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水稻不同品种或组合对甲磺隆耐药性差异的机制研究 总被引:2,自引:2,他引:2
以水稻乙酰乳酸合成酶(ALS)比活力为研究对象,通过在离体和活体条件下比较其对甲磺隆的敏感性水平,探讨了水稻不同品种或组合的耐药性差异机制。结果表明,离体条件下不同水稻品种或组合ALS对甲磺隆均较敏感,当甲磺隆浓度为100 μg/L时,对ALS比活力抑制率达60%以上,且活力百分比与甲磺隆浓度对数成直线负相关关系,相关程度显著或极显著;活体条件下ALS活力均受到甲磺隆不同程度的抑制,但同一品种ALS活力不随甲磺隆浓度的变化而呈现规律性变化。在甲磺隆浓度相同时,活体条件下所有供试水稻品种ALS活力均显著高于离体条件下的ALS活力,影响程度与植株耐药性差异基本一致,说明甲磺隆在水稻体内存在较强代谢失活作用,代谢失活差异是水稻不同品种或组合对甲磺隆的耐药性差异机制。 相似文献
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苯磺隆·甲磺隆·氯磺隆混合物的液相色谱分析 总被引:2,自引:0,他引:2
本文以甲醇 水 冰乙酸为流动相,采用C18不锈钢柱,检测波长240nm,对苯磺隆、甲磺隆、氯磺隆混合物进行反相高效液相色谱定量分析。该方法的标准差别分别为0.081、0.013和0.013,变异系数为0.886%、0.268%和0.256%,回收率为99.39%、99.29%和99.28%,线性相关系数为苯磺隆r=0.9994、甲磺隆r=0.9992、氯磺隆r=0.9991,线性方程为苯磺隆y=1360088.17x 1389384、甲磺隆y=972186.69X-21262.8、氯磺隆y=789773.50X 86258.8。 相似文献
4.
Cytochrome P450 monoxygenase converts arachionic acid to four epoxyeicosatrienoic acid regiosomes: 5, 6-EET (epoxyeicosatrienoic acid); 8, 9-EET; 11, 12-EET and 14, 15-EET. Recent studies show that EETs are involved in signal transduction. EETs open Ca2+-sensit ive K+ channel and inhibit Na+ channel, Ca2+-sensitive Cl- channel and so on. What is more, EETs have been demonstrated to activate PP60c-src and initiate a tyrosine kinase cascade that mediates mitogenic effects. 相似文献
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通过取代苯氧异丁酸与12-(羟基亚氨基)十五内酯的反应,合成了取代苯氧异丁酰氧亚氨基十五内酯,并测定了其对苋菜的除草活性。所有化合物均经过1H NMR、13C NMR和元素分析确证。初步的生物活性测定结果表明,目标化合物 Ⅲa~Ⅲd 的EC50值分别为34.570、46.492、55.385、50.114 mg/L,其活性比对照药剂2,4-D(117.325 mg/L)高,而比苯磺隆(22.381 mg/L)低。 相似文献
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采用 4 0英尺集装箱熏蒸处理纸箱 ,实验对箱中溴甲烷气体分布及散气后溴甲烷残留进行了检测研究。结果表明 ,温度高低、集装箱中纸箱堆放和电扇鼓风等情况对溴甲烷分布与扩散影响明显。集装箱装满纸箱情况下 ,当温度≥ 2 1℃ ,投药 2h后上、下检测点平均溴甲烷浓度达到最低浓度要求 ;当温度 <2 1℃时 ,投药 2 4h后上检测点平均溴甲烷浓度仍达不到最低浓度要求。当集装箱中间留有通道或使用电扇鼓风情况下 ,投药 2h后各检测点溴甲烷浓度分布达到最低浓度要求。集装箱装满纸箱情况下 ,溴甲烷向大气扩散较慢 ,即使电扇鼓风散气2h ,2 4h后溴甲烷残留量仍达不到安全指标要求。集装箱中间留有通道情况下 ,箱中溴甲烷残留量下降很快 ,并可达到安全指标要求。 相似文献
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MIKI AIDA KAZUYUKI ITOH HIROAKI IKEDA NAOKUNI HARADA YASUO ISHII KENJI USUI 《Weed Biology and Management》2004,4(3):127-135
Paddy herbicides have the potential to cause adverse effects on non-target plants. Susceptibilities of some aquatic ferns ( Azolla japonica Franch. et Savat., Isoetes japonica A. Braun, Marsilea quadrifolia L. and Salvinia natans All.) and duckweeds ( Lemna minor L. and Spirodela polyrhiza Schleid.) to paddy herbicide bensulfuron methyl (BSM) were evaluated with a 20 day exposure experiment using 200 cm2 pots. The BSM concentrations in the surface water of monitoring pots with no plants dissipated exponentially with half lives of 3.5 and 3.9 days at application rates of 15 and 150 g ha−1 , respectively. The BSM concentrations in the surface water 1 day after application in the culture pots were comparable among plant species, and were lower than those in the monitoring pots. Bensulfuron methyl reduced the plant growth in all species. I . japonica showed the lowest intrinsic relative growth rate (RGR) and the lowest susceptibility with an effective dose resulting in 50% growth inhibition (ED50 ) of 21 g ha−1 . Except for I . japonica , the RGR of the duckweeds was similar to the ferns, and ED50 for the duckweeds was higher than the ferns. ED50 for Sa . natans , A . japonica and M . quadrifolia were 1.1, 1.8 and 1.2 g ha−1 , respectively, which were smaller than 1/20 of the recommended field dose (51–75 g ha−1 ) and ranged from 1/2 to 1/6 of ED50 for L . minor and Sp . polyrhiza (6.5 and 3.2 g ha−1 , respectively). These results suggest that BSM application in paddy fields and its runoff in some localities is expected to have adverse effects on the growth of Sa . natans , A . japonica and M . quadrifolia . 相似文献
9.
