First Report of Colletotrichum karstii Causing Anthracnose on Cigar Tobacco in Hainan, China

HomePlant DiseaseVol. 104, No. 7First Report of Colletotrichum karstii Causing Anthracnose on Cigar Tobacco in Hainan, China PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Colletotrichum karstii Causing Anthracnose on Cigar Tobacco in Hainan, ChinaQ. Zhao, C. J. Xia, J. Wang, H. K. Lv, J. Wang, J. G. Yang, X. Chen, Y. M. Qian, M. Li, and M. A. SohailQ. Zhaohttp://orcid.org/0000-0002-5340-7475Tobacco Research Institute, CAAS/Key Laboratory of Tobacco Pest Monitoring Controlling and Integrated Management, Qingdao 266101, China, C. J. XiaHaikou Cigar Research Institute, Hainan Provincial Branch of China National Tobacco Corporation, Haikou 570100, China, J. WangTobacco Research Institute, CAAS/Key Laboratory of Tobacco Pest Monitoring Controlling and Integrated Management, Qingdao 266101, China, H. K. LvHaikou Cigar Research Institute, Hainan Provincial Branch of China National Tobacco Corporation, Haikou 570100, China, J. Wang†Corresponding authors: J. Wang; E-mail Address: wangjing06@caas.cn and J. G. Yang; E-mail Address: yangjinguang@caas.cnTobacco Research Institute, CAAS/Key Laboratory of Tobacco Pest Monitoring Controlling and Integrated Management, Qingdao 266101, China, J. G. Yang†Corresponding authors: J. Wang; E-mail Address: wangjing06@caas.cn and J. G. Yang; E-mail Address: yangjinguang@caas.cnTobacco Research Institute, CAAS/Key Laboratory of Tobacco Pest Monitoring Controlling and Integrated Management, Qingdao 266101, China, X. ChenTobacco Research Institute, CAAS/Key Laboratory of Tobacco Pest Monitoring Controlling and Integrated Management, Qingdao 266101, China, Y. M. QianTobacco Research Institute, CAAS/Key Laboratory of Tobacco Pest Monitoring Controlling and Integrated Management, Qingdao 266101, China, M. LiZhengzhou University of Light Industry, Zhengzhou 450000, China, and M. A. SohailThe Key Lab of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan 430070, China AffiliationsAuthors and Affiliations Q. Zhao1 C. J. Xia2 J. Wang1 H. K. Lv2 J. Wang1 † J. G. Yang1 † X. Chen1 Y. M. Qian1 M. Li3 M. A. Sohail4 1Tobacco Research Institute, CAAS/Key Laboratory of Tobacco Pest Monitoring Controlling and Integrated Management, Qingdao 266101, China 2Haikou Cigar Research Institute, Hainan Provincial Branch of China National Tobacco Corporation, Haikou 570100, China 3Zhengzhou University of Light Industry, Zhengzhou 450000, China 4The Key Lab of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan 430070, China Published Online:14 May 2020https://doi.org/10.1094/PDIS-10-19-2191-PDNAboutSectionsSupplemental ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Cigar tobacco (Nicotiana tabacum L.) is an important cash crop in China. Due to suitable ecological conditions, Hainan province is a major area for growing cigar tobacco. Cigar tobacco leaves are both an important source of fiscal taxation and also the main source of income for farmers in Hainan province. In 2018 and 2019, necrotic leaf spots were observed on 5 to 15% of cigar tobacco plants in Danzhou city (109.58°E, 19.53°N) and Wuzhishan city (109.52°E, 18.78°N) in Hainan province, China. Lesions on plants in the fields were small, nearly round spots (0.2 to 0.5 cm in diameter) with light gray centers and narrow dark brown margins, and sometimes there were tiny black dots composed of sporophores scattered in the lesion center. To determine the causal agent, more than 10 symptomatic leaves from Danzhou city and Wuzhishan city were used for isolation. Small pieces of tissue were cut from lesion borders, sterilized with 2% sodium hypochlorite (NaClO) for 4 min and 70% ethanol for 30 s, rinsed with sterilized water (SW), and dried on a sterile tissue paper. Clean and excised tissue pieces were placed on potato dextrose agar plates and incubated at 28°C for 5 days in the dark. Pure colonies of the fungus had grayish