锶、铯、铀对5种植物种子发芽的影响

Influence of Strontium,Cesium,Uranium Upon the Seed Germination of Five Plants

利用0、0.1、0.5、1.0、2.5、5.0、7.5、10.0 mmol/L的硝酸锶(Sr)、硝酸铯(Cs)和硝酸铀(U)对向日葵、大豆、油菜、玉米和黄瓜进行发芽试验,研究核素对植物种子发芽的影响,为植物修复提供依据。结果表明:不同核素对植物种子发芽有不同影响,抑制影响的大小依次为U>Sr>Cs。核素、核素浓度、植物及其互作对种子发芽率影响非常显著。不同植物对核素的反应不同。玉米种子发芽率对Sr、Cs、U的反应不敏感。向日葵、油菜和黄瓜发芽率随Sr和Cs及其浓度的变化很小,但随U浓度变化很大。大豆发芽率随Sr、Cs、U及其浓度有一个波动变化。一般而言,核素浓度与植物种子发芽率有极显著的负相关关系(r=-0.928 9**),但不同核素和不同植物的相关程度不同。整体而言,核素浓度小于0.5 mmol/L能促进植物种子发芽,大于1.0 mmol/L会抑制种子发芽,Sr,Cs、U对植物种子发芽率影响的浓度效应不同。

A germination test of sunflower, soybean, rape, corn and cucumber seeds treated with 0,0.1,0.5, 1.0,2.5,5.0,7.5,10.0 mmol/L concentrations of strontium （Sr） nitrate, cesium （Cs） nitrate and uranium （U） nitrate was conducted to study the effects of nuclides on the seed germination of plants and provide the basess for phytoremediation. Results indicate that nuclides and their concentrations influence upon the seed germination rates of plants, and the influences of uranium is more than those of strontium and cesium. The influences of nuclide, concentrations and their interaction upon seed germination rates are very significant. The seed germination rate of corn has a little change to Sr, Cs, U and their concentrations. Those of sunflower, rape and cucumber have a little change to Sr, Cs and their concentrations, but a big change to U and its concentra- tions. That of soybean has a fluctuation change to Sr, Cs, U and their concentrations. There is very signficant negative correlation（r = -0. 928 9 ＊ ＊ ） between nuclide concentration and germination rate of plant seeds in general, but the relevance of differen nuclides and plants are different. The effects of plants, plants x nuclides, plants x concentrations and plants x nuclides x concentrations upon seed germination rates all are very signifi- cant. The low nuclide concentration less than 0.5 mmol/L can promote seed germination of plants, and the nuclide concentrations more than 1.0 mmol/L would decrease seed germination rates on the whole. The effects of concentrations of Sr, Cs and U on the germination rate of plant seeds are different.