Cytochrome P450 plays a dominant role in the metabolism of a wide variety of both endogenous and xenobiotic substances. The evolution of P450 gene function was analyzed in the genome of the pea aphid, Acyrthosiphon pisum, using the mRNA and amino acid data. A genome-wide analysis of P450 genes was performed in pea aphid genome by bioinformatical methods. The results showed that sixty-nine P450 genes were discovered in pea aphid genome, which are of a typical superfamily and belong to 13 families and 18 subfamilies. We collected expression sequence tag (EST) evidence for 39 putative P450s genes, which are expressed at the transcriptional level and more likely to be true P450s. Because of significant differences in gene sequences, among 69 P450 genes 18 genes could not partitioned into any group, while the rest 51 P450 genes were partitioned into 10 groups by a criterion that the genes belong to a group when their amino acid identity is more than 60%. Positive selection and gene conversion were analyzed in 8 groups (including 47 genes). Positive selection was detected in only one group (including 9 genes). The positively selected sites with a more than 95% probability were 20T and 27N, located in substrate recognition site (SRS1) and D-helix, respectively. The significant gene conversion events were detected in 3 groups (8 sequences). P450 genes that identified gene conversion events were members of CYP4 family, which were CYP4C, CYP4G and CYP4V subfamily, respectively. Protein similarity between P450 genes with gene conversion was 70%-95%. P450 genes with gene conversion lay in the same scaffold, e.g., M_001944991 and XM_001951794 lay in SCAFFOLD12542, while XM_001945510 and XM_001944057 lay in SCAFFOLD7010. The results suggest that P450 genes may gain new function through gene duplication and gene conversion. Moreover, twenty motifs were identified, of which 5 motifs existed in over 90% of P450 genes.

In order to reveal the insecticidal activity and mechanism of cantharidin, the effect of cantharidin on activities of carboxyl esterase (CarE), phosphatases, glutathione S-transferase (GST), O-demethylase of cytochrome P450 and PPO in larvae of  Mythimna separata (Walker) were assayed. The results showed that CarE in the treated insects was distinctly activated and at 48 h after treatment their specific activity was 1.68 times that of the control. ACP activity showed no distinct change at 6 h and 12 h after treatment, but was activated at 24 h after treatment and significantly different from the control (P＜0.05). The activity of alkaline phosphatase (ALP) was inhibited obviously, and the inhibition became more intensive as the exposure time prolonged. The activity of O-demethylase was first inhibited, and then activated. GST activity was first activated, and then inhibited. PPO activity was strongly inhibited by cantharidin both in vitro and in vivo. It is so inferred that catharidin can affect the metabolic enzymes distinctly, and the inhibition on ALP and PPO may be related to its toxic effect.

 In order to investigate the host-feeding behavior of Diglyphus isaea (Walker), the oviposition behavior and the trade-off between the two behaviors in different nutritional status, we compared the influences of the parasitism, host-feeding and the lethal capability of female D. isaea on Liriomyza sativae Blanchard larvae that were supplied with the distilled water (hungry), diet with honey and that without honey, respectively. The results showed that under the condition of no-choice, parasitoids in the three kinds of nutritional status had higher parasitism rate on the late instar larva, higher feeding rate on the mid-instar larva, and the mortality and the lethal capability had significant difference. Parasitoids in the three kinds of nutritional status had no lethal capability to the early instar larva. Under the condition of choice, the hungry parasitoids had the lowest parasitism rate (5.0%±1.6%) and the highest feeding rate (16.0%±2.9%), especially the feeding rate of the late instar larvae amounted to 91.9% of all instar larvae. When honey were supplied, the feeding rate (8.3%±0.9%) and the mortality (17.7%±1.1%) of the parasitoid was the lowest; however, its parasitism rate (13.3%±1.1%) and the mortality (28.4%±1.8%) were the highest when no honey was supplied. In conclusion, the parasitoids feeding hosts have stronger lethal capability than those feeding honey, and the parasitoids supplied with host food have stronger activity than those not supplied with host food.

This study aims to provide general technicians who manage pests in production with a convenient way to recognize insects. A simple and viable scheme to identify insect voiceprints automatically is introduced using a sound parameterization technique that dominates speaker recognition technology. The acoustic signal was preprocessed and segmented into a series of sound samples.  Mel-frequency cepstrum coefficient (MFCC) was extracted from the sound sample, and a feature model was trained using Linde-Buzo-Gray algorithm to generate vector quantization (VQ) codebook from above MFCC. The matching for a test sample was completed by finding the nearest neighbour in all the VQ codebooks. The method was tested in a database with acoustic samples of 70 different insect sounds. The recognition rate above 96% was obtained, and an ideal time performance was also achieved. The test results proved the efficiency of the proposed method.

In the present paper, Blattella Caudell is reviewed and nine species of Blattella are taxonomically studied from China, including one new species, B. singularis sp. nov., which is described and illustrated. A key to species from China is provided.

