目的运用DNA条形码技术准确快速鉴定中药材钩藤属植物及其近缘物种。方法利用DNA试剂盒快速提取钩藤属样品的DNA基因组,PCR扩增DNA并进行双向测序,采用CodonCode Aligner V 6.0.2对测序峰图进行校对拼接,并使用MEGA6.0进行序列比对,构建...目的运用DNA条形码技术准确快速鉴定中药材钩藤属植物及其近缘物种。方法利用DNA试剂盒快速提取钩藤属样品的DNA基因组,PCR扩增DNA并进行双向测序,采用CodonCode Aligner V 6.0.2对测序峰图进行校对拼接,并使用MEGA6.0进行序列比对,构建其NJTree进行聚类分析,再与GenBank库中现有的相应钩藤属ITS2序列相比较,从而鉴定并归属样品。结果 6种钩藤属植物的ITS2序列长度在220~224 bp,其K2P遗传距离为0~0.020,并且各个钩藤属植物之间均有不同的变异位点。经与GenBank数据库进行比对并建其NJTree,结果表明ITS2序列可区分钩藤属及其近缘植物(攀茎钩藤)。结论 ITS2序列作为DNA条形码可对茜草科钩藤属植物进行快速、有效地鉴定,为市场上钩藤品质提供可靠的科学依据。展开更多
Heavy metal pollution in agricultural soils has serious negative influence on human health. Concentrations of Cd, Hg, As, Pb, Cr, Cu, Zn, and Ni in top soils （0-20 cm） of greenhouses and farmlands from four main veg...Heavy metal pollution in agricultural soils has serious negative influence on human health. Concentrations of Cd, Hg, As, Pb, Cr, Cu, Zn, and Ni in top soils （0-20 cm） of greenhouses and farmlands from four main vegetable production areas Shouguang, Laiyang, Jinxiang, and Zhangqiu in Shandong Province, one of the most rapidly developing regions in China, were measured in this study. Shouguang is mainly occupied by greenhouse vegetables and the other three areas are mainly open field culture. Total of 149 soil samples were collected. The average concentrations of the eight heavy metals of the tested 149 soil samples were all below the threshold values according to ＂Farmland environmental quality evaluation standards for edible agricultural products （HJ332-2006）＂ of China. However, most of the studied heavy metals were present at higher concentrations than those of the natural background levels in local agricultural soils. Among the total 149 soil samples, 22 samples were contaminated by Cd, Ni, Cu, or Hg. Comparisons showed that the main pollution element in greenhouse vegetable soils was Cd, while that of open field vegetable soils was Cu. The results of principal components analysis （PCA） suggested that concentrations of Cr, As, and Ni were mainly controlled by parent rocks; Hg and Pb were affected by anthropogenic activities such as vehicle and industrial fumes and waste water irrigation. Meanwhile, concentrations of Cd, Cu, and Zn were affected mainly by the use of agrochemicals. Most of the heavy metals were positively correlated with each other in concentration. Appropriate measures should be taken to effectively control heavy metal levels in vegetable soils and thus protect human health.展开更多
基金supported by the National Key Tech-nology R&D Program of China (2006BAD17B07,2006BDA07A13-1-2) the Staring Fund for Doc-tors of Shandong Academy of Agricultural Sciences,China (2006YBS015)
文摘Heavy metal pollution in agricultural soils has serious negative influence on human health. Concentrations of Cd, Hg, As, Pb, Cr, Cu, Zn, and Ni in top soils （0-20 cm） of greenhouses and farmlands from four main vegetable production areas Shouguang, Laiyang, Jinxiang, and Zhangqiu in Shandong Province, one of the most rapidly developing regions in China, were measured in this study. Shouguang is mainly occupied by greenhouse vegetables and the other three areas are mainly open field culture. Total of 149 soil samples were collected. The average concentrations of the eight heavy metals of the tested 149 soil samples were all below the threshold values according to ＂Farmland environmental quality evaluation standards for edible agricultural products （HJ332-2006）＂ of China. However, most of the studied heavy metals were present at higher concentrations than those of the natural background levels in local agricultural soils. Among the total 149 soil samples, 22 samples were contaminated by Cd, Ni, Cu, or Hg. Comparisons showed that the main pollution element in greenhouse vegetable soils was Cd, while that of open field vegetable soils was Cu. The results of principal components analysis （PCA） suggested that concentrations of Cr, As, and Ni were mainly controlled by parent rocks; Hg and Pb were affected by anthropogenic activities such as vehicle and industrial fumes and waste water irrigation. Meanwhile, concentrations of Cd, Cu, and Zn were affected mainly by the use of agrochemicals. Most of the heavy metals were positively correlated with each other in concentration. Appropriate measures should be taken to effectively control heavy metal levels in vegetable soils and thus protect human health.
