• Research in Plant Disease
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• v.14 no.3
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• pp.214-218
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• 2008

Coleosporium neocacaliae, a needle rust fungus, was described and illustrated for the first time on the needles of Pinus koraiensis (Korean pine) in Korea. Detailed descriptions of the species were verified based on symptoms and signs, and light and scanning electron microscopic observations on aecia, aeciospores and peridial cells. The present needle rust fungus was apparently different from C. eupatorii, a solely recorded Coleosporium species on P. Koraiensis in Korea until this time, in having comparatively large sized aeciospores as $20-39{\times}14-27\;{\mu}m$ than those of latter species (size of aeciospores $15-27{\times}10-20\;{\mu}m$). Verrucose surface structure of aeciospores in light microscopy was revealed to be annulated with three to four rings and root-like base in scanning electron microscopy. Aecial stage of C. neocacaliae were formed on the middle days of April to the early days of June and collected around the central parts of Korean peninsula, including high mountains of about 1,000 m above sea level.

• Mycobiology
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• v.43 no.3
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• pp.351-353
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• 2015

Farfugium japonicum is used in traditional medicine and as an edible herb in China and Korea. In July 2013, leaf spots were observed in F. japonicum seedlings at Ulleung Island, Gyeongsangbuk Province, Korea. Early symptoms on the leaf adaxial surface included roughly circular yellow spots that later developed brown, necrotic centers. The aecia were hypophyllous, cupulate, yellowish, $180{\sim}430{\mu}m$ in diameter, clustered, and erumpent with a peridium with a recurved margin. The aeciospores were globoid, $14{\sim}17{\times}13{\sim}16{\mu}m$, light yellow or colorless, and densely verrucose. The 28S rDNA sequence of the isolate was identical to each other and shared 99% identity with Puccinia caricis. This is the first report of rust caused by P. caricis in F. japonicum in Korea or elsewhere in the world.

• Research in Plant Disease
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• v.29 no.3
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• pp.299-303
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• 2023

Rust symptoms on Meliosma myriantha trees have been noticed during disease surveys in Korea since 2010, with a high disease incidence frequently surpassing 90%. The causal fungus of the rust disease was identified as Neophysopella vitis based on the morphological investigation and molecular sequence analysis of the internal transcribed spacer (ITS) and large subunit (LSU) rDNA regions. This is the first report of rust disease caused by N. vitis on M. myriantha in Korea. A pathogenicity assay proved that M. myriantha serves as the aecial host of N. vitis as spermogonia and aeciospores were produced, which can infect the two uredinial hosts, Boston ivy (Parthenocissus tricuspidata) and Virginia creeper (Parthenocissus quinquefolia).

• The Korean Journal of Mycology
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• v.44 no.4
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• pp.377-381
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• 2016

Abnormal chloranthy was observed on Prunus mume trees grown in an orchard in Uiseong, Gyeongbuk province, Korea in 2015. Flower buds showing chloranthy were covered with numerous orange-colored sori, which were confirmed to contain spermogonia and aeciospores by stereo microscopy and light microscopy. When observed using scanning electron microscope, the aeciospores were globose, ellipsoid, or ovoid, and measured $22.8{\sim}35.6{\times}19.8{\sim}36.8{\mu}m$, with a verrucae wall ornamentation. To construct a phylogeny, the large and small subunit regions of rDNA were sequenced and compared with those of allied species by the maximum likelihood method. The isolated fungus species showed high similarities with Caeoma makinoi (Teleomorph: Blastospora smilacis), which was previously isolated from P. mume in Japan. Therefore, we initially report this fungal agent parasitic on P. mume as C. makinoi in Korea and name the disease it causes as "flower bud chloranthy disease".

• Research in Plant Disease
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• v.21 no.3
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• pp.250-252
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• 2015

The tejocote (Crataegus spp.) is a tree considered to be native to Mexico. The aim of this study was to identify the causal agent of tejocote rust in the State of Puebla. Tejocote fruits were sampled in 2012 and 2013. The fungus was studied morphologically using light and scanning electron microscopy and molecularly using phylogenetic analysis of 18S and 28S rDNA genes. The fungus was identified as Gymnosporangium clavipes on tejocote fruits. To our knowledge, this is the first confirmed report of Gymnosporangium clavipes Cooke & Peck affecting Crataegus mexicana var. Chapeado and C. gracilior in Puebla Mexico.