Rice stripe virus (RSV) is mainly transmitted by insect vector Laodelphax striatellus in circulative-propagative and transovarial manners. The interaction between RSV and L. striatellus is largely unknown. To investigate the effects of RSV on gene expression in L. striatellus, viruliferous and virus-free L. striatellus populations were detected to reveal the differentially expressed genes with five random primers and three anchor primers by differential display RT-PCR (DDRTPCR). Furthermore, positive-cross test was performed to find optimal conditions of DDRT-PCR by analyzing six critical parameters including cDNA template, random primer, anchor primer, dNTPs, Mg²⁺ and Taq. The results showed that the optimal conditions of DDRT-PCR (25 μL) included cDNA template 3.0 μg, random primer 2.0 μmol/L, anchor primer 2.5 μmol/L, dNTPs 200 μmol/L, Mg2+ 2.0 μmol/L, and Taq 2.0 U. Thirty-five differentially expressed cDNA fragments were isolated by DDRT-PCR. Six of them were verified by RNA dot blot hybridization, and four positive cDNA fragments were obtained. Three positive cDNA fragments were from viruliferous L. striatellus population and shared high homology with 5-hydroxytryptamine receptor 1D gene, gyrase B gene and 60S ribosomal protein L40 gene, respectively. The positive cDNA fragment from virusfree L. striatellus population had no similarity with sequences in NCBI nucleotide databases. The optimal DDRT-PCR system and the differentially expressed cDNA fragments obtained might provide a basis for further study on interaction between RSV and L. striatellus.

 To establish a rapid and effective quarantine method of the honeybee sacbrood virus disease, we developed a real-time RT-PCR assay for detection of bee sacbrood disease using TaqMan probes. A pair of specific primers and a probe used in this assay were designed based on a highly conserved region in sacbrood bee virus. The assay was shown to be sensitive, detecting less than 1.0×10² copies/μL, and specific for the detection of sacbrood bee virus. Cross-reaction with acute bee paralysis virus, deformed wing virus and black queen cell virus was not observed. The coefficient of variation in the stability experiments was 1.6%. A reliable diagnostic result can be obtained just within 4 h. The assay proved to be a rapid, sensitive, specific and repetitive method for rapid detection of sacbrood bee virus from honeybee and honeybee products in quarantine.

To research the influence of temperature on the development and reproduction of experimental populations of the Colorado potato beetle, Leptinotarsa decemlineata (Say), and then provide some basic data for the control and prediction of pest, the development and reproduction of every stage of Leptinotarsa decemlineata (Say) were observed at five temperatures (15℃, 19℃, 23℃, 27℃ and 31℃) in the laboratory. The developmental threshold temperature and effective accumulated temperature of different stages of the Colorado potato beetle were calculated. The results showed that the developmental rate of the Colorado potato beetle increased with the rise of temperature from 15℃ to 31℃. The generation survival rate of the Colorado potato beetle decreased in the order of 27℃＞23℃＞19℃＞31℃＞15℃, suggesting that excessively high or low temperature was unfavorable to the survival. The developmental threshold temperatures required for egg stage, 1st instar, 2nd instar, 3rd instar, 4th instar, whole larval stage, pupal stage and egg-adult period were 9.14, 10.50, 8.17, 10.28, 9.04, 9.59, 10.23 and 10.90℃, while the effective accumulated temperatures were 73.26, 43.22, 39.23, 34.05, 161.97, 273.02, 100.38 and 542.58 degree-days, respectively. It is so concluded that the influence of temperature on the developmental duration, survival rate and reproduction of experimental populations of the Colorado potato beetle was remarkable.

The aim of the investigation was to determine length-weight relationships (LWR) as an alternative method for determining insect biomass. The LWR were calculated for seven aquatic beetles species caught at Choghakhor Marsh in Iran. Individuals’ samples were dried at 60℃ for 24 h, cooled in a desecrator, and weighted to the nearest 0.001 g. Each beetle was also measured for body length to the nearest 0.1 mm. The parameters of LWR (a and b values) were estimated by linear regression on the transformed equation: Log W=log a + b log L. The results indicated that the parameter b on LWR varied between 2.315 and 3.117. Significant LWR with high correlation coefficient (r²) were found for all species examined. The obtained relations can be used in the determination of the weight of the beetle and they are also useful in addressing many ecological questions. The application of the LWR presented here should be restricted to the observed length ranges.

In this paper, the external morphology of the antennal sensilla of female and male Lysiphlebus fabarum (Marshall) is described using scanning electron microscopy. Seven morphological sensillar types were recognized in both sexes. They are sensilla trichodea (ST), sensilla chaetica typeⅠ (SChⅠ), sensilla chaetica typeⅡ (SChⅡ), sensilla basiconica (SB), sensilla coeloconica typeⅠ (SCⅠ), sensilla coeloconica typeⅡ (SCⅡ) and elongated sensilla placodea (SP). The number of sensilla trichodea (ST) is the largest in all sensilla. Sensilla coeloconica typeⅡ (SCⅡ) is only found in female and its number is the least. The shape and structure of most antennal sensilla between male and female adults were not basically different.