Abstract

Silicon (Si) is taken up by plant roots as monosilicic acid from soil solution. Silicon has not been considered as an essential element for plant growth. Nevertheless, adequate Si supply alleviate the heavy metals, drought and nutrient deficiency stresses, as well as it increases the root volume and promotes the production antioxidants and phenols compounds, which are related with plant defence mechanisms and structural support. The general objective of this research was to study Si uptake and antioxidant performance of ryegrass cultivars grown under different Si -doses and -sources. A greenhouse experiment was conducted on pots filled with an Andisol of Southern Chile by using three ryegrass (Lolium perenne L.) cultivars (Aries, Jumbo and Pastoral) fertilized either with calcium silicate or sodium silicate at increasing Si doses (0, 250, 500 or 1000 mg Si/kg soil). At harvest, the dry weight (DW) and Si concentration of shoots and roots will be determined on samples of two consecutive cuts. In addition, antioxidant enzymes (superoxide dismutase, peroxidase and ascorbate peroxidase) and phenols concentration will be assayed; lipid peroxidation will be monitored in plant tissues as an index of oxidative damage. Acknowledgments: Project FONDECYT N° 1120901