohydrates was evident in dark morph at low humidity. Further, total energy budget differ significantly between these two body color morph at two humidity. Thus, body color morph-specific divergence in water-balance-related traits in D. jambulina is consistent with their adaptations to wet and dry habitats.

 Cold acclimation usually alters gene expression in insects. Extensive studies from the genomic level will help to fully understand the molecular mechanism of insects in response to cold. In order to get the further information about the up-regulated attacin gene (MpAttacin1) obtained from the transcriptomic data generated at 4℃ from the desert beetle Microdera punctipennis, and to analyze the responsive expression of this gene induced by low temperature, MpAttacin1 was characterized by bioinformatic analysis. Real-time quantitative PCR was performed to detect the mRNA level of MpAttacin1 at low temperatures. The results showed that the obtained MpAttacin1 cDNA is 523 bp with an open reading frame of 456 bp and the 5′-untranslated region of 66 bp. It encodes a polypeptide of 151 amino acid residues containing a putative signal polypeptide of 17 amino acids at the N terminal end. Homology analysis showed that the encoded product of this gene shares 30%-40% identity at the amino acid level with attacins from other insects of Lepidoptera, Diptera, and Coleoptera. The phylogenetic tree generated by Neighbor-Joining method indicated that MpAttacin1 and attacin proteins from other coleopterans are descended from a common ancestor, and they belong to Attacin_C superfamily. Analysis of realtime quantitative PCR showed that the expression of MpAttacin1 presented a stress-response tendency when stressed at both 4℃ and -4℃, increasing first and then decreasing. However, there were differences in their responsive time and strength between these two treatments. The mRNA level of MpAttacin1 at 4℃ for 5 h and 9 h was 2.3- and 3.8-fold as high as that of the control at room temperature, respectively, while that at -4℃ for 7 h and 9 h was 2.4- and 1.5-fold as high as that of the control, respectively. The results suggest that in addition to the typical function as an anti-microbial peptide, attacin may also be involved in cold adaptation in insects.

In order to evaluate the biological activities of wintergreen oil and cinnamon oil against mosquitoes, repellent and fumigant activities of wintergreen oil and cinnamon oil against Culex pipiens pallens were investigated via immersion method, “Y”-tube olfactometer and fumigation, respectively. The results showed that cinnamon oil and wintergreen oil had high larvicidal activity against C. pipiens pallens larvae, with the LC₅₀ values (24 h) of 71.87 mg/L and 102.83 mg/L, respectively. Wintergreen oil and cinnamon oil exhibited good repellent activity against C. pipiens pallens adults (percent repellency>80%) at the dosage of 0.5 μL within 20 min. Wintergreen oil had excellent knockdown activity against C. pipiens pallens adults at the dose of 12 μL/L with the KT₅₀ value of 3.97 min, and cinnamon oil exhibited high fumigation activity against C. pipiens pallens adults with the LC₅₀ value of 0.31 μL/L after 5 h exposure. The mixture (1∶1, v∶v) of wintergreen oil and cinnamon oil performed both rapid knockdown and high lethal toxicity against C. pipiens pallens adults, suggesting that they have a synergistic effect. Wintergreen oil and cinnamon oil showed high larcicidal activity against C. pipiens pallens larvae and good repellent and fumigation activities against female C. pipiens pallens adults, suggesting that wintergreen oil and cinnamon oil could be exploited as potential botanical mosquito control agents.

