Additions to the Knowledge of the Fungal Order Eurotiales in Korea: Eight Undescribed Species

Eurotiales is a relatively large order of Ascomycetes, well-known for their ability to produce secondary metabolites with potential beneficial applications. To understand their diversity and distribution, different environmental sources including soil, freshwater, insect, and indoor air were investigated. Eight strains of Eurotiales were isolated and identified based on their morphological characters and a multi-gene phylogenetic analysis of the ITS, BenA, CaM, and RPB2 regions. We identified eight taxa that were previously not reported from Korea: Aspergillus baeticus, A. griseoaurantiacus, A. spinulosporus, Penicillium anthracinoglaciei, P. labradorum, P. nalgiovense, Talaromyces atroroseus, and T. georgiensis. Detailed descriptions, illustrations, and phylogenetic tree for the eight new records species are presented, and information regarding the records is also discussed.

Fungal Planet description sheets: 1478-1549

Novel species of fungi described in this study include those from various countries as follows: Australia, Aschersonia mackerrasiae on whitefly, Cladosporium corticola on bark of Melaleuca quinquenervia, Penicillium nudgee from soil under Melaleuca quinquenervia, Pseudocercospora blackwoodiae on leaf spot of Persoonia falcata, and Pseudocercospora dalyelliae on leaf spot of Senna alata. Bolivia, Aspicilia lutzoniana on fully submersed siliceous schist in high-mountain streams, and Niesslia parviseta on the lower part and apothecial discs of Erioderma barbellatum on a twig. Brazil, Cyathus bonsai on decaying wood, Geastrum albofibrosum from moist soil with leaf litter, Laetiporus pratigiensis on a trunk of a living unknown hardwood tree species, and Scytalidium synnematicum on dead twigs of unidentified plant. Bulgaria, Amanita abscondita on sandy soil in a plantation of Quercus suber. Canada, Penicillium acericola on dead bark of Acer saccharum, and Penicillium corticola on dead bark of Acer saccharum. China, Colletotrichum qingyuanense on fruit lesion of Capsicum annuum. Denmark, Helminthosphaeria leptospora on corticioid Neohypochnicium cremicolor. Ecuador (Galapagos), Phaeosphaeria scalesiae on Scalesia sp. Finland, Inocybe jacobssonii on calcareous soils in dry forests and park habitats. France, Cortinarius rufomyrrheus on sandy soil under Pinus pinaster, and Periconia neominutissima on leaves of Poaceae. India, Coprinopsis fragilis on decaying bark of logs, Filoboletus keralensis on unidentified woody substrate, Penicillium sankaranii from soil, Physisporinus tamilnaduensis on the trunk of Azadirachta indica, and Poronia nagaraholensis on elephant dung. Iran, Neosetophoma fici on infected leaves of Ficus elastica. Israel, Cnidariophoma eilatica (incl. Cnidariophoma gen. nov.) from Stylophora pistillata. Italy, Lyophyllum obscurum on acidic soil. Namibia, Aureobasidium faidherbiae on dead leaf of Faidherbia albida, and Aureobasidium welwitschiae on dead leaves of Welwitschia mirabilis. Netherlands, Gaeumannomycella caricigena on dead culms of Carex elongata, Houtenomyces caricicola (incl. Houtenomyces gen. nov.) on culms of Carex disticha, Neodacampia ulmea (incl. Neodacampia gen. nov.) on branch of Ulmus laevis, Niesslia phragmiticola on dead standing culms of Phragmites australis, Pseudopyricularia caricicola on culms of Carex disticha, and Rhodoveronaea nieuwwulvenica on dead bamboo sticks. Norway, Arrhenia similis half-buried and moss-covered pieces of rotting wood in grass-grown path. Pakistan, Mallocybe ahmadii on soil. Poland, Beskidomyces laricis (incl. Beskidomyces gen. nov.) from resin of Larix decidua ssp. polonica, Lapidomyces epipinicola from sooty mould community on Pinus nigra, and Leptographium granulatum from a gallery of Dendroctonus micans on Picea abies. Portugal, Geoglossum azoricum on mossy areas of laurel forest areas planted with Cryptomeria japonica, and Lunasporangiospora lusitanica from a biofilm covering a biodeteriorated limestone wall. Qatar, Alternaria halotolerans from hypersaline sea water, and Alternaria qatarensis from water sample collected from hypersaline lagoon. South Africa, Alfaria thamnochorti on culm of Thamnochortus fraternus, Knufia aloeicola on Aloe gariepensis, Muriseptatomyces restionacearum (incl. Muriseptatomyces gen. nov.) on culms of Restionaceae, Neocladosporium arctotis on nest of cases of bag worm moths (Lepidoptera, Psychidae) on Arctotis auriculata, Neodevriesia scadoxi on leaves of Scadoxus puniceus, Paraloratospora schoenoplecti on stems of Schoenoplectus lacustris, Tulasnella epidendrea from the roots of Epidendrum × obrienianum, and Xenoidriella cinnamomi (incl. Xenoidriella gen. nov.) on leaf of Cinnamomum camphora. South Korea, Lemonniera fraxinea on decaying leaves of Fraxinus sp. from pond. Spain, Atheniella lauri on the bark of fallen trees of Laurus nobilis, Halocryptovalsa endophytica from surface-sterilised, asymptomatic roots of Salicornia patula, Inocybe amygdaliolens on soil in mixed forest, Inocybe pityusarum on calcareous soil in mixed forest, Inocybe roseobulbipes on acidic soils, Neonectria borealis from roots of Vitis berlandieri × Vitis rupestris, Sympoventuria eucalyptorum on leaves of Eucalyptus sp., and Tuber conchae from soil. Sweden, Inocybe bidumensis on calcareous soil. Thailand, Cordyceps sandindaengensis on Lepidoptera pupa, buried in soil, Ophiocordyceps kuchinaraiensis on Coleoptera larva, buried in soil, and Samsoniella winandae on Lepidoptera pupa, buried in soil. Taiwan region (China), Neophaeosphaeria livistonae on dead leaf of Livistona rotundifolia. Türkiye, Melanogaster anatolicus on clay loamy soils. UK, Basingstokeomyces allii (incl. Basingstokeomyces gen. nov.) on leaves of Allium schoenoprasum. Ukraine, Xenosphaeropsis corni on recently dead stem of Cornus alba. USA, Nothotrichosporon aquaticum (incl. Nothotrichosporon gen. nov.) from water, and Periconia philadelphiana from swab of coil surface. Morphological and culture characteristics for these new taxa are supported by DNA barcodes. Citation: Crous PW, Osieck ER, Shivas RG, et al. 2023. Fungal Planet description sheets: 1478-1549. Persoonia 50: 158- 310. https://doi.org/10.3767/persoonia.2023.50.05.

