Effects of the nematode Litylenchus crenatae subsp. mccannii and beech leaf disease on leaf fungal and bacterial communities on Fagus grandifolia (American beech).
Beech leaf disease (BLD) is a newly emerging disease in North America that affects American beech (Fagus grandifolia). This disease leads to disfigurement of the leaves, and is marked by characteristic dark, interveinal banding. It is increasingly recognized that the BLD is caused by a newly recognized nematode subspecies, Litylenchus crenatae subsp. mccannii. However, how nematode infestation of leaves affects the leaf microbiome, and whether changes in the microbiome could contribute to BLD symptoms and development is still uncertain. In this study, we examined bacterial and fungal communities associated with leaves of American beech both symptomatic and asymptomatic for BLD across nine sites in Ohio and Pennsylvania.