铅(Pb)在凤眼莲(Eichhornia Crassipes Solms)体细胞中分布的电镜观察  

Subcellular Localization of Pb in Cells of Eichhornia Crassipes Solms by Electron Microscopy

作　　者：徐勤松[1] 施国新[1] 王学[1] 丁秉中[1] 陈苏雅[1] 许丙军[1] 赵娟[1] 

机构地区：[1]南京师范大学生命科学学院,江苏南京210097

出　　处：《南京师大学报（自然科学版）》2006年第3期81-85,共5页Journal of Nanjing Normal University(Natural Science Edition)

基　　金：国家自然科学基金(30370083);江苏省教育厅自然科学基金(05KJB18006703KJB180062);江苏省重点实验室开放基金;南京师范大学科研启动基金资助项目

摘　　要：用10 mg/L和100 mg/L浓度的Pb(NO3)2培养10 d的凤眼莲为实验材料,用透射电镜观察了重金属Pb在其细胞内的分布及造成的结构损伤情况.定位结果显示:在10 mg/L浓度处理的凤眼莲植株中,Pb颗粒主要沉积在根上:根的表面、胞间隙、细胞壁、细胞膜和液泡,没有观察到明显的细胞器超微结构损伤,而在叶细胞中则没有观察到颗粒分布.随处理浓度增大(100 mg/L),Pb在根细胞各细胞组分中明显增多,对细胞的损伤亦加剧,表现为:质体解体和染色质凝集.同时,一部分Pb被运输到茎叶部分,主要分布在叶细胞的细胞膜、液泡内和叶绿体上,而在根和叶的其它细胞器都没有观察到颗粒分布.同时,各Pb处理浓度都没对叶细胞超微结构产生破坏.我们的观察结果证明凤眼莲抗重金属Pb的重要耐性机制是:根对重金属的积累,细胞壁的金属沉淀作用和液泡的区域化作用等.Distribution of Pb in leaf and root tip cells of Eichhornia Crassipes Solms treated with Pb （NO3）：for 10 is observed bv transmission electron microscope. Localization results show that when treated with 10mg/L Pb, Pb deposit is mainly accumulated in the root： on the root surface, in intracellular space, cell membrane, vacuole, and no perceptible uhrastructural damages are induced by Pb, while a negative phenomenon is observed in leaf cells. With increasing pollutant concentration （100 mg/L） , the content of Pb in every, cellular component of root tip cell increases markedly, the injury to root cell is more serious compared with low concentration, such as disintegration of plasmid and agglutination of chromatin. Meanwhile, a little portion of Pb is transported to stem and leaf, and the granule of Pb mainly is distribu- ted in cell membrane, vacuole and chloroplasts, and no injury, to leaf cell is induced by the exposing concentration of Pb. No particle is distributed in other cell organelles. The important resistance mechanism of plants confirmed by our observation results is accumulation of heavy metal in root, deposit of heavy metal in cell wall and compartment of heavy metal in vacuole,etc.

关 键 词：重金属 PB 风眼莲 亚细胞定位 

分 类 号：Q944[生物学—植物学]