【Aim】 This study aims to investigate the functions of the ATP synthase b subunit gene in the rice brown planthopper (BPH), Nilaparvata lugens by RNAi and to explore the potential using the gene as a target to control this pest. 【Methods】 The full-length cDNA of ATP synthase b subunit gene was cloned from the BPH reared on rice variety TN1 by RACE according to the sequence information available in the transcriptome data previously obtained by our laboratory. The expression profiles of this gene in different developmental stages and different tissues of the 5th instar nymphs of N. lugens were detected with real-time quantitative PCR, and the RNAi experiments of the gene were carried out with the 2nd instar nymphs of N. lugens by using feeding method. 【Results】 The full-length cDNA of the ATP synthase b subunit gene of the BPH named ATPSb (GenBank accession number: MF973493) was successfully cloned. It contains an ORF of 843 bp, encoding a protein of 280 amino acid residues. Real-time quantitative PCR showed that the ATPSb gene was highly expressed in the 1st and 2nd instar nymphs, and its relative expression level decreased with the developmental stage. The mRNA level of ATPSb was higher in male adults than that in female adults. In the 5th instar nymphs, the mRNA level of ATPSb in the thorax was the highest among different tissues, while relatively low in the head, midgut, ovary and fat body. The RNAi results showed that the mRNA level of ATPSb was significantly decreased in the dsATPSb treatment group from the 6th day, and the RNAi treatment led to distinct mortality of the BPH nymphs. At 18 d after RNAi, the survival rate in the control group kept 80%, while no individual survived in the dsATPSb treatment group. 【Conclusion】 The results suggest that the ATPSb gene is essential to the survival of the BPH, and the RNAi of ATPSb shows an effective inhibition of the BPH. ATPSb may serve as a potential target gene for BPH control.

 【Aim】 This study aims to clone three pheromone binding protein (PBP) genes from the litchi fruit borer, Conopomorpha sinensis, and to analyze their sequences and expression characteristics, so as to provide essential basis for better use of sex pheromone for control. 【Methods】 The full-length cDNA of three PBP genes were cloned from the antennae of C. sinensis adults by transcriptome and RACE-PCR technique after extracting total RNA. The putative amino acid sequences were analyzed by bioinformatics software. The software I-TASSER was used to simulate 3D models, the software TM-align was used in protein homology modeling and the software COACH was used to speculate the binding sites. The expression profiles of the three genes in different developmental stages (larval and pupal stages), and different tissues of the 3 d-old female and male adults (antennae, head without antennae, thorax, abdomen, legs and wings) were analyzed by real-time PCR. 【Results】 Three PBP genes were cloned from the antennae of C. sinensis adults. They were named CsinPBP1, CsinPBP2 and CsinPBP3, and deposited under GenBank accession numbers MF093145, MF093146 and MF093147, respectively. Bioinformatic analysis revealed that the encoded proteins of the three genes have typical characteristics of odor binding proteins. Phylogenetic analysis revealed that CsinPBP1 has 72% amino acid sequence identity with PBP of Yponomeuta cagnagellus, CsinPBP2 has 55% amino acid sequence identity with PBP1 of Plutella xylostella, and CsinPBP3 has 39% amino acid sequence identity with PBP3 of Sesamia inferens. Software simulation analysis revealed that the 3D structures of CsinPBP1, CsinPBP2 and CsinPBP3 were the most similar with GOBP2 of Bombyx mori (PDB: 2wc6A), PBP1 of Amyetois transitetella (PDB: 4inxA) and PBP of B. mori (PDB: 2p70A), and were predicted to have 10, 7 and 8 binding sites, respectively. Expression profiling revealed that the three genes were only expressed in adult antennae, but neither in larval and pupal stages nor in other adult tissues including the head without antennae, thorax, abdomen, legs and wings. The relative expression levels of CsinPBP1, CsinPBP2 and CsinPBP3 in the antennae of male adults were 1.94, 28.19 and 32.94 times as high as those in the antennae of male adults, respectively. 【Conclusion】 Three PBP genes were cloned in C. sinensis. Their sequence and expression analysis suggest that they are related to sex pheromone sensing in males.

