• Journal of Korean Society of Forest Science
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• v.58 no.1
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• pp.54-59
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• 1982

Powdery mildew has been observed on the several clones of Populus euramericana, P. deltoides, P. deltoides ${\times}$ P. maximowiczii in the nurseries of Chuncheongan-do and Kangwoen-do forest Research Institute in mid-October 1982. Powdery mildew fungus of Populus spp. was identified as phyllactinia guttata(Waller. ex Fr.) $L{\acute{e}}v$ which was reported as the powdery mildew fungus of Populus tomentosa Carr. Powdery mildew of Populus spp. caused by this fungus has not previously been reported in Korea. When we surveyed the occurrence of powdery mildew disease the leaves of P. deltoides R-89 were severely attacked by this fungus.

• The Korean Journal of Mycology
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• v.27 no.2 s.89
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• pp.158-163
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• 1999

Powdery mildew diseases previously unrecorded in Korea were noticed on four species of ornamental trees. Field observations on each disease were described and the causal fungi were identified. Powdery mildew of Symplocos chinensis for. pilosa was found to occur mildly, especially on plants growing in shade. The causal fungus was identified as Microsphaera nomurae U. Braun. Cornus florida was found to be infected with Microsphaera pulchra Cooke & Peck and supposed to be epidemic in nursery. Powdery mildew of Malus baccata occurred on young leaves and herbaceous stems in nursery. The causal fungus was classified as Podosphaera leucotricha (Ellis & Everh.) Salmon. Powdery mildew of Ulmus macrocarpa was found to occur in autumn and severe on young shoots. Uncinula kenjiana Homma was identified as the causal fungus.

• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.234-236
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• 1999

Sphaerotheca fuliginea has previously been recorded as a powdery mildew fungus on dahlia (Dahlia pinnata) in Korea. Six collections of the dahlia mildew by the authors since 1993, however, show that the fungus does not contain conspicuous fibrosin bodies and has sinuate edge lines on conidiophores. These characters clearly indicate that the fungus causing the powdery mildew on dahlia in Korea is Erysiphe cichoracearum. On the other hand, one plant of dahlia grown in a pot was found to be infected with S. fusca (= S. fuliginea s. lat.). It is supposed to be unusual. Therefore, two species of dahlia mildew fungi are distributed and E. cichoracearum is the main cause of dahlia mildew in Korea.

• The Plant Pathology Journal
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• v.25 no.3
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• pp.299-301
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• 2009

Powdery mildew symptoms were frequently on plants of goat's-beard (Aruncus dioicus var. kamtschaticus) found cultivated in the island Ulleungdo in June 2008. The symptoms appeared as powdery mycelial colonies and dark brown cleistothecia on leaves, petioles, stems and budding flowers of the plant. Incidence of the disease was as high as 50-80% in the goat's-beard fields. Specimens of the diseased plants were collected and examined for morphological characteristics of the causal fungus. On the basis of morphological characteristics of the conidial stage and the teleomorph, the fungus was identified as Podosphaera ferruginea. This is the first report of goat's-beard powdery mildew caused by Podosphaera ferruginea in Korea.

• The Korean Journal of Mycology
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• v.50 no.3
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• pp.243-248
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• 2022

In Japan and China, Podosphaera pseudofusca causes powdery mildew in Fatoua villosa. During a taxonomic revision of Korean powdery mildew fungi, isolates newly collected from F. villosa were studied. Through morphological examination and molecular phylogenetic analyses of the internal transcribed spacer region and large subunit gene of rDNA, the powdery mildew fungus was identified as Podosphaera xanthii. In this study, we propose the merging of P. pseudofusca sensu Braun into the P. xanthii complex. To the best of our knowledge, this is the first report of Podosphaera powdery mildew on F. villosa in Korea.

• The Korean Journal of Mycology
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• v.51 no.4
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• pp.307-311
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• 2023

Powdery mildew anamorphs were collected from Orixa japonica (Rutaceae) in Korea. Based on the morphology and molecular phylogeny derived from the internal transcribed spacer regions and the large subunit gene of the rDNA, the fungus was identified as Erysiphe orixae. This powdery mildew species has been known to be endemic to Japan. This is the first report on E. orixae in Korea.

