Liu Dan, Li Song, Islam Ejazul, Chen Jun-ren, Wu Jia-sen, Ye Zheng-qian, Peng Dan-li, Yan Wen-bo, Lu Kou-ping
Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, School of Environmental and Resource Sciences, Zhejiang A & F University, Lin'an 311300, China; National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad 38000, Pakistan.
J Zhejiang Univ Sci B. 2015 Feb;16(2):123-30. doi: 10.1631/jzus.B1400107.
A hydroponics experiment was aimed at identifying the lead (Pb) tolerance and phytoremediation potential of Moso bamboo (Phyllostachys pubescens) seedlings grown under different Pb treatments. Experimental results indicated that at the highest Pb concentration (400 μmol/L), the growth of bamboo seedlings was inhibited and Pb concentrations in leaves, stems, and roots reached the maximum of 148.8, 482.2, and 4282.8 mg/kg, respectively. Scanning electron microscopy revealed that the excessive Pb caused decreased stomatal opening, formation of abundant inclusions in roots, and just a few inclusions in stems. The ultrastructural analysis using transmission electron microscopy revealed that the addition of excessive Pb caused abnormally shaped chloroplasts, disappearance of endoplasmic reticulum, shrinkage of nucleus and nucleolus, and loss of thylakoid membranes. Although ultrastructural analysis revealed some internal damage, even the plants exposed to 400 µmol/L Pb survived and no visual Pb toxicity symptoms such as necrosis and chlorosis were observed in these plants. Even at the highest Pb treatment, no significant difference was observed for the dry weight of stem compared with controls. It is suggested that use of Moso bamboo as an experimental material provides a new perspective for remediation of heavy metal contaminated soil owing to its high metal tolerance and greater biomass.
一项水培实验旨在确定在不同铅处理条件下生长的毛竹（Phyllostachys pubescens）幼苗对铅（Pb）的耐受性和植物修复潜力。实验结果表明，在最高铅浓度（400 μmol/L）下，竹苗生长受到抑制，叶片、茎和根中的铅浓度分别达到最大值148.8、482.2和4282.8 mg/kg。扫描电子显微镜显示，过量的铅导致气孔开度减小，根部形成大量内含物，而茎中只有少量内含物。使用透射电子显微镜进行的超微结构分析表明，添加过量铅会导致叶绿体形状异常、内质网消失、细胞核和核仁收缩以及类囊体膜丧失。尽管超微结构分析显示存在一些内部损伤，但即使是暴露于400 μmol/L铅的植物也存活下来，并且在这些植物中未观察到坏死和黄化等明显的铅毒性症状。即使在最高铅处理下，与对照相比，茎的干重也没有显著差异。由于毛竹具有高金属耐受性和更大的生物量，建议将其作为实验材料为重金属污染土壤的修复提供新的视角。