Circularly polarized light is rare in the terrestrial environment, and cuticular reflection from scarab beetles is one of the few natural sources. The scarab beetle Anomala corpulenta Motschulsky possesses a brilliant metallic appearance, and selectively reflects left circularly polarized light as other jewel beetles. To clarify the capacity of responses of A. corpulenta to circularly polarized light, indoor behavior, field selection and electroretinogram (ERG) responses of A. corpulenta to circularly polarized light were studied in this experiment. The indoor behavior research showed that the phototaxis responses of A. corpulenta to left and right circularly polarized light were significantly lower than those to unpolarized light, while the photophobism responses were significantly greater than the phototaxis responses to unpolarized light, and both the phototaxis and photophobism responses of A. corpulenta to left circularly polarized were greater than those to right circularly polarized light. The field selection test results showed that the selection of A. corpulenta to left and right circularly polarized light was obviously lower than that to unpolarized light, and the responses selecting to right circularly polarized light were stronger than that to left circularly polarized light. Electrophysiological studies showed that left and right circularly polarized could trigger ERG responses of A. corpulenta compound eyes as unpolarized light, and had no obvious difference among them. These results indicate that A. corpulenta is a metallic iridescent species that selectively reflects left circularly polarized light and possesses a brilliant metallic appearance. It can perceive and distinguish left and right circularly polarized light, and circularly polarized light can trigger ERG responses of A. corpulenta compound eyes as unpolarized light. These results support the hypothesis that A. corpulenta has polarization vision and sensitivity to circularly polarized light.

 Fruit fly is one of the most serious quarantine pests. In recent years, Bactrocera dorsalis Hendel (oriental fruit fly), B. papayae Drew & Hancock (papaya fruit fly) and B. correcta (Bezzi) (guava fruit fly) were intercepted frequently in the port of entry. In this study, we detected and compared the heat tolerance of eggs, the 1st instar and 3rd instar larvae of the three fruit flies at temperatures ranging from 44℃ to 47℃ using a hot water immersion technique. The species with the highest heat tolerance were determined through thermal death kinetic model and activity energy. The results showed that there was a positive relation between the mortalities of eggs, the 1st and 3rd instar larvae of all the three species and the exposure time at the experimental temperature. The 0.5 order kinetic model fitted best to predict the LT_99.9968 lethal time at all the treatment temperatures. The order of heat tolerance stage for all the three species was egg>1st instar larva>3rd instar larva. The thermal death time (TDT) curves showed that the egg of B. correcta had the highest heat-resistance among all life stages of three species. This study provides an experimental basis for the development of heat quarantine treatment indicators of fruit flies.

Aphid infestation is one of the most important factors that affects the yield and quality of potato (Solanum tuberosum), whereas polyphenol oxidase (PPO) is a significant anti-insect trait in plants. In order to clarify the interaction between potato and peach aphid (Myzus persicae) after potassium supply, the changes of PPO activity in patato leaves in four treatments, i. e., the control (no potassium supply, no aphid feeding), aphid feeding, potassium supply and aphid feeding plus potassium supply, were assayed using colorimetry, iTRAQ technique and Western blotting. The results indicated that the population size of peach aphid decreased significantly after potassium supply compared with that of the control group in the development processes. Potassium supply of 6 g/seedling had the highest inhibitory effect on the growth of peach aphid populations. The PPO activity in potato leaves increased by 44% and 67% after potassium supply of 6 g/seedling and aphid feeding plus potassium supply, respectively. LC-MS/MS analysis showed that the expression level of PPO protein was up-regulated in varying degrees after the potato leaves were subjected to aphid feeding, potassium supply and aphid feeding plus potassium supply. Western blotting results showed that the relative expression level of PPO increased significantly in treatments of potassium supply and aphid feeding plus potassium supply, and presented the highest relative expression level in aphid feeding plus potassium supply treatments. The results suggest that potassium supply and aphid feeding plus potassium supply may enhance potato resistance to aphids due to, at least in part, the induction of PPO activity in its leaves.

Mythimna separata (Walker) is a vital pest insect in China. In order to identify the parameters of seasonal migratory behavior of M. separata (Walker) in Northeast China, long-term observation was carried out by vertical-looking radar (VLR) and light traps in Jilin province in 2005, in combination with analysis of large-scale wind systems and trajectory simulation based on GIS. The results showed that migration of M. separata moths only occurred on a few nights during each of three distinct migration periods; they flew at obviously different altitudes depending on season and time of night, and their migratory behavior was significantly influenced by meteorological conditions, especially the large-scale atmospheric circulation. The long-distance migration was windborne, and flights of M. separata moths could be observed throughout the night. The flying altitude in spring was mainly 300-600 m, while that in autumn was relatively low, mainly below 500 m. Radar echoes in summer were obvious in layers, indicating that the migrants were sometimes concentrated into two or more layers, mainly in 500 and 700 m, with a maximum height of up to 1 000 m. Trajectory analysis showed that on May 29 and June 1, M. separata populations flying over the radar station originated from the southwest, probably from Shandong province. In mid-July, however, these populations were locally landed and showed relatively short-distance dispersal under the influence of convective weather. On September 11, M. separata populations originating from the Hulun Buir region of Inner Mongolia were observed to fly on northwesterly winds to the southeast of Jilin province. The results provided technical support for the effective prevention and control of armyworm in Northeast of China.

