Leaf Spot Caused by Didymella segeticola on Tobacco in China

HomePlant DiseaseVol. 104, No. 5Leaf Spot Caused by Didymella segeticola on Tobacco in China PreviousNext DISEASE NOTES OPENOpen Access licenseLeaf Spot Caused by Didymella segeticola on Tobacco in ChinaZhenni Guo, Honglian Xie, Hancheng Wang, Yu Huang, QianLi Chen, Ligang Xiang, Zhihe Yu, and Xuehui YangZhenni GuoCollege of Life Science, Yangtze University, Jingzhou 434025, Hubei, P.R. ChinaKey Laboratory of Molecular Genetics, Guizhou Academy of Tobacco Science, Guiyang 550081, Guizhou, P.R. China, Honglian XieCollege of Agriculture, Yangtze University, Jingzhou 434025, Hubei, China, Hancheng Wang†Corresponding authors: H. Wang; E-mail Address: xiaobaiyang126@hotmail.com and Z. Yu; E-mail Address: zhiheyu@hotmail.com and X. Yang; E-mail Address: 514295432@qq.comhttp://orcid.org/0000-0001-7423-7121Key Laboratory of Molecular Genetics, Guizhou Academy of Tobacco Science, Guiyang 550081, Guizhou, P.R. China, Yu HuangCollege of Agriculture, Guizhou University, Guiyang 550025, Guizhou, P.R. China, QianLi ChenCollege of Agriculture, Guizhou University, Guiyang 550025, Guizhou, P.R. China, Ligang XiangCollege of Life Science, Yangtze University, Jingzhou 434025, Hubei, P.R. ChinaKey Laboratory of Molecular Genetics, Guizhou Academy of Tobacco Science, Guiyang 550081, Guizhou, P.R. China, Zhihe Yu†Corresponding authors: H. Wang; E-mail Address: xiaobaiyang126@hotmail.com and Z. Yu; E-mail Address: zhiheyu@hotmail.com and X. Yang; E-mail Address: 514295432@qq.comCollege of Life Science, Yangtze University, Jingzhou 434025, Hubei, P.R. China, and Xuehui Yang†Corresponding authors: H. Wang; E-mail Address: xiaobaiyang126@hotmail.com and Z. Yu; E-mail Address: zhiheyu@hotmail.com and X. Yang; E-mail Address: 514295432@qq.comGuizhou Institute of Plant Protection, Guizhou Academy of Agricultural Sciences, Guiyang 550006, P.R. China AffiliationsAuthors and Affiliations Zhenni Guo1 2 Honglian Xie3 Hancheng Wang2 † Yu Huang4 QianLi Chen4 Ligang Xiang1 2 Zhihe Yu1 † Xuehui Yang5 † 1College of Life Science, Yangtze University, Jingzhou 434025, Hubei, P.R. China 2Key Laboratory of Molecular Genetics, Guizhou Academy of Tobacco Science, Guiyang 550081, Guizhou, P.R. China 3College of Agriculture, Yangtze University, Jingzhou 434025, Hubei, China 4College of Agriculture, Guizhou University, Guiyang 550025, Guizhou, P.R. China 5Guizhou Institute of Plant Protection, Guizhou Academy of Agricultural Sciences, Guiyang 550006, P.R. China Published Online:20 Feb 2020https://doi.org/10.1094/PDIS-11-19-2398-PDNAboutSectionsSupplemental ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Tobacco (Nicotiana tabacum L.) is a leafy, annual, solanaceous plant grown commercially for its leaves. In China, the seed area of tobacco was over 14,000 km2, and the yield of tobacco leafage increased to 31.32 million tons in 2011 (Meng et al. 2015). In August 2019, diseased leaves of tobacco that had sandy beige with dark-brown edge, circular, elliptical or irregular shaped lesions and surrounded by yellow halos were obtained (cv. Yunyan 87) in Shibing (27.03° N, 108.11° E), Guizhou, China. Diseased leaf segments were surface sterilized and plated on potato dextrose agar (PDA). Isolate YBZ121 was selected for identification. The colonies had dense aerial hyphae, initially white and later producing gray near the center when cultured on PDA. The colonies had woolly aerial hyphae, white to gray eventually, and produced pycnidia on oatmeal agar (Boerema et al. 2004). Pycnidia were dark, spherical or flat spherical, and 80.3 to 148.4 µm in diameter. Conidia were oval mostly, smooth, aseptate, usually guttulate, and the size was 3.8 to 4.9 × 1.9 to 2.7 µm. The rDNA internal transcribed spacer region (ITS) with primers ITS1f/ITS4 (Gardes and Bruns 1993; White et al. 1990), 28S ribosomal RNA gene (LSU) with primers LROR/LR7 (Rehner and Samuels 1994), beta-tubulin gene (TUB2) with primers Btub2Fd/Btub4Rd (Woudenberg et al. 2009), and RNA polymerase II second largest subunit gene (RPB2) with primers RPB2-5F2/fRPB2-7cR (Liu et