Wednesday, August 5, 2009 - 8:40 AM

COS 62-3: Population differences in the ability of Oxalis acetosella L. to respond to environmental changes

Jack T. Tessier, SUNY Delhi

Background/Question/Methods

The ability of plant species to respond to changes in their environment brought on by climate change will depend on their genetic variation and phenotypic plasticity within and among populations. To assess the ability of Oxalis acetosella L. to respond to changes in its environment, I conducted a reciprocal transplant study between two populations that had previously displayed temporal differences in leaf longevity and patterns of leaf production and senescence. The population in Algonquin State Forest, CT, USA grows under evergreen and deciduous canopies, and the population from the Catskill Mountains, NY, USA grows under a deciduous canopy. Plants from the Catskills were collected in the fall of 2006 and planted adjacent to populations under both evergreen and deciduous canopies in Algonquin, and plants from both the evergreen and deciduous canopy areas of Algonquin were collected in the fall of 2007 and planted adjacent to populations in the Catskills. Individual leaves of all plants were monitored from the time of planting until the following fall.

Results/Conclusions

In Algonquin, native plants under the evergreen canopy had the longest leaf longevity and transplanted Catskill plants had the shortest leaf longevity.  Significant differences between native Algonquin and transplanted Catskill plants existed in the timing of relative leaf production and loss, relative change in leaf number, and relative leaf turnover. In the Catskills, leaf longevity and measures of leaf turnover of transplanted Algonquin plants did not differ significantly from those of native Catskill plants. Plants from the Algonquin site therefore exhibited a greater ability to alter their leaf habit to match that of local conditions than did plants from the Catskill site. The extent of the genetic differences between the two populations remains to be determined. These results suggest that there will be population-specific differences in the ability of plant species to respond to ecosystem changes brought on by climate change.