The activity of phenoloxidase (PO) from the hemolymph and cuticle of Tenebrio molitor larvae was investigated at different time (1-7 h) after molting with the microtitration method. The results showed that the hemolymph PO activity slowly decreased within 3 h after the larva molted but increased at 4-7 h after molting. The cuticle PO activity showed no remarkable changes within 1 h after the larva molted, but decreased at 3 h after molting. The PO activity nearly reached the normal level at 6 h after the larva molted. Meanwhile, determined by LineweaverBurk plot the Km value of PO extracted from the hemolymph and cuticle was 1.176 and 0.881 mmol/L, respectively, indicating that PO from the cuticle has a higher affinity to substrate than that from the hemolymph. The results showed that both cuticle and hemolymph PO were involved in cuticle sclerotization of T. molitor, but have differences in action mode and affinity to substrate.

【Objective】 To study the inhibitory effect of cantharadin extracted from meloids Mylabris cichorii on human laryngeal carcinoma HEP-2 cell lines and human gastric carcinoma BGC-823 cell lines, and the influence on cell cycle. 【Methods】 Human laryngeal carcinoma HEP-2 cell lines and human gastric carcinoma BGC-823 cell lines were cultured by cell culture technique. MTT colorimetry was used to evaluate the inhibitory effect of cantharidin on cell grouth. Flow cytometry was used to measure the induction of cell cycle arrest. Microscope was used to observe the morphological changes of the cells. 【Results】 Cantharidin displayed the inhibitory effect on the growth of HEP-2 cells at the concentration of 1.28 μmol/L. The inhibition was in a dose-dependent manner with the IC50 value of 2.88 μmol/L. And cantharidin displayed the inhibitory effect on the growth of BGC-823 cells at the concentration of 20.4 μmol/L. The inhibition was in a dose-dependent manner with the IC50 value of 54.85 μmol/L. After HEP-2 cells were treated with 1.44 and 2.88 μmol/L cantharidin for 24 h, their distributions in G2-M phase and S phase increased from 8.21% to 22.29% and from 14.33% to 21.61%, respectively, while that in G0-G1 phase decreased from 77.45% to 56.10% and no apoptosis was induced. Cell shrinkage, membrane budding, and chromosome lagging of some HEP-2 cells were observed under microscope. 【Conclusions】 The results suggest that cantharidin may have higher application significance to the therapy of laryngeal cancer, as compared with that of gastric cancer. Cantharidin can inhibit the growth of human laryngeal carcinoma HEP-2 cell lines.

Helicoverpa armigera is an important lepidopteran pest of many crops including cotton. Molecular analysis will promote pest control in the future. The gene that encoding triosephosphate isomerase in Helicoverpa armigera, Hatpi, was molecularly cloned and analyzed in this study. The cDNA of Hatpi (GenBank accession no. AY736358) is 1 149 bp in length and encodes a 248 amino acid protein with the estimated molecular mass of 26.4 kD and isoelectric point of 5.82. (βα)8 structure found in the deduced protein structure of HaTPI was similar to that of other triosephosphate isomerase. High identity was also found in the active catalytic sites (Lys12, His94, and Glu165) and peptide motifs (AYEPVWAIGTG and GGASLKPEF). RT-PCR analysis results showed that Hatpi was expressed in the embryo, larva, pupa and adult of H. armigera, suggesting Hatpi may play roles in various developmental stages of H. armigera.

Entomopathogenic nematode is a potential factor for biological control of underground pest. A strain of Heterorhabditis isolated from Cangzhou of Hebei province was identified based on the morphological characters and ITS-rDNA sequence analysis, its virulence to white grubs was also determined in the laboratory. Morphological measurement of infective juveniles and males showed that the population was most closely related to Heterorhabditis bacteriophora, while the results of ITS1-rDNA sequences alignment and phylogenetic analysis indicated that the population had the closest genetic relationship with H. bacteriophora. Based on the morphology and biological characters, the population was identified as H. bacteriophora strain Cangzhou. Pathogenicity tests of the nematode to white grubs (2nd instar larvae of Holotrichia oblita, H. parallela and Anomala corpulenta) showed that the mortality of H. parallela larvae was significantly higher than that of the other two scarabes (P<0.05) after infection of 72 h. After 120 h, the mortality of H. parallela and A. corpulenta larvae were 93.3% and 80.0%, respectively, without significant difference (P>0.05), suggesting that the nematode has strong virulence against them. Virulence tests of different nematodes to larvae of H. parallela indicated that the larvae which were infected by H. bacteriophora strain Cangzhou had higher mortality than those infected by Steinernema feltiae and S. longicaudum after infection of 96 h (P<0.05), suggesting that the virulence of H. bacteriophora strain Cangzhou is significantly higher than the other two nematodes.

