Study on the Migration and Accumulation of Selenium between Soil and Vegetations

Selenium (Se) is an essential trace element for human health, and humans mainly consume Se through diet. China is recognized as a Se-deficient country, and the study of Se migration and accumulation relationships between crops and soils is essential for Se-deficient areas. In this experiment, the greenhouse pot experiment of Chinese cabbage (Brassica rapa L. ssp. pekinensis), wheat (Triticum aestivum L.) and pepper (Capsicum annuum L.) were carried out with the Guanzhong region of Shaanxi Province and common farmland soils from Beijing Province. The relationship between the Se content in soil and crops organs (e.g., roots, stems, leaves, grain and fruit) and the differences in the Se-enriching capacity of the organs were analyzed. The following results were obtained: (1) all three field crops could absorb Se from soil, including Se-rich and -regulated soil and reach the standard of Se-enriched vegetables; (2) different organs of Chinese cabbage had different Se-enriching capacity, which can be arranged as leaf > stem > root, while the Se enrichment capacity of wheat was root > leaf > stem > grain, and for pepper it was root > leaf > fruit > stem; (3) when the soil Se regulation content reached 1.0–1.5 mg/kg, the utilization rate of Se in Chinese cabbage and pepper were higher, but when the soil Se regulation reached 4.0–5.0 mg/kg, the utilization rate of Se in wheat was higher.