【Aim】 The odorant binding proteins (OBPs) of insects are closely related to olfactory recognition and play a key role in the successful delivery of fat-soluble odorant molecules in the lymph nodes of the antennal sensory receptors to the olfactory receptors. In order to understand the roles of OBPs in olfactory recognition and to lay foundation for studying the molecular mechanisms of olfactory transmission in Bactrocera minax, an OBP gene was cloned and its expression profiles were analyzed. 【Methods】 The full-length cDNA sequence of OBP gene was cloned from B. minax using RT-PCR and RACE techniques, and subjected to bioinformatics analysis. The recombinant expression vector pET28a(+)-BminOBP25 was constructed and transformed into Escherichia coli BL21 (DE3). The recombinant protein was identified by SDS-PAGE and Western blotting. The expression profiles of OBP gene in different tissues of B. minax adults were detected by quantitative real-time PCR (qPCR). 【Results】 An OBP gene was cloned from B. minax and named BminOBP25 (GenBank accession no.: MH181875). Its ORF is 447 bp in length encoding 148 amino acids with a predicted molecular weight of 17.5 kD. The encoded protein has typical six conserved cysteines and six α-helices. The recombinant expression vector pET28a(+)-BminOBP25 was constructed and the target protein was stably expressed in host bacteria in the form of 6×His tag fusion protein after IPTG induction. qPCR analysis showed that BminOBP25 mRNA was expressed in antennae, head (without antennae), thorax, abdomen, leg, wing and ovipositor of adults, with higher expression levels in antenna, head (without antennae), leg and ovipositor.【Conclusion】 BminOBP25 has high transcriptional activity in antennae, heads, legs and ovipositors of B. minax adults, suggesting that BminOBP25 may also have physiological functions in non-olfactory tissues, and especially may play important roles during the selection of insect feeding and spawning sites. Its functions need further study. In this study, the prokaryotic expression of BminOBP25 was achieved, laying a foundation for further study of its functions.

【Aim】 This study aims to explore the function of galectin in Apis cerana cerana and its interaction with the honeybee virus. 【Methods】 Galectin gene was amplified from A. cerana cerana by RT-PCR using the extracted total RNA as the template, and then the sequence and structural characteristics of deduced amino acids were analyzed by using bioinformatics tools. The codons of the galectin gene were optimized based on the codon bias of Escherichia coli, and the recombinant protein was produced in E. coli and purified by affinity chromatography. The binding activities of the recombinant protein with Chinese sacbrood virus (CSBV), Chronic bee paralysis virus (CBPV) and Deformed wing virus (DWV) were analyzed by far-western blotting. 【Results】 A galectin gene was cloned from A. cerana cerana and named AcGalectin (GenBank accession no: MG557559), and its full-length cDNA is 1 473 bp in length. AcGalectin has a stable spatial structure containing a Gal-bind_lectin domain. The phylogenetic tree constructed based on the amino acid sequences from AcGalectin and the previously reported galectins indicated that galectins form two clusters, one related to galectins from the Hymenoptera, and the other related to galectins from other insects. The codon-optimized AcGalectin gene could be highly expressed in host bacteria BL21 (DE3), and the purified recombinant AcGalectin protein could bind with CSBV and CBPV, but not with DWV. 【Conclusion】 The results indicate that AcGalectin can bind with CSBV and CBPV, and this lays a foundation for the further study on the function of AcGalectin in the process of CSBV and CBPV infections.