white aerial mycelia and orange conidial masses in the centers, and sometimes there were tiny black dots composed of clusters of conidiophores and conidia scattered in the centers. A pure culture was deposited in the China General Microbiological Culture Collection Center (CGMCC, no. 3.19502). Microscopic observations showed single, straight to slightly curved, hyaline, cylindrical conidia that were 12.1 to 14.7 μm long and 6.4 to 8.2 μm wide. To confirm the identities of the isolate, the internal transcribed spacer (ITS) rDNA of the fungus was amplified using PCR and sequenced, as described by Yang et al. (2011). The sequencing results were then compared with other DNA sequences in the GenBank database by BLAST. Analysis of the PCR product (GenBank accession no. MK050853) showed that the sequence had 99.5% identity with the nucleotide sequences of Colletotrichum karstii (HM585409). Glyceraldehyde-3-phosphate dehydrogenase (GPDH, GDF1/GDR1) (Yang et al. 2011) was also sequenced and BLAST searched. The PCR product sequence had 99.8% identity with the nucleotide sequences of C. karstii (HM585391). Based on the morphological and molecular characteristics, the isolate CGMCC 3.19502 was identified as C. karstii. Pathogenicity tests were conducted by artificially inoculating 20 cigar tobacco plants (40 days old, cv. H211). A spore suspension (106 conidia/ml) was evenly sprayed on all leaves of the 20 plants. Ten control plants were treated similarly with SW. Twenty inoculated plants and 10 noninoculated plants were placed in a chamber maintained at 30°C and 90% relative humidity. After 7 days, the same symptoms observed from natural infections were on inoculated leaves, whereas the controls remained symptomless. This isolate also infected detached tobacco leaves. The pathogen was reisolated from inoculated leaves, and Koch's postulates were completed by confirming the identity of the isolated fungus based on the morphology and ITS sequence. Anthracnose caused by C. karstii was previously detected on Schefflera octophylla in Sichuan province (Li et al. 2017). To our knowledge, this is the first report of C. karstii causing anthracnose on cigar tobacco in China. Damage caused by C. karstii could cause significant economic losses if not managed. More research is needed to better understand this disease and establish control strategies.The author(s) declare no conflict of interest.References:Li, P. L., et al. 2017. Acta Phytopathol. Sin. 47:296. Google ScholarYang, Y. L., et al. 2011. Mycologie 32:229. Google ScholarThe author(s) declare no conflict of interest.Funding: Funding was provided by Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences (ASTIP-TRIC04) and Study on Occurrence Law and Control Technology of Cigar Pests and Diseases in Hainan (201846000024056).DetailsFiguresLiterature CitedRelated Vol. 104, No. 7 July 2020SubscribeISSN:0191-2917e-ISSN:1943-7692 DownloadCaptionA cucumber plant with a light gray lesion of charcoal rot at the soil line and microsclerotia visible on the stem (D. S. Egel et al.). Photo credit: D. S. Egel. Rot and discolored sepals of persimmon fruit caused by Mucor inaequisporus (S.-Y. Lee and H.-Y. Jung). Photo credit: H.-Y. Jung. Metrics Downloaded 664 times Article History Issue Date: 2 Jul 2020Published: 14 May 2020First Look: 19 Mar 2020Accepted: 14 Mar 2020 Pages: 2025-2025 Information© 2020 The American Phytopathological SocietyFundingScience and Technology Innovation Project of Chinese Academy of Agricultural SciencesGrant/Award Number: ASTIP-TRIC04Study on Occurrence Law and Control Technology of Cigar Pests and Diseases in HainanGrant/Award Number: 201846000024056Keywordsfungal diseasesleaf spot disease of cigar tobaccoColletotrichum karstiiThe author(s) declare no conflict of interest.Cited ByFirst Report of Colletotrichum cliviicola Causing Leaf Spot on Tobacco (Nicotiana tabacum) in Hunan Province of China16 July 2021 | Plant Disease, Vol. 73