Get started
Work

First Report of Hyaloperonospora sp. Causing Downy Mildew of Stock (Matthiola incana) in Ohio

Year: 2024
Type: article
Abstract: Matthiola incana, commonly known as stock, is a flowering plant species in the Brassicaceae family, and is popularly used as a cut flower due to its fragrant, long-lasting blooms.In September 2023, stock 'Iron White' plants displaying symptoms and signs of downy mildew were observed within a high tunnel in a cut flower farm in Franklin Co., Ohio.Disease incidence was approximately 50%, covering an area of 140 m 2 .Water-soaked lesions, chlorosis, necrosis, and white sporulation on the abaxial side of the leaves were observed.Microscopic observation of diseased specimens (BPI 911250-51) revealed dichotomously branched sporangiophores with slender, curled tips bearing a single hyaline, ellipsoid to globose sporangium.The width of the sporangiophore trunks and ultimate branch lengths were on average 7.9 ± 1.2 µm (n = 4) and 12.9 ± 4.39 µm (n = 22), respectively.Sporangia measured on average 22.2 ± 2.4 µm × 19.6 ± 1.8 µm (n = 100).Morphological observations indicate that this species belongs to the genus Hyaloperonospora (Constantinescu and Fatehi 2002).PCR amplification and bidirectional sequencing of the rDNA ITS1-ITS2, LSU D1-D3, and mtDNA cox1 and cox2 regions were performed from DNA extracted from spores and mycelium.Using GenBank BLASTn, the ITS sequence had 822/823 and 830/832 base pairs matching to Hyaloperonospora parasitica from M. incana in Italy (MT275635; Bertetti et al. 2021) and M. sinuata in Spain (EU049268; Göker et al. 2009); cox1 and LSU had 649/681 and 755/764 base pairs matching to H. mayli, respectively (KC494943 and The author(s) declare no conflict of interest.
DOI: 10.1094/pdis-08-24-1708-pdn
Language: English
Subfield: Plant Science
Open Access status: bronze
OpenAlex ID: W4405897755
FWCI: 0.226
Cites: 4
Cited by: 1
Related to: 10