First Report of Root Rot Caused by Ilyonectria robusta in the Medicinal Herb Aconitum carmichaelii in China

HomePlant DiseaseVol. 107, No. 10First Report of Root Rot Caused by Ilyonectria robusta in the Medicinal Herb Aconitum carmichaelii in China PreviousNext DISEASE NOTE OPENOpen Access licenseFirst Report of Root Rot Caused by Ilyonectria robusta in the Medicinal Herb Aconitum carmichaelii in ChinaHongsu Wang, Yanxi Zhu, Bo Lu, Weijing He, Juan Lin, Yuxia Yang, Songlin Zhang, Bing Luo, Xin Zhang, Qingmao Fang, Mei Zhang, and Yanli XiaHongsu Wanghttps://orcid.org/0000-0002-5400-1020Sichuan Academy of Traditional Chinese Medicine Sciences, Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica, Chengdu, Sichuan 610041, ChinaSearch for more papers by this author, Yanxi ZhuChengdu University, Chengdu, Sichuan 610106, ChinaSearch for more papers by this author, Bo LuMaize Research Institute of Sichuan Agricultural University, Chengdu, Sichuan 611130, ChinaSearch for more papers by this author, Weijing HeSichuan Academy of Traditional Chinese Medicine Sciences, Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica, Chengdu, Sichuan 610041, ChinaSearch for more papers by this author, Juan LinSichuan Academy of Traditional Chinese Medicine Sciences, Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica, Chengdu, Sichuan 610041, ChinaSearch for more papers by this author, Yuxia YangSichuan Academy of Traditional Chinese Medicine Sciences, Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica, Chengdu, Sichuan 610041, ChinaSearch for more papers by this author, Songlin ZhangSichuan Academy of Traditional Chinese Medicine Sciences, Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica, Chengdu, Sichuan 610041, ChinaSearch for more papers by this author, Bing LuoSichuan Academy of Traditional Chinese Medicine Sciences, Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica, Chengdu, Sichuan 610041, ChinaSearch for more papers by this author, Xin ZhangSichuan Development Service Center for Traditional Chinese Medicine, Chengdu, ChinaSearch for more papers by this author, Qingmao FangSichuan Academy of Traditional Chinese Medicine Sciences, Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica, Chengdu, Sichuan 610041, ChinaSearch for more papers by this author, Mei Zhang†Corresponding authors: M. Zhang; E-mail Address: [email protected], and Y. L. Xia; E-mail Address: [email protected]https://orcid.org/0009-0000-6085-5578Sichuan Academy of Traditional Chinese Medicine Sciences, Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica, Chengdu, Sichuan 610041, ChinaSearch for more papers by this author, and Yanli Xia†Corresponding authors: M. Zhang; E-mail Address: [email protected], and Y. L. Xia; E-mail Address: [email protected]https://orcid.org/0000-0002-6748-4535Chengdu University, Chengdu, Sichuan 610106, ChinaSearch for more papers by this authorAffiliationsAuthors and Affiliations Hongsu Wang1 Yanxi Zhu2 Bo Lu3 Weijing He1 Juan Lin1 Yuxia Yang1 Songlin Zhang1 Bing Luo1 Xin Zhang4 Qingmao Fang1 Mei Zhang1 † Yanli Xia2 † 1Sichuan Academy of Traditional Chinese Medicine Sciences, Sichuan Provincial Key Laboratory of Quality and Innovation Research of Chinese Materia Medica, Chengdu, Sichuan 610041, China 2Chengdu University, Chengdu, Sichuan 610106, China 3Maize Research Institute of Sichuan Agricultural University, Chengdu, Sichuan 611130, China 4Sichuan Development Service Center for Traditional Chinese Medicine, Chengdu, China Published Online:28 Sep 2023https://doi.org/10.1094/PDIS-08-22-1799-PDNAboutSectionsView articlePDFSupplemental ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat View articleAconitum carmichaelii Debeaux is used as a traditional Chinese medicine because of its antiarrhythmic, anti-inflammatory, and other pharmacological functions. It is widely cultivated in China. According to our survey, about 60% of A. carmichaelii in Qingchuan, Sichuan, suffered from root rot, reducing yields by 30% in the past 5 years. Symptomatic plants exhibited stunted growth, dark brown roots, reduced root biomass, and fewer root hairs. The disease caused root rot and plant death in 50% of the infected plants. In October 2019, 10 symptomatic 6-month-old plants were collected from fields in Qingchuan. Diseased pieces of the roots were surface sterilized with sodium hypochlorite solution (2%), rinsed three times in sterile water, plated on potato dextrose agar (PDA), and incubated at 25°C in the dark. Six single-spore isolates of a Cylindrocarpon-like anamorph were obtained. After 7 days, the colonies on PDA were 35 to 37 mm in diameter with regular margins. The plates were covered with felty aerial mycelium, white and buff, and the reverse side was chestnut near the center with an ochre-to-yellowish leading edge. On Spezieller Nährstoffarmer