Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Plants, Soils, and Climate

Committee Chair(s)

Bruce Bugbee


Bruce Bugbee


Jeanette M. Norton


Paul R. Grossl


Silicone is a silicon-containing synthetic polymer. Silicon is a metalloid chemical element. Silicon is not considered an essential nutrient for plants, but it is typically abundant in soils and can be taken up in large amounts by plant roots. Silicon is known to have beneficial effects when added to the soil in which rice and several other plants are cultivated. These beneficial effects include disease and insect resistance, plant structural fortification, and regulation of the uptake of other plant nutrients. Silicic acid is the form of silicon in soils that is available to plants. In this study, the effect of silicic acid fertilization on the growth and drought tolerance of four crop plants (corn, wheat, soybean, and rice) was analyzed. Plants were cultivated in hydroponic solution and subjected to salt stress by the addition of salt to the hydroponic solution. Plants were also cultivated in a low-silicon soil-less medium (sphagnum peat moss) and subjected to drought stress by decreasing irrigation. Silicon fertilization generally improved drought and salt stress tolerance, but the effects were inconsistent. Silicon increased total corn plant mass by up to 20% and the effect was statistically significant (p<0.05) in two out of three techniques. Silicon increased water use efficiency (plant mass accumulated divided by mass of water used) in corn by up to 36% and the effect was statistically significant (p<0.05) in one out of four trials. Collectively, these results indicate an effect of silicon in drought and salinity stress tolerance, but additional studies on the rate and onset of drought are needed to determine interacting factors and better understand the inconsistent results.