Dissertations and Theses @ UNI
Availability
Open Access Thesis
Keywords
Fusarium diseases of plants; Plant-pathogen relationships--Genetic aspects; Academic theses;
Abstract
The filamentous fungus Fusarium verticillioides is plant pathogen that is responsible for billions of dollars in crop loss world wide. Fusarium verticillioides is of concern as it causes serious infections in maize and other agronomically important crop plants worldwide. Toxins produced by this fungus make grains from infected crops unusable. Plant resistance (or lack thereof) to disease is and has been for centuries a problem in agricultural productivity. Recent advances in the understanding of plant disease resistance promises to allow us to discover ways to counter the invasive properties of Fusarium verticillioides. Currently, very little is known about the virulence genes that make this fungus infective and what genes could make a plant resistant to it. To study possible resistance to Fusarium verticillioides native prairie plants were exposed to the fungus and observed for resistance. Tall dropseed showed promising results with approximately 11 % of plants being able to survive infection and was chosen as the organism of study for this research. Suppression subtractive hybridization was employed to isolate the genes involved in this apparent resistance. This experiment resulted in one gene sequence that was thought to be involved in the resistance. The isolated gene shares similarity with an uncharacterized gene involved in drought stress in poplar trees. There is also some similarity with an immune related gene from a clam worm that infects clams. In an effort to better understand the virulence of Fusarium verticillioides several mutant strains where created that had possible virulence genes deleted. PMK1 and TBL1 genes were selected for knockout because of their suspected involvement in virulence. The PMK1 knockout had an unusual morphology but its deletion could not be verified because of the fungi's multinucleate nature. TBLJ was also targeted for knockout but this knockout is suspected to be non-viable since no transformed colonies were successfully recovered. While these studies begin to help us understand the complex virulence of and plant resistance to Fusarium verticillioides there are many issues that need to be resolved. Isolating and understanding genes that could confer resistance to crop plants will lead to increased productivity in new resistance cultivars.
Year of Submission
2009
Degree Name
Master of Science
Department
Department of Biology
First Advisor
James Jurgenson
Second Advisor
Tihuan Abebe
Third Advisor
Nalin Goonesekere
Date Original
2009
Object Description
1 PDF file (101 leaves)
Copyright
©2009 Tracy Lynn Bruns
Language
en
File Format
application/pdf
Recommended Citation
Bruns, Tracy Lynn, "Resistance to and Virulence of Fusarium verticillioides" (2009). Dissertations and Theses @ UNI. 2213.
https://scholarworks.uni.edu/etd/2213
Comments
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