The economic importance of the green plant bug, Lygus lucorum Meyer-Dür, has become prominent in area where transgenic Bt cotton are widely planted in China. Controlling of green plant bugs relies mainly on insecticides, and chemical control is one of the important strategies used in IPM. This study was designed to assess acute contact toxicities of conventional and novel insecticides to green plant bugs by two different bioassay methods including glass-vial and topical application. Thirty insecticides, including organochlorines, organophosphates, pyrethroids, carbamates, nereistoxins, neonicotinoids, phenylpyrazoles, antibiotics, insect growth regulators (IGRs), and botanical insecticides were selected to investigate their toxicities against adult green plant bugs. Median lethal concentrations (LC₅₀) of some insecticides were first determined by the two methods. The results showed that in laboratory bioassays, general insecticides including organochlorines, organophosphates, carbamates and pyrethroids were highly toxic to adult green plant bugs. Five (malathion, chlorpyrifos, bifenthrin, methomyl and endosulfan) of eight most toxic insecticides on the bugs among all the test chemicals were general insecticides. Novel insecticides phenylpyrazole showed the highest acute contact toxicity, of which fipronil had the highest toxicity to green plant bugs. The LC50 values of fipronil by two bioassay methods were 0.13 and 0.15 mg·L^-1, respectively. IGRs, antibiotics and botanical insecticides, however, had no obvious acute contact toxicity to adult green plant bugs.

To obtain a comprehensive evaluation of cold hardiness of the red imported fire ant, Solenopsis invicta Buren, the super cooling points (SCPs) of different casts at developmental stages and the ability of workers to survive at low temperature were measured based on materials collected from S. invicta natural populations of Shenzhen, Guangdong in 2005-2006. The results showed that there was a significant difference in SCPs between casts and three developmental stages while the SCPs of the larva, adult and pupa reduced successively. No significant difference was found between the workers and the winged ants in SCPs, but significant difference existed between male and female winged ants. SCPs fluctuated over winter, reduced from October and got to the bottom (-12.68℃) in February, and rose to -9.51℃ in March. The survivorship of workers (S^T) showed a strong relationship with the exposure temperature (T) and the exposure time (t), fitting the Logistic equation. When the exposure time was 0.5 h, the survival rate of workers was 15.3％ at -14℃. At the exposure time of 1, 2 and 4 h, the entire lethal temperatures for S. invicta were -13℃, -9℃ and -9℃, respectively. When the exposure temperature was -10℃, all workers died within 240 min; while at -11℃, it took only 120 min. Fluctuation and persistence of low-temperature were correlative with the survival rate of workers. Under more fluctuating low temperature, the workers had a higher mortality. It took 9 d for the survival rate to drop to 0 under the condition of 4±9℃, while it was longer than 15 d for that under 4±0℃. But the survivors grew stronger in cold tolerance. Compared with the control, treatments under fluctuating temperature of 4±6℃ and 4±9℃ for 4 d could raise the survived workers’ cold tolerance at low temperature significantly. The results suggest that the fire ant can obtain rapid acclimatization when exposed to low temperatures, and it has strong adaptability to extreme weather.

