Application and Effects of Rare Earth Elements in Agricultural Produc-tion Systems

Objective: To review the history of rare earths and their practical applications, as well as to identify the effects of some rare earths on crops. Design/methodology/approach: We performed an exhaustive review of the scientific literature related to the history of rare earth elements (REE), their chemical characteristics, composition in the Earth’s crust, and uses in industry, as well as of the effects of the light rare earth elements (LREE) on higher plants. The most relevant articles on the aforementioned topics of interest were then selected, analyzed, and discussed. Results: In recent years, the industrial and technological use of REE has increased significantly. Their use in the automotive, aeronautical, and space industries, in medicine, in renewable energies, and in electronic and military technology is resulting in the accumulation of these elements in the environment and their bioavailability for crops. Importantly, REE have been reported to have both stimulatory and inhibitory effects on biological systems, including plants. Limitations on study/implications: While some REE like lanthanum (La) and cerium (Ce) have been extensively studied, others have been scarcely explored and, therefore, little information has been published on them in the international literature. Findings/conclusions: The use of REE in technology, combined with poor waste management and recycling, cause contamination in soil and water, allowing REE bioavailability in plants. Further studies are needed to identify beneficial effects of REE in the face of biotic or abiotic stress factors.