Meharg Andrew A
School of Biological Sciences, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen, AB24 3UU, UK.
New Phytol. 2003 Jan;157(1):25-31. doi: 10.1046/j.1469-8137.2003.00541.x.
• A range of fern species (45) and their allies, Equisetum (5) and Selaginella (2) species and Psilotum nudum were screened for their ability to hyperaccumulate arsenic, to develop a phylogenetic understanding of this phenomenon. A number of varieties (5) of a known arsenic hyperaccumulator Pteris cretica were additionally included in this study. • This study is the first to report members of the Pteris genus that do not hyperaccumulate arsenic, Pteris straminea and tremula . • A phylogenetic basis for arsenic accumulation in ferns was investigated. Some orders can accumulate more arsenic than others. Although members of the Equisetales and Blechnales did not hyperaccumulate arsenic, they still accumulated relatively high levels in their fronds, approaching 100 mg kg when grown on a soil dosed with 100 mg kg arsenic. • Arsenic hyperaccumulation was identified as a phenomenon at the extreme range of fern arsenic accumulation. Ferns that exhibit arsenic hyperaccumulation arrived relatively late in terms of fern evolution, as this character is not exhibited by primitive ferns or their allies.
• 筛选了一系列蕨类植物物种（45种）及其近缘植物，包括木贼属（5种）、卷柏属（2种）植物以及松叶蕨，以研究它们超积累砷的能力，从而从系统发育角度理解这一现象。本研究还额外纳入了已知的砷超积累植物克里特凤尾蕨的多个变种（5个）。
• 本研究首次报道了凤尾蕨属中不超积累砷的成员，即条纹凤尾蕨和颤抖凤尾蕨。
• 研究了蕨类植物中砷积累的系统发育基础。一些目比其他目能积累更多的砷。虽然木贼目和乌毛蕨目的成员不超积累砷，但它们在叶片中仍积累了相对较高的水平，在添加了100毫克/千克砷的土壤中生长时，接近100毫克/千克。
• 砷超积累被确定为蕨类植物砷积累极端范围内的一种现象。表现出砷超积累的蕨类植物在蕨类植物进化过程中出现得相对较晚，因为原始蕨类植物及其近缘植物不具有这一特征。
