2025/01/01 by Fanny Iriarte, Héctor Urbina, Claudia A. Paez +3 · 1 voice
Biochemistry, Genetics and Molecular Biology · #Plant Pathogens and Fungal Diseases #Plant and Fungal Interactions Research #Plant biochemistry and biosynthesis
paper · doi:10.1094/php-02-25-0072-br
openalex publication_date 2025/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
In July 2024, several plants of cotton (cultivar Deltapine 2127 B3XF; Malvaceae, Rosids) were presenting symptoms of canker and dieback in experimental plots at the University of Florida, Institute of Food and Agricultural Sciences, North Florida Research and Education Center in Quincy, FL. Pycnidia found on canker lesions presented a large number of alpha (α) conidia and a small number of beta (β) conidia. Molecular identification was conducted by conventional PCR and sequencing of the internal transcribed spacer (ITS) (1,114 Kb, PQ422729), β-tubulin ( TUB2) (1,569 Kb, PQ435399), and translation elongation factor ( TEF1) (362 Kb, PQ435400) regions. BLAST analysis of ITS, TEF1, and TUB2 sequences resulted in >99% identity with GenBank accession numbers NR147543, KJ610881, and KJ590747, respectively. Sequences were obtained from the ex-type strain of ascomycetous fungus Diaporthe ueckeri (as ‘ euckerae’) CBS 139283 (Diaporthaceae, Sordariomycetes). Pathogenicity studies based on 20 pathogen inoculation sites and 10 plain agar inoculation sites resulted in similar canker symptoms where the same pathogen was recovered. Molecular identification of the pathogen confirmed D. ueckeri. To our knowledge, this is the first report of canker and dieback caused by D. ueckeri in cotton in Florida and in the United States.