Allelopathy as an Invasive Mechanism for the Invasive Species Alliaria petiolata (Garlic Mustard)EPA Grant Number: F6F61509
Title: Allelopathy as an Invasive Mechanism for the Invasive Species Alliaria petiolata (Garlic Mustard)
Investigators: Barto, Eulondia Kathryn
Institution: Wright State University - Main Campus
EPA Project Officer: Zambrana, Jose
Project Period: September 1, 2006 through September 1, 2008
Project Amount: $111,172
RFA: GRO Fellowships for Graduate Environmental Study (2006) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Ecological Indicators/Assessment/Restoration , Fellowship - Terrestrial Systems Ecology
The goals of this project are to ascertain which compounds (glucosinolates, alliarinoside, and/or glycosylated flavonoids) produced by the invasive plant garlic mustard (Alliaria petiolata)are responsible for its allelopathic effects, to determine the field levels of these compounds over garlic mustard’s life cycle, to determine the half-lives of these compounds, and to determine at which stages in plant and mycorrhizal development they act.
I will use a variety of biochemical and microscopic techniques. I will use biomimetic extraction to determine field levels of allelopathic compounds by burying pieces of polydimethylsiloxane tubing and removing them at 3 month intervals to measure levels of absorbed compounds. Half-lives will be determined by spiking soil samples with known amounts of flavonoid compounds and then sampling through time until levels decrease by half. I will use epifluorescence microscopy to assess effects of allelopathic compounds on plant and mycorrhizal growth at various developmental stages (germination, pre-symbiosis growth, symbiosis formation, symbiosis growth). Pale touch-me-not (Impatiens pallida) plants will be grown in thin glass chambers to allow viewing of roots and mycorrhizae without destructive sampling. Light microscopy will be used as needed to visualize roots and epifluorescence microscopy will be used to view mycorrhizae, which fluoresce on exposure to blue light. These non-destructive monitoring techniques will allow me to observe intra- and extra-radical development of mycorrhizae through time, while simultaneously exposing various life stages to specific plant extracts. I will explore effects of a glucosinolate enriched fraction, a flavonoid glycoside enriched fraction, a total plant extract, and a live garlic mustard seedling.
This study will provide guidance for land managers trying to restore areas invaded by garlic mustard. If half-lives of allelopathic compounds are short, it will be possible to delay replanting of a site after garlic mustard removal until allelopathic compounds degrade. If half-lives are long, it may be necessary to add soil amendments such as activated carbon to adsorb allelopathic compounds, or to replant with life stages that are less susceptible to the allelopathic compounds.