Can As concentration in crop be controlled by Se fertilization? A meta-analysis and outline of As sequestration mechanisms

Authors: HAO, S - Southwest University; Banuelos, Gary; ZHOU, XINBIN - Southwest University

Submitted to: Plant and Soil
Publication Type: Review Article
Publication Acceptance Date: 5/11/2022
Publication Date: 5/16/2022
Citation: Hao, S., Banuelos, G.S., Zhou, X. 2022. Can As concentration in crop be controlled by Se fertilization? A meta-analysis and outline of As sequestration mechanisms. Plant and Soil. 838. Article 155967. https://doi.org/10.1016/j.scitotenv.2022.155967.
DOI: https://doi.org/10.1016/j.scitotenv.2022.155967

Interpretive Summary:

Technical Abstract: Arsenic (As) enters the soil through a variety of ways (mining activities, rainwater leaching, waste and sewage sludge discharge, and agricultural activities). It can be taken up by plants to enter the food chain, which poses a threat to human health. Rice is the main food source of As exposure in the world, especially in southeast and east Asia. For this reason, we are concentrating on rice in this review paper. Usually, As and selenium (Se) are coupled with each other in biogeochemical cycles since they have similar characteristics in absorption and transport from soil to plant. As (III) and Se (IV) usually predominate in anaerobic environments such as flooded paddy soils, whereas As (V) and Se (VI) are the main species present in aerobic soil conditions. As (III) and Se (IV) are transported into plant roots by phosphate transporters, while As (V) and Se (VI) are transported into plant roots by sulfate transporters. Thus, two different antagonisms can exist between inorganic Se and inorganic As uptake by plant roots. To gain a more quantitatively and systematically answer to these relationships, we evaluated data from the literature and used meta-analysis to evaluate interactions between Se and the uptake and accumulation of As in rice. Generally, others have shown that the addition of Se (IV) and Se (VI) to soils containing As decreased the accumulation of total As accumulation in plant roots and shoots, and consequently in rice grains. Our review clearly indicates that uptake mechanisms are involved in Se–As antagonism in rice. This information is useful for Se amended paddy soils that can produce simultaneously safe and enriched Se rice in As-contaminated rice paddy fields, as well as the potential danger of As accumulation when growing rice in Se-deficient paddy soils. These findings illustrate the role that Se can play in effectively alleviating the transfer of As to the human body through the rice food chain.