Location: Sustainable Perennial Crops LaboratoryTitle: Morphological and physiological responses of plants to cadmium toxicity: A review
|HE, SHANYING - Zhejian University|
|YANG, XIAOE - Zhejiang University|
|HE, ZHENLI - University Of Florida|
Submitted to: Pedosphere
Publication Type: Review Article
Publication Acceptance Date: 4/30/2017
Publication Date: 7/1/2017
Citation: He, S., Yang, X., He, Z., Baligar, V.C. 2017. Morphological and physiological responses of plants to cadmium toxicity: A review. Pedosphere. 27(3):421–438.
Technical Abstract: Since the dawn of industrial revolution, anthropogenic activities have accelerated release of hazardous heavy metals, such as cadmium (Cd), copper (Cu), lead (Pb), chromium (Cr) and mercury (Hg) to the environment. Cadmium is toxic to animals and plants. Its bioaccumulation in food chain has surpassed all other toxic metals because of its high mobility in soils-. In recent years, extensive studies have been conducted to develop technologies for cleanup of Cd contaminated soils. Phytoremediation has been particularly scrutinized because of its being cost-effective and environmentally friendly. In theory, use of hyperaccumulator plants can substantially enhance remediation efficiency as these plants are able to tolerate and accumulate Cd more than 100 mg kg-1 dry weight (DW) (0.01%) in shoot, which is more than 100 times higher than non-hyperaccumulator plants. However, only a few plant species have this exceptional ability. Up to now, few plant species have been identified as Cd hyperaccumulators. Furthermore, despite their exceptional ability of tolerating and accumulating high concentrations of metals, none of the identified Cd hyperaccumulators has met the criteria for efficient phytoextraction. Consequently, increased interest has been directed to the non-hyperaccumulator plant species with fast growing habit, high biomass yield and desired Cd-accumulating capacity. The primary objective of this review is to compare hyperaccumulators with non-accumulating plants in their response to Cd stress and the related morphological, physiological and biochemical mechanisms so as to shed light for genetic engineering of hyperaccumulator plants and field application of phytoremediation.