硒在不同品种甘薯茎块中的累积特征及其与重金属互作的规律研究

Study on Accumulation of Selenium in Sweet Potato and Its Interation with Heavy Metals

以闽西富硒地区某流域为研究区域,采集区域内4个品种的甘薯样品及其对应的土壤样品,通过分析土壤的理化性质、土壤和甘薯的硒含量和重金属含量,研究了硒在土壤—甘薯系统中的转移特征及其影响因素。结果表明:该流域种植甘薯的土壤全硒含量平均值为0.206 mg/kg,其中8.33%的点位处于缺硒水平,33.33%的点位处于潜在缺硒水平,55.00%的点位处于足硒水平,3.33%的点位处于富硒水平;4个甘薯品种中硒的平均含量表现为:龙薯15(2.49μg/kg)>金山630(1.91μg/kg)>金山57(1.46μg/kg)>福宁紫3号(0.86μg/kg);4个甘薯品种中仅龙薯15不存在重金属污染,且龙薯15的富硒能力要优于其他3个甘薯品种;甘薯硒含量与土壤的全硒含量、pH值、有机质含量及甘薯砷含量呈显著正相关,与甘薯铅含量呈显著负相关。综上,龙薯15对硒的富集能力最强,且不存在重金属超标样品,适合在富硒地区进行推广种植。

Taking a Se-rich area of western Fujian as the study area,the samples of 4 sweet potato(Ipomoea batatas L.)varieties and corresponding soil samples were collected in the area.The physical and chemical properties of soils and the contents of Se and heavy metals in soils and sweet potatoes were analyzed.and the migration characteristics and influencing factors of selenium in soil and sweet potato system were studied.The results showed that the average Se content of sweet potato growing soil in this area was 0.206 mg/kg,with 8.33%at Se deficiency level,33.33%at potential Se deficiency level,55.00%at sufficient Se level and 3.33%at Se-rich level.The average Se contents in four sweet potato varieties were as follows:Longshu 15(2.49μg/kg)>Jinshan 630(1.91μg/kg)>Jinshan 57(1.46μg/kg)>Funingzi 3(0.86μg/kg).Se content in sweet potato was positively correlated with soil Se content,pH,organic matter content and arsenic content in sweet potato,and negatively correlated with lead content in sweet potato.Longshu 15 has the strongest enrichment ability of Se,and the content of heavy metals in Longshu 15 was lower than the limit of national standards for food safety.In conolusion,Longshu 15 is suitable for planting in Se-rich soil.