First Report of Black Rot Caused by Phoma cucurbitacearum on Momordica charantia in Korea

HomePlant DiseaseVol. 99, No. 5First Report of Black Rot Caused by Phoma cucurbitacearum on Momordica charantia in Korea PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Black Rot Caused by Phoma cucurbitacearum on Momordica charantia in KoreaI. Y. Choi, J. H. Kim, W. H. Lee, J. H. Park, and H. D. ShinI. Y. ChoiSearch for more papers by this author, J. H. KimSearch for more papers by this author, W. H. LeeSearch for more papers by this author, J. H. ParkSearch for more papers by this author, and H. D. ShinSearch for more papers by this authorAffiliationsAuthors and Affiliations I. Y. Choi J. H. Kim , Jeollabuk-do Agricultural Research and Extension Services, Iksan 570-704, Korea W. H. Lee , Department of Agricultural Biology, Chonbuk National University, Jeonju 561-765, Korea J. H. Park H. D. Shin , Division of Environmental Science and Ecological Engineering, Korea University, Seoul 136-701, Korea. Published Online:29 May 2015https://doi.org/10.1094/PDIS-10-14-1035-PDNAboutSectionsSupplemental ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Momordica charantia L. (Cucurbitaceae, bitter gourd or bitter melon) is native to India and tropical Asia where it is widely cultivated regions for the edible fruit that are used both as a vegetable and for medicinal purposes. During summer to autumn of 2013 and 2014, a black rot was observed on fruit of bitter gourd cvs. Super Balsam Pear and NS454 at an incidence of 2 to 3% in Jeongeup and Iksan, Korea. Early symptoms were small, circular, water-soaked lesions at the blossom-end of fruits. The infected tissue contained blackish pycnidia from which masses of conidia were released under humid conditions. Pycnidia were yellow-brown to dark brown, globose to subglobose with a distinct ostiole, and 125 to 185 μm in diameter. Conidia were hyaline, smooth, oval to ellipsoidal, aseptate or medianly 1-septate, rarely 2-septate, slightly constricted at the septa, 5 to 12 × 3 to 5 μm, and contained small oil drops. These morphological characteristics were consistent with those of Phoma cucurbitacearum (Fr.: Fr.) Sacc., for which the names Stagonosporopsis cucurbitacearum (Fr.) Aveskamp, Gruyter & Verkley and Didymella bryoniae (Auersw.) Rehm were formerly applied to the teleomorph (1,3). The colony morphology on potato dextrose agar (PDA) was white, compact to floccose with aerial mycelium; and the abaxial plate surface a lead black. A representative isolate was deposited in the Korean Agricultural Culture Collection (Accession No. KACC47770) and used for a pathogenicity test and molecular analysis. Fungal DNA was extracted, and the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) amplified with primers ITS1/ITS4 and sequenced directly. The resulting 560-bp sequence was deposited in GenBank (Accession No. KM489071), and showed 99.8% similarity with ITS sequences of S. cucurbitacearum (EU167573 and JQ936151). To confirm pathogenicity of the isolate, inoculum was prepared by harvesting conidia from 2-week-old cultures on PDA plates. A conidial suspension (2 × 107 conidia/ml) was sprayed until runoff onto five healthy fruit (cv. NS454). Control fruit of the same cultivar were sprayed with sterilized water. The plants were covered with plastic bags to maintain a relative humidity of 100% for 24 h, and then maintained in the field. Water-soaked lesions containing black pycnidia appeared on the inoculated fruit 5 days after inoculation, and were identical to those observed in the field. P. cucurbitacearum was reisolated from symptomatic fruit tissues, fulfilling Koch’s postulates. No symptoms were observed on control plants. The pathogenicity test was carried out twice with similar results. Black rot associated with P. cucurbitacearum on bitter gourd has been known from India, Malaysia, Brunei Darussalam, China, and Tanzania (2,4). To our knowledge, this is the first report of P. cucurbitacearum on bitter gourd in Korea. The presence of P. cucurbitacearum on bitter gourd in Asia could be a potentially serious threat to this plant.References:(1) Boerema, G. H., et al. 2004. Phoma Identification Manual: Differentiation of Specific and Infra-Specific Taxa in Culture. CABI Publishing, Wallingford, UK. Crossref, Google Scholar(2) Farr, D. F., and Rossman, A. Y. Fungal Databases. Syst. Mycol. Microbiol. Lab., Online publication, ARS, USDA, Retrieved October 14, 2014. Google Scholar(3) Punithalingam, E., and Holliday,P. 1972. CMI Descriptions of Pathogenic Fungi and Bacteria. No. 332. Google Scholar(4) Singh, K., et al. 1996. Indian Phytopathol. 49:294. Google ScholarDetailsFiguresLiterature CitedRelated Vol. 99, No. 5 May 2015SubscribeISSN:0191-2917e-ISSN:1943-7692 Metrics Article History Issue Date: 29 May 2015Published: 29 May 2015First Look: 11 Dec 2014Accepted: 3 Dec 2014 Page: 727 Information© 2015 The American Phytopathological SocietyCited byPopulation Structure of Stagonosporopsis Species Associated with Cucurbit Gummy Stem Blight in KoreaThe Plant Pathology Journal, Vol. 38, No. 5Didymella bryoniae (gummy stem blight of cucurbits)CABI Compendium, Vol. CABI CompendiumPhoma diseases: Epidemiology and control17 June 2020 | Plant Pathology, Vol. 69, No. 7