title: [Effect of silicon on translocation and morphology distribution of lead in soil-tobacco system].
abstract: Taking tobacco as test material, a pot experiment was conducted to study the effect of silicon on translocation of lead (Pb) form soil to tobacco in order to explore effective measures for reducing Pb concentration in tobacco leaf. The results showed that silicon application promoted the transformation of exchangeable Pb into Fe-Mn oxide-bound Pb in non-rhizospheric soil, and into Fe-Mn oxide-bound Pb and residual Pb in rhizospheric soil, which decreased the availability and mobility of Pb in the soil. Silicon application significantly reduced the Pb uptake of tobacco, with the content of Pb being decreased by 6.5% to 44.0% in tobacco, and 3.1% to 60.4% in leaf. Silicon application promoted the transformation of ethanol-extractable, H2O-extractable Pb and NaCl-extractable Pb into HCl-extractable Pb and residual Pb in root, stem and leaf of tobacco, which reduced the toxicity and mobility of Pb in tobacco. Silicon restricted the transportation of Pb from soil to tobacco leaf by reducing the mobility index of Pb from soil to root and the mobility index of Pb from root to stem in soil-tobacco system. Meanwhile, the mobility index of Pb from stem to leaf in soil-tobacco system showed a rising-and-falling trend with the increase of Pb application. Silicon inhibited the Pb migration from soil to tobacco leaf by reducing availability of Pb, mitigating toxicity of Pb to tobacco, and changing the distribution of Pb forms in tobacco, consequently reducing Pb concentration of tobacco leaf. These results demonstrated silicon application could be effective in reducing translocation of Pb from soil to tobacco.
authors: Yi-Hua
authors: YH
authors: Yan
authors: Zi-Cheng
authors: ZC
authors: Zheng
authors: Ting-Xuan
authors: TX
authors: Li
authors: Xi-Zhou
authors: XZ
authors: Zhang
authors: Yong
authors: Y
authors: Wang
mesh_terms: D007854:Lead / Q000737:chemistry*; D010087:Oxides; D018515:Plant Leaves / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D012825:Silicon / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*; D014026:Nicotiana / Q000737:chemistry*
chemical_list: D010087:Oxides; D012987:Soil; D012989:Soil Pollutants; D007854:Lead; D012825:Silicon