Date of Award


Degree Type


Degree Name

Honors Thesis



First Advisor

Nathanael Hauck


The moss species Physcomitrella patens and Amblystegium serpens were used to categorize the effects of the phytohormone ethylene in the plant-pathogen response mechanism systemic acquired resistance (SAR) in non-vascular plants. The results outlined in this thesis found that individual exposure to the ethylene precursor molecules ACC and ethephon both up-regulated ethylene responsive genes in P. patens, demonstrating a positive response to ethylene exposure in the moss. Exposure to ACC and ethephon in A. serpens followed by inoculation with the fungal pathogen Pythium irregulare demonstrated an ambiguous resistance response induced by ethylene exposure in the moss. The growth rate of P. irregulare on BCD media when exposed to concentrations of ACC and ethephon was also measured, to determine any inhibitory effects of the ethylene precursor molecules on fungal pathogen growth.