Henk Schat

Abstract: Plants that accumulate metal and metalloid trace elements to extraordinarily high concentrations in their living biomass have inspired much research worldwide during the last decades. Hyperaccumulators have been recorded and experimentally confirmed for elements such as nickel, zinc, cadmium, manganese, arsenic and selenium. However, to date, hyperaccumulation of lead, copper, cobalt, chromium and thallium remain largely unconfirmed. Recent uses of the term in relation to rare-earth elements require critical evaluation. Since the mid-1970s the term ‘hyperaccumulator’ has been used millions of times by thousands of people, with varying degrees of precision, aptness and understanding that have not always corresponded with the views of the originators of the terminology and of the present authors. There is therefore a need to clarify the circumstances in which the term ‘hyperaccumulator’ is appropriate and to set out the conditions that should be met when the terms are used. We outline here the main considerations for establishing metal or metalloid hyperaccumulation status of plants, (re)define some of the terminology and note potential pitfalls. Unambiguous communication will require the international scientific community to adopt standard terminology and methods for confirming the reliability of analytical data in relation to metal and metalloid hyperaccumulators.

Abstract: Contents Summary 759 I. Hyperaccumulation: the phenomenon 759 II. Macroevolution of hyperaccumulation 760 III. Microevolution of hyperaccumulation: variation within hyperaccumulator species 760 IV. Genetic analysis of trace metal accumulation and tolerance 761 V. Mechanisms of trace metal accumulation 762 VI. General discussion and research perspectives 769 Acknowledgements 772 References 772 Summary Metal hyperaccumulator plants accumulate and detoxify extraordinarily high concentrations of metal ions in their shoots. Metal hyperaccumulation is a fascinating phenomenon, which has interested scientists for over a century. Hyperaccumulators constitute an exceptional biological material for understanding mechanisms regulating plant metal homeostasis as well as plant adaptation to extreme metallic environments. Our understanding of metal hyperaccumulation physiology has recently increased as a result of the development of molecular tools. This review presents key aspects of our current understanding of plant metal – in particular cadmium (Cd), nickel (Ni) and zinc (Zn) – hyperaccumulation.

TL;DR: Recent progress in understanding the mechanisms of As and Cd uptake and detoxification is presented, including the elucidation of why rice takes up so much arsenic from soil and of mechanisms of AS andCd hypertolerance.

TL;DR: In this paper, the authors investigated the growth performance of two populations of Silene dioica (Melandrium sylvestre), one from a copper mine and another from a non-mine soil.

TL;DR: In this article, the authors examined the transcription profiles of roots of Arabidopsis thaliana and T. caerulescens plants grown under deficient, sufficient, and excess supply of zinc.