The Effects of Elevated CO2 Levels on Broad Bean, Vicia faba, Growth/Defense Tradeoffs

Name

Harley B. Kitching, Georgia Southern UniversityFollow

Publication Date

2017

Major

Biology (B.S.B.)

Document Type and Release Option

Thesis (open access)

Faculty Mentor

Edward B Mondor

Abstract

Atmospheric changes, associated with global climate change, are increasing at an unprecedented rate. Plants generally display higher rates of growth in response to elevated CO₂ levels, but this response varies among species. In addition, very little is known about how plant growth/defense tradeoffs will be altered by increasing CO₂ levels. By raising Broad bean, Vicia faba L., plants under ambient (400 ppm) and elevated (900 ppm) levels of CO₂, it was shown that atmospheric composition directly altered plant growth/defense tradeoffs. Plants grown under elevated CO₂ had lighter stem weights but greater numbers of extrafloral nectaries and higher rates of extrafloral nectar secretion. Thus, plants grown under elevated CO₂ invested more in defense (extrafloral nectaries and extrafloral nectar production) than growth (biomass). These results indicate that CO₂ may act as a stressor for Broad bean plants.

Recommended Citation

Kitching, Harley B., "The Effects of Elevated CO2 Levels on Broad Bean, Vicia faba, Growth/Defense Tradeoffs" (2017). Honors College Theses. 227.
https://digitalcommons.georgiasouthern.edu/honors-theses/227