To ascertain the biological characteristics of the small brown planthopper, Laodelphax striatellus (Fallén), in Nanchang, Jiangxi, East China, the annual life history, the influences of temperature on development and reproduction, sex ratio and its overwintering biology were systematically investigated under laboratory and natural conditions. The results showed that this species exhibit mixed voltinism from 4 to 7 generations per year. Between 18 and 32℃, and 18 and 28℃, the egg duration and the nymphal duration gradually declined with increasing temperature, respectively. However, the nymphal duration was significantly longer at 30 and 32℃ than at 28℃. The duration of overwintering nymphs ranged from 143 to 187 d. The lower development thresholds of egg and nymph were 10.17℃ and 7.51℃, respectively. In the outdoors, the developmental duration of the 4th generation nymphs hatched at high temperature of mid-July had significantly delayed, showing high-temperature induced summer quiescence. Between 18 and 28℃, the pre-oviposition period gradually shortened with increasing temperature; however, the pre-oviposition period was longer at 30℃ than at 26 and 28℃. The oviposition period was the longest at 22℃, and the shortest at 30℃. The mean longevity of adults was the longest at 20-24℃. The number of nymphs produced per female was the highest at 28℃. Under both laboratory and natural conditions, the sex ratio is close to 1∶1. Between 18 and 32℃, the number of long-winged adults (macroptery) was significantly higher than that of short-winged adults (brachyptery). In the outdoors, the number of the brachytery was significantly more than that of the macroptery in the overwintering generation and the 6th generation, whereas the number of the macroptery was significantly more than that of the brachytery in other generations. Under natural conditions, winter diapause had already occurred in some individuals that hatched in mid-September, and all individuals that hatched after mid-October entered winter diapause. This planthopper overwintered as 1-5 instar nymphs. This study provides the basic data for the prediction of L. striatellus occurrence and the effective prevention and control of this pest.

The fruitpiercing moth, Oraesia emarginata (Fabricius), is an important pest for fruits and can be used as model insect for olfactory study, because its larvae and adults feed on different host type. In order to understand the morphological and biological characteristics of O. emarginata, its external morphological characters, developmental duration and the circadian rhythm of different developmental stages were studied through artificially feeding in the controlled conditions and monitoring with infrared camera. The results showed that different larval instars could be differentiated by body color, the color, location and number of spots in the body, and the number of abdominal feet. The genital pore in the pupae, and moth antennae could be used for sex identification. The life time of O. emarginata was 53.18±1.70 d and the survival rate was 63.62%±2.15% under laboratory conditions. Compared with other stages, larva had the longest developmental duration and lowest survival rate while the egg had the shortest developmental duration and highest survival rate. Male moths lived significantly longer than female moths (P=0.008). The developmental duration of the 6th instar larva (5.29±0.15 d) was significantly longer than that of other larval instars (P<0.001). The body length and body weight of larvae in the middle time of an instar were significantly larger than those before ecdysis and after ecdysis for the same instar (P≤0.037). There were no significant differences in the body length and body weight between the larvae after ecdysis of a later instar and the larvae in the middle time of the former instar (P≥0.106). The proportions of hatching, ecdysis and pupation of larvae during light period were higher than those during dark period. However, the rates of moths in flight and oviposition under dark condition were higher than those under light condition. The flight frequency of moths decreased when the dark time prolonged and the moths in flight during light period were mostly found in the first hour of light period. The moth copulation was only found at 3-5 h after dark. These results will not only help to design more efficient pest control methods, but also provide knowledge for using the insect as a model for olfactory study.

