三种蔬菜在2种硒含量土壤中对硒锌铅镉吸收规律的研究

Selenium, Lead, Cadmium and Zinc Uptake in Soils with Different Contents of Selenium of Three Types of Vegetables

采用盆栽试验,研究了叶用芥菜、大蒜和雍菜在富硒和低硒土壤中对硒和重金属（Pb、Cd、Zn）的吸收规律。结果表明：在富硒土壤中,大蒜、芥菜和雍菜各部位硒含量均高于低硒土壤的处理,其中,根部和可食部位分别是低硒土壤的1.6-2.6倍和1.1-4.5倍。3种蔬菜在两种土壤上的可食部位硒含量都表现出大蒜（0.029-0.143 mg/kg）〉芥菜（0.007-0.016 mg/kg）〉雍菜（0.002-0.007 mg/kg）的趋势,其中富硒土壤中大蒜和芥菜硒含量达到富硒标准（≥0.01mg/kg）。3种蔬菜的根部或鳞茎部位的硒含量均显著高于各自的茎或叶部位。蔬菜重金属含量与土壤重金属本底值呈正相关。3种蔬菜对Pb、Cd、Zn的吸收能力不同,植株的Pb含量高低顺序为雍菜〉芥菜〉大蒜,Cd含量高低顺序为大蒜〉芥菜〉雍菜,Zn含量高低顺序为芥菜〉大蒜〉雍菜,且在蔬菜不同部位的累积顺序均为根〉茎、叶。因此,生产安全且富硒蔬菜,需选择硒富集能力强且重金属吸收能力较低的蔬菜种类。本研究的结果表明,供试的3种蔬菜中,大蒜和芥菜具有较高的硒富集能力,可作为富硒蔬菜生产。

Selenium（Se） is a necessary trace element for human health. Soils with high content of Se are usually accompanied with high amounts of heavy metals, affecting the food safety of Se enriched crops. In this study, pot experiments were carried out to analyze the absorption characteristics of Se, lead（Pb）, cadmium（Cd） and zinc（Zn）in the Se-rich and Se-low soils, by planting mustard, garlic and spinach. Comparison with the Se-low soils, Se contents were higher in three kinds of vegetables in the Se-rich soils, 1.6-2.6 times in roots and 1.1-4.5 times in edible parts than those in the Se-low soils. The accumulation of Se in edible parts showed the order of garlic（0.029-0.143 mg/kg）, mustard（0.007-0.016 mg/kg）, and spinach（0.002-0.007 mg/kg） in both soils. Se contents of garlic and mustard reached the Standards of Se-rich Food in Se-rich soils, and in root and bulb of three vegetables were significantly higher than in the stem and leaf. The contents of heavy metals（ Pb, Cd, Zn） in vegetables were positively correlated with the soil background values. The absorption capacities of Pb, Cd, Zn were different in three vegetables. The Pb contents were followed by spinach mustard garlic, Cd contents by garlic mustardspinach, Zn contents by mustardgarlicspinach, respectively. The accumulations of heavy metals in roots were higher than those in stems and leaves. Therefore, the production of safety and Se-enriched vegetables,vegetables species with both strong Se enrichment capability and low heavy metal absorption ability should beconsidered. The results showed that garlic and mustard were the most suitable species among three tested vegetables, could be used for Se-rich vegetable production.