Lead (Pb) is a harmful pollutant that disrupts normal functions from the cell to organ levels. Salix babylonica is characterized by high biomass productivity, high transpiration rates, and species specific Pb. Better understanding the accumulating and transporting Pb capability in shoots and roots of S. babylonica, the toxic effects of Pb and the subcellular distribution of Pb is very important. Pb exerted inhibitory effects on the roots and shoots growth at all Pb concentrations. According to the results utilizing inductively coupled plasma atomic emission spectrometry (ICP-AES), S. babylonica can be considered as a plant with great phytoextraction potentials as translocation factor (TF) value > 1 is observed in all treatment groups throughout the experiment. The Leadmium™ Green AM dye test results indicated that Pb ions initially entered elongation zone cells and accumulated in this area. Then, ions were gradually accumulated in the meristem zone. After 24 h of Pb exposure, Pb accumulated in the meristem zone. The scanning electron microscopy (SEM) and energy-dispersive X-ray analyses (EDXA) results confirmed the fluorescent probe observations and indicated that Pb was localized to the cell wall and cytoplasm. In transverse sections of the mature zone, Pb levels in the cell wall and cytoplasm of epidermal cells was the lowest compared to cortical and vessel cells, and an increasing trend in Pb content was detected in cortical cells from the epidermis to vascular cylinder. Similar results were shown in the Pb content in the cell wall and cytoplasm of the transverse sections of the meristem. Cell damage in the roots exposed to Pb was detected by propidium iodide (PI) staining, which was in agreement with the findings of Pb absorption in different zones of S. babylonica roots under Pb stress. S. babylonica L. is observed as a plant with great potential of Pb-accumulation and Pb-tolerance. The information obtained here of Pb accumulation and localization in S. babylonica roots can furthers our understanding of Pb-induced toxicity and its tolerance mechanisms, which will provide valuable and scientific information to phytoremediation investigations of other woody plants under Pb stress.

中文翻译：

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柳柳根的铅积累和定位中的早期响应的表征。

铅（Pb）是有害的污染物，会破坏从细胞到器官水平的正常功能。幼柳的特点是生物量高，蒸腾速率高和物种特异性Pb。更好地了解婴儿链球菌根和茎中铅的积累和转运能力，铅的毒性作用和铅的亚细胞分布非常重要。铅在所有铅浓度下均对根和芽生长具有抑制作用。根据利用电感耦合等离子体原子发射光谱法（ICP-AES）得出的结果，在整个实验过程中所有处理组中均观察到易位因子（TF）值> 1，因此可以将小链霉菌视为具有高植物提取潜力的植物。Leadmium™Green AM染料测试结果表明，Pb离子最初进入延伸区的细胞并积累在该区域中。然后，离子逐渐聚集在分生组织区中。Pb暴露24 h后，Pb积累在分生组织区。扫描电子显微镜（SEM）和能量色散X射线分析（EDXA）结果证实了荧光探针的观察结果，并表明Pb定位于细胞壁和细胞质。在成熟区的横截面中，表皮细胞的细胞壁和细胞质中的Pb水平比皮层和血管细胞最低，并且从表皮到维管柱的皮层细胞中Pb含量呈上升趋势。在分生组织横切面的细胞壁和细胞质中的Pb含量也显示出相似的结果。碘化丙锭（PI）染色可检测出暴露于Pb根部的细胞损伤，这与在Pb胁迫下S. babylonica根部不同区域吸收Pb的发现是一致的。婴儿链球菌（S. babylonica L.）被认为是具有丰富的铅积累和耐铅能力的植物。此处获得的有关铅在婴儿链球菌根中的积累和定位的信息可以加深我们对铅诱导的毒性及其耐受机制的了解，这将为其他木本植物在铅胁迫下的植物修复研究提供有价值的科学信息。被认为是具有巨大的铅积累和耐铅能力的植物。此处获得的有关铅在婴儿链球菌根中的积累和定位的信息可以加深我们对铅诱导的毒性及其耐受机制的了解，这将为其他木本植物在铅胁迫下的植物修复研究提供有价值的科学信息。被认为是具有巨大的铅积累和耐铅能力的植物。此处获得的有关铅在婴儿链球菌根中的积累和定位的信息可以加深我们对铅诱导的毒性及其耐受机制的了解，这将为其他木本植物在铅胁迫下的植物修复研究提供有价值的科学信息。