砷胁迫下砷在生菜中迁移转化过程及其对营养元素含量的影响  

The Migration and Transformation Process of Arsenic and its Effect on Nutrient Content in Lettuce under Arsenic Stress

作　　者：张凤琳 姚顿 杨兆光[1] Zhang Fenglin(Center for Environment and Water Resources,Central South University,Changsha 410083,China)

机构地区：[1]中南大学环境与水资源研究中心,湖南长沙410083

出　　处：《安徽农学通报》2020年第5期18-21,共4页Anhui Agricultural Science Bulletin

基　　金：中南大学研究生科研创新项目(1053320182986);国家公益性行业(农业)科研专项(201503108);湖南省科技计划项目(2017WK2091)。

摘　　要：为探究砷胁迫下砷在生菜中的迁移转化过程及其对营养元素含量的影响,通过三价砷(As(Ⅲ))胁迫实验研究了各形态砷和营养元素在生菜中的分布特征。结果表明,生菜根部和叶部都仅检测到了As(Ⅲ)和五价砷(As(Ⅴ)),其中As(Ⅲ)为主要砷形态,分别在根和叶中占75%~85%、83%~87%。随着胁迫浓度的升高,根中As(Ⅲ)含量逐渐达到饱和,而As(Ⅴ)含量逐渐升高,叶中的As(Ⅲ)和As(Ⅴ)含量都显著升高。在高浓度胁迫下(10mg/L),BCFleaf/root突增3.7倍。与对照组相比,胁迫组根和叶中和Fe和Cu元素的含量并无显著变化,叶中Mn和Zn元素含量并无显著变化,根中Mn元素含量显著降低,根中Zn元素含量随胁迫浓度升高呈现出先升高后降低在升高的变化趋势。说明根对As(Ⅲ)的固定能力具有极限,当超过该极限时植物无法控制As(Ⅲ)向地上部分的迁移。另外,砷胁迫会影响Mn和Zn在根中的分布,生菜可以通过调控Mn和Zn的迁移来控制这些元素在叶中分布。To explore the migration and transformation process of arsenic and its effect on nutrient elements in lettuce under arsenic stress,the distribution characteristics of arsenic and nutrient elements in lettuce were studied through arsenic trivalent(As(Ⅲ))stress experiment.The results showed that only As(Ⅲ)and pentavalent arsenic(As(Ⅴ))were detected in the roots and leaves of lettuce,and As(Ⅲ)was the main form of arsenic,accounting for75-85%and 83-87%in the roots and leaves,respectively.With the increase of stress concentration,the content of As(Ⅲ)in roots gradually reached saturation,while the content of As(Ⅴ)gradually increased,and the content of As(Ⅲ)and As(Ⅴ)in leaves significantly increased.Under high concentration stress(10 mg/L),BCFleaf/root increased by3.7 times.Compared with the control group,the content of Fe and Cu in the root and leaves of the stress group did not change significantly,the content of Mn and Zn in the leaves did not change significantly.The content of Mn in the root decreased significantly,and the content of Zn in the root increased firstly,then decreased and then increased with the increase of stress concentration.The Studies have indicated that roots possess a limit to the fixation capacity of As(Ⅲ),and when this limit is exceeded,the plant can’t control the migration of As(Ⅲ)to the aboveground part.In addition,arsenic stress can affect the distribution of Mn and Zn in roots.Lettuce can control the distribution of these elements in leaves by regulating the migration of Mn and Zn.

关 键 词：砷 生菜 迁移转化 营养元素 

分 类 号：S636.2[农业科学—蔬菜学]