【Aim】 In order to discover the behavior feature of solitary pollinates and provide the basis for developing new resource of bees, the research on the behavior of nesting and food-storing of Xylocopa tranquebarorum (Swederus) was carried out. 【Methods】 The whole nesting process of X. tranquebarorum was observed through visual observation and photographing, and the nest hole size of X. tranquebarorum was measured with vernier caliper. We also observed the single bee bread size and the number of all bee bread brewed throughout its lifespan using nest anatomy in the laboratory. 【Results】 X. tranquabarorum normally nests on the bamboo, occasionally also on the reed. The favorite bamboo species of them were Bambusa multiplex and Phyllostachys spp. with stem diameter about 1.2-2.5 cm. The nesting behavior included six successive phases: (1) the female chose suitable nesting site; (2) the female excavated the bamboo culm to make an entrance of nest; (3) the female cleaned its nest; (4) the female collected pollen and nectar to brew bee bread; (5) the female lay one egg on every bee bread; (6) at last it would construct cell partition to separate the bee bread from the others. Most of nests were located in 1 m away from old nests. The female needed 292（±29） min to finish one entrance of nest. The female spent 17.31(±0.52) min in each pollen and nectar collecting trip and 22 to 40 pollen and nectar collecting trips to finish one bee bread. The female would spend 16.45(±1.08) min to stay in nest and 15.29(±1.03) min to unload the pollen and nectar to finish one of the six pieces of bee bread which it would make throughout its lifespan. The bee bread was near rectangular, 12-18 mm long and 6-10 mm wide, and its weight was about 0.7140(±0.0269) g. 【Conclusions】 The nesting behavior among different female individuals of X. tranquebarorum was similar, while the number of pollen and nectar collecting trips and the period of food-storing among different individuals were significantly different.

In order to study the impact of heavy metals on Pirata subpiraticus, 50 soil samples and 150 individuals of P. subpiraticus were collected from 5 different habitats in Nanyang City, Henan Province in July 2008. The contents of heavy metals (Cd, Pb, Cu and Zn) of soil and P. subpiraticus were measured using atomic absorptions pectrometry. The carapace width, female weight, egg sac weight, the volume and number of eggs were measured and counted. The results showed that the contents of Cd, Cu and Zn in P. subpiraticus in varios habitats were positively correlated with those in soil, and significantly higher in 4 heavy metal polluted habitats (TBJK, TBTK, NYYT, and NYJG) than the control habitat (BTM nature reserve); the result for Pb content was same, but it was significantly higher in TBTK and NYYT than the control habitat (BTM). Principal component analysis (PCA) results suggested that Cd, Cu and Zn could be principal indicators of heavy metal pollution. Females from populations with high concentrations of heavy metals showed a strongly reduced fecundity, indicating a high reduction in resource availability due to detoxification processes. Egg size in contrast was negatively correlated with fecundity and as a consequence positively related with internal metal burden. The conclusion is that changes of P. subpiraticus in the relationship between offspring size and offspring fitness will result in an altered balance between offspring size and P. subpiraticus could be used as a very important bio-indicator for heavy metal pollution.

【Aim】 To study the population genetic variation and the diversity level of Anopheles lesteri from China. 【Methods】 The 139 specimen of 9 populations from China and South Korea were identified by PCR assay. Mitochondrial DNA cytochrome oxidase sununit I gene was amplified, and the mtDNA-COI gene sequences were sequenced and analyzed. 【Results】 In this study, 49 haplotypes were obtained, which were at a high level of homoplasy, and the haplotypes of Yunnan population showed to be the expansion origin. The results of the analysis of molecular variance (AMOVA) showed that the percentage of variation within a population (64.95%) was greater than that among populations (35.05%). The FST value was 0.3504, and the genetic divergence among populations was significant. Mantel test results indicated that the level of gene flow was negatively correlated with geographic distances (R²＝0.1322). The population genetic structure fits the isolation-by-distance model. 【Conclusion】 The greatest difference is found between the populations of South Korea and Liaoning and other populations from China, and they have exhibited obvious differentiation. The level of variation among populations except those of Liaoning and South Korea is low.

Oviposition is the important life phase in insects. Before, during or after egg-laying, most females deposit secretions near eggs. These secretions may serve as egg-adhesive substances or egg-cover substances and protect eggs and early larvae. Some insects also use the secretions as egg marking pheromones which can mediate intra- and inter-specific competition of natural resources. Considering the specific physiological and ecological functions and the influence on population densities, the deposition of secretions associated with oviposition is an evolutionary adaptation. In this article, we reviewed the deposition and physical characteristics of secretions during oviposition in various insects, and the chemical components, possible functions and excretion organs of the sectetions and the microbe species in them were also summarized.

