Selenium enhances iron plaque formation by elevating the radial oxygen loss of roots to reduce cadmium accumulation in rice (Oryza sativa L.)

Gaoxiang Huang; Changfeng Ding; Yushan Li; Taolin Zhang; Xingxiang Wang

doi:10.1016/j.jhazmat.2020.122860

Selenium enhances iron plaque formation by elevating the radial oxygen loss of roots to reduce cadmium accumulation in rice (Oryza sativa L.)

J Hazard Mater. 2020 Nov 5:398:122860. doi: 10.1016/j.jhazmat.2020.122860. Epub 2020 May 17.

Authors

Gaoxiang Huang¹, Changfeng Ding², Yushan Li³, Taolin Zhang⁴, Xingxiang Wang⁵

Affiliations

¹ Ministry of Education's Key Laboratory of Poyang Lake Wetland and Watershed Research, School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, China; Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
² Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
³ Meteorological Service Center of Jiangxi, Nanchang 330046, China.
⁴ Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
⁵ Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; Ecological Experimental Station of Red Soil, Chinese Academy of Sciences, Yingtan 335211, China. Electronic address: xxwang@issas.ac.cn.

PMID: 32464560
DOI: 10.1016/j.jhazmat.2020.122860

Abstract

The inhibition of cadmium (Cd) absorption by selenium (Se) in rice may be associated with iron plaque (IP) formation, but the driving mechanisms are still unclear. This study investigated the effects of Se on the growth, oxidative toxicity, radial oxygen loss (ROL), IP formation, and Cd absorption of rice exposed to Cd. The results of this study showed that Cd stress elevated the levels of O₂- and H₂O₂ and depressed superoxide dismutase (SOD) and catalase (CAT) activities. The maximum ROL and IP were reduced by 43.3 % and 74.5 %, respectively. However, Se alleviated Cd toxicity by stimulating SOD and CAT activities by scavenging O₂- and H₂O₂ and enhancing the ROL profiles. Under culture conditions without Fe²⁺, Se had no impact on the total Cd levels in rice (T_Cd). However, with the addition of Fe²⁺, T_Cd was significantly reduced by 23.3 % due to the enhancement of IP formation by Se. These results indicated that Se can reduce Cd accumulation in rice in the presence of Fe²⁺ treatments. However, Se just alleviated Cd toxicity in the absence of Fe²⁺ treatments. The enhancement of ROL was a potential reason for the elevated IP formation induced by Se.

Keywords: Antioxidant enzyme; Barrier; Ferrous ion; Oxygen profile; Reactive oxygen species.

Publication types

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

MeSH terms

Cadmium / toxicity
Hydrogen Peroxide
Iron
Oryza*
Oxygen
Plant Roots
Selenium*

Substances

Cadmium
Hydrogen Peroxide
Iron
Selenium
Oxygen