First Report of Ceratocystis Lukuohia on Metrosideros Polymorpha on the Island of Kaua‘i, Hawai‘i

HomePlant DiseaseVol. 103, No. 11First Report of Ceratocystis lukuohia on Metrosideros polymorpha on the Island of Kaua‘i, Hawai‘i PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Ceratocystis lukuohia on Metrosideros polymorpha on the Island of Kaua‘i, Hawai‘iEva Brill, Marc A. Hughes, Wade P. Heller, and Lisa M. KeithEva Brill†Corresponding author: E. Brill; E-mail Address: ebrill@hawaii.eduhttp://orcid.org/0000-0003-2463-0296University of Hawai‘i at Mānoa, College of Tropical Agriculture and Human Resources, Komohana Research and Extension Center, Hilo, HI 96720Search for more papers by this author, Marc A. Hugheshttp://orcid.org/0000-0003-3652-3412University of Hawai‘i at Mānoa, College of Tropical Agriculture and Human Resources, Komohana Research and Extension Center, Hilo, HI 96720Search for more papers by this author, Wade P. HellerUniversity of Hawai‘i at Mānoa, College of Tropical Agriculture and Human Resources, Komohana Research and Extension Center, Hilo, HI 96720Search for more papers by this author, and Lisa M. Keithhttp://orcid.org/0000-0001-9974-1818USDA Agricultural Research Service, Tropical Plant Genetic Resources and Disease Research Unit, Hilo, HI 96720Search for more papers by this authorAffiliationsAuthors and Affiliations Eva Brill1 † Marc A. Hughes1 Wade P. Heller1 Lisa M. Keith2 1University of Hawai‘i at Mānoa, College of Tropical Agriculture and Human Resources, Komohana Research and Extension Center, Hilo, HI 96720 2USDA Agricultural Research Service, Tropical Plant Genetic Resources and Disease Research Unit, Hilo, HI 96720 Published Online:28 Aug 2019https://doi.org/10.1094/PDIS-05-19-0987-PDNAboutSections ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat ‘Ōhi‘a (Metrosideros polymorpha) is the dominant and most ecologically and culturally important native tree in the Hawaiian Islands. Rapid ‘ōhi‘a death (ROD), a lethal disease complex caused by the fungi Ceratocystis lukuohia and C. huliohia I. Barnes, T.C. Harrin. & L.M. Keith, has caused widespread ‘ōhi‘a mortality across Hawai‘i Island (Barnes et al. 2018). Of the two species, C. lukuohia is more aggressive and is responsible for most of the ‘ōhi‘a mortality caused by ROD on Hawai‘i Island (Barnes et al. 2018). During helicopter surveys in December 2018, Hawai‘i Department of Land and Natural Resources staff on the Island of Kaua‘i detected three ‘ōhi‘a trees behind Kalalea Mountain that had completely wilted crowns with brown leaves attached. Visual inspection of the outer sapwood using a hatchet revealed brown to black discoloration typical of ROD. Samples from the three trees were collected from discolored portions of the sapwood using a flame-sterilized drill bit and mailed to the USDA Agricultural Research Service in Hilo for testing using a diagnostic qPCR assay developed by Heller and Keith (2018); C. lukuohia DNA was detected in all samples collected. Carrot baiting (Moller and DeVay 1968) was used to isolate the fungus from symptomatic wood tissues of each tree. A single perithecium per sample was aseptically transferred to 10% V8 agar, and the resulting multispore isolates looked identical to C. lukuohia isolates collected from Hawai‘i Island. PCR amplification and sequencing of the internal transcribed spacer (ITS) region of rDNA, β-tubulin (tub2), and cerato-platanin loci were carried out for one isolate, P19-12. BLASTn analyses of the sequence data (GenBank accession nos. MK863991, MK863992, and MK863993) showed that the isolate was 100% identical for 582 (ITS), 564 (tub2), and 443 (cerato-platanin) bp of corresponding sequences from C. lukuohia P14-1-1 (KP203957/ITS, KU043263/tub2, and KU043257/cerato-platanin). To confirm pathogenicity, five ‘ōhi‘a seedlings (mean height = 0.6 m) were inoculated with filter paper discs soaked in a 1.2 × 106 spore/ml suspension of P19-12 following the method of Keith et al. (2015). Two control plants were inoculated with filter discs soaked in sterile water. Plants were maintained at 24°C with 12 h light in a growth chamber. The experiment was conducted twice. Seven of 10 seedlings wilted and died within 4 weeks of inoculation. Dissection of the 10 seedlings revealed staining of the xylem throughout the dead plants and staining 15 to 21 cm above the inoculation points in the asymptomatic plants. C. lukuohia was reisolated from all 10 plants and morphologically (colonized carrot baits) and molecularly (cerato-platanin) identified, thus fulfilling Koch’s postulates. All control plants were asymptomatic and upon dissection only showed minor xylem staining (<1 cm) at the inoculation point. The fungus was not recovered on carrot baits or detected by qPCR. To our knowledge, this is the first report of C. lukuohia beyond Hawai‘i Island. Owing to its aggressive nature, this discovery is of great concern for the health and proliferation of ‘ōhi‘a on Kaua‘i. Further work is needed to assess the full impact of ROD on this island.The author(s) declare no conflict of interest.References:Barnes, I., et al. 2018. Persoonia 40:154. https://doi.org/10.3767/persoonia.2018.40.07 Crossref, ISI, Google ScholarHeller, W. P., and Keith, L. M. 2018. Phytopathol. 108:1395. https://doi.org/10.1094/PHYTO-09-17-0311-R Link, ISI, Google ScholarKeith, L. M., et al. 2015. Plant Dis. 99:1276. https://doi.org/10.1094/PDIS-12-14-1293-PDN Link, ISI, Google ScholarMoller, W. J., and DeVay, J. E. 1968. Phytopathol. 58:123. ISI, Google ScholarThe author(s) declare no conflict of interest.DetailsFiguresLiterature CitedRelated Vol. 103, No. 11 November 2019SubscribeISSN:0191-2917e-ISSN:1943-7692 DownloadCaptionAdvanced symptoms of bacterial blotch disease on mushroom caps (Osdaghi et al.). Photo credit: C. Bull. Powdery mildew caused by Golovinomyces neosalviae on Salvia fruticosa (Soylu et al.). Photo credit: S. Soylu. Metrics Article History Issue Date: 4 Nov 2019Published: 28 Aug 2019First Look: 26 Jun 2019Accepted: 21 Jun 2019 Page: 2961 Information© 2019 The American Phytopathological SocietyKeywords‘ōhi‘arapid ‘ōhi‘a deathvascular wilt, forest pathogens, invasive speciesThe author(s) declare no conflict of interest.Cited byEnvironmental monitoring for invasive fungal pathogens of ʽŌhiʽa (Metrosideros polymorpha) on the Island of Hawaiʽi10 December 2022 | Biological Invasions, Vol. 25, No. 2Rapid Response to a Tree Seed Conservation Challenge in Hawai‘i Through Crowdsourcing, Citizen Science, and Community Engagement20 July 2020 | Journal of Sustainable Forestry, Vol. 41, No. 7A framework for establishing a rapid ‘Ōhi‘a death resistance program25 January 2022 | New Forests, Vol. 11Ceratocystis lukuohiaCABI Compendium, Vol. CABI CompendiumRapid ‘Ōhi‘a Death in Hawai‘iNest Site Characteristics of Two Endangered Seabirds in Montane Wet Forests on the Island of Kaua‘i, Hawai‘i, USAWaterbirds, Vol. 44, No. 4Hawai‘i forest review: Synthesizing the ecology, evolution, and conservation of a model systemPerspectives in Plant Ecology, Evolution and Systematics, Vol. 52Spatial Patterns of ‘Ōhi‘a Mortality Associated with Rapid ‘Ōhi‘a Death and Ungulate Presence4 August 2021 | Forests, Vol. 12, No. 8Screening of Metrosideros polymorpha (‘ōhi‘a) varieties for resistance to Ceratocystis lukuohia26 November 2020 | Forest Pathology, Vol. 51, No. 1Influence of Culture Media and Temperature on Growth and Sporulation of Ceratocystis lukuohiaPacific Science, Vol. 74, No. 4Pathogenicity, Symptom Development, and Colonization of Metrosideros polymorpha by Ceratocystis lukuohiaMarc A. 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