Ammonium has stronger Cd detoxification ability than nitrate by reducing Cd influx and increasing Cd fixation in Solanum nigrum L

Lu-Dan Zhang; Xiang Liu; Ming-Yue Wei; Ze-Jun Guo; Zhi-Zhu Zhao; Chang-Hao Gao; Jing Li; Jian-Xin Xu; Zhi-Jun Shen; Hai-Lei Zheng

doi:10.1016/j.jhazmat.2021.127947

Ammonium has stronger Cd detoxification ability than nitrate by reducing Cd influx and increasing Cd fixation in Solanum nigrum L

J Hazard Mater. 2022 Mar 5:425:127947. doi: 10.1016/j.jhazmat.2021.127947. Epub 2021 Dec 1.

Authors

Affiliations

¹ Key Laboratory for Subtropical Wetland Ecosystem Research of MOE, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian 361005, PR China.
² Key Laboratory for Subtropical Wetland Ecosystem Research of MOE, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian 361005, PR China; Taiyuan University of Technology, Taiyuan, Shanxi 030024, PR China.
³ Key Laboratory for Subtropical Wetland Ecosystem Research of MOE, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian 361005, PR China. Electronic address: zhenghl@xmu.edu.cn.

PMID: 34896722
DOI: 10.1016/j.jhazmat.2021.127947

Abstract

Cadmium (Cd) is a harmful heavy metal that affects the growth and development of plants. Nitrogen (N) is an essential nutrient for plants, and appropriate N management can improve Cd tolerance. The aim of our study was to explore the effects of different forms of N on the molecular and physiological responses of the hyperaccumulator Solanum nigrum to Cd toxicity. Measurement of biomass, photosynthetic parameters, and Cd²⁺ fluxes using non-invasive micro-test technique, Cd fluorescent dying, biochemical methods and quantitative real-time PCR analysis were performed in our study. Our results showed that ammonium (NH₄⁺) has stronger Cd detoxification ability than nitrate (NO₃^-), which are likely attributed to the following three reasons: (1) NH₄⁺ decreased the influx and accumulation of Cd²⁺ by regulating the transcription of Cd transport-related genes; (2) the ameliorative effects of NH₄⁺ were accompanied by the increased retention of Cd in the cell walls of roots; and (3) NH₄⁺ up-regulated SnExp expression.

Keywords: Cd transport-related genes; Cd(2+) influx; H(+) influx; Nitrogen forms; Phytoremediation regulation.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Ammonium Compounds*
Biodegradation, Environmental
Cadmium / analysis
Cadmium / toxicity
Nitrates
Plant Roots / chemistry
Soil Pollutants* / analysis
Solanum nigrum*

Substances

Ammonium Compounds
Nitrates
Soil Pollutants
Cadmium