Physiological and Biochemical Analysis of Selenium-Enriched Rice

Selenium is an essential trace element in the human body. However, its intake is generally low. Therefore, the production and utilisation of selenium-enriched foods is currently a research hotspot. In this study, the effects of low (0.2 mg<middle dot>kg-1), medium (1.0 mg<middle dot>kg-1), and high (5.0 mg<middle dot>kg-1) concentrations of selenium on the physiological and biochemical characteristics of rice were investigated to develop selenium-enriched rice. High concentrations of selenium have been found to inhibit the growth, physiology, and biochemistry of rice, while low concentrations of selenium promote its growth. The height of mature rice plants exposed to high concentrations of selenium was reduced by 7.20% compared with the height of control rice. Selenium decreased the proline content of rice during the growth period except in mature rice treated with medium and high concentrations of selenium. Excluding high concentrations, selenium treatment increased the soluble sugar content of rice from the tillering to the mature stages. The peroxidase activity of rice at the heading stage treated with medium levels of selenium was significantly higher than that of the control rice, while the superoxide dismutase activity of rice exposed to selenium was significantly enhanced at the mature stage. The malondialdehyde levels of mature rice treated with medium and high levels of selenium were significantly lower than those of the control rice. The selenium content of each plant part was significantly correlated with the soil selenium level. An increase in the soil selenium level facilitated the production of selenium-enriched rice.