铅胁迫下硒处理的彩叶草根系和叶片的SEM/XRD 光谱学分析

 以彩叶草（Coleus blumei Benth.）为材料，在含1.0 mmol · L^-1 Pb ²⁺ 的营养液中直接添加不同 浓度（0.1、0.5、1.0、2.5、5.0 mg · L^-1）亚硒酸钠，利用X–射线衍射技术（XRD）和扫描电镜技术（SEM） 从光谱学角度初步探讨铅胁迫下不同浓度硒处理对彩叶草根系和叶片粉末的形态结构的影响。结果表明， 不同浓度硒对彩叶草根系和叶片粉末样品表面颗粒物微观形貌有较大影响，其中1.0 mg · L^-1 硒处理的 SEM 图中颗粒分布较其它浓度处理的均匀，结构紧密，成扁平褶状；XRD 衍射角向右移，强度、峰高、 峰面积和半高宽减小。这说明1.0 mg · L ^-1 的硒能降低溶液中铅的迁移和转化；颗粒的分布，衍射角的移 动，强度、峰高、峰面积和半高宽等变化说明彩叶草体内铅结合形态有所变化。

SEM and XRD Analyses of the Roots and Leaves of Coleus with Selenium Supplements Under Lead Stress

With coleus（Coleus blumei Benth.）for the materials，using the planting method with nutrient solution containing 1.0 mmol · L^-1 Pb ²⁺ and adding different concentrations（0.1，0.5，1.0，2.5， 5.0 mg · L^-1）sodium selenite，from the spectroscopy to study the effect of different selenium（Se） concentrations on the morphological and structural changes of Coleus under lead（Pb）stress by X-ray diffraction（XRD）and scanning electron microscope（SEM）analysis. The results showed that the particle microstructure in the roots and leaves of Coleus under Pb stress were great influenced by different Se concentrations，the particle distribution in the roots and leaves from the SEM image of 1.0 mg · L^-1 Se treatment was more uniform than the other concentration，and structure closer and flat plait shape，XRD diffraction angle moved to the right，and strength，high peak，peak area，and FWHM reduced. These indicated that 1.0 mg · L^-1 Se can reduce the migration and transformation of Pb in the solution，and explain the changes of combination form of Pb in the Coleus through the particle distribution，diffraction angle remove，the changes of strength，high peak，peak area and FWHM.