 【Aim】 The objective of this study is to investigate the diversity and prevalence patterns of Wolbachia in populations of the Asian corn borer, Ostrinia furnacalis in Xinjiang, northwestern China. 【Methods】 Wolbachia infection rates in 15 geographical populations of O. furnacalis collected from Xinjiang Uygur Autonomous Region were detected, and six genes including wsp, ftsZ, gatB, coxA, hcpA and fbpA were subcloned and sequenced from each infected individual. Phylogenetic analysis and sequence typing of Wolbachia strains infecting O. furnacalis were performed based on wsp sequences and by multilocus sequence typing system (MLST), respectively. 【Results】 The Wolbachia infection rates in the 15 O. furnacalis populations ranged from 0 to 40.0%, with an average infection rate of 11.1% (no infected individual was detected in five populations). Phylogenetic trees based on wsp sequences and MLST allelic profiles indicated that two Wolbachia strains, i.e., wOfur1 and wOfur2, infected O. furnacalis populations in Xinjiang, which were assigned to the supergroup A and supergroup B, corresponding to MLST sequence type ST352 and ST37, respectively. Among the tested populations, four populations, i.e., populations from Changji (CJ), Fukang (FK), Manasi (MNS) and Qitai (QT), were infected with both strains, and six populations, i.e., populations from Hotan (HT), Korla (KEL), Yarkant (SC), Shule (SL), Urumqi (UM) and Xinhe (XH), were only infected with wOfur2. The average infection rates of wOfur1 and wOfur2 were 1.2% and 10.3%, respectively. Superinfection was found in MNS population tested. wsp and MLST clustering showed a closely genetic relationship between wOfur2 and several Wolbachia strains which had been proved to induce cytoplasmic incompatibility and male-killing to their insect hosts. 【Conclusion】 The two Wolbachia strains wOfur1 and wOfur2 show distinct differences in the infection rate and prevalence pattern in O. furnacalis populations in Xinjiang. Infection with wOfur2 is more frequent and widespread than that with wOfur1 in O. furnacalis populations.

【Aim】 This study aims to screen the chemical attractants and repellents produced by non-host plants, which are potentially used for developing ‘push-pull’ strategy for controlling a common tea pest, Ectropis grisescens. 【Methods】 The behavioral and electroantennogram (EAG) responses of male and female adults of E. grisescens to essential oils from three non-host plants including Chenopodium ambrosioides, Mentha spicata and Artemisia annua were evaluated by using Y-tube olfactometer and EAG. 【Results】 Both sexes of E. grisescens adults showed EAG response to the essential oils from C. ambrosioides, M. spicata and A. annua in a dose-dependent manner, with the antennal response strengthening first and then decreasing with the concentration of essential oil, and reaching the maximum at the concentration of 1, 100 and 100 mg/L, respectively. Male adults showed slightly greater EAG response than females to the essential oils from C. ambrosioides and M. spicata, while their response to the essential oil from A. annua was opposite. The results of behavioral response tests showed that both sexes of E. grisescens adults displayed non-significant taxis to the essential oils from C. ambrosioides and A. annua and significantly negative taxis to the essential oil from M. spicata. 【Conclusion】 E. grisescens adults show significant EAG responses to the essential oils from the non-host plants C. ambrosioides, M. spicata and A. annua, and the essential oil from M. spicata has repellent activity against E. grisescens.

【Aim】 This study aims to explore the volatiles from the host plant Juglans mandshurica, which affect the behavioral response of the brown mulberry longhorn beetle Apriona germari, and to provide a theoretical basis for screening plant-originated attractants or repellents of this insect. 【Methods】 Volatiles released from J. mandshurica in different damaged states ［healthy (CK), and feeding, oviposition and boring damage by A. germari］ were collected by using dynamic headspace adsorption, and those causing electrophysiological and behavioral responses in A. germari were identified by gas chromatography-mass spectrometry (GC-MS), gas chromatography-electrophysiological antennal detecting system (GC-EAD) and Y-tube olfactometer. 【Results】 In different damaged states, the main volatiles released from J. mandshurica included terpenes and aromatic compounds, and significant differences existed in the relative contents of several components of them. There were one or several unique volatile components in each damaged state. However, A. germari adults only had significant electrophysiological responses to six volatiles, including (1R)-(+)-alpha-pinene, cis-3-hexenyl acetate, nonanal, α-terpineol, 2-ethylhexyl acrylate and hexadecane, but had no responses to the other volatiles. Female adults had the strongest electrophysiological responses to nonanal, while male adults had the strongest electrophysiological responses to cis-3-hexenyl acetate. The olfactory reaction showed that 2-ethylhexyl acrylate had a significant attractivity to the female adults of A. germari (P＜0.05), while cis-3-hexenyl acetate had an extremely significant attractivity to the male adults (P<0.01). And nonanal had a significant attractivity to both female and male adults (P＜0.05), while α-terpineol had a significant repellent activity to them (P＜0.05). 【Conclusion】 These results indicate that cis-3-hexenyl acetate, nonanal and 2-ethylhexyl acrylate show strong attractivity to A. germari adults, while α-terpineol shows good repellent activity.

