Date of Award
Invasive species pose a major threat to ecosystems worldwide. Therefore, understanding the traits that promote invasiveness is a key research focus for invasion biologists. The objective of this project was to assess light responses of invasive and non-invasive roses by using gas exchange measurements and to relate these responses to leaf nitrogen concentration. I compared the light response curves and leaf nitrogen concentrations of non-invasive and invasive roses, hypothesizing that increased photosynthetic rates and green leaf nitrogen concentrations are associated with invasiveness in these species. Using a greenhouse experiment, the plants were placed in a randomized block design and grown under controlled conditions. Light response curves were made with a LICOR 6400 infrared gas analyzer. Following gas exchange measurements, leaf nitrogen concentration was measured via micro-Dumas combustion on a CN analyzer. Contrary to expectations, there were no significant differences in photosynthetic light responses among invasive and non-invasive roses. However, the data suggest that invasive roses may use nitrogen more efficiently than non-invasive species. The goal of this study was to distinguish traits that allow invasive roses to outcompete non-invasive roses. Understanding the traits that facilitate the spread of invasive species can lead to interventions that may mitigate their negative effects on native environments.
D'Mello, Esther, "Light responses and leaf nitrogen of invasive and non-invasive Rosa sp." (2013). Senior Honors Projects. 14.