Journal Article

Integrated physiological and metabolomic responses reveal mechanisms of Cd tolerance and detoxification in kenaf (Hibiscus cannabinus L.) under Cd stress

Mubeen, Samavia, Luo, Dengjie, Pan, Jiao, Li, Yun, Saeed, Wajid, Chen, Peng, Liu, Pingwu, Fang, Wangqiang, Rehman, Muzammal

2024

Overview

Cadmium (Cd) is a highly toxic trace element that occurs in large quantities in agricultural soils. The cultivation of industrial crops with high phytoremediation potential, such as kenaf, could effectively reduce soil Cd contamination, but the mechanisms of toxicity, tolerance, and detoxification remain unclear. In this study, the effects of different Cd concentrations (0, 100, 250, and 400 µM) on growth, biomass, Cd uptake, physiological parameters, metabolites and gene expression response of kenaf were investigated in a hydroponic experiment. The results showed that Cd stress significantly altered the ability of kenaf to accumulate and transport Cd; increased the activity of hydrogen peroxide (H O ), superoxide anion (O ), and malondialdehyde (MDA); reduced the activities of superoxide dismutase SOD) and catalase (CAT); and decreased the content of photosynthetic pigments, resulting in significant changes in growth and biomass production. Exposure to Cd was found to have a detrimental effect on the ascorbate-glutathione (AsA-GSH) cycle in the roots, whereas it resulted in an elevation in AsA levels and a reduction in GSH levels in the leaves. The increased content of cell wall polysaccharides under Cd stress could contribute to Cd retention in roots and limited Cd transport to above-ground plant tissues. Metabolomic analyses revealed that alanine, aspartate, and glutamate metabolism, oxidative phosphorylation, ABC transporter, and carbon metabolism were the major metabolic pathways associated with Cd stress tolerance. Cd stress increased gene expression of and in roots, which resulted in kenaf roots accumulating high Cd concentrations. This study extends our knowledge of the factors regulating the response of kenaf to Cd stress. This work provided a physiological and metabolomic perspective on the mechanism controlling the response of kenaf to Cd stress.

• Publisher: Frontiers Media SA,Frontiers Media S.A
• Subject: ABC transporter / Acids / Agricultural land / Alanine / Ascorbic acid / Biomass / Cadmium / Catalase / Cd stress / Cell walls / Chlorophyll / Detoxification / Gene expression / Glutathione / heavy metal tolerance / Heavy metals / Hibiscus cannabinus / Hibiscus cannabinus L. (kenaf) / Hydrogen peroxide / Hydroponics / Industrial crops / Kenaf / Leaves / Metabolic pathways / Metabolites / Metabolomics / Oxidative metabolism / Oxidative phosphorylation / Oxidative stress / Phosphorylation / Photosynthetic pigments / Physiology / Phytoremediation / Plant Science / Plant tissues / Polysaccharides / R&D / Research & development / Roots / Saccharides / Seeds / Soil contamination / Soil pollution / stress physiology / Superoxide anions / Superoxide dismutase / Toxicity / Toxicity tolerance / Trace elements