 【Aim】 This study aims to clarify the relationship between feeding preference and taxis behavior of Holotrichia oblita adults on three plant species. 【Methods】 The taxis and feeding amount of H. oblita adults to Chinese elm (Ulmus parvifolia), wild cotton (Abutilon theophrasti), and castor-oil plant (Ricinus communis) were measured by the scanned leaf image device and Y-tube olfactometers. The volatiles from the three plants were collected by the dynamic headspace volatile collection method and identified by gas chromatography-mass spectrometer (GC-MS), and the active volatile compounds were screened by Y-tube olfactometer. 【Results】 The taxis of H. oblita to R. communis was significantly higher than that to U. parvifolia and A. theophrasti (P<0.05). There was no significant difference in taxis between to U. parvifolia and to A. theophrasti. However, H. oblita adults showed the highest foliar feeding amount to U. parvifolia among these three plants, and displayed nearly equal taxis to A. theophrasti and R. communis. Moreover, no significant difference in foliar feeding amount was found between female and male adults of H. oblita (P>0.05). GC-MS analysis showed that plant volatile compounds in the three plants were largely different. In the olfactory response test with Y-tube olfactometer, (Z)-3-hexenyl isobutyrate, dibutyl phthalate, (Z)-3-hexenyl acetate, linalool, phenol, methyl salicylate, and β-caryophellen at the concentration of 10 μg/μL were found to be more attractive to H. oblita as compared with the control (hexane), while 3-carene, (E)-2-nonenal and α-phellandrene were less attractive than hexane. 【Conclusion】 The taxis of H. oblita to U. parvifolia, A. theophrasti and R. communis is not equivalent to its feeding preference.

【Aim】 A large quantities of crop straws produced annually are not effectively used, causing waste of resources. Some crop straws are fermented into animal feed, but they are rarely adapted as feed of insects. This study aims to extend the utilization of crop straw and to reduce the feed cost for breeding Tenebrio molitor. 【Methods】 Different feed formulas made from the conventional feed of T. molitor, fermented corn stalk and fermented sweet potato straw were designed by extreme vertex mixing design method, and the optimal feed formulation was screened by determining the effects of the feed formulation on the growth indexes (biomass increment rate, mortality, body length, feed utilization rate and conversion rate) and physiological indexes (moisture content, ash content, crude fat content, crude protein content, SOD activity, total sugar content, phosphorus content, content of medium and trace elements, and heavy metal content). 【Results】 The results showed that a certain amount of fermented corn stalk and fermented sweet potato straw added in the conventional feed was more beneficial to the growth of T. molitor. In the experimental groups with higher biomass increment rate, T. molitor had higher feed utilization rates and conversion rates. The higher the proportion of sweet potato straw in the formula, the higher the mortality trend of T. molitor. Different feed formulation had no obvious effect on the body length and physiological indexes of T. molitor larvae. The optimal feed formulation for T. molitor was as follows: conventional feed∶fermented corn stalk∶fermented sweet potato straw=37.24∶20.72∶42.04. Compared with the conventional feed formulation, the feed cost of the optimal feed formulation was decreased by 56.94%. The biomass increment rate of T. molitor larvae reared with the optimal feed formulation reached 32.52%, higher than that reared with the conventional feed (25.17%). Moreover, the mortality rate of T. molitor larvae reared with the optimal feed formulation was low and the utilization of crop straw feed was high. 【Conclusion】 Based on a reasonable formulation, the crop straw can be used as the feed of T. molitor, which can not only reduce the feed cost for breeding T. molitor, but also raise the utilization rate of crop straw. So the formulation is of great application prospective.

