水稻根系吸收砷的动力学特征及硅的缓解机制（Uptake Kinetics of Arsenic Species in Two Genotypes of Rice Plants and Mitigatory Mechanism of Silicon）

采用室内模拟的方法,研究了两种基因型水稻(硅突变体和野生型)根系吸收As的动力学特征以及Si对水稻吸收As的影响.结果表明,两种基因型水稻根系对As(III)和As(V)的吸收均可以用Freundlich模型较好地模拟.外源Si的加入可显著降低水稻根系对As(III)和As(V)的吸收.在20μmol·L-1As处理下,与不加Si处理相比,加1.0mmol·L-1Si处理导致水稻根系吸收As(III)和As(V)分别降低94.1%和92.2%(野生型);74.4%和90.2%(突变体).在100μmol·L-1As处理下,水稻根系吸收As(III)和As(V)则分别降低64.5%和91.2%(野生型);76.1%和90.6%(突变体).

Uptake Kinetics of Arsenic Species in Two Genotypes of Rice Plants and Mitigatory Mechanism of Silicon

Uptake kinetics of arsenic species in two genotypes of rice plants(Si mutant type and wild type)and the influence of Si on the uptake of As were studied using laboratory simulation experiments.Results showed that,the uptake of As(III)and As(V)in these two genotypes of rice could simulate by Freundlich model.Addition of Si in system could significantly reduce the uptake of As(III)and As(V)in rice root.Specifically,in 20μmol·L-1 As and 1.0mmol·L-1 Si treatment,the decreased percentage of the uptake of As(III)and As(V)in wild type rice was respectively 94.1% and 92.2%,and that was 74.4% and 90.2% for mutant type rice,compared with the control;In 100μmol·L-1 As and 1.0mmol·L-1 Si treatment,the decreased percentage of the uptake of As(III)and As(V)in wild type rice was respectively 64.5% and 91.2%,and that was 76.1% and 90.6% for mutant type rice.