Publications by authors named "Wei-Bin Ma"

Four typical estuaries located in the Ruxi River, a tributary of the Yangtze River, were selected to investigate the possibility of mercury pollution in tributary estuaries from the Three Gorges reservoir water storage. Water samples were collected during the water storage period (September to October), the flooding period (November to December), the water withdrawal period (February to March), and the drying period (May to June) to determine the levels of mercury species including total mercury (THg), particulate mercury (PHg), dissolved mercury (DHg), reactive mercury (RHg), total methylmercury (TMeHg) and dissolved methylmercury (DMeHg). The results showed that the concentration of THg and TMeHg in the estuary of the Ruxi River was comparable with that of other reservoirs or natural waters in China.

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We studied the knockdown activity and lethal toxicity of 6 essential oil compounds-methyl salicylate, linalool, 2-phenethyl alcohol, eugenol, β-citronellol, and trans-cinnamaldehyde-as fumigants against adult female Culex pipiens pallens in the laboratory. Of the 6 products tested, trans-cinnamaldehyde was the most toxic (LC50  =  0.26 µl/l air, 24 h) with a slow knockdown time (KT95  =  176.

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To seek natural products for the development of environment friendly mosquito control agents, fumigant activity of eleven essential oil compounds and the joint action of the active compounds were evaluated against Culex pipiens pallens adults. Fumigant bioassay demonstrated that carvacrol exhibited the highest fumigant activity followed by thymol and l-perillaldehyde, with LC50 values of 0.26, 0.

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The Magnaporthe oryzae genome contains two homologous CYP51 genes, MoCYP51A and MoCYP51B, that putatively encode sterol 14α-demethylase enzymes. Targeted gene deletion mutants of MoCYP51A were morphologically indistinguishable from the isogenic wild type M. oryzae strain Guy11 in vegetative culture, but were impaired in both conidiation and virulence.

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An insertional mutagenesis screen was used to investigate the biology of plant infection by the devastating rice blast pathogen, Magnaporthe oryzae. Here, we report the identification of a new mutant, LY-130, which is defective in multiple steps during infection-related morphogenesis and pathogenicity. Analysis of the mutation confirmed an insertion into gene MoRIC8, which encodes a 480-amino-acid protein that is a putative homologue of the Ric8 regulator of GTP-binding protein (G-protein) signaling, previously described in animals.

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