First Report of Maize Ear Rot Caused by Exserohilum rostratum in Hainan Province in Southern China
2021; American Phytopathological Society; Volume: 106; Issue: 1 Linguagem: Inglês
10.1094/pdis-01-21-0044-pdn
ISSN1943-7692
AutoresSun Hua, Ning Guo, MA Hong-xia, Shusen Liu, Jie Shi,
Tópico(s)Plant-Microbe Interactions and Immunity
ResumoHomePlant DiseaseVol. 106, No. 1First Report of Maize Ear Rot Caused by Exserohilum rostratum in Hainan Province in Southern China PreviousNext DISEASE NOTE OPENOpen Access licenseFirst Report of Maize Ear Rot Caused by Exserohilum rostratum in Hainan Province in Southern ChinaHua Sun, Ning Guo, Hongxia Ma, Shusen Liu, and Jie ShiHua Sunhttps://orcid.org/0000-0002-1700-7845Plant Protection Institute of Hebei Academy of Agricultural and Forestry Sciences, IPM Centre of Hebei Province, Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture, Baoding 071000, Hebei, China, Ning GuoPlant Protection Institute of Hebei Academy of Agricultural and Forestry Sciences, IPM Centre of Hebei Province, Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture, Baoding 071000, Hebei, China, Hongxia Mahttps://orcid.org/0000-0002-0515-280XPlant Protection Institute of Hebei Academy of Agricultural and Forestry Sciences, IPM Centre of Hebei Province, Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture, Baoding 071000, Hebei, China, Shusen Liuhttps://orcid.org/0000-0002-4012-445XPlant Protection Institute of Hebei Academy of Agricultural and Forestry Sciences, IPM Centre of Hebei Province, Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture, Baoding 071000, Hebei, China, and Jie Shi†Corresponding author: J. Shi; E-mail Address: shij99@163.comPlant Protection Institute of Hebei Academy of Agricultural and Forestry Sciences, IPM Centre of Hebei Province, Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture, Baoding 071000, Hebei, China AffiliationsAuthors and Affiliations Hua Sun Ning Guo Hongxia Ma Shusen Liu Jie Shi † Plant Protection Institute of Hebei Academy of Agricultural and Forestry Sciences, IPM Centre of Hebei Province, Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture, Baoding 071000, Hebei, China Published Online:29 Dec 2021https://doi.org/10.1094/PDIS-01-21-0044-PDNAboutSectionsPDF ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Maize (Zea mays L.) is one of three major grain crops in China, with production reaching 261 million tons in 2019 (NBS 2020). Some fungi cause maize ear rot, which leads to significant yield and quality losses. In 2016, about 5% of maize ears were dark brown and covered with a white mold in seed production fields in Lingshui, Hainan Province, China. These ears were brought back to the laboratory for analysis. Molded kernels were surface sterilized in 75% ethanol for 3 min and in 10% sodium hypochlorite for 3 min, subsequently rinsed three times in sterile distilled water, placed onto potato dextrose agar (PDA), and incubated at 28°C in the dark for 3 days. Mycelia tips grown from kernels were transferred into fresh PDA plates. Seven fungal isolates with similar morphology characteristics were obtained, and three of them were identified by morphology and molecular identification. The colonies grew rapidly. The aerial mycelia turned white to black with age. Conidia were straight to slightly curved, oval, pyriform or geniculate, brown to dark brown, and had two to seven septa, with both basal and caudal septa thicker and darker than others, 39.47 to 78.66 × 13.96 to 22.78 μm, with a distinctly protruding hilum swelled from the basal cell. Conidiophores were dark brown, with geniculate tip and many septa. For molecular identification, genomic DNA of isolate was extracted from mycelia. The internal transcribed spacer (ITS), 1,3,8-trihydroxynaphthalene reductase (Brn), and glyceraldehyde-3-phosphate dehydrogenase-like (Gpd) genes were amplified with primers ITS1/ITS4 (White et al. 1990), Brn01/Brn02 (Shimizu et al. 1998), and gpd1/gpd2 (Berbee et al. 1999), respectively. BLASTn analysis showed high identities with Exserohilum rostratum (ITS, LT837845.1, 100%; Brn, AY621165.1, 99.87%; Gpd, LT882543.1, 99.75%). Sequences of ITS, Brn, and Gpd were deposited