Survey of Verticillium spp. occurring on Ailanthus in West Virginia as biological control agents

Rachel L. Gadd,* Brian R. Lovett, Hannah M. Petronek, and Matthew T. Kasson
Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV 26505

Presentation No.: 28

Assigned Category (Presentation Format): Agricultural & Environmental Sciences (Poster Presentations)

Student’s Major: Biochemistry

Tree-of-heaven (Ailanthus altissima) is a highly invasive tree species that threatens the natural biodiversity of the mid-Atlantic region and requires extensive management. A naturally occurring fungus, Verticillium nonalfalfae, has been found to effectively kill tree-of-heaven in OH, PA, and VA. A second Verticillium species, V.dahliae, has also been recovered but is less effective in controlling tree-of-heaven. Over the last decade, various strains of V.nonalfalfae have been used as biocontrols in these states. Given that West Virginia borders all three of these states, it’s possible that V.nonalfalfae is also present in WV. The main goal of this project was to scout for and isolate Verticillium spp. from symptomatic tree-of-heaven across WV in hopes of recovering the more virulent V. nonalfalfae to serve as a biocontrol in WV. Windshield surveys in the northern panhandle have uncovered several Verticillium infected Ailanthus stands. The isolates from these surveys were characterized morphologically by evaluating fungal resting structures and comparing them to known Verticillium strains. To date only V.dahliae has been recovered from these symptomatic stands but isolations are ongoing.

Funding: USDA APHIS

Program/mechanism supporting research/creative efforts: WVU's SURE program (Rita Rio & Michelle Richards-Babb)