A state-of-the-art review on cadmium uptake, toxicity, and tolerance in rice: From physiological response to remediation process

Cadmium (Cd), a major contaminant of concern, has been extensively reviewed and debated for its anthropo-genic global shifts. Cadmium levels in rice grains raise wide food safety concerns. The aim of this review is therefore to capture the dynamics of Cd in paddy soil, translocation pathways of Cd from soil to consumption rice, and assess its bio-accessibility in human consumption. In crop plants, Cd reduces absorption of nutrients and water, triggers oxidative stress, and inhibits plant metabolism. Understanding the mechanisms and behaviour of Cd in paddy soil and rice allows to explain, predict and intervene in Cd transferability from soil to grains and human exposure. Factors affecting Cd movement in soil, and further to rice grain, are elucidated. Recently, physiological and molecular understanding of Cd transport in rice plants have been advanced. Morphological -biochemical characteristics and Cd transporters of plants in such a movement were also highlighted. Ecologi-cally viable remediation approaches, including low input cost agronomic methods, phytoremediation and mi-crobial bioremediation methods, are emerging.

Automated summary

This review focuses on the dynamics of cadmium (Cd) in paddy soil, the translocation pathways from soil to rice consumption, and the bio-accessibility of Cd in human consumption. The factors affecting Cd movement in soil and its transfer to rice grains are elucidated. Ecologically viable remediation approaches and advances in understanding Cd transport in rice plants are also highlighted.