矿区不同重金属污染梯度下芒草叶绿体及其它超微结构的变化

Variety of Chloroplast and Other Ultrastructures in the Leaves of Miscanthus sinensis in Mining Area

植物超微结构是反映环境状况的敏感指标,大量被用于重金属污染的毒性实验与其它环境胁迫的研究中。但对长期在重金属污染环境中的植物超微结构的研究还很少见。在金属矿区自然形成的不同重金属污染梯度的环境背景下,选择在遗传上对环境胁迫比较敏感的芒草M iscanthus sinensis为研究对象,探讨经历不同强度胁迫的芒草在叶片超微结构上的变化。结果表明:重金属污染促使叶片的维管束鞘相对发达;重度污染下的叶绿体冬季解体提前,叶绿体淀粉粒的积累量对不同重金属污染浓度的反应表现出不同机制;高重金属污染下的细胞壁内沉淀了大量的黑色物质,推测是重度胁迫下诱导产生的次生代谢物质。

Ultrastructure of plant, sensitive to environment, is widely used in controlled experiment to evaluate endurance of plant species or variety to environment press. But it is rarely used in field researches. Miscanthus sinensis was proved to be sensitive to environment on genetic level. In this research, 5 populations growing in mining area polluted with different heavy metal gradients and one unpolluted population outside were studied. Obvious variety was observed in the ultrastructure of M. sirtensis leaves in different heavy metal grads, mainly including the structure of vascular bundle, the shape and structure of chloroplast in bundle cells, the number of starch et al.