Abstract

Fraxinus americana L. (white ash), a native North American tree commonly cultivated for its ornamental qualities, displayed symptoms of leaf spot disease in a sentinel garden located in Nanjing, Jiangsu, China, in 2022. This disease led to premature leaf shedding, adversely affecting the plant's growth and substantially diminishing its ornamental value. Potential fungal pathogens were isolated from the diseased leaves and the subsequent application of Koch's postulates confirmed the pathogenicity of the fungal isolates (BL-1, BL-2). Through a combination of multi-locus phylogenetic analysis, including ITS, ACT, ApMat, CAL, CHS-1, GAPDH, and TUB2, alongside morphological assessments, the fungus was conclusively identified as Colletotrichum jiangxiense. This represents the first record of C. jiangxiense affecting white ash, highlighting the important role of sentinel gardens in uncovering novel pathogen-plant host interactions.

Keywords

sentinel planting garden; Fraxinus americana L.; leaf spot; Colletotrichum jiangxiense; pathogenicity

Published in

Plants
2023, Volume: 12, number: 23, article number: 4001
Publisher: MDPI

SLU Authors

• Cleary, Michelle

  • Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Microbiology
Forest Science


Publication identifier

DOI: https://doi.org/10.3390/plants12234001

Permanent link to this page (URI)

https://res.slu.se/id/publ/127596