• The Korean Journal of Mycology
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• v.12 no.4
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• pp.159-163
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• 1984

Sphaerotheca fuliginea (Schlecht. ex Fr.) Poll. has been recorded on 13 plant species in Korea, to which the authors add 10 additional host plants. The taxonomic concept of S. fuliginea proposed by Blumer in 1933 was adopted here.

• 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 Korean Journal of Mycology
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• v.29 no.2
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• pp.116-122
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• 2001

An isolate of the prospective hyperparasite, Ampelomyces quisqualis 94013 (AQ94013) was selected for the use of biological control of cucumber powdery mildew caused by Sphaerotheca fuliginea. Examination for the parasitism processes by scanning electron microscopy and light microscopy showed that conidia of AQ49013 germinated on conidia, conidiophores and hyphae of Sphaerotheca fuliginea four hours after inoculation. Appressorium-like structures were developed and attached to the hyphae of S. fuliginea seventeen hours after inoculation. Hyphae of AQ94013 penetrated into hyphae of S. fuliginea twenty-four hours after inoculation. Pycnidia of AQ94013 were produced in the hyphae and the basal part of conidiophores of S. fuliginea fourty four hours after inoculation. The pycnidia of AQ94013 matured foully eight hours after inoculation, and the conidia were discharged from the ostioles of the pycnidia fifty two hours after the inoculation. At the same time, hyphae and conidiophores of S. fuliginea were distorted and died. Also, concentrated culture filtrate and culture filtrate of AQ94013 had not suppressed the cucumber powdery mildew fungus as water treatment. Therefore, mode of action of AQ94013 was assumed to be parasitism on powdery mildew fungi.

• 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.27 no.1
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• pp.8-13
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• 2011

The induced resistance of cucumber leaves treated with oligochitosan to the infection of the cucumber powdery mildew, Sphaerotheca fuliginea, was investigated using transmission electron microscopy. The results showed that when the plants were treated with oligochitosan and challenged with inoculum, a significant decrease of the disease occurred. The mycelial development in the treated leaves was markedly inhibited. The cytoplasm of the powdery mildew mycelium was aggregated, with its organelles disintegrated and the cytoplasm collapsed. The protoplasm in haustoