|WIESE, COSIMA - Misericordia University|
Submitted to: American Society of Plant Biologists Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/2010
Publication Date: 8/1/2010
Citation: Wiese, C., Burkey, K.O. 2010. Soluble leaf apoplastic constituents of O3-sensitive and tolerant soybeans and snap beans. American Society of Plant Biologists Annual Meeting. Abstract P07077.
Technical Abstract: Upon entry into leaves, ozone (O3) and reactive oxygen species (ROS) derived from O3 must pass through the leaf apoplast and cell wall before reacting with the plasma membrane to initiate plant responses. The leaf apoplast, therefore, represents a first line of defense in detoxifying ROS and preventing oxidative damage. This project was carried out to determine whether there are apoplastic compounds other than ascorbic acid that have antioxidant capacity and, therefore, may play a role in mediating plant response to O3. The objectives of this study are to investigate whether there are differences in the apoplastic constituents of two genotypes each of soybean and snap bean which differ in their O3 tolerance, and whether exposure to O3 affects the quantity and types of apoplastic constituents in these genotypes. Snap bean and soybean plants were exposed to charcoal-filtered (CF) air or elevated O3. Leaf intercellular wash fluid (IWF) was recovered and analyzed by reversed-phase HPLC using a column selected for separation of highly polar aromatic compounds. Snap bean and soybean plants contained unique profiles of soluble compounds in the leaf apoplast demonstrating significant species differences. In snap bean, no major genotype or O3 treatment effects were observed. In soybean, significant differences in quantities of apoplast constituents were observed when the two genotypes were compared, often with greater amounts present in O3-tolerant Fiskeby than in the O3-sensitive Mandarin Ottawa, regardless of treatment. Several peaks present in both soybean genotypes were reduced by O3 treatment in Mandarin Ottawa but not in Fiskeby. Future work will be directed toward identification of the major apoplast constituents and their role, if any, in O3 tolerance.