• Research in Plant Disease
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• v.10 no.4
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• pp.279-284
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• 2004

A rust fungus has caused a serious early defoliation of Zanthoxylum schinifolium during growing seasons every year at the plantations located at Hadong and Jinju, Kyeongsangnam-Do in Korea. In order to identify the rust fungus and clarify its life cycle in Korea, aeciospores from Pinus thunbergii were artificially inoculated on the leaves of Z. schinifolium. Uredinial stage was successively formed on the leaves of Z. schinifolium. Based on the artificial inoculation test and on the morphological features of the dried specimens collected from P. thunbergii and Z. schinifolium, this rust fungus was identified as Coleosporium xanthoxyli. Morphological features of aecial and uredinial stages of the species were described. The first symptom of the infection was developed from later June to early July. And leaf infection ratio was 17.8%-58.7% during August at Hadong and Jinju regions of Kyeongsangnam-Do in Korea.

• Research in Plant Disease
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• v.26 no.1
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• pp.53-56
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• 2020

Red spots symptoms were observed on the leaves of Rumex japonicus Houtt. in Goesan, Korea, in May 2019. Diseased leaf showing red spot and white-colored sori were found behind of diseased leaves. Aeciospores were confirmed and observed using a stereomicroscope, light microscope, and scanning electron microscope. They were globose or ovoid and measured 19.0-24.4×19.0-24.5 ㎛, with verrucae ornamentation. For the phylogenetic analysis, partial of large subunit rDNA region and cytochrome c oxidase subunit III were sequenced. As a result, the isolated fungus species showed high similarities with Puccinia prizeliana. Based on the previous report, morphological characters, phylogenetic analysis, it was confirmed as Puccinia phragmitis which have not been reported in Korea, and we firstly report this fungal agent on R. japonicus as P. phragmitis in Korea.

• The Plant Pathology Journal
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• v.23 no.1
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• pp.7-12
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• 2007

Perilla rust is a damaging disease in perilla cultivation in Korea. Its causal agent was identified as Coleosporium plectranthi based on descriptions of morphological characteristics of spores and spore-producing fruiting structures(in uredinial and telial stages from perilla and in aecial stage from the alternate host pine) collected in 15 locations in Korea during the disease survey from 2004 to 2006. These characteristics were yellow or orange uredinium; globose or ellipsoid urediniospore of $20.8{\mu}m{\times}18{\mu}m$ in size; verruca of $0.3mm{\times}1.2mm$; orange telium; one-celled, oblong ellipsoid teliospore of $63.1{\mu}m{\times}19.7{\mu}m$ with one-layered crusts or four-celled(when mature), internal basidium of $64.2{\mu}m{\times}19.7{\mu}m$; ellipsoid to globoid basidiospore of $20.3{\mu}m{\times}12{\mu}m$; type 2 spermogonium; yellow, broadly ellipsoid peridial cell of $35.6{\mu}m{\times}23.1{\mu}m$; and broadly ellipsoidal or subglobose aeciospore of $25.9{\mu}m{\times}18.8{\mu}m$. Phylogenetic analysis of 28S rDNA sequences revealed the closest relatedness to those of the genus Coleosporium, a monophyletic group distinguished from other rust fungi and divided into two main lineages, one of which was C. plectranthi grouped with high bootstrap value(96%). In pathogenicity test, both aeciospores and urediniospores caused rust development on perilla leaves. This is the first description of C. plectranthi causing perilla rust with the first findings of its telial stage on perilla and the first rust disease on the aecial host in Pinus densiflora. These aspects would provide basic information for the development of control measures of the disease.

• Journal of Korean Society of Forest Science
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• v.62 no.1
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• pp.76-81
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• 1983

Pedicularis spp. are the alternate hosts of the white pine blister rust fungi in the forests of Korea, and Ribes spp. were found as other alternate hosts by artificial inoculation test. New biotypes (races) with different host selectivity and pathogenicity of the causal fungi were speculated at various places in Korea. The aeciospores of the fungi were collected from two isolated places, Pyeongchang and Namwoen, and artificially inoculated on Pedicularis resupinata and six species of the genus Ribes. Among the tested alternate host species, P. resupinata and R. montigenum were only susceptible to both the Pyeongchang population and the Namwoen population, showing similar pathogencity between the two fungai populations. Three white pine species were planted in fungus-infested stands to study the susceptibility of each tree species. Four years later, 17.7% of Pinus koraiensis and 26.3% of the P. strobus were infected, but P. parviflora was free from attack. From the above results, it was concluded that the white pine blister rust fungus populations in Korea are of the same biotype, with P. koraiensis and P. strobus as aecial hosts, and Pedicularis spp. and Ribes spp. as telial hosts.