锑对水稻根生长的影响及锑的吸收动力学特性

EFFECT OF ANTIMONY ON ROOTS GROWTH AND KINETICS OF ANTIMONY UPTAKE BY RICE ROOTS

采用溶液培养法研究不同价态Sb对水稻根生长以及P和Sb交互作用对水稻根系吸收P、Sb的影响.试验结果表明,Sb(Ⅲ)和Sb(Ⅴ)对水稻根生长均有抑制作用,且随着溶液中Sb浓度的提高抑制效应越明显.水稻根系对Sb(Ⅲ)和Sb(Ⅴ)的吸收均可以用Freundich模型较好地模拟.水稻根系对不同价态Sb的吸收有明显差异.当溶液中Sb浓度为10μmol.l-1时,水稻根系对Sb(Ⅴ)的吸收比Sb(Ⅲ)减少70.9%,而Sb浓度为100μmol.l-1时,水稻根系对这两个价态的Sb吸收差异不大.P对水稻根系吸收Sb(Ⅲ)或Sb(Ⅴ)均没有影响.Sb(Ⅲ)可影响水稻根系对P的吸收,但是Sb(Ⅴ)对水稻根系吸收P影响不大.

Toxicity of antimony （Sb） to rice roots growth and kinetics of Sb uptake by rice roots in solution culture were studied. The results showed that Sb3＋ and Sb5＋ could inhibit rice roots growth and root length decreased as the Sb concentration in the solution increased. Uptake of Sb^3＋ and Sb^5＋ in rice roots could be simulated by Freundich model. There were significant differences of Sb uptake by rice roots between different Sb species in the solution. Uptake of Sb^5＋ by rice roots decreased 70.9% compared to that of Sb^3＋ for 10 mol·l^-1 Sb treatment,but no differences for Sb uptake were observed when these two Sb species were applied at the rate of 100 mol·l^-1. There were no significant differences for Sb3＋ and Sb^5＋ uptake by rice roots between P application and non-P application. Application of Sb^3＋ could affect P uptake by rice roots,while no differences for P uptake were observed for Sb^5＋ application.