We investigated the reduction of lepidocrocite(γ-FeOOH) by Shewanella oneidensis MR-1 in the presence and absence of Cd. The results showed that Cd^(2+) retarded microbial reduction of γ-Fe OOH and avoided formation...We investigated the reduction of lepidocrocite(γ-FeOOH) by Shewanella oneidensis MR-1 in the presence and absence of Cd. The results showed that Cd^(2+) retarded microbial reduction of γ-Fe OOH and avoided formation of magnetite. The inhibitory effect on γ-Fe OOH transformation may not result from Cd^(2+) toxicity to the bacterium; it rather was probably due to competitive adsorption between Cd^(2+) and Fe^(2+) on γ-Fe OOH as its surface reduction catalyzed by adsorbed Fe^(2+) was eliminated by adsorption of Cd^(2+).展开更多
Field doses of six selected insecticides were tested against the immature(pupae) and mature (adult) stages of Diadegma semiclausum (Hellen) and Oomyzus sokolowskii(Kurdjumov), parasitoids of the diamondback moth, Plut...Field doses of six selected insecticides were tested against the immature(pupae) and mature (adult) stages of Diadegma semiclausum (Hellen) and Oomyzus sokolowskii(Kurdjumov), parasitoids of the diamondback moth, Plutella xylostella (L.). Effects of contacttoxicity (direct spraying) of the six insecticides on emergence of parasitoids were found negligibleon both species except permethrin which caused 37.5% mortality. All adults of both parasitoidspecies died 24 hours after exposure to chlorfenapyr, emamectin benzoate and permethrin. Incontrast, the three insect growth regulators (IGRs), chlorfluazuron, flufenoxuron and teflubenzuron,were found harmless to both species, and adult mortality of both parasitoid species was 0—16.7%.However, parasitism by the females of both parasitoid species was severely impaired when the femaleswere offered the three IGR diluted solutions for 24 hours. Effects of oral toxicities of the IGRson longevity of both parasitoids after 12 hours exposure were found to be significantly differentbetween males and females. Compatibility of tested insecticides with D. semiclausum and O.sokolowskii and integration of compatible insecticides with these parasitoids in integrated pestmanagement programs of crucifers are discussed.展开更多
Cadmium(Cd) contamination has posed an increasing challenge to environmental quality and food security. In recent years,phytoremediation has been particularly scrutinized because it is cost-effective and environmental...Cadmium(Cd) contamination has posed an increasing challenge to environmental quality and food security. In recent years,phytoremediation has been particularly scrutinized because it is cost-effective and environmentally friendly, especially the use of metal-hyperaccumulating plants to extract or mine heavy metals from polluted soils. Under Cd stress, responses of hyperaccumulator and non-hyperaccumulator plants differ in morphological responses and physiological processes such as photosynthesis and respiration,uptake, transport, and assimilation of minerals and nitrogen, and water uptake and transport, which contribute to their ability to accumulate and detoxify Cd. This review aims to provide a brief overview of the recent progresses in the differential responses of hyperaccumulator and non-accumulator plants to Cd toxicity in terms of growth and physiological processes. Such information might be useful in developing phytoremediation technology for contaminated soils.展开更多
基金financially supported by the National Natural Science Foundation of China(41601239)the Highlevel Leading Talent Introduction Program of GDAS,the China Postdoctoral Science Foundation(2016M600644)the"Pearl River Talents"Postdoctoral Program of Guangdong Province,and the National Key Research and Development Program of China(2016YFD0800703)
文摘We investigated the reduction of lepidocrocite(γ-FeOOH) by Shewanella oneidensis MR-1 in the presence and absence of Cd. The results showed that Cd^(2+) retarded microbial reduction of γ-Fe OOH and avoided formation of magnetite. The inhibitory effect on γ-Fe OOH transformation may not result from Cd^(2+) toxicity to the bacterium; it rather was probably due to competitive adsorption between Cd^(2+) and Fe^(2+) on γ-Fe OOH as its surface reduction catalyzed by adsorbed Fe^(2+) was eliminated by adsorption of Cd^(2+).
文摘Field doses of six selected insecticides were tested against the immature(pupae) and mature (adult) stages of Diadegma semiclausum (Hellen) and Oomyzus sokolowskii(Kurdjumov), parasitoids of the diamondback moth, Plutella xylostella (L.). Effects of contacttoxicity (direct spraying) of the six insecticides on emergence of parasitoids were found negligibleon both species except permethrin which caused 37.5% mortality. All adults of both parasitoidspecies died 24 hours after exposure to chlorfenapyr, emamectin benzoate and permethrin. Incontrast, the three insect growth regulators (IGRs), chlorfluazuron, flufenoxuron and teflubenzuron,were found harmless to both species, and adult mortality of both parasitoid species was 0—16.7%.However, parasitism by the females of both parasitoid species was severely impaired when the femaleswere offered the three IGR diluted solutions for 24 hours. Effects of oral toxicities of the IGRson longevity of both parasitoids after 12 hours exposure were found to be significantly differentbetween males and females. Compatibility of tested insecticides with D. semiclausum and O.sokolowskii and integration of compatible insecticides with these parasitoids in integrated pestmanagement programs of crucifers are discussed.
基金supported by the National Natural Science Foundation of China (No. 41501521)a scholarship from the University of Florida, USA
文摘Cadmium(Cd) contamination has posed an increasing challenge to environmental quality and food security. In recent years,phytoremediation has been particularly scrutinized because it is cost-effective and environmentally friendly, especially the use of metal-hyperaccumulating plants to extract or mine heavy metals from polluted soils. Under Cd stress, responses of hyperaccumulator and non-hyperaccumulator plants differ in morphological responses and physiological processes such as photosynthesis and respiration,uptake, transport, and assimilation of minerals and nitrogen, and water uptake and transport, which contribute to their ability to accumulate and detoxify Cd. This review aims to provide a brief overview of the recent progresses in the differential responses of hyperaccumulator and non-accumulator plants to Cd toxicity in terms of growth and physiological processes. Such information might be useful in developing phytoremediation technology for contaminated soils.
