镉在莲各器官中累积规律的研究

Research on the accumulation of cadmium in lotus(Nelumbo nucifera Gaertn.)organs

莲子是我国重要的特产优质资源,但莲等水生植物容易吸收积累重金属。为了探究莲对重金属镉的吸收积累特点,利用盆栽外施不同浓度的镉(0,1.0 mg·kg-1,2.5 mg·kg^(-1))培养两个莲子品种,检测分析镉对莲子生物量的影响及莲各器官中镉的含量。结果表明:随着外施镉浓度的增加,两种莲子生物量下降,各器官中镉含量增加,且与土壤镉含量呈正相关。各器官中镉含量差异明显,根部镉含量最高,莲壳中最低。根据GB 2762-2017,当镉浓度为1 mg·kg^(-1)时,莲子中镉含量符合食品中污染物限量标准,故莲可以在镉低污染区域种植。

Lotus(Nelumbo nucifera Gaertn.)seed is an important high-quality local product resource in China,but lotus is easy to absorb and accumulate heavy metals.In order to explore the absorption and accumulation of cadmium(Cd)in lotus,two cultivars of lotus were cultivated with different concentrations of Cd(0,1.0 mg·kg^(-1),2.5 mg·kg^(-1))in the pot.The effects of Cd on the lotus seed biomass and Cd contents in each organ of lotus were detected and analyzed.The results showed that,with the increase of Cd concentration,the biomass of the two lotus seeds decreased and Cd content in each organ increased,which was positively correlated with Cd content in soil.Cd content in each organ was different obviously.Cd content in root was the highest and that in lotus shell was the lowest.According to GB 2762-2017,when Cd concentration is 1 mg·kg^(-1),Cd content in lotus seed conforms to the pollutant limit standard in food,so lotus can be planted in the area with low Cd pollution.