agar (SNA), macroconidia were one to three septate, straight or slightly curved, cylindrical, with rounded ends, and varied in size: one septate measuring 15.1 to 33.5 × 3.7 to 7.3 μm (n = 250), two septate with 16.5 to 48.5 × 3.7 to 7.6 μm (n = 85), and three septate with 22.0 to 50.6 × 4.9 to 7.4 μm (n = 115). Microconidia were ellipsoid to ovoid and zero to one septate; aseptate spores were 4.5 to 16.8 × 1.6 to 4.9 μm (n = 200), and one-septate spores were 7.4 to 20.0 × 2.4 to 5.1 μm (n = 200). Chlamydospores were brown, thick walled, globose to subglobose, and 7.9 to 15.9 μm (n = 50). The morphology of these isolates was consistent with the previous description of Ilyonectria robusta (Cabral et al. 2012). The isolate QW1901 was characterized by sequencing the ITS, TUB, H3, and tef1α loci using previously reported primer pairs: ITS1/ITS4 (White et al. 1990), T1/Bt-2b (O’Donnell and Cigelnik 1997), CYLH3F/CYLH3R (Crous et al. 2004), and EF1/EF2 (O’Donnell et al. 1998), respectively. A BLASTn search of the sequences of ITS, TUB, H3, and tef1α showed that QW1901 shared 99.26, 97.89, 97.79, and 99.17% identity, respectively, with the ex-type strain of I. robusta (CBS308.35). The ITS, TUB, H3, and tef1α sequences were deposited in GenBank under accession numbers MW534715 and MW880180 to MW880182, respectively. A phylogenetic tree was constructed from a neighbor-joining analysis on the alignment of the combined ITS, TUB, H3, and tef1α sequence. QW1901 clustered with the ex-type strain of I. robusta. To confirm the pathogenicity of I. robusta, bare roots of healthy 6-month-old A. carmichaelii plants were inoculated with mycelial plugs of 7-day-old QW1901 colonies selected randomly (Lu et al. 2015). Five needle-wounded lateral roots and five intact roots were inoculated as replicates with pathogen-free agar plugs as controls. Then, all plants were grown in sterile soil in a growth chamber at 20 ± 1°C and watered regularly. Pathogenicity assays were repeated twice. After 20 days of cultivation, infected plants exhibited symptoms similar to those observed in the field. All control plants remained asymptomatic. Sequencing confirmed the reisolation of I. robusta from the inoculated plants, satisfying Koch’s postulates. I. robusta has been reported to cause root rot of plants such as Codonopsis tangshen and Panax ginseng (Lu et al. 2015; Zheng et al. 2022) and has also been reported to be isolated from A. kongboense in China (Wang et al. 2015). However, this is the first report of the pathogen causing root rot of A. carmichaelii. Management measures, such as growing disease-free seedlings in sterile soil, should be adopted to minimize the risk of this pathogen.The author(s) declare no conflict of interest.References:Cabral, A., et al. 2012. Mycol. Prog. 11:655. https://doi.org/10.1007/s11557-011-0777-7 Crossref, ISI, Google ScholarCrous, P. W., et al. 2004. Stud. Mycol. 50:415. Google ScholarLu, X. H., et al. 2015. Plant Dis. 99:156. https://doi.org/10.1094/PDIS-06-14-0663-PDN Link, ISI, Google ScholarO’Donnell, K., and Cigelnik, E. 1997. Mol. Phylogenet. Evol. 7:103. https://doi.org/10.1006/mpev.1996.0376 Crossref, ISI, Google ScholarO’Donnell, K., et al. 1998. Proc. Natl. Acad. Sci. U.S.A. 95:2044. https://doi.org/10.1073/pnas.95.5.2044 Crossref, ISI, Google ScholarWang, Y.-J., et al. 2015. Mycosystema 34:1209. https://doi.org/10.13346/j.mycosystema.140119 Google ScholarWhite, T. J., et al. 1990. 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Plant Dis. 106:1989. https://doi.org/10.1094/PDIS-09-21-2080-PDN Link, ISI, Google ScholarFunding: This work was supported by the Sichuan Institute of Public Welfare (A-2019N-18), Sichuan Science and Technology Plan Project (2021YFYZ0012), Key Project at Central Government Level: The Ability Establishment of Sustainable Use for Valuable Chinese Medicine Resources (2060302), and Major Project for the Development of Chinese Medicine Industry (Eighth Package) (510201202109711).The author(s) declare no conflict of interest.DetailsFiguresLiterature CitedRelated Vol. 107, No. 10 October 2023SubscribeISSN:0191-2917e-ISSN:1943-7692 Download Metrics Article History Issue Date: 1 Nov 2023Published: 28 Sep 2023First Look: 7 Mar 2023Accepted: 1 Mar 2023 Page: 3312 Information© 2023 The American Phytopathological SocietyFundingSichuan Institute of Public WelfareGrant/Award Number: A-2019N-18Sichuan Science and Technology Plan ProjectGrant/Award Number: 2021YFYZ0012Key Project at Central Government Level: The Ability Establishment of Sustainable Use for Valuable Chinese Medicine ResourcesGrant/Award Number: 2060302Major Project for the Development of Chinese Medicine Industry (Eighth Package)Grant/Award Number: 510201202109711Keywordsfield cropsfungipathogen detectionThe author(s) declare no conflict of interest.PDF download