al. 1999) of YBZ121 were sequenced (GenBank accession nos. MN639735, MN639771, MN640785, and MN640786, respectively). A phylogenetic tree based on these four concatenated sequences showed that YBZ121 comprised a clade with Didymella segeticola (syn. Phoma segeticola) strain CGMCC 3.17489 with 98% bootstrap support. Tobacco plants at seedling stage (six to seven leaves) without visible disease were used for the pathogenicity test. Sterile filter papers (5 mm in diameter) were immersed in conidial suspension (106 spores/ml) containing 0.01% Tween 80 for 1 min and then placed on leaves of tobacco plants, with sterile water containing 0.01% Tween 80 used as a noninoculated control. One leaf of tobacco plant was inoculated with four pieces of filter paper containing spores and one inoculated with no spores, with three replicates per treatment, and then put in a plant incubator at 28°C with a 12/12 h light/dark cycle. Nine days after incubation, typical symptoms were observed on inoculated leaves but not on control leaves. Koch's postulates were fulfilled by reisolation of D. segeticola from diseased leaves. Based on morphological and multigene molecular data, isolate YBZ121 was identified as D. segeticola Q. Chen, sp. nov. described as a new taxon by Chen et al. (2015). It has been reported to cause leaf spot on tea in China (Zhao et al. 2018). However, to our best knowledge, this is the first report of D. segeticola causing leaf spot on tobacco in China. D. segeticola has the potential to cause considerable economic loss to farmers. Disease management of leaf spot caused by D. segeticola on tobacco needs to be developed to reduce losses in the future.The author(s) declare no conflict of interest.References:Boerema, G. H., et al. 2004. Phoma Identification Manual. CABI Publishing, Wallingford, U.K. Google ScholarChen, Q., et al. 2015. Phytotaxa 197:267. https://doi.org/10.11646/phytotaxa.197.4.4 Crossref, ISI, Google ScholarGardes, M., and Bruns, T. D. 1993. Mol. Ecol. 2:113. https://doi.org/10.1111/j.1365-294X.1993.tb00005.x Crossref, ISI, Google ScholarLiu, Y. J., et al. 1999. Mol. Biol. Evol. 16:1799. https://doi.org/10.1093/oxfordjournals.molbev.a026092 Crossref, ISI, Google ScholarMeng, A., et al. 2015. J. Energy Inst. 88:480. https://doi.org/10.1016/j.joei.2014.10.003 Crossref, ISI, Google ScholarRehner, S. 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Google ScholarThe author(s) declare no conflict of interest.Funding: Funding was provided by National Natural Science Foundation of China (31960550), Guizhou Excellent Young Talent Platform ([2017]5619), Guizhou Science and Technology Project ([2018]2356), China National Tobacco Corporation (110202001035(LS-04)), and Guizhou Tobacco Company (201714, 201914).DetailsFiguresLiterature CitedRelated Vol. 104, No. 5 May 2020SubscribeISSN:0191-2917e-ISSN:1943-7692 DownloadCaptionSymptoms observed in the field on zucchini plants caused by Fusarium solani f. sp. cucurbitae (A. Pérez-Hernández et al.). Photo credit: J. M. Gómez-Vázquez. Peach tree with excavated root collar (S. B. Miller et al.). Photo credit: G. Schnabel. Metrics Downloaded 1,291 times Article History Issue Date: 3 May 2020Published: 20 Feb 2020First Look: 20 Dec 2019Accepted: 17 Dec 2019 Page: 1559 Information© 2020 The American Phytopathological SocietyFundingNational Natural Science Foundation of ChinaGrant/Award Number: 31960550Guizhou Excellent Young Talent PlatformGrant/Award Number: [2017]5619Guizhou Science and Technology ProjectGrant/Award Number: [2018]2356China National Tobacco CorporationGrant/Award Number: 110202001035(LS-04)Guizhou Tobacco CompanyGrant/Award Number: 201714Grant/Award Number: 201914KeywordsDidymella segeticolaleaf spottobaccoThe author(s) declare no conflict of interest.Cited ByLeaf Spot Caused by Epicoccum latusicollum on Tobacco in ChinaZhenni Guo, Zhihe Yu, Hancheng Wang, Honglian Xie, and Tingting Liu8 December 2020 | Plant Disease, Vol. 105, No. 2Fungal Composition and Diversity of the Tobacco Leaf Phyllosphere During Curing of Leaves4 September 2020 | Frontiers in Microbiology, Vol. 11