Student: Jennafer Hamlin
Faculty Mentor: Dr. Jennifer Rhode, Biology Department
Research Title: Site of Origin and Degree of
Plasticity Affect Success of an Invasive Liana, Celastrus
orbiculatus
Jenna was funded by SEEDS (Strategies for
Ecology Education, Diversity, and Sustainability;
http://www.esa.org/seeds/ ).
She presented her research at the (Ecological Society of
America) Conference in Albuquerque, New Mexico

Many factors affect plants’ invasibility, including features
of the novel community and of the plant itself. Exotic
plants with greater genetic diversity or phenotypic
plasticity are likely to be more successful invaders,
especially under shifting environmental conditions.
Celastrus orbiculatus (oriental bittersweet) is a liana
whose density has reached invasive proportions in western
North Carolina. Recent studies have tested bittersweet’s
physiological responses to a range of light conditions.
Using similar conditions to compare variation among both
light levels and genotypes, I examined site-specific
plasticity in this non-native liana. I predicted that
genotypes would respond differently to varying light
conditions and that some populations would be more plastic
than others. Shade cloth structures of varying light
conditions were used to simulate light levels below mature,
immature, or open tree canopies. Plants from three western
North Carolina sites (50 genotypes each) were cloned 8 times
to allow multiple clones to be exposed to different light
conditions. Clones were grown for 8 weeks with height, leaf
number, and leaf area measured after 0, 4, and 8 weeks. At
the experiments conclusion, dry mass of leaves, stems, and
roots was also assessed. My results showed different degrees
of plasticity and patterns of resource allocation among
populations. In addition, leaf response to light treatments
varied among populations. These traits could facilitate
increased invasiveness by oriental bittersweet, and a better
understanding of the relationship between genotype and
environment could be used to control this invasive’s spread.
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