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甲胺磷(methamidophos)具有内吸、触杀和胃毒杀作用,防治抗性蚜、蟥和水稻叶蝉、悦虱等药效较好,但残留期较长,有时会影响作物的品质。通过对贵阳地区水稻中甲胺磷农药残留分析,得到贵阳地区的大米中甲胺磷未检出。样品以丙酮提取,经过盐析、再经二氯甲烷萃取后进行气相色谱分析(最低检测浓度为0.03μg/g),本方法的结果符合农药残留分析的要求,因此说明贵阳地区的大米中甲胺磷没有超标,为贵阳地区绿色食品的开发提供理论依据。 相似文献
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铜、镉、敌敌畏和甲胺磷对南美白对虾幼虾的急性致毒及相互关系 总被引:15,自引:0,他引:15
在恒温(25±1℃)和充气条件下,研究了铜、镉、敌敌畏和甲胺磷对南美白对虾的急性致毒效用,得到了铜、镉、敌敌畏、甲胺磷对幼虾的24hLC50、48hLC50、72hLC50、96hLC50,四种毒物的安全浓度分别为0.008、0.001、7.6×10-4、7.8×10-4mg/L,四种毒物的毒性大小顺序为甲胺磷>敌敌畏>Cd2+>Cu2+.铜与敌敌畏、甲胺磷对南美白对虾幼虾的联合毒性作用为相加作用,镉与敌敌畏、甲胺磷的联合毒性作用为拮抗作用. 相似文献
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The effect of tri-o-cresyl phosphate (TOCP) and methamidophos (MET) on potassium-stimulated 45Ca uptake by brain synaptosomes in hens was studied. An in vivo test showed that TOCP increased potassium-stimulated calcium uptake 2 h after its administration, but that verapamil suppressed the enhancement of this calcium uptake. An in vitro test showed that lower concentrations of TOCP stimulated calcium uptake by synaptosomes, but that higher concentrations inhibited the uptake. In contrast, all tested concentrations of MET obviously inhibited calcium uptake; however, since calcium uptake was decreased by the administration of verapamil plus either TOCP or MET, the mechanism by which TOCP affects the voltage-operated calcium channel may be different from that of MET. The disruption of calcium homeostasis may be involved in organophosphate-induced delayed neurotoxicity (OPIDN). Calcium channel blocker may ameliorate OPIDN by maintaining calcium homeostasis in nerve cells. 相似文献
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In view of the ubiquitous co-existence of methamidophos, acetochlor and copper (Cu) in agricultural soils, ecological detoxification of methamidophos in phaiozem by earthworms was examined using the detoxic incubation experiments with illumination. It was validated that the earthworm Eisenia fetida is a useful soil animal in the process of methamidophos detoxification as the assistance of soil microbes and enzymes. Due to the action of earthworms, the half life of methamidophos with concentration of 15 mg/kg in phaiozem could decrease from 5.61 days to 5.08 days. Dynamics of methamidophos detoxification by earthworms could conform to the logistic model. Under the condition of multiple pollution combined with acetochlor (20 mg/kg) and Cu (300 mg/kg), ecological detoxification of methamidophos by earthworms became complicated. Acetochlor played a promoting role in the biodegradation of methamidophos to some extent, while it was basically inhibited by Cu. 相似文献
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为研究乙酰甲胺磷在蔬菜上使用后产生的农药残留风险,以不同制剂、不同浓度的乙酰甲胺磷为试验材料,分析乙酰甲胺磷及其代谢产物在小白菜中的消解动态变化,结果表明:(1)乙酰甲胺磷代谢产生甲胺磷,代谢率与农药的剂型有关;(2)不同制剂的乙酰甲胺磷在小白菜中的半衰期基本一致,在26.8~28.5 h之间,而代谢物甲胺磷的半衰期略有差异,在36.7~42.3 h之间;(3)乙酰甲胺磷在叶菜中使用会产生较高的甲胺磷残留风险,且安全间隔期在12天以上。 相似文献
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两种蔬菜中甲胺磷、氧乐果和克百威的残留量分析 总被引:5,自引:0,他引:5
分别选取一种瓜菜 (黄瓜 )和一种叶菜 (生菜 ) ,选择了两种有机磷 (甲胺磷、氧乐果 )和一种氨基甲酸酯类 (克百威 )农药 ,对这 3种农药在两种蔬菜中的残留测定方法进行了研究。采用弗罗里硅土柱提取的方法进行前处理 ,淋洗液浓缩后用 GC- NPD测定 ,建立了一种简便快速的检测方法 ,并采用该方法对实际处理样本进行了测定。从方法添加回收率和实测数据可以看出 ,该方法净化提取效果好 ,结果平行性好 ,灵敏度较高 ,是一次快速准确测定蔬菜中农药残留的成功尝试。 相似文献
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The susceptibilities to methamidophos as well as the kinetic and inhibitory parameter of acetylcholinesterases (AChE) and the activities of carboxyestsrases (CarE) and glutathione-S-transferases (GST) were studied in 18 species field populations of insects collected in Fuzhou, China during April and May 2000 and 2001. The insect species included five hymenopteran endoparasitoids, one hymenopteran exoparasitoid, one hymenopteran hyperparasitoid, one dipteran predator, four coleopteran predator ladybirds, six herbivorous pest insects of lepidoptera, diptera, homoptera, and coleoptera, respectively. There existed significant correlations between the susceptibility to methamidophos and the ki values of AChE to methamidophos, dichlorvos, and carbofuran and between the ki and Vmax values of AChE among 18 species of insects. The six herbivorous pests and four ladybirds showed significantly low ki and Vmax values of AChE compared to the seven parasitoids and predator Epistrophe balteate. It was difficult to correlate the susceptibility to methamidophos or the ki values with the Km values of AChE, or with the activity of CarE and GST. The activities of CarE and GST varied depending on the different insect species. Significant synergisms of piperonyl butoxide (PB), triphenyl phosphate (TPP), and diethyl maleate (DEM) with methamidophos were observed in 14 pest insects and their natural enemies. Synergisms of PB were found to be the greatest. Reduced ki values suggested that insensitive AChE might play a critical role in the tolerance to methamidophos in the 18 insect species. The detoxification enzymes, mixed-function oxidase (MFO), CarE, and GST, were believed to be involved in the tolerance to methamidophos. MFO might play the most important role, and CarE or GST might be important in the tolerance in some insect species. Different models of tolerance to methamidophos and enzymatic potential were existed in parasitoids, predators, and herbivores based on the different selection of insecticide pressure (either directly by exposing to the spray in the field, or indirectly by the insecticides penetrated into the body of host insects) as well as different ecological and biological habitats. 相似文献
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本文研究了甲胺磷在水稻田中的流失情况。试验结果表明:在水稻田中甲胺磷的径流和渗漏流失总量约占施入量的12%;渗漏流失甲胺磷大于氰戊菊酯。建议稻田中少用甲胺磷高毒农药,以减少对地下水的污染。 相似文献