The rice water weevil (RWW) Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae) is an invasive insect pest of rice Oryza sativa L. in China. Little is known about the interactions of this weevil with indigenous herbivores. In the present study, adult feeding and population density of the weevil, injury level of striped stem borer Chilo suppressalis (Walker) (Lepidoptera: Pyralidae) and pink stem borer Sesamia inferens (Walker) (Lepidoptera: Noctuidae) to rice, as well as growth status of their host plants were surveyed in a rice field located in Southeastern Zhejiang, China, in 2004 with the objective to discover interspecific interactions on the rice. At tillering stage, both adult feeding of the weevil and injury of the stem borers tended to occur on larger tillers (bearing 5 leaves) compared with small tillers (bearing 2~4 leaves), but the insects showed no evident competition with each other. At booting stage, the stem borers caused more withering/dead hearts and the weevil reached a higher density on the plants which had more productive tillers and larger root system; the number of weevils per tiller correlated negatively with the percentage of withering/dead hearts of plants in a hill. These observations indicate that interspecific interactions exist between the rice water weevil and the rice stem borers with negative relations occurring at booting or earlier developmental stages of rice.
Animals ; Coleoptera ; growth & development ; Oryza ; growth & development ; parasitology ; Population Density ; Weevils ; growth & development

OBJECTIVE: To explore the growing development and community succession of main sarcosaphagous insects on pig carcasses in summer indoor and outdoor environment in Shenzhen area and to estimate the postmortem interval (PMI). METHODS: From early May to August in 2013, in Forensic Medical Examination Center of Shenzhen Public Security Bureau, the main insect species and the decomposition process were observed in two adult pig carcasses of simulative indoor and outdoor environment. The different decomposition stages and the community succession of insects were recorded. RESULTS: The indoor and outdoor pig carcasses showed skeleton 412.5 and 325 hours after death, respectively. The main species of flies on pig carcasses were Chrysomya megacephala, Chrysomya rufifacies and Chrysomya chani. The main species of beetles were Crecphilus maxillosus, Necrobia ruficollis, Saprinus splendens and Dermestes maculatu. The dominant species of flies in the outdoor pig carcasses obviously produced the second generations due to the effect of mass rainfall, nor in the indoor pig carcasses. CONCLUSION There are regular patterns on the community succession of insects on pig carcasses in summer indoor and outdoor environment in Shenzhen area. The activity patterns of seven typical insects and their larva show important value for estimating PMI.
Animals ; Autopsy ; Cadaver ; China ; Coleoptera ; Death ; Diptera ; Environment ; Insecta/growth & development* ; Larva ; Population Dynamics ; Postmortem Changes ; Seasons ; Swine

Sarcophagus beetles, which can not be replaced by Diptera, play a pivotal role not only in estimating PMI of dry human skeletal remains in the later stages decomposition of carcasses, but also the corruption, destruction, decomposition and posture changes of carcasses. This article explicates the succession of sarcophagus beetles on carrion and its influencing factors, and introduces the application and prospects of sarcophagus beetles in forensic entomology. Although few researches focus on sarcophagus beetles at present, it is believed that more and more forensic scientists will pay attention to sarcophagus beetles' application in forensic identification.
Animals ; Coleoptera/growth & development* ; Entomology/methods* ; Feeding Behavior ; Forensic Medicine/methods* ; Humans ; Larva/growth & development* ; Life Cycle Stages ; Postmortem Changes ; Temperature ; Time Factors

OBJECTIVEThe aim of the present study was to screen the Metarhizium strains with high virulence against the larvae of Dorysthenes hydropicus, a serious pest of Citrus grandis.

METHODThirty six strains of Metarhiziums were isolated from the soil of C. grandis GAP base and collected from other institutions, and the pathogenicity of these strains against 1st instar larvae of D. hydropicus was detected at concentration of 1 x 10(8) conidia/g. The high violence strains against D. hydropicus were cultivated in sabouraud dextrose yeast medium at first, then transfer to rice grain. And the sporulations of these violent strains against D. hydropicus were detected.

RESULTTwenty-eight strains showed virulence against D. hydropicus by preliminary study, and 7 strains of them were collected for further study, 6 of the 7 showed high virulence, the highest cadaver rate was higher than 74%. The conidia production of strain 1 and strain 4 were 2.35 +/- 0. 25 (1 x 10(9) conidia/g), 2.21 +/- 0.27 (1 x 10(9) conidia/g), respectively, showed significantly higher than other strains.

CONCLUSIONStrain 1 and strain 4 of the 36 Metarhiziums strains showed high virulence against D. hydropicus, and the highest sporulation ability, so they have a best application prospect.

Animals ; Citrus ; parasitology ; Coleoptera ; microbiology ; Metarhizium ; growth & development ; isolation & purification ; pathogenicity ; Pest Control, Biological ; Plant Diseases ; parasitology ; prevention & control ; Soil Microbiology ; Spores, Fungal ; growth & development ; isolation & purification ; pathogenicity ; Virulence

A quantitative structure-property relationship (QSPR) model in terms of amino acid composition and the activity of Bacillus thuringiensis insecticidal crystal proteins was established. Support vector machine (SVM) is a novel general machine-learning tool based on the structural risk minimization principle that exhibits good generalization when fault samples are few; it is especially suitable for classification, forecasting, and estimation in cases where small amounts of samples are involved such as fault diagnosis; however, some parameters of SVM are selected based on the experience of the operator, which has led to decreased efficiency of SVM in practical application. The uniform design (UD) method was applied to optimize the running parameters of SVM. It was found that the average accuracy rate approached 73% when the penalty factor was 0.01, the epsilon 0.2, the gamma 0.05, and the range 0.5. The results indicated that UD might be used an effective method to optimize the parameters of SVM and SVM and could be used as an alternative powerful modeling tool for QSPR studies of the activity of Bacillus thuringiensis (Bt) insecticidal crystal proteins. Therefore, a novel method for predicting the insecticidal activity of Bt insecticidal crystal proteins was proposed by the authors of this study.
Algorithms ; Amino Acids ; genetics ; Animals ; Artificial Intelligence ; Bacterial Proteins ; classification ; genetics ; toxicity ; Cell Survival ; drug effects ; Coleoptera ; growth & development ; Diptera ; growth & development ; Endotoxins ; classification ; genetics ; toxicity ; Hemolysin Proteins ; classification ; genetics ; toxicity ; Insect Control ; methods ; statistics & numerical data ; Insecticides ; toxicity ; Lepidoptera ; growth & development ; Models, Biological ; Reproducibility of Results ; Toxicity Tests ; methods ; statistics & numerical data