The tobacco aphid, Myzus persicae (Hemiptera: Aphididae), is an important pest on cultivated crops worldwide. In order to evaluate the morphological variations of M. persicae populations from eighteen geographical areas in China, such morphological characters as body length, body width and femur length, and Q value of M. persicae were measured and analyzed using ANOVA and Mantel test based on the relationship between the Euclidean distance and the geographical distance or altitude. The ratios of every morphological character to body length were used to carry out hierarchical cluster analysis (HCA) and principal component analysis (PCA). The results showed that there were significant differences in morphometrics among certain geographical populations. The results of HCA and PCA indicated that among the 18 geographical populations, the biggest difference existed between the population from Zhenfeng of Guizhou province and other populations, while the least differences were observed among the populations from Nanniwan of Shaanxi province, Cili of Hunan province, Qiaocheng of Anhui province and Wulong of Chongqing city; the differences among the other populations were between the both. The Mantel Test revealed that there was no significant correlation between the Euclidean distance and the geographical distance or altitude. The morphological differentiation of M. persicae is not in conformity with the geographical isolation mode. Geographical and climatic conditions have influences on the morphological variations of M. persicae populations, which are caused by many factors. The specific mechanisms of morphological differentiation, however, are not clear.

Three species of the genus Erianthella Descamps, 1975 are described and illustrated, including two new species Erianthella lini sp. n. and Erianthella chani sp. n. The new species E. chani sp. n. is similar to E. formosana Shiraki, 1910, but differs from the latter by the R vein of tegmen with 1 branch, M area of tegmen with intercalary vein, and tegmen with 1 small white spot. The new species E. lini sp. nov. is similar to E. chani sp. nov., but differs from the latter by the R vein of tegmen without branch, M vein of tegmen with 3 branches, and M area of tegmen without intercalary vein. A key to species of the genus is given.

Bursicon, a kind of neuropeptide hormone, regulates insect cuticle sclerotization and wing expansion. Bursicon is a heterodimer protein which consists of two cystine knot proteins, BURS and PBURS. BURS and PBURS are conserved in structure and evolution, and the amino acid sequences of both contain 11 conserved cystines. Bursicon is synthesized by thorax and abdomen ganglions. Once released into hemolymph, bursicon binds with its receptor, LGR2, and then activates cAMP/PKA pathway, which activates tyrosine hydroxylase (TH) by phosphorylation. The activated TH transforms tyrosine into DOPA, resulting in insect cuticle sclerotization. At the same time, cAMP/PKA promotes apoptosis of wing hypodermal cells and causes wing expansion. BURS or PBURS homodimers also regulate insect immune reactions by activating the transcriptional factor Relish via IMD pathway. In this article, the progress in the molecular characteristics, molecular mechanisms and functions of bursicon was reviewed in order to provide a reference for further elucidating bursicon action in insects.

In recent years, the use of solid-phase micro-extraction and other modern technologies has significantly promoted the advances in the field of cuticular hydrocarbons of termites. So far, cuticular hydrocarbon components of 29 species of termites have been identified. The reported termites belong to Kalotermitidae, Rhinotermitidae, Termopsidae and Termitidae, respectively. The main compositions of cuticular hydrocarbons are n-alkanes, methyl-branched alkanes and a small amount of alkenes. Termite cuticular hydrocarbons have not only family- and genus-specific to some degree, but many kinds of termites also contain species-specific cuticular hydrocarbon components, suggesting that cuticular hydrocarbons of termites can be used for species identification. As to the role of cuticular hydrocarbons in nestmate recognition, most of the researches in lower termites got supportive results, meaning that they can be used for nestmate recognition. However, some researches show that cuticular hydrocarbons are not the only cue of nestmate recognition. The finding of the correlation between cuticular hydrocarbons and caste differentiation of termites is an important progress in recent years. The seasonal shift in proportions of hydrocarbons correlates with the production of alates in some species of termites. In other species, the reproductives contain some characteristic compositions. Changes in the quantity of cuticular hydrocarbon components in the reproductives are related to their reproductive status. The results suggest that these components may play an important role in caste differentiation of termites. As a new research direction on the mechanisms of caste differentiation and maintenance, cuticular hydrocarbons are worthy of further research and exploration.