Methyl donors dietary supplementation to gestating sows diet improves the growth rate of offspring and is associating with changes in expression and DNA methylation of insulin‐like growth factor‐1 gene 下载免费PDF全文
Yang Zhao Yuedong Xuan Daolin Mou Hong Liu Pan Zhou Zhengfeng Fang Lianqiang Che Shengyu Xu Bin Feng Jian Li Xuemei Jiang Yan Lin De Wu 《Journal of animal physiology and animal nutrition》2018,102(5):1340-1350
The study aimed to investigate the effects of maternal dietary methyl donors on the performance of sows and their offspring, and the associated hepatic insulin‐like growth factor‐1 (IGF‐1) expression of the offspring. A total of 24 multiparous sows were randomly fed the control (CON) or the CON diet supplemented with methyl donors (MD) at 3 g/kg betaine, 15 mg/kg folic acid, 400 mg/kg choline and 150 μg/kg VB12, from mating until delivery. After farrowing, sows were fed a common lactation diet through a 28‐days lactation period and six litters per treatment were selected to be fed until at approximately 110 kg BW. Maternal MD supplementation resulted in greater birthweight (p < 0.05) and increased the piglet weights (p < 0.01) and litter weights (p < 0.05) at the age of day 28, compared with that in CON group. The offspring pigs in the MD group had greater ADG (p < 0.05) and tended to lower F:G ratio (p = 0.07) compared with that of CON group from day 28 to 180 of age. The offspring pigs from MD group had greater serum IGF‐1 concentrations and expressions of hepatic IGF‐1 gene and muscular IGF‐1 receptor (IGF‐1r) protein at birth (p < 0.05), and greater hepatic IGF‐1 protein (p = 0.03) and muscular IGF‐1r gene expressions (p < 0.05) at slaughter, than that from the CON group. Moreover, the methylation at the promoter of IGF‐1 gene in the liver of newborn piglets and finishing pigs was greater in the MD group than that of the CON group (p < 0.05). In conclusion, maternal MD supplementation throughout gestation could enhance the birthweight and postnatal growth rate of offspring, associated with an increased expression of the IGF‐1 gene and IGF‐1r, as well as the altered DNA methylation of IGF‐1 gene promotor. 相似文献
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以浓硫酸为催化剂,采用甲醇-甘油复合溶剂,在高温高压的条件下对竹屑、杨木、桉木和松木进行液化,并且对液化产物进行了中和、过滤和旋转蒸发等一系列分级处理,并对液化固体残渣和气体产物进行分析。主要研究了以竹屑为原料的液化油的分级产物的组成及成分,研究结果表明:竹屑经甲醇-甘油液化,产物经过分级处理得到的主要产物为杂多酚、多糖苷和乙酰丙酸甲酯。多糖苷相主要含有多糖苷和未反应的甘油及其甘油聚合物,其中多糖苷主要为六元环吡喃糖苷,约占41.81%,甘油及其聚合物占47.27%;杂多酚相主要含有乙酰丙酸酯、杂多酚和甘油等化合物,其中甘油及其聚合物占38.04%,杂多酚相物质为难溶于水的焦油相的相对分子质量大的物质,约占杂多酚相的38.41%,并且杂多酚相的相对分子质量主要集中在990左右。 相似文献