Exploring Species Boundaries for Neonectria magnoliae

Hannah Petronek*, Brian Lovett, Cameron M. Stauder, and Jeff Garnas

C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV 26506

Presentation Category: Agricultural & Environmental Sciences (Poster Presentation #63)

Student’s Major: Biochemistry

Fungi in the Nectriaceae include important plant pathogens that cause annual and perennial canker diseases. In the central Appalachian Mountains, a recent survey uncovered Neonectria magnoliae causing perennial cankers on Fraser magnolia (Magnolia fraseri) and tulip-poplar (Liriodendron tulipifera) but in different forests at different elevations. Phylogenetic data indicate N. magnoliae may include at least two cryptic species, but more data are needed to confirm these findings. To help further resolve species boundaries, additional isolates of N. magnoliae were collected from both hosts at three locations in West Virginia. Morphological studies revealed strains from one clade (from Fraser magnolia) produced both macro- and microconidia, while isolates from a second clade (from tulip-poplar) only produced microconidia. Phylogenetic analysis of elongation factor 1-alpha (EF1) DNA sequences confirmed our previous findings: isolates from each host fell within separate lineages and together formed a monophyletic clade. Recently, an additional strain of N. magnoliae was recovered from alder and was identical to strains from magnolia. Cross-pathogenicity studies are underway to determine pathogenicity of N. magnoliae strains from both lineages on tulip-polar. These findings highlight the importance of combining phylogenetic approaches with morphological studies and host range testing to better delimit species boundaries and understand the threats these species pose.

Funding:

Program/mechanism supporting research/creative efforts: a WVU 497-level course