First Report of Anthracnose Caused by Colletotrichum liaoningense on Trichosanthes kirilowii in China

HomePlant DiseaseVol. 106, No. 2First Report of Anthracnose Caused by Colletotrichum liaoningense on Trichosanthes kirilowii in China PreviousNext DISEASE NOTE OPENOpen Access licenseFirst Report of Anthracnose Caused by Colletotrichum liaoningense on Trichosanthes kirilowii in ChinaL. X. Zhang, Y. F. Lin, L. Zhang, X. Wang, and J. H. SongL. X. Zhanghttps://orcid.org/0000-0002-2163-7655College of Plant Protection, Anhui Agricultural University, Hefei, 230036, China, Y. F. LinCollege of Plant Protection, Anhui Agricultural University, Hefei, 230036, China, L. Zhanghttps://orcid.org/0000-0002-2163-7655College of Plant Protection, Anhui Agricultural University, Hefei, 230036, China, X. WangCollege of Plant Protection, Anhui Agricultural University, Hefei, 230036, China, and J. H. Song†Corresponding author: J. H. Song; E-mail Address: jhsong@ahau.edu.cnCollege of Horticulture, Anhui Agricultural University, Hefei, 230036, China AffiliationsAuthors and Affiliations L. X. Zhang1 Y. F. Lin1 L. Zhang1 X. Wang1 J. H. Song2 † 1College of Plant Protection, Anhui Agricultural University, Hefei, 230036, China 2College of Horticulture, Anhui Agricultural University, Hefei, 230036, China Published Online:17 Jan 2022https://doi.org/10.1094/PDIS-07-21-1363-PDNAboutSectionsView articlePDFPDF PlusSupplemental ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat View articleTrichosanthes kirilowii Maxim (T. kirilowii) is widely grown in central China for its medicinal and edible value. In August 2020, an anthracnose-like disease was observed on fruit of T. kirilowii (cv. Wanlou9) in four fields (0.9 ha) located in Taihu county, Anhui Province of China. Approximately 60% of the T. kirilowii plants were affected in the fields. The symptoms initially consisted of small off-white necrotic spots, and later became larger, irregular gray necrotic lesions on green fruit, causing fruit rot and sometimes fruit drop. More than 10 symptomatic fruits were sampled, and small pieces of diseased tissue were surface sterilized in 0.1% HgCl2 for 2 min, 75% ethanol for 45 s, rinsed three times with sterile distilled water, then placed on potato dextrose agar (PDA) and incubated at 25°C in the dark. A fungus was consistently (80%) isolated from symptomatic fruit samples. Aerial mycelia were light gray and radially black with white in reverse medium. Conidia were rarely produced on PDA, but prolific on water agar. The conidia were cylindrical to clavate, both ends rounded, had an obvious circular granule in the center, and ranged from 14.6 to 19.9 μm × 5.4 to 7.3 μm. The morphological characteristics were similar to the descriptions of Colletotrichum liaoningense by Diao et al. (2017). For molecular identification, representative isolates LG5-4 and LG9-6 were selected. Genomic DNA was extracted, and the internal transcribed spacer (ITS) region, actin (ACT), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and β-tubulin (TUB2) genes were amplified by PCR (Duan et al. 2018; White et al. 1990) and sequenced bidirectionally. A BLAST search of GenBank revealed the ACT and TUB sequences had 95.83% (KP890097), 99.20%, 95.33% (KP890111), and 99.84% identity, respectively, to C. liaoningense CAUOS2. A phylogenetic analysis was conducted using MEGA7 based on concatenated sequences of the four genes, indicating that the isolates were closely clustered with reference strains of C. liaoningense (98% bootstrap value). The two strains were deposited in the China General Microbiological Culture Collection Center as CGMCC3.20344 and CGMCC3.20345, and their sequences deposited in GeneBank (accession nos. MW082811–12, MW117926–31, respectively). Pathogenicity tests were conducted on healthy fruit of T. kirilowii (cv. Wanlou9) using wound inoculation by pinpricking and droplet (106 conidia/ml) on fruit surface. The experiments were done with three fruit per isolate (LG5-4 and LG9-6) and replicated three times. The controls were inoculated with sterile water. The fruit were covered with plastic bags and kept in a chamber (>90% RH, 28 to 30°C) for 14 days. Typical symptoms of yellow-brown lesions appeared 14 days after inoculation. No symptoms were observed on the controls. The fungus was reisolated from the diseased tissues and identified as C. liaoningense by sequencing of the four genes, confirming Koch's postulates. C. liaoningense has been reported to cause anthracnose of mango and chili in China (Diao et al. 2017; Li et al. 2019). To our knowledge, this is the first report of C. liaoningense causing anthracnose on T. kirilowii. Due to cultivation of T. kirilowii in the region, further studies are required to develop management strategy of this disease.The author(s) declare no conflict of interest.References:Diao, Y. Z., et al. 2017. Persoonia 38:20. https://doi.org/10.3767/003158517X692788 Crossref, ISI, Google ScholarDuan, C. H., et al. 2018. Plant Dis. 102:2375. https://doi.org/10.1094/PDIS-03-18-0377-PDN Link, Google ScholarLi, Q. L., et al. 2019. Sci. Rep. 9:18891. https://doi.org/10.1038/s41598-019-54809-4 Crossref, ISI, Google ScholarWhite, T. J., et al. 1990. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA. Google ScholarFunding: Funding was provided by the Key Project of Science and Technology in Anhui Province of China (18030701211), the National Natural Science Foundation of China (32072378), and the Key Research and Development Projects in Anhui Province (202104b11020006).The author(s) declare no conflict of interest.DetailsFiguresLiterature CitedRelated Vol. 106, No. 2 February 2022SubscribeISSN:0191-2917e-ISSN:1943-7692 DownloadCaptionWater-soaked lesions on bougainvillea caused by Robbsia andropogonis (O. Morales-Galván et al.). Photo credit: L. F. Flores-López. Soybean leaf showing crinkling and downward curling, characteristic of infection by soybean mosaic virus (SMV) (S. van Bentum et al.). Photo credit: S. van Bentum. Metrics Downloaded 200 times Article History Issue Date: 28 Feb 2022Published: 17 Jan 2022First Look: 2 Sep 2021Accepted: 30 Aug 2021 Page: 765 Information© 2022 The American Phytopathological SocietyFundingKey Project of Science and Technology in Anhui Province of ChinaGrant/Award Number: 18030701211National Natural Science Foundation of ChinaGrant/Award Number: 32072378Key Research and Development Projects in Anhui ProvinceGrant/Award Number: 202104b11020006KeywordsColletotrichum liaoningenseidentificationphylogenetic analysisanthracnoseThe author(s) declare no conflict of interest.