1. Aphid Colonization of multiple species and genotypes of Solidago spp. Marae Lindquist Dr. Ray Williams Appalachian State University

2. Introduction Intraspecific genetic diversity in plants is important for associated insect communities Solidago species are known to exhibit large genetic variation, which may affect insect diversity and abundance Variation in individual genotypes (genetic identity) may affect phytochemistry important to insects Marae- put a few references you used in your paper here like the example below Crutsinger et al. 2006; Whitham et al. 2013

3. Objective This study tracked the abundance of a specialist aphid species on 3 different species of Solidago over several weeks and sampled leaves for key phytochemicals, including terpenes, N, and C:N ratio We hypothesized that differences in phytochemistry among species and genotypes would relate to aphid abundance

4. Terpenes Terpenes produced by plants are generally considered insect deterrents and vary among and within different plant species Terpenes can also be attractants for some co- evolved insect species, possibly on different genotypes of Solidago spp. Previous research in the Williams lab (Williams and Avakian 2015) has shown terpenes are important in aphid colonization of Solidago altissima http://upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Beta- pinen.png/130px-Beta-pinen.png http://www.pherobase.com/pherobase/gif/alpha-pinene.GIF

5. Three species of Solidago (4 genotypes per species) were individually potted and randomly arranged in a common garden design The native aphid Uroleucon nigrotuberculatum was allowed to naturally colonize the plants and abundance measured Leaf samples were taken for chemical analysis Methods Note: I put the images after this slide- seems more appropriate

6. Solidago juncea Early Goldenrod Solidago rugosa Wrinkleleaf Goldenrod Uroleucon nigrotuberculatum Red goldenrod aphid Solidago altissima Tall Goldenrod http://delawarewildflowers.org/i mages/solidago_canadensis_scab ra.jpg http://www.missouriplants.com/Yellowal t/Solidago_juncea_plant.jpg http://www.florafinder.com/LargePhotos/D5/S olidago_rugosa-90BAAB9065.jpg http://bugguide.net/images/cach e/OQM0FQX0S0FKYRLQVRYKWRK QDRFKDR3KBRZQNR701RMQDRI QJRQQNRQQR0U0DR7Q00P0R0M QTRIQH0U0FQ80BRX0FQ.jpg

7. SJ-7 SR-5 SJ-16 SA-11 SR-5 SJ-4 SR-3SR-9SA-20 SA-13 SJ-16 SA-11 SR-9SR-7 SA-11SA-6 SR-7 SJ-4SA-6SR-3 SJ-16 SJ-23 SA-20 SR-5SJ- 23 SR-7 SA-6 SA-13 SJ-23 SA-20SR-9 SR-3 SR-9 SJ-7 SJ-16 SA-13 SR-5 SJ-7 SA-20 SJ-23 SR-7 SR-3 SJ-4SA-11 SA-13 SA-6SJ-4 30cm Common Garden Design

9. Aphid abundance was measured every 3 days over a 5-week period Leaf samples were taken at the time of peak aphid abundance Leaves were used to analyze for N, C:N, and terpenes Plants were cut at bottom of stem and dried for total biomass A Gas Chromatography protocol developed by the Williams lab was used for the terpene analysis Data Collection

10. Aphid abundance was expressed as the number of aphids/g plant biomass We analyzed four previously identified terpenes: P- cymene, α-pinene, β-pinene, and Germacrene D Four unknown terpenes found in at least 80% of plants, C1, C2, C3, and C4, were also analyzed N and C:N ratio provided the nutritional quality of the plants

11. Statistics Methods Nested ANOVA tested for significant species and genotype effects S. altissima was also analyzed alone in order the compare our results to the Williams lab previous investigations. These data were analyzed using a General Linear Model. Linear regression used log transformed values Partial least square regression (PSLR) was used to relate multiple variables to aphid abundance

12. Results Total Aphid Abundance

13. P-Values- Nested ANOVA- Both Species SpeciesGenotype Ncontent0.1820.537 Aphid Abundance0.7990.163 α-pinene0.0730.205 β-pinene0.3670.003 p-cymene0.0390.445 C30.010.191 C40.3080.024 (p ≤ 0.05)

14. Nested ANOVA- S. altissima and S. juncea 1 2 3 4 56 7 8

15. P- values GLM- SA Only Species-SA Ncontent0.144 Aphid Abundance0.015 α-pinene0.049 β-pinene0.2 C30.005 C40.059 (p ≤ 0.05)

16. One-way Anova- S. altissima 56 7 8

17. Linear Regression- α - pinene P= 0.0196

18. PSLR- S. altissima and S. juncea

19. PSLR- S. altissima

20. Conclusions With S. altissima and S. juncea combined, there were no affects of species or genotype on aphid abundance Some terpenes were affected by genotype or species α-pinene was significantly related to aphid abundance with species combined PSLR found that terpenes, but not leaf nutrients, predicted aphid abundance for both species combined and for S. altissima alone Our hypothesis was partially supported

21. Acknowledgments Dr. Ray Williams Brian Bonville Julie Ragsdale Captain Jerry Meyer Dr. Mike Madritch http://www.homeoint.org/seror/patho1900/sol idago.gif

22. Questions?