Isolation and Characterization of Four Unrecorded Mucor Species in Korea

During an investigation of fungi of the order Mucorales from freshwater and sediment samples in Korea, we isolated six strains, NNIBRFG6649, NNIBRFG6255, NNIBRFG1498, CNUFC-YJ13, CNUFC-YR7, and NNIBRFG2739. The morphology and phylogeny of these strains were analyzed. Based on the morphological characteristics and molecular data from internal transcribed spacer (ITS) region, the isolates NNIBRFG6649 and NNIBRFG6255 were identified as Mucor abundans, and M. aligarensis, respectively. The isolates NNIBRFG1498 and CNUFC-YJ13 were identified as M. moelleri, whereas the isolates CNUFC-YR7 and NNIBRFG2739 were identified as M. heterogamus. To the best of our knowledge, M. abundans, M. aligarensis, M. moelleri, and M. heterogamus have not yet been reported in Korea.

Characterization of Two New Records of Zygomycete Species Belonging to Undiscovered Taxa in Korea

During a biodiversity survey of undiscovered taxa in Korea, two zygomycetous fungal strains were isolated. The first strain, EML-FSDY6-1 was isolated from a soil sample collected at Dokdo Island in the East Sea of Korea in 2013, and the second strain, EML-DG-NH3-1 was isolated from a rat dung sample collected at Chonnam National University garden, Gwangju, Korea in 2014. Based on the morphological characteristics and phylogenetic analysis of the internal transcribed spacer, 18S and 28S rDNA, actin and translation elongation factor-1α genes. EML-FSDY6-1 and EML-DG-NH3-1 isolates were confirmed as zygomycete species, Absidia pseudocylindrospora and Absidia glauca, respectively. Neither species has previously been described in Korea.