Next-generation sequencing (NGS) techniques provide the rapid, highthroughput and cost-effective approach to genomics research, which has profoundly transformed the research on current biology. In recent years, NGS has greatly promoted the development of insect transcriptomics, especially for insects without reference genome sequences. Since 2008, insect transcriptomes of 68 species belonging to seven orders have been sequenced by using NGS, of which 22 species from six orders were sequenced by Chinese scientists. Currently, insect transcriptomics based on NGS mainly focus on new gene discovery, development of molecular markers, and gene expression profiling, providing the opportunity to reveal gene function related to insect life activities, phylogeny and evolution, and the interaction between insects and other organisms. In this article, we summarized the current results of insect transcriptomics research, analyzed the development trends in the future, discussed the limitations of insect transcriptomics research based on NGS (e. g., limited taxa, and relatively low-accuracy sequencing), and proposed what we need to keep in mind before launching insect transcriptomics studies, including specific scientific questions, appropriate research strategies, low-cost high performance, and efficient methods to utilize transcriptomic information. For the future prospects, we suggest that it is necessary: (1) to sequence more insect transcriptomes using NGS, paying significant attention to the typical insects from other insect orders and unique ecological environment; (2) to develop hardware and software for transcriptome data storage and analyses; and (3) to use NGS to study insect transcriptome with caution and take full advantage of the genetic information of sequenced insect transcriptome.

The small brown planthopper, Laodelphax striatellus (Fallén), is an important piercing-sucking pest of many economic Poaceae plants. Salivary glands play a key role in plant feeding for piercing-sucking pests because the secreted saliva help them pierce and digest plants and detoxify secondary metabolites. The detoxification system of insects is mainly composed of cytochrome P450 monooxygenase (P450), glutathione S-transferase (GST), and carboxylesterase (CarE). In order to clarify the expression profiles of detoxification enzyme genes in salivary glands of Laodelphax striatellus, the transcriptome of adult salivary glands was sequenced, de novo assembled and annotated, and phylogenetic analysis of the three detoxification enzyme families among L. striatellus, Acyrthosiphon pisum, and Apis mellifera was conducted in this study. The results showed that 9 glutathione S-transferases (GST) genes, 22 carboxylesterases (CarE) genes, and 39 cytochrome P450 monooxygenases (P450) genes were found expressed in salivary glands. Phylogenetic analysis showed that most of CarEs take part in dietary/detoxification and hormone/semiochemical processing while few CarEs are related to neuro/development in L. striatellus salivary glands. The number of P450 genes expressed in L. striatellus salivary glands is fewer than that in the genomes of A. pisum and A. mellifera, and only CYP6 and CYP4 genes were expressed in L. striatellus salivary glands. GSTs were the most conserved in the three insects. These results underpin the researches of adaptation to host plants and insecticides of L. striatellus.

Aim】 In order to provide theoretical basis for forecast and scientific control of Apolygus lucorum (Meyer-Dür), we surveyed the population dynamics of A. lucorum and its natural enemies in the pear orchards. 【Methods】 The population dynamics of A. lucorum and its natural enemies were studied by green sticky traps and visual investigation from 2012 to 2013 in a pear orchard of Institute of Forestry and Pomology, Beijing Academy of Agriculture and Forestry Sciences. 【Results】 The green sticky traps results showed that A. lucorum had two occurrence peaks, and the first peak was much higher than the second. The main peaks of A. lucorum appeared in late May to middle of June. However, the visual investigation indicated that A. lucorum had two occurrence peaks in mid May and late May in 2012, but had only one occurrence peak in late May in 2013. The peak of natural enemies mainly happened in early June to late June in 2012 and 2013. The main natural enemies were predators, including spiders and insects. The natural enemy insects included 7 species belonging to 3 families of 3 orders. The dominant predators were spiders, Chrysoperla sinica (Tjeder), Harmonia axyridis (Pallas) and Propylea japonica (Thunberg). 【Conclusion】 There are obvious pursuing relationships in time and quantity between green plant bugs and their natural enemies.