Emprego do silício como mitigador do estresse oxidativo causado pela arsênio em plantas de alface (Lactuca sativa L.)

Abstract

Lettuce is a vegetable of great economic importance in Brazil and its cultivation may be subject to contamination by potentially toxic elements such as arsenic (As). As affects all plant metabolism and causes the overproduction of reactive oxygen species (ROS) that can lead to oxidative stress. The application of silicon has shown promise in several crops in reducing the oxidative stress caused by As. However, until now, no study had been done with lettuce and, moreover, with the application of silicon nanoparticles (SiNP). The objective of this research was to evaluate the effect of As on the oxidative and antioxidant metabolism of lettuce plants and whether ionic silicon (Si) and/or nanoparticulate silicon (SiNP) is able to mitigate As stress in these plants. Markers of oxidative stress and antioxidant enzymes were evaluated. The results show that As caused the overproduction of ROS and lipid peroxidation and that silico, especially SiNP was able to reduce this damage by increasing antioxidant enzyme activity. It is concluded that silicon application can be employed to mitigate As stress in lettuce plants from the redox metabolism point of view.