Korean Journal of Mycology (Kor. J. Mycol.)
Indexed in SCOPUS, KCI, DOAJ
OPEN ACCESS, PEER REVIEWED
pISSN 0253-651X
eISSN 2383-5249
RESEARCH ARTICLE

First Report of Pyrenophora tritici-repentis in Wheat (Triticum aestivum L.) in Korea and in vitro Selection of an Effective Fungicide

1Department of Plant Medicine, College of Life Science and Natural Resources, Sunchon National University, Suncheon 57922, Korea
2Pear Research Institute, National Institute of Horticultural & Herbal Science, Naju 58216, Korea
3Crop Foundation Research Division, National Institute of Crop Science, Rural Development Administration, Wanju 55365, Korea

*Correspondence to spark@scnu.ac.kr

These authors equally contributed.

Korean Journal of Mycology (Kor J Mycol) 2023 December, 51(4):277-286.
https://doi.org/10.4489/KJM.20230030
Received on August 16, 2023, Revised on November 06, 2023, Accepted on November 08, 2023, Published on December 31, 2023.
Copyright © The Korean Society of Mycology.
This is an Open Access article which is freely available under the Creative Commons Attribution-Non-Commercial 4.0 International License (CC BY-NC) (https://creativecommons.org/licenses/by-nc/4.0/).

ABSTRACT

Tan spot, caused by Pyrenophora tritici-repentis, is a major foliar disease in wheat worldwide. In April 2021, tan spot symptoms were observed in a commercial wheat field in Suncheon, Jeonnam Province, Korea, with over 5% of the wheat leaves exhibiting symptoms. These symptoms included oval-shaped tan necrosis surrounded by a bright halo. The three representative isolates exhibited irregular mycelial growth on V8-potato dextrose agar and produced pseudothecia. Based on the concatenated sequence datasets of four multi-genes, including the internal transcribed spacer, large subunit ribosomal RNA, glyceraldehyde3-phosphate dehydrogenase, and RNA polymerase II second-largest subunit genes, phylogenetic analysis revealed that these three isolates clustered in the same clade as P. tritici-repentis. Results of pathogenicity test indicated that the initial symptoms appeared 5 days post-inoculation (dpi), with typical tan spot symptoms developing at 7 dpi. The pathogen was successfully re-isolated from the symptomatic tissues, thus fulfilling Koch’s postulates. Furthermore, we selected three fungicides that effectively inhibited the mycelial growth of P. tritici-repentis by more than 90% in vitro. To the best of our knowledge, this is the first report of tan spot disease in wheat in Korea.

Keywords

Morphology, Phylogeny, Pyrenophora tritici-repentis, Triticum aestivum, Wheat

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