 【Aim】 The semiectoparasitoid Sclerodermus guani tends to parasitize solitary wood-boring insects in concealed habitat (trunk or seed). Effective mating tactics are critical for population colonization and expansion of S. guani. This study aims to explore the mating behavior of S. guani and to unveil its mating tactics. 【Methods】 The mating process of both male and female adults of S. guani (♀∶♂=1∶1) was recorded with dissecting microscope, video camera and insect behavior tracker in the laboratory, and the differences in behavior performance, time allocation and speed of mating between female and male adults during the whole mating process were compared. 【Results】 The mating process of S. guani adults can be divided into three phases, i.e., pre-copulation, copulation and post-copulation, and the mating behavior shows a series of characteristic procedures including antennal drumming, mounting females, walking on the back of females, probing and copulation. In the pre-copulation phase, males walk around quickly, touch and drum females by antennae, and touch females by mouthpart. After mounting females, males walk on the back of females and still keep tapping females with antennae or touching with mouthpart. Females always keep a stereotypical posture of being stationary with head down. The total lasting time for the pre-copulation phase was about 653.617±54.160 s (mean±SE). During copulation, males insert their aedeagi, their forelegs incline to the front-end of abdomens of females at an angle of 45°, while their mid legs and hind legs hold the abdomens of females, and the mating duration was about 43.567±7.120 s. In the post-copulation phase, males signal the end of copulation by dismounting and moving away from the copulation site while females keep immobile for approximately 172 s. Both male and female adults exhibit multiple mating behaviors in the whole mating process. With the increasing of mating frequency, the mating duration increases at first and then decreases. In the whole mating process, the mating behavior of male and female adults is first decelerated and then accelerated. The mean mating velocities of S. guani in precopulation, copulation and post-copulation were 3.111, 0.595 and 1.016 cm/s for female adults and 2.754, 0.895 and 1.314 cm/s for male adults, respectively. 【Conclusion】 Male adults of S. guani behave actively during the mating process, suggesting that they play leading roles in spouse search, recognition and selection. The results of this study provide the theoretical basis for artificial reproduction, release and population rejuvenation of S. guani in the field.

【Aim】 The melon fly, Bactrocera cucuribitae is an important invasive pest with wide host range, causing serious harm. This study aims to explore its population differentiation and genetic variation in China. 【Methods】 The genetic diversity of a total of 190 individuals collected from 21 regions of 7 provinces in China was analyzed using nine polymorphic microsatellite loci as the molecular markers. 【Results】 For the 21 geographical populations of B. cucuribitae, the average percentage of polymorphic loci was 97.08%, Shannon’s diversity index(I) was 0.8841, and the genetic differentiation coefficient among populations (F_ST) was 0.12806, suggesting that genetic differentiation occurs among the 21 geographical populations. The UPGMA cluster analysis showed that the populations of Hainan (excluding Sansha), Guangdong, Guangxi, Yunnan and Sansha of Hainan were clustered into one clade, while the populations of Fujian, Jiangxi and Sichuan clustered into separate clades, respectively. 【Conclusion】 A certain degree of genetic differentiation has occurred among the melon fly populations in China, but the accumulated variability is limited.

  Bumblebees are one group of the most important commercial pollinators. Domestication and utilization of bumblebee would make up for the decline of natural bee-pollinators and meet the demands of modern agriculture pollination. Nutrition and feed is one of the key issues to realize the domestication and industrial production of bumblebees. In this article, we reviewed how natural pollen, artificial diet with single or mixed pollen gathered by honeybee, feed with different ratios of protein and fat, feed with different amino acid levels, and feed with nutrient elements or royal jelly added affect the bumblebee development. The mixed pollen has promoting functions on larval weight as compared to the single pollen. The optimal ratio of protein to fat ingested by Bombus terrestris is 14∶1. High amino acid level can promote the oviposition of queens and maturity of larvae. Carbohydrates with nutrient elements added can promote the oviposition of queens and foundation of colonies. The royal jelly added in feed can enhance the survival and spawning rate of queens. We proposed that the future research should focus on the feed meeting the nutrient needs of different developmental stages of the local bumblebees and the intestinal symbiotic bacteria which may affect the metabolism and development of bumblebees.