Confirmation of Two Undescribed Fungal Species from Dokdo of Korea Based on Current Classification System Using Multi Loci

Using dilution plating method, 47 fungal isolates were obtained from a soil sample collected from Dokdo in the East Sea of Korea in 2013. In this study, two fungal isolates, EML-MFS30-1 and EML-DDSF4, were confirmed as undescribed species, Metarhizium guizhouense and Mortierella oligospora in Korea based on current classification system using multi loci including rDNA internal transcribed spacer, large subunit, small subunit, and β-tubulin (BTUB) genes. Herein, detailed morphological descriptions on characters of the undescribed fungal species as well as their molecular phylogenetic status are provided with comparisons to related species.

A New Record of Penicillium raphiae Isolated from Agricultural Soil of Ulleung Island, Korea

A fungal isolate EML-NCP01 was recovered from agricultural soil in Ulleung Island, Korea. Phylogenetic analysis of internal transcribed spacer and β-tubulin genes identified the isolate as the Penicillium species P. raphiae. Morphologically, the EML-NCP01 isolate was identical to the previous description of P. raphiae. The species presented here has not been reported in Korea.

First Report of Powdery Mildew on Spanish Needles (Bidens bipinnata) Caused by Podosphaera xanthii in Korea

Spanish needles (Bidens bipinnata L.) is an annual herb that belongs to a genus of flowering plants in family Asteraceae native to United States, and tropical regions around world. The plant produces important flavonoid compounds quercitin and hyperoside that function as anti-allergens, anti-inflammatories, anti-microbials, and anti-cancer agents. Between July and October 2011 and 2012, white superficial mycelia were observed initially on leaf and stem portions, but later progressed to the flower head. Surveys showed that the disease was widespread in Gwangju and most areas of South Korea. Abundant, necrotic, dark brown spots showing chasmothecia were frequently observed in October and were abundant on the adaxial surface of leaves. Chasmothecia were blackish brown to yellow without typical appendages. They ranged from 51.2 to 71.1 (mean 66.8) μm in diameter. Conidia were formed singly and the primary conidia were ellipsoid, rounded at the apex, truncated base, and ranged from 25.4 to 33.2 (mean 27.3) μm long × 10.2 to 12.2 (mean 11.3) μm wide. Conidiophores were erect, 60.1 to 101.3 (mean 98.3) μm long × 6.2 to 9.2 (mean 7.3) μm wide. From extracted genomic DNA, the internal transcribed spacer (ITS) region inclusive of 5.8S and 28S rDNA was amplified with ITS1F (5'-TCCGTAGGTGAACCTGCGG-3') and LR5F (5'-GCTATCCTGAGGGAAAC-3'), and LROR (5'-ACCCGCTGAACTTAAGC-3') and LR5F primer sets, respectively. rDNA ITS (GenBank Accession No. JX512555) and 28S (JX512556) homologies of the fungus (EML-BBPW1) represented 99.6% (532/534) and 100% (661/661) identity values with Podosphaera xanthii (syn. P. fusca) AB040349 and P. xanthii (syn. P. fusca) AB462798, respectively. The rDNA sequence analysis revealed that the causal fungus matched P. xanthii (syn. P. fusca), forming a xanthii/fusca group (3,4). A pathogenicity test was performed on three plants in a greenhouse. The treated leaves were sealed in vinyl pack in humid condition for 2 days. Seven days after inoculation, similar symptoms were observed on the inoculated Spanish needles plant leaves. No symptoms were observed on control plants treated with distilled water. Koch's postulates were fulfilled by re-observing the fungal pathogen on the inoculated leaves. Podosphaera (syn. Sphaerotheca) xanthii (or fusca) has been known as an ubiquitous species with a broad host range. So far, five records regarding P. xanthii (=P. fusca) have been found in plants of genus Bidens. P. xanthii has been reported to occur on B. cernua in Belarus and Switzerland. In addition, the powdery mildew species was reported to occur on B. frondosa and B. tripartita in Korea, Russia, and Switzerland (2). To our knowledge, this is the first report of powdery mildew caused by P. xanthii on Spanish needles (B. bipinnata) in Korea. References: (1) U. Braun et al. Schlechtendalia 10:91, 2003. (2) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , 2012. (3) H. B. Lee. J. Microbiol. 51:1075, 2012. (4) S. Takamatsu, et al. Persoonia 24:38, 2010.

