|Averill, Kristine -|
|Whitlow, Thomas -|
|Ditommaso, Antonio -|
Submitted to: Weed Science Society of America Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: September 25, 2009
Publication Date: February 7, 2010
Citation: Averill, K.M., Whitlow, T.H., Milbrath, L.R., Ditommaso, A. 2010. Interspecific variability and phenotypic plasticity in photosynthesis for the invasive swallow-wort vines (Vincetoxicum spp.). Weed Science Society of America Meeting Abstracts, PB-42. https://srm.conference-services.net/reports/template/onetextabstract.xml?xsl=template/onetextabstract.xsl&conferenceID=1756&abstractID=344907 Technical Abstract: Vincetoxicum rossicum and V. nigrum are perennial invasive vines impacting several ecosystems in the northeastern United States and southeastern Canada, including old-fields and forest understories. The integrity of these ecosystems is threatened by these two Vincetoxicum species. In order to better define the niche requirements of these two troublesome invaders, we made photosynthesis measurements in July and September 2008 to determine the differences in photosynthetic ability between the two species and across habitats varying in light availability. We used a LI-COR 6400 gas exchange system. Photosynthetic rates for leaves of plants growing in a high light habitat (1500 µmol/m2/s photosynthetic photon flux density) were greater for V. nigrum [23 (1) µmol/m2/s] than for V. rossicum [18 (1) µmol/m2/s]. However, the species did not differ in the intermediate light environment of a forest edge (18-34 % of full sunlight). Although it remains unclear whether the invasive potential in this genus is species-specific, V. nigrum is clearly a sun-adapted species and shows potential for rapid growth in intermediate light environments. V. rossicum exhibited a high degree of plasticity in its photosynthetic ability with photosynthesis rates of 7.3 (0.5) µmol/m2/s in a forest understory, values that were higher than for co-occurring herbaceous species in this habitat. Both Vincetoxicum species exhibited higher photosynthesis rates than many early successional species in old-field habitats. Given that fecundity is highest in high light habitats, our results suggest that effective management of these species in old-fields should be a priority.