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

Journal of Hazardous Materials

https://doi.org/10.1016/j.jhazmat.2021.127947

Published: 5 March 2022

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.