First Report of Powdery Mildew Caused by Erysiphe platani on Sycamore (Platanus occidentalis) in South Korea

Platanus occidentalis L. (sycamore) is an important shade tree distributed throughout the Northern Hemisphere and in South Korea. It has been widely used as an ornamental tree, especially in urban regions and by roadsides. The average rate of roadside planting throughout South Korea covers about 5.7% (up to 38% in Seoul), equivalent to 0.36 million trees. In early July 2012, after a rainy spell in summer, an outbreak of powdery mildew on sycamore was first observed on roadside trees in Gwangju, a southern province of South Korea. A more extensive nationwide survey revealed no powdery mildew in northern or central regions of South Korea. The disease has spread rapidly within Gwangju, even though fungicide applications were carried out after the rainy spell. Major symptoms included white, superficial mycelia, grey to brown lesions on the surface of the leaves due to the presence of a hyperparasite (tentatively identified as Ampelomyces sp.), a slight chlorosis, and severe leaf distortion followed by defoliation. Conidiophores were produced singly, straight, and unbranched, with lengths of 35.2 to 315.2 μm (average 170.4 μm). Conidia were ellipsoid or doliiform, ranging in size from 34.9 to 47.4 μm (average 38.2 μm) long × 16.5 to 26.8 μm (average 23.9 μm) wide. Primary conidia had a truncate base and rounded apex; secondary conidia had both a truncate base and apex. The conidial outer surface had a reticulated wrinkling. Cleistothecia (i.e., sexual spore structures) were not found during the survey, which extended from July to October. These characteristics and the host species match those of Microsphaera platani (syn. Erysiphe platani), which was described on P. occidentalis in Washington State (2). Fungal rDNA was amplified using primers ITS1 and LR5F (4) for one sample (EML-PLA1, GenBank JX485651). BLASTn searches of GenBank revealed high sequence identity to E. platani (99.5% to JQ365943 and 99.3% to JQ365940). Recently, Liang et al. (3) reported the first occurrence of powdery mildew by E. platani on P. orientalis in China based only on its morphology. Thus, in this study, author could only use ITS sequence data from the United States and Europe to characterize the isolate. To date, nine records of powdery mildews of Platanus spp. have been reported worldwide: on P. hispanica from Brazil, Japan, Hungary, and Slovakia; P. orientalis from Israel; P. racemosa from the United States; P. × acerifolia from the United Kingdom and Germany; and Platanus sp. from Argentina and Australia (1). Interestingly, the hyperparasite, Ampelomyces sp., was found with E. platani, suggesting that there may be some level of biocontrol in nature. Pathogenicity was confirmed by gently pressing diseased leaves onto six leaves of healthy sycamore plants in the field in September. The treated leaves were sealed in sterilized vinyl pack to maintain humid condition for 2 days. Similar symptoms were observed on the inoculated leaves 10 days after inoculation. Koch's postulates were fulfilled by re-observing the fungal pathogen. To our knowledge, this is the first report of powdery mildew caused by E. platani on sycamore in South Korea. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. http://nt.ars-grin.gov/fungaldatabases/ , 2012. (2) D. A. Glawe. Plant Health Progress, doi:10.1094/PHP-2003-0818-01-HN, 2003. (3) C. Liang et al. Plant Pathol. 57:375, 2008. (4) T. J White et al., pp. 315-322 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., ed. Academic Press, New York, 1990.