• Research in Plant Disease
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• v.17 no.3
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• pp.391-395
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• 2011

The presence of Pleochaeta shiraiana associated with powdery mildew of Celtis sinensis in Korea is dubious, mainly due to incomplete records of earlier workers. To confirm the occurrence of the powdery mildew and the identity of the causal fungus, morphological characteristics of the anamorph and teleomorph from nine samples deposited in KUS (Herbarium in Korea University) were examined by light microscopy. Identification of the fungus was supported by comparing four ITS sequences from Korean samples with two Japanese data. This is the first confirmed report of the powdery mildew associated with P. shiraiana in Korea.

• Korean Journal of Environmental Agriculture
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• v.17 no.4
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• pp.306-311
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• 1998

Effects of soluble silicon and surfactants on the development of powdery mildew of cucumber were tested for environmentally safe powdery mildew control. Tested soluble silicon was potassium silicate$(K_2SiO_3)$ and tested commercial surfactants were Jeonchakje, Silhouette, Kaba, and Tween 20. Tested concentrations were 2, 4, 8, 16mM for the soluble silicon, 0.5 and 1.0% for Tween 20, 0.05 and 0.1% for both Jeonchakje and Kaba, and 0.03 and 0.07% for Silhouette. Water dilutions of tested materials were sprayed on cucumber (Cucumis sativus) leaves once a week for 4 weeks. From 3 days after the second spray, the diseased area and the numbers of fungal colony were measured from the treated leaves for 6 times at 3-4 days interval. Powdery mildew was less severe on treated cucumber compared to distilled water-treated cucumber (check). In all treatments, diseased area index was proportional to the number of the fungal colony. At the end of investigation, there was severe powdery mildew on check cucumbers. Average 30% of a leaf was colonized by powdery mildew fungus and the average number of the fungal colony per leaf reached to more than 70. On the other hand, none of the treated cucumber suffered severe powdery mildew. The treatments including 8 and 16mM of soluble silicon, doubled concentration of Kaba, and 0.5 and 1.0% of Tween 20 showed more than 80% of control effect compared to water-treated cucumber. In addition, no phytotoxicity was found. Potassium silicate and Tween 20 showed the possibility to replace chemical pesticides for the control of powdery mildew.

• Mycobiology
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• v.28 no.1
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• pp.51-53
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• 2000

The powdery mildew of safflower (Carthamus tinctorius L.) extensively occurred at 1999 at the experimental farm of Kyongsangnam-do Agricultural Research and Extension Services. Both sides of the leaves and the older stems were covered with the fungus, and then the leaves and stems turned yellow. The conidia, conidiophores and perithecia were observed on the leaf lesion. Perithecia were ellipsoidal, $80-117\;{\mu}m$ in diameter. Asci were subglobose and $84{\sim}99{\times}59{\sim}73\;{\mu}m$ in size. Ascospore were ellipsoidal to ovoid, and $15{\sim}34{\times}11{\sim}23\;{\mu}m$ in size. Conidia were ellipsoid to barrel-shaped, $25{\sim}37{\times}11{\sim}22\;{\mu}m$ in size and formed in long chains. The causal organism was identified as Sphaerotheca fuliginea. This is the first report on powdery mildew of safflower caused by Sphaerotheca fuliginea in Korea.

• The Plant Pathology Journal
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• v.27 no.1
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• pp.85-88
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• 2011

Podosphaera fusca (syn. Sphaerotheca fusca, S. fuliginea) is a causal agent of powdery mildew infections on Zinnia elegans, and has been documented in Korea since 1967. An outbreak involving about 1,000 plants in October 2008, in Yangpyeong, Korea, was caused by Golovinomyces cichoracearum. Further surveys of zinnia powdery mildew from 2008-2010 confirmed the widespread occurrence of Zinnia-Golovinomyces association in Korea. Chasmothecia of this fungus have not been found on Z. elegans in Korea. Analysis of internal transcribed spacer rDNA from five Korean collections confirmed the powdery mildew as G. cichoracearum. Comparison with the those from GenBank revealed 100% identity with sequences from zinnia powdery mildew, forming a monophyletic clade with 100% bootstrap support, and with those of G. cichoracearum parasitic on the hosts belonging to the tribe Heliantheae of the family Asteraceae.