Changes in the levels of haemolymph cations of 5th instar larvae of Pure Mysore, NB₄D₂ and CSR₂ fed on M-5, S-36 and V-1 mulberry varieties were investigated. The larval haemolymph showed low Na⁺ and very high K⁺ and Mg²⁺ concentrations and moderately high Ca²⁺ like the mulberry leaf. The haemolymph cation levels increased significantly during the active feeding period of the larva. A negative correlation existed between the levels of cations in haemolymph and excreta. The haemolymph cation levels were held by controlled excretion of the cations. The rates of elimination of cations were lower during feeding stages than during non feeding stages. The haemolymph cation levels of bivoltine races were about 30% higher than the multivoltine PM. The impact of race was significantly more than that of mulberry variety or ontogeny in upward changes in haemolymph cations.

In order to make clear the relationship between parasitoid hymenopteran insect species and the existence or absence of yolk protein, as well as their immunological relationships, we used SDS-PAGE and Western blot analysis to characterize the yolk protein profiles and determine their immunoreactions with the polyantiserum or monoclonal antibodies against Pteromalus puparum yolk soluble protein in twelve hymenopteran parasitoid species. Combined with what have been achieved for parasitoid yolk proteins, we conclude that the protein profiles of the wasps differ noticeably with respect to the presence of approximately 200 kD vitellogenin in Pteromalidae, Eupelmidae, Ichneumonidae and Aphelinidae, and the absence of this protein in Braconidae, but there exist several peptides with molecular mass of 40-80 kD. Furthermore, there exists a 62 kD protein in all the tested parasitic wasps.

To find some eco-friendly components from plants as mosquitocide, the fumigant activity of essential oil from Zanthoxylum ailanthoides fructification to the adults of Aedes albopictus and Culex pipiens quinquefasciatus was tested, and its insecticidal activity against the larvae and pupae of the two mosquito species was evaluated. The volatile components of this oil were also analyzed by gas chromatography-mass spectrometry. The results showed that at the dosage of 102.145 μg·cm^-3, the KT₅₀ values of this oil for adults of Ae. albopictus and Cx. pipiens quinquefasciatus were 2.788 and 3.505 min, respectively, while the 24 h mortalities of adults of the two mosquito species were 100% and 97.53%, respectively. The 24 h LC₅₀ values of this oil for 4th instar larvae of Ae. albopictus and Cx. pipiens quinquefasciatus were 45.237 and 20.759 mg·L^-1, respectively. Fourteen chemical compounds were identified from the essential oil from Z.ailanthoides fructification, and the main component of this essential oil is 2-undecanone with the peak-area ratio of 89.86%. The results demonstrate that the oil from Z. ailanthoides fructification has strong insecticidal activity against A. albopictus and Cx. pipiens quinquefasciatus, and it has a great potential to be developed as a natural mosquitocide.

To probe the pathogenic mechanism and provide theoretical basis for safety and sustainable utilization of Bt corn, the histopathological changes in the midgut of larvae of the Asian corn borer, Ostrinia furnacalis (Guenée), fed on Bt-transgenic corn expressing Cry1Ab protein were observed by transmission electron microscopy （TEM）. The results showed that the midgut cells and their cell organelles of the O. furnacalis larvae fed on the Bt corn tissues exhibited distinct pathological changes. The midgut cells began to change at 12 h after ingestion of Bt corn. The microvilli of the midgut epithelial cells began to fall off and the endoplasmic reticulum became swollen. After 24 h, the number of endoplasmic reticulum increased and the cavity of goblet cell enlarged. Many microvilli sloughed off and cells became vacuolated after 48 h. Cell vacuolation was more obvious with time going. The pathologic degrees were disparate among cells in the early period of infection. Desquamation of microvilli and swelling of endoplasmic reticulum occurred universally in most midgut cells. In conclusion, the insecticidal protein expressing in transgenic Bt corn can cause pathological changes to midgut cells of O. furnacalis larvae and kill them finally.

A total of 51 species of armored scale insects occurring in 13 different countries were intercepted by Korean quarantine officers on shipments of plants at the ports of entry in the Republic of Korea from 1996 to 2008. A key and photographs to help identify the 51 intercepted species of armored scales insects are provided.

This note reports the occurrence of gynandromorphism in Polistes nimphus (Christ, 1791) in China. External features of the insect are presented. The insect was collected in Mt. Donglingshan, Mentougou, Beijing. The specimen studied is deposited in the Institute of Zoology, Chinese Academy of Sciences.