First Report of Crown Rot on Gypsophila (Gypsophila paniculata) Caused by Fusarium proliferatum in Korea

Gypsophilas commonly cultivated are Gypsophila elegans B. and G. paniculata L. In September of 2009 and 2010, a severe wilt symptom due to crown rot was observed on G. paniculata (cv. Bristol Fairy) in greenhouses in Yeosu, South Korea. The area of cultivation (~8 ha) in Yeosu covers 90% of production in the Jeonnam Province. Disease outbreak was 20 to 30% in affected greenhouses. Early symptoms included brown discoloration surrounding basal stems and slight wilting. Late symptoms included a sunken stem rot next to the roots, root rot, severe wilting, and dying plants. The causal fungus appeared to invade plants through the basal stem, causing a crown rot that prevented the plant from taking up water and nutrients. Crown rot occurred on young and mature plants. Ten fungal isolates were recovered from basal stems and roots of wilted plants. Microconidia were abundantly produced on potato dextrose agar (PDA), V8 juice agar (VA), carnation leaf agar (CLA), and oatmeal agar (OA). Microconidia were single celled, variable, oval-ellipsoid cylindrical, straight to curved, club-to-kidney shaped or spindle shaped on OA, more slender on VA. Macroconidia were not found on any media used. Microconidia on PDA were 5.9 to 15.1 (9.9) × 2.7 to 4.3 (3.5) μm. Germinated conidia (or false conidia) were often formed on CLA. Conidiophores as phialides were singly formed but often branched. Length of conidiophores was up to 31.1 μm on CLA. Small-sized chlamydospores were rarely found. Fusarium isolates (EML-GYP1, 2, and 3) were selected and identified. From extracted genomic DNA, the internal transcribed spacer (ITS) region including 5.8S rDNA was amplified using ITS1F (5'-CTTGGTCATTTAGAGGAAGT-3') and LR5F (5'-GCTATCCTGAGGGAAAC-3') primers. Sequence analyses by BLAST indicated that the isolates (GenBank HM560019, HM560020, and HM560021) were most similar to F. proliferatum (EF4534150) with sequence identity values of 99.3, 99.4, and 99.1%, respectively. The causal fungus was determined to be F. proliferatum based on morphological data and ITS rDNA sequences. Pathogenicity tests with the three isolates were performed on 10 plants of G. paniculata using the dipping method. Healthy roots and basal stems were soaked in a conidial suspension adjusted to ~1.2 × 10⁶ conidia/ml (distilled water) for 15 min. Plants were potted in sterile soil, kept in a humid chamber for 72 h, and moved to a greenhouse. The experiment was carried out in duplicate and repeated two times. Similar symptoms to those observed in the greenhouses were seen 7 days after inoculation. The causal fungus was reisolated from the artificially inoculated basal stems, fulfilling Koch's postulates. Control plants whose basal stems and roots were dipped in sterile water showed no crown rot and wilt symptoms. EML-GYP2 was determined to be the most pathogenic. Ten records of disease caused by three Fusarium species (Fusarium sp., F. oxysporum, and F. udum) have been found on gypsophilas (1), but only F. oxysporum has been reported to cause wilt on G. elgans in Korea (2). To our knowledge, this is the first report of crown rot on gypsophila caused by F. proliferatum in Korea as well as the world. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , October 27, 2010, (2) W.-G. Kim and H.-M. Koo. Page 381 in: List of Plant Diseases in Korea. The Korean Society of Plant Pathology, 2009.

