The Effects of Salicylic Acid on the Production of Hydrogen Peroxide in Physcomitrella patens

Indianapolis, IN

Reactive Oxygen Species (ROS) were originally believed to be toxic to plants and were thought to cause apoptosis in cells. However new research has suggested that ROS act as a secondary signaling pathway for cells and play an important role in cellular infections. This warranted further study by observing how plants, specifically mosses, generate ROS in the presence of other cellular hormones such as salicylic acid (SA). This study focused on the effects of SA on the production of the ROS, specially hydrogen peroxide in ,model moss system of Physcomitrella patens. An experiment was designed to introduce a 2 µM solution of SA into the moss for a period of time ranging in time from 2 mins to 120 mins. To assay for hydrogen peroxide, potassium cyanide was introduced to prevent enzymes that were important in the breakdown of hydrogen peroxide. The moss samples were then ground up and a FOX assay was used to determine levels of hydrogen peroxide present in cell. It was determined that the most elevated levels of hydrogen peroxide were recorded after the moss had been exposed to SA for 20 minutes, which were more than double the levels of the control.