Aaron Cantor, Alison Hale, Justin Aaron , M . Brian Traw, Susan Kalisz By: Megan Kittleson

1. Low allelochemical concentrations detected in garlic mustard-invaded forest soils inhibit fungal growth and AMF spore germination AaronCantor, Alison Hale, Justin Aaron, M. Brian Traw, Susan Kalisz By: Megan Kittleson

2. General Background • Garlic Mustard (AlliariaPetiolata) • Cool season biennial herb • Commonly found in moist, shaded soils • Native to Europe; introduced in 1800’s • Invasive species • Found to have antimicrobial effects

4. Experiment Specific Background • Inhibitory effects due to allelochemicals • Secondary compounds included cyanide, flavonoids, glucosinolates, and gyclosides • Concentrations of AITC in soil have been unknown • Highly potent anti-fungal properties • Many native plants rely on arbuscularmycorrhizal fungi (AMF) BITC Glucosinolates AITC (allylisothiocyanate)

5. Goals of the Experiment • Determine timing of release and natural concentrations of AITC • Quantify the impact of garlic mustard on fungal abundance • Determine the range of AITC concentrations that can suppress AMF spore germination

6. Methods • Two sites tested; established paired plots • Garlic mustard invaded • Garlic mustard absent (control) • Determined lowest level of AITC present in soil • Approx: 0.001 mM • Tested Glomusclarumspores against varied concentrations of AITC

7. Methods • Two trials of bioassay conducted • 2009 – 4 petri dishes per concentration • 2010 – 5 petri dishes per concentration • Spores washed twice in 2.5% chloramine-T salt hydride • 16-26 spores pipetted in each Petri dishes • Contained water-agarosemedia • AITC solutions of varied concentrations created • Commercial AITC and deionized water • Sterile deionized water was negative control • 6 ml of respective treatment pipetted to lid of inverted petri dish

8. Methods • Sealed all petri dishes twice with Parafilm • Placed in a 2% CO2 incubator at 28˚ C in the dark for 1 week • After 1 week collected data on spore germination using a dissecting scope • One-way ANOVA and pairwise comparisons in SAS

9. Results

10. Results • All concentrations of AITC significantly inhibited germination • 2009 trial • ANOVA: p < 0.0001 • Pairwise comparison : all p < 0.0001 compared to control • 2010 trial • ANOVA: p < 0.0026 • Pairwise comparison: all p < 0.01 • Percentage of G. clarumspores that germinated decreased as AITC increased • Lowest detected level of AITC caused 57% germination failure

11. My Research • Does garlic mustard plant tissue show similar inhibitory effects on bacteria? • Are there any variations between first and second year plants?

12. Questions?

13. Bibliography • Aaron, Cantor, Alison Hale, Justin Aaron, M. Brian Traw, and Susan Kalisz. "Low Allelochemical Concentrations Detected in Garlic Mustard- invaded Forest Soils Inhibit Fungal Growth and AMF Spore Germination."Academic Search Complete. EBSCO, 15 Nov. 2010. Web. 9 Oct. 2012. • "Garlic Mustard." Invasive Plant Atlas of the United States. The University of Georgia - Center for Invasive Species and Ecosystem Health, 8 Sept. 2011. Web. 26 Nov. 2012. <http://www.invasiveplantatlas.org/>. • "Plants - Garlic Mustard (AlliariaPetiolata)." National Invasive Species Information Center. USDA National Agriculture Library, 12 Aug. 2012. Web. 25 Nov. 2012. <http://www.invasivespeciesinfo.gov>. • Stinson, Kristina. "Garlic Mustard Suppression of Mutualistic Fungi Stronger in North America Than Europe." Harvard Forest. Harvard University, 1 Apr. 2008. Web. 26 Nov. 2012. <http://harvardforest.fas.harvard.edu/>. • "Weed of the Week: Garlic Mustard." Forest Health Protection. USDA Forest Service, 1 Aug. 2005. Web. 25 Nov. 2012. <http://na.fs.fed.us>.