小飞蓬对Cd的耐性与吸收特性研究

目的]分析小飞蓬的生长、生理及富集重金属的能力,探索小飞蓬对Cd污染的生理响应机制与耐性机理。方法]采用水培试验方法,研究了5个Cd浓度(0、25、50、75、100μmol/L)处理对小飞蓬(赣南钨矿区优势植物)生长、叶绿素含量和吸收Cd的影响。结果]当Cd浓度为25和50μmol/L时小飞蓬能正常生长,各生长指标与对照(0μmol/L)相比差异均不显著。当Cd浓度达到75和100μmol/L时植物生长缓慢、植株矮小。小飞蓬对Cd吸收有很强的分异特征,能将更多重金属积累在植物地上部。小飞蓬地上部和根系的Cd含量随营养液Cd浓度的增加而增加,当Cd浓度为75μmol/L时,植物地上部Cd吸收总量达到最高,为118.87 mg。结论]小飞蓬对修复低、中浓度Cd污染的土壤具有一定潜力。

Tolerance and Adsorption Characteristic of Conyza canadensis to Cadmium

Objective] The purpose was to analyze the growth and physiology of Conyza canadensis L.and its ability on enriching heavy metal and explore its physiological response and tolerance mechanisms to Cd pollution.Method] The experimental method of water culture was used to study the influences of 5 concentration treatments(0,25,50,75 and 100 μmol/L) of Cd on the growth,chlorophyll content and Cd absorption of C.Canadensis(dominant plant in wolfram mine area of southern Jiangxi).Result] When Cd concentrations were 25 and 50 μmol/L,C.Canadensis could grow normally and compared with CK(0 μmol/L),the differences on various indices were not significant.When Cd concentration reached 75 and 100 μmol/L,the plant grew slowly and was small.C.Canadensis had very strong differentiation characteristics on Cd absorption and could accumulate more heavy metal in its aerial part.The Cd contents in the aerial part and root of C.Canadensis increased along with the increment of Cd concentration in nutrient solution.When Cd concentration was 75 μmol/L,the total quantity of Cd absorption in the aerial part of plant reached the highest of 118.87 mg.Conclusion]C.Canadensis had some potential on remedying the soil polluted by Cd with low and middle concentrations.