in GenBank with accession numbers MW362495, MW363953, and MW363954, respectively. Based on morphological characteristics and molecular analysis, the isolate was identified as E. rostratum (Hernández-Restrepo et al. 2018). Koch's postulates were completed by using ears of maize inbred line Huangzaosi and Chang7-2 growing in the experimental field of Baoding, Hebei Province. Three days post silk emergence, each of the four maize ears was injected with 2 ml of conidial suspension (1 × 106 conidia/ml) of isolate ZBSF005 through the silk channel. In the control groups, three ears were inoculated with an equal amount of sterile distilled water. The inoculated ears grew under natural conditions for 30 days; the diseased kernels and ear tips were black-brown and the surface covered with a white or gray-black mildew layer. The kernels with severe infection were wizened. But the bract could not be infected by the pathogen. Meanwhile, the control remained asymptomatic. The same fungus was successfully reisolated from the inoculated kernels, and its identity was confirmed by morphological and molecular biology approaches, thus fulfilling Koch's postulates. E. rostratum has been reported to cause leaf spots in a wide range of hosts, such as Calathea picturata, Lagenaria siceraria, Saccharum officinarum, Ananas comosus, Hevea brasiliensis, Zea mays, and so on (Ahmadpour et al. 2013; Chern et al. 2011; Choudhary et al. 2018), and it was also reported to cause root rot in Lactuca saliva (Alamri et al. 2019). To our knowledge, this is the first report of E. rostratum causing maize ear rot in China. The pathogen was simultaneously inoculated to eight maize inbred lines in Hebei Province, but the disease only occurred in some varieties and the incidence area was large. Therefore, attention should be paid to the ear rot caused by this pathogen in the breeding process.The author(s) declare no conflict of interest.References:Ahmadpour, A., et al. 2013. Australas. Plant Dis. Notes 8:97. https://doi.org/10.1007/s13314-013-0105-y Crossref, Google ScholarAlamri, S. A. M., et al. 2019. Biol. Control 128:76. https://doi.org/10.1016/j.biocontrol.2018.09.014 Crossref, ISI, Google ScholarBerbee, M. L., et al. 1999. Mycologia 91:964. https://doi.org/10.1080/00275514.1999.12061106 Crossref, ISI, Google ScholarChern, L. L., et al. 2011. Plant Dis. 95:1033. https://doi.org/10.1094/PDIS-12-10-0939 Link, ISI, Google ScholarChoudhary, M., et al. 2018. Plant Dis. 102:2042. https://doi.org/10.1094/PDIS-02-18-0315-PDN Link, ISI, Google ScholarHernández-Restrepo, M., et al. 2018. Persoonia 41:71. https://doi.org/10.3767/persoonia.2018.41.05 Crossref, ISI, Google ScholarNational Bureau of Statistics of China (NBS). 2020. China Statistical Yearbook. China Statistics Press, Beijing, China. Google ScholarShimizu, K., et al. 1998. J. Gen. Appl. Microbiol. 44:251. https://doi.org/10.2323/jgam.44.251 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: Supported by HAAFS Agricultural Science and Technology Innovation Project (2019-4-1B-4) and China Agriculture Research System (CARS-02-14).The author(s) declare no conflict of interest.DetailsFiguresLiterature CitedRelated Vol. 106, No. 1 January 2022SubscribeISSN:0191-2917e-ISSN:1943-7692 DownloadCaptionSymptoms of Macrophomina phaseolina in melon (R. Cohen et al.). Photo credit: R. Cohen. Jute plant infected with papaya ring spot virus (PRSV) (sample MG16-004) (C. Biswas et al.). Photo credit: V. Ramesh Babu. Metrics Downloaded 643 times Article History Issue Date: 7 Feb 2022Published: 29 Dec 2021First Look: 20 Jul 2021Accepted: 16 Jul 2021 Page: 314 Information© 2021 The American Phytopathological SocietyFundingHAAFS Agricultural Science and Technology Innovation ProjectGrant/Award Number: 2019-4-1B-4China Agriculture Research SystemGrant/Award Number: CARS-02-14KeywordsExserohilum rostratummaizeear rotThe author(s) declare no conflict of interest.PDF downloadCited ByAssociation of Exserohilum rostratum with ginger:- Morphological characterization, phylogenetic relationships and pathogenicity assays24 March 2022 | Australasian Plant Pathology, Vol. 51, No. 3
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