Date of Graduation


Document Type


Degree Type



Davis College of Agriculture, Natural Resources and Design


Not Listed

Committee Chair

Matthew Kasson

Committee Co-Chair

Ember Morrissey

Committee Member

Ember Morrissey

Committee Member

Daniel Panaccione

Committee Member

Scott Salon

Committee Member

Donald Davis


Ailanthus altissima is a highly invasive exotic tree species entrenched throughout the United States. Since the discovery of a vascular wilt disease of Ailanthus in 2002, caused by the fungus Verticillium nonalfalfae, many studies are investigating its potential as a biocontrol focusing on efficacy, host specificity and disease transmission. This study addresses: the reproductive potential of Ailanthus; if V. dahliae alters Verticillium wilt progression; if hardiness zones influence the individual contributions of two Verticillium spp.; can a unique habitat affect biocontrol efficacy; and can the fungal proteome of V. nonalfalfae allow us to explain differences in host specificity? Cumulative seed production in individual Ailanthus reached ca. 10 and 52 million seeds over a 40-year and 100-year period, respectively. Forested sites inoculated with both Ailanthus pathogenic species of Verticillium experienced the same mortality rates as sites with just V. nonalfalfae alone. When comparing mortality caused by Verticillium wilt in three hardiness zones, it was found that there was no difference in disease progression. Ailanthus established on previous strip mine sites displayed resistance to the pathogen. Tree ring observations and X-ray fluorescence mineral assays indicated high concentrations of iron which inhibited Verticillium infection. Isolates of Verticillium species and strains from different plant hosts displayed differences in pathogenicity to Ailanthus seedlings and had distinct proteomes from each other when analyzed with MALDI-TOF-MS, indicating Verticillium isolates from different sources respond to their host environment differently.

Embargo Reason

Publication Pending