First Report of Erysiphe quercicola Causing Powdery Mildew on Ubame Oak in Korea

Ubame oak (Quercus phillyraeoides A. Gray) is native to eastern Asia, including China, Korea, and Japan. In 2009 and 2010, a powdery mildew on Q. phillyraeoides growing in clusters and singly was observed in three locations on the campus of Chonnam National University, Gwangju, Korea. White superficial conidia of the powdery mildew fungus occurred on adaxial and abaxial surfaces. However, the white powdery growth was more abundant on the adaxial surface. Leaf symptoms commonly appeared white from May to October. Along with the typical white powdery mildew, spot and/or necrotic symptoms with irregular violet-to-wine red surfaces were also frequently observed on overwintered leaves. A voucher specimen has been deposited in EML (Environmental Microbiology Laboratory) herbarium collection, Chonnam National University (EML-QUP1). Conidia were commonly formed singly but also occurred in chains. Primary conidia were obovoid to ellipsoid, with a rounded apex and subtruncate base. Secondary conidia were generally obovoid to ellipsoid or sometimes cylindrical but dolioform when mature. The size was 30.1 to 43.2 (average 37.7) × 14.1 to 21.1 (average 18.1) μm with length/width ratio of 1.8 to 2.4 (average 2.1). Conidiophores were erect and up to 102.2 μm long. No chasmothecia were found. From extracted genomic DNA, the internal transcribed spacer (ITS) region inclusive of 5.8S rDNA was amplified with ITS1F (5'-CTTGGT CATTTAGAGGAAGT-3') and LR5F (5'-GCTATCCTGAGGGAAAC-3') primers (4). Sequence analysis by BLASTN search indicated that EML-QUP1 (GenBank Accession No. HQ328834) was closest to E. quercicola (GenBank Accession No. AB292691) with >99% identity (478 of 480), forming a monophyletic quercicola clade in the resulting phylogenetic analysis. The causal fungus was determined to be Erysiphe quercicola on the basis of morphology and sequence data analysis. Major genera including Cystotheca, Erysiphe, Microsphaera, and Phyllactinia have been reported to cause powdery mildews on Quercus plants. Until now, 22 Erysiphe species including E. abbreviata, E. alphitoides, E. calocladophora, E. gracilis, E. polygoni, and E. quercicola have been reported to cause powdery mildews on Quercus spp. (1). Of these, four Erysiphe species including E. alphitoides, E. gracilis, E. quercicola, and an unidentified Erysiphe sp. have been found on Q. phillyraeoides from Japan (1-3). E. quercicola was reported to occur on five Quercus species: Q. crispula, Q. phillyraeoides, and Q. serrata in Japan, Q. robur in Australia, and Quercus sp. in Australia, Iran, and Thailand (1). To our knowledge, this is the first report of leaf powdery mildew caused by E. quercicola on Q. phillyraeoides in Korea. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved October 7, 2010, from http://nt.ars-grin.gov/fungaldatabases/ , 2010. (2) S. Limkaisang et al. Mycoscience 47:327, 2006. (3) S. Takamatsu et al. Mycol. Res. 111:809, 2007. (4) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

First Report of Powdery Mildew on Trident Maple Caused by Sawadaea nankinensis in Korea

Trident maple (Acer buergerianum Miq.) is widely grown in Korea as an ornamental tree as well as for the art of bonsai. During 2008 and 2009, a powdery mildew was observed on trident maple plants at the campus of Chonnam National University, Gwangju, Korea. Further surveys revealed the disease to be widespread on this species in other areas including Jeonbuk and Chungnam provinces in Korea. White, superficial mycelia were observed on young shoots and leaves early in spring. Both macroconidia and microconidia were produced beginning in May and conidial production continued through the summer into September and October. Production of chasmothecia was observed starting in September and continued into October. Macroconidia were produced in chains that were sinuate in outline. Individual macroconidia were barrel shaped and 23.4 to 30.0 (26.6) × 15.6 to 21.1 (18.1) μm. Foot cells of macroconidial conidiophores were 26.7 to 110.7 (48) × 7.1 to 11.2 (8.8) μm with one to five following cells. Microconidia were broadly ellipsoidal to subglobose and 8.9 to 12.5 (10.5) × 4.3 to 5.8 (5.1) μm. Chasmothecia typically were formed on adaxial leaf surfaces and 193.2 to 238.1 (216.8) μm in diameter. Appendages bore uncinate to circinate apices and were 176.8 to 267.7 (211.5) × 4.3 to 8.0 (6.2) μm. From extracted genomic DNA, internal transcribed spacer (ITS) region inclusive of 5.8S rDNA was amplified with ITS1F (5'-CTTGGTCATTTAGAGGAAGT-3') and LR5F (5'-GCTATCCTGAGGGAAAC-3') primers. The causal fungus was determined to be Sawadaea nankinensis (F.L. Tai) S. Takam. & U. Braun (2) on the basis of morphological data and ITS rDNA sequences. A BLAST search of GenBank with an ITS sequence from this fungus determined that the five sequences exhibiting the highest max score values (1,811 to 2,004) were from S. nankinensis; these sequences produced max ident values from 94% to 99%. In contrast, max score and max ident values from sequences of other Sawadaea spp. were lower, including scores of 1,063 and 98% similarity for S. polyfida var. japonica, 915 and 97% for S. tulasnei, and 913 and 97% for S. bicornis. Pathogenicity tests were conducted on field-grown plants in two replicates. These plants were inoculated with a paintbrush to apply conidia (~5 × 10⁶/ml) collected from powdery-mildew-infected leaves. Inoculated plants developed powdery mildew symptoms within 5 days of inoculation and resembled those observed on naturally infected plants. S. nankinensis (synonym Uncinula nankinensis) was first reported on A. buergerianum from China in 1930 (2). Recently, S. nankinensis (F.L. Tai) S. Takam & U. Braun was reported to occur on A. buergerianum in Japan (3). Until now, three Sawadaea spp. (S. bicornis (Wallr.) Homma, S. negundinis Homma, and S. tulasnei (Fuckel) Homma) have been reported to cause powdery mildew on A. ginnala, but only S. bicornis (= U. circinata Cooke & Peck) has been reported to cause powdery mildew on A. ginnala in Korea (1). However, no Sawadaea sp. previously was reported to cause powdery mildew on A. buergerianum. To our knowledge, this is the first report of powdery mildew on trident maple (A. buergerianum) caused by S. nankinensis in Korea. References: (1) H. D. Shin. Erysiphaceae of Korea. National Institute of Agricultural Science and Technology, 2000. (2) F. L. Tai. Page 1517 in: Sylloge Fungorum Sinicorum. Science Press, Academia Sinica, Peking, 1979. (3) S. Takamatsu et al. Mycoscience 49:161, 2008.

First Report of Stem Blight on Perilla (Perilla frutescens) Caused by Corynespora cassiicola in Korea

Perilla or kkaennip (Perilla frutescens (L.) Britton), an annual herb of the mint family, Lamiaceae, is used in salads and kimchi and for wrapping sliced raw fish. In September 2007, a disease occurred on greenhouse-produced perilla (cv. Manchu) in Gwangyang and Jeonnam provinces, Korea. Symptoms included leaf blight and irregularly shaped stem lesions approximately 1 to 3 cm long. Plants eventually died. In some greenhouses, 10 to 30%, and occasionally as much as 70%, of the plants were affected. Isolations on potato dextrose agar yielded a fungus with single conidiophores (439 to 656 [average 524] μm long × 6.2 to 11.6 [average 9.2] μm wide) with three to eight septa. Conidia were fusiform, obclavate to subcylindrical, straight or curved, and 30.4 to 180.1 (average 98.2) μm long × 6.7 to 18.1 (average 10.5) μm wide with 5 to 16 (commonly 13) distosepta. On the basis of morphological data and ITS rDNA sequences, the fungus was identified as Corynespora cassiicola (Berk. & Curt.) Wei. (1,2). Sequences of one isolate, EML-COR1, were more than 99% identical to sequences of C. cassiicola ATCC64204 (GenBank Accession No. AY238606) and C. cassiicola (GenBank Accession No. EF490450). In pathogenicity tests, the stems and leaves of two 2-month-old wounded and nonwounded potted plants (cv. Manchu) were sprayed until runoff with a conidial suspension of 5 × 10⁴ conidia per ml. The plants were maintained for 48 h in a humid chamber and then moved to a greenhouse. Symptoms similar to those observed in the commercial greenhouse developed on wounded stems within 10 days. On nonwounded plants, symptoms developed 3 to 4 weeks after inoculation. C. cassiicola was reisolated from these lesions. Control plants (sprayed with distilled water) remained symptomless. The experiment was repeated with similar results. Although C. cassiicola causes blight of cucumber (Cucumis sativus L.), sesame (Sesamum indicum L.), and other crops, to our knowledge, this is the first report of C. cassiicola on perilla. References: (1) M. B. Ellis. Page 372 in: Dematiaceous Hyphomycetes. 1971. (2) J. L. D. Silva et al. Plant Pathol. 55:580, 2006.