Kristin Buchner
Appalachian State University
Research and Creative Endeavors Day
April 23, 2009
 Organic hydrocarbon compounds
 Composed of isoprene units
 Secondary metabolites
 Emitted into the environment through leaching,
volatilization, or decomposition
 In nature:
 Attract/repel insects
 Deter other competitive plants
 In Industry: (“essential oils”)
 Flavor additives/enhancers
 Fragrances
 Alternative medicine
 Cleaning agents (pine-sol)
 Optimal Defense Theory
 Growth-Differentiation Balance hypothesis
Diagram taken from
Hamilton et al., 2001
 Old-Field Community Climate and Atmospheric
Manipulation (OCCAM)
 Solidago canadensis
 3 climate drivers:
 Elevated and ambient [CO2]
 Elevated and ambient temperature
 Ambient and low water supply
 How will terpene concentration be affected?
 48 samples were collected in
June 2008 from the OCCAM site
at ORNL in Oak Ridge, TN
 Gas Chromatography Analysis
 P-value ≤ 0.10
 24 samples collected from Dale
Cornett's Carolina Fraser Fir Farm in
Vilas, NC, on December 8, 2008
 Samples taken from damaged and
healthy areas of each Fir exhibiting
Balsam Twig Aphid damage
 P-value ≤0.05
Special thanks to the North Carolina Agricultural Extension for their support with this project.
tree
damage
tree x
damage
-pinene
0.2897
0.0075
0.2127
β-pinene
<0.0001
0.5692
0.1618
limonene
C1
C2
C3
C4
<0.0001
<0.0001
0.0003
<0.0001
0.0008
0.0135
0.031
0.1335
0.2338
0.0004
0.1404
0.8486
0.6021
0.0145
0.531
 Carbon allocation?
 Growth and repair vs. terpenes
 Improved defenses?
 Pre-emptive prevention or genetic resistance
 Overcompensation?
 Plants respond with a flood of defenses
 Plant tissue age?
 Older leaves could have lower defenses
 Langenheim, J.H.: 1994, 'Higher-Plant Terpenoids - a Phytocentric Overview of Their
Ecological Roles', Journal of Chemical Ecology 20, 1223-1280.
 Hamilton, J.G., Zangerl, A.R., DeLucia, E.H. and Berenbaum, M.R.: 2001, 'The
carbon-nutrient balance hypothesis: its rise and fall', Ecology Letters 4, 86-95.
 Sidebottom, J.: 2002, ‘Balsam Twig Aphid on Fraser Fir: CTN-019’, Extension
Forestry, North Carolina State University.
 Villalpando, S.N., Williams, R.S. and Norby, R.J.: 2009, 'Elevated air temperature
alters an old-field insect community in a multifactor climate change experiment',
Global Change Biology 15, 930-942.
 Williams, R.S., Thomas, R.B., Strain, B.R. and Lincoln, D.E.: 1997, 'Effects of elevated
CO2, soil nutrient levels, and foliage age on the performance of two generations of
Neodiprion lecontei (Hymenoptera : Diprionidae) feeding on loblolly pine',
Environmental Entomology 26, 1312-1322.