Plant samples of Cardamine hupingshanesis (Brassicaceae), Ligulariafischeri (Ledeb.) turcz (Steraceae) and their underlying top sediments were collected from selenium (Se) mine drainage areas in Enshi, China. Concentrations of total Se were measured using Hydride Generation-Atomic Fluorescence Spectrometry (HG-AFS) and Se speciation were determined using liquid chromatography/UV irradiation-hydride generation-atomic fluorescence spectrometry (LC-UV-HG-AFS). The results showed that C. hupingshanesis could accumulate Se to 239±201 mg/kg DW in roots, 316±184 mg/kg DW in stems, and 380±323 mg/kg DW in leaves, which identifies it as Se secondary accumulator. Particularly, it could accumulate Se up to 1965±271 mg/kg DW in leaves, 1787±167 mg/kg DW in stem and 4414±3446 mg/kg DW in roots, living near Se mine tailing. Moreover, over 70% of the total Se accumulated in C. hupingshanesis were in the form of selenocystine (SeCys2), increasing with increased total Se concentration in plant, in contrast to selenomethionine (SeMet) in non-accumulators (eg. Arabidopsis) and secondary accumulators (eg. Brassica juncea), and selenomethylcysteine (SeMeCys) in hyperaccumulators (eg. Stanleya pinnata). There is no convincing explanation on SeCys2 accumulation in C. hupingshanesis based on current Se metabolism theory in higher plants, and further study will be needed.
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机译：从中国恩施的硒（Se）矿山流域收集了虎杖胺类植物（十字花科），Li草（Ledeb。turcz（Steraceae）的植物样品及其下层顶部沉积物。使用氢化物发生-原子荧光光谱法（HG-AFS）测量总硒的浓度，并使用液相色谱/紫外辐射-氢化物发生-原子荧光光谱法（LC-UV-HG-AFS）测定硒的形态。结果表明，虎杖山毛虫在根部的硒累积量为239±201 mg / kg DW，茎中的硒累积量为316±184 mg / kg DW，在叶片中的硒累积量为380±323 mg / kg DW，被鉴定为Se的二次积累。特别是，它可以在硒矿尾矿附近积累高达1965±271 mg / kg DW的硒，茎中1787±167 mg / kg DW的根和4414±3446 mg / kg DW的硒。此外，与非蓄积性植物（如拟南芥）和非蓄积性植物中的硒蛋氨酸（SeMet）相反，在壶坪山毛孢菌中累积的总硒中有70％以上是以硒代半胱氨酸（SeCys2）的形式出现的，并随着植物总硒浓度的增加而增加。次蓄积器（例如芥菜）和超蓄积器中的硒甲基半胱氨酸（SeMeCys）（例如赤松）。基于目前高等植物的硒代谢理论，尚无令人信服的关于虎耳山毛孢菌中SeCys2积累的解释，有待进一步研究。
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