氯离子对玉米累积镉的影响

目的]氯离子能与土壤中的金属镉离子产生络合反应。土壤络合作用抑制镉在作物体内的毒害效应。研究镉胁迫下不同浓度的Cl-对玉米生长和累积镉能力的有效性。方法]模拟镉污染土壤盆栽玉米,当玉米长至2片真叶时,添加不同浓度的Cl-,培养2个月后收获,测定玉米形态、生物量和镉氯含量指标。结果]不同Cl-浓度处理后,玉米数量性状、生物量和镉的累积差异较显著,当Cl-浓度为200 mg/kg时,玉米株高和根长与对照相比分别从67.00和20.26 cm增加到81.33和31.67 cm,地上部与地下部生物量分别从38.39和7.38 mg/kg增加到69.10和25.17 mg/kg,玉米地上部和地下部累积镉的含量分别从30.47和20.57 mg/kg下降到22.50和7.11 mg/kg,累积Cl-含量分别从1.24和1.23 mg/kg下降到0.72和0.04 mg/kg,玉米地下部体内Cl-与Cd含量的相关系数达到0.893（P〈0.05）。结论]在土培试验条件下,一定浓度范围内的Cl-与镉的配合作用可以降低玉米对镉的吸收。

Effects of Chlorine Ion on Accumulation to Cadmium in the Maize

Objective]The chloride ion can produce complex reaction with cadmium ions in soils,soil complexation of cadmium toxicity inhibition in inside the object,under stress of Cd,different concentrations of chloride were added to study the effects of chlorine ion on the availability of Cd accumulation to maize under cadmium press.Method] In a pot culture experiment with maize by simulation of soil cadmium pollution, when the corn grew to two true leaf,different concentrations of Cl-was added,after two months,the maize was harvested. Maize of morphology,biomass,cadmium and chloride content were determined.Result]The results showed that the biomass and main quantity characteristics of maize increased significantly under 200 mg / kg concentrations of chlorine ion,stem plant height and root length of maize from 67 and 20. 26 cm to 81. 33 and 31. 67 cm,the shoot and root biomass of maize from 38. 39 and 7. 38 mg / kg to 69. 10 and 25. 17 mg / kg,respectively. The content of Cd in the shoots and roots of maize decreased under 200 mg / kg concentrations of chlorine ion,from 30. 47 and 20. 57 mg / kg to 22. 50 and 7. 11 mg / kg,the chloride concentrations in the shoots and roots from 1. 24 and 1. 23 mg / kg to 0. 72 and 0. 44 mg / kg. The correlation coefficient of Cd and Cl-in maize plant reached 0. 893（ P〈 0. 05）.Conclusion]The complexation of Cl-with cadmium reduced the uptake of Cd by the maize under the concentration range.