Min-Hye Jeong1,†, Eu Ddeum Choi2,†, Seol-Hwa Jang1, Sang-Min Kim3, and Sook-Young Park1,*
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/).
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.
Morphology, Phylogeny, Pyrenophora tritici-repentis, Triticum aestivum, Wheat