Selenium toxicity in plants (Botanical Briefing)

Despite its toxicity in plants at higher levels, crops supply most of the essential dietary selenium in humans. Selenium toxicity in plants has been attributed to the formation of non-specific selenoproteins; however, this paradigm can be challenged now that there is increasingly abundant evidence suggesting that selenium-induced oxidative stress also contributes to toxicity in plants. Van Hoewyk provides an updated framework on plant selenium toxicity by indicating that both malformed selenoproteins and oxidative stress drive selenium-induced stress. Although challenging, distinguishing between these two distinct types of stress may be useful in the future development of crops with fortified levels of selenium.