Abstract Detail

Host/Plant Pathogen Interactions and Plant Health Management

Marr, Deborah L. [1], Jackson, Erin [2], Julian, Brandon [2], Kopey, Matthew [2], Wagar, Rob [2].

Endophytic fungal interactions in Alliaria petiolata (non-native garlic mustard) and species of Hydrophyllum (native waterleaf).

Previous studies have shown that secondary compounds in non-native Alliaria petiolata (garlic mustard) have a negative effect on mycorrhizal fungi. However, little is known about whether other endophytic fungi associated with native plants are affected by Alliaria petiolata. Fusarium and Trichoderma are endophytic fungi that are commonly present in three native species of Hydrophyllum in the Midwestern United States. First, we tested whether Fusarium isolated from each plant host (native Hydrophyllum appendiculatum and non-native Alliaria petiolata) can colonize roots of the other plant host. We found that Hydrophyllum appendiculatum was colonized by Fusarium strains isolated from garlic mustard within 72 hours. Garlic mustard roots were not colonized by Fusarium after 48 hours, but additional experiments are underway to determine if longer exposure is needed for root colonization to occur. Second, we tested whether allyl isothiocyanate (AITC), a secondary compound produced by Alliaria petiolata, affects fungal spore germination or mycelial growth of fungi isolated from either plant host. AITC significantly reduced spore germination in Trichoderma cultures isolated from garlic mustard, but had no significant effect on Fusarium spore germination. Fusarium mycelial growth was inhibited only at the highest concentrations of AITC (0.05 mM), and Trichoderma mycelial growth was only inhibited in fungal cultures isolated from Hydrophyllum virginianum. Third, we tested whether fungal competition occurs with or without the presence of plant roots. In the fungal competition experiments, Fusarium inhibited the growth of Trichoderma. In the root-fungal interaction experiments, Hydrophyllum roots inhibited the growth of Fusarium isolated from garlic mustard. However, garlic mustard roots did not inhibit the growth rate of either Trichoderma or Fusarium cultures isolated from either plant host. Overall, these results suggest that native Hydrophyllum species can be colonized by Fusarium species associated with garlic mustard, but that the roots of Hydrophyllum can inhibit some of the endophytic fungi associated with non-native garlic mustard.

1 - Indiana University South Bend, Department Of Biological Sciences, 1700 Mishawaka Avenue, South Bend, IN, 46634, USA
2 - Indiana University South Bend, Department of Biological Sciences, 1700 West Mishawaka Avenue, South Bend, IN, 46634, USA

Keywords:
Endophytic fungi
Plant-Pathogen Interaction
invasive species
Fusarium
Trichoderma
Alliaria petiolata
Hydrophyllum.

Presentation Type: Poster:Posters for Topics
Session: P
Location: Hall D/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 5:30 PM
Number: PPA031
Abstract ID:1006
Candidate for Awards:None