Spatial Analysis of Terpenes and Aphid Abundance in Solidago Altissima

ASU Author/Contributor (non-ASU co-authors, if there are any, appear on document)
Beatrice Smith (Creator)
Appalachian State University (ASU )
Web Site:
Ray Williams

Abstract: This study explores the connection between plant chemistry, plant herbivores, and the environment in which plants are grown. Understanding interspecific, community-level interactions is an essential part of understanding ecosystems as a whole. As native ranges shift with climate change, understanding which spatial and environmental factors may impact host plants and their associated herbivores is essential in order to best prepare for and manage these changes. Ramets from 5 Solidago altissima genotypes were collected, as part of a larger study, from five locations in Watauga County, North Carolina (USA) in 2013. Clonal replicates from each plant were grown in a greenhouse under common soil conditions, and Uroleucon nigrotuberculatum, a specialist aphid, was allowed to colonize the plants. Aphid abundance was recorded during the 2014 growing season (June - October). Leaf samples were taken from 3 individuals of each genotype and were tested using gas chromatography (GC) to find the amounts of volatile terpenes. Results were statistically analyzed using SAS version 9.3 and Excel 2010 to explore the relationships among genotype, terpene content, and aphid abundance. Spatial factors from the locations the plants were originally harvested included proximity to streams, land cover type, mean annual precipitation, elevation, and soil type. These data were compiled using ArcGIS 10.2 and were statistically analyzed using Excel 2010. A statistically significant relationship was found between plant genotype and aphid abundance (p=0.046), with aphids strongly preferring genotype number six. One terpene, ß- pinene, was found to vary significantly by genotype (p=0.03), but the others did not. Although results were not statistically significant, genotype 20 had the highest terpene content, and genotypes 3 had the lowest terpene content. Environmental factors of the location from which the original ramet was harvested were regressed against both terpene content and aphid abundance. These factors included precipitation, elevation, slope, land cover, hillshade, and proximity to nearest stream or water body. None of the environmental factors were found to significantly effect aphid colonization or terpene content. This research was part of a larger study in the laboratory of Ray Williams. This data joins a broad body of research on community genetics, community ecology, and plant-insect interactions. Information about population and community dynamics is crucial to the understanding of ecosystems, land management. Understanding how environmental attributes impact species and species interactions may help with predicting and mitigating the effects of climate change and range shifts of organisms.

Additional Information

Honors Project
Smith, B. (2015) Spatial Analysis of Terpenes and Aphid Abundance in Solidago Altissima. Appalachian State University, Boone, NC.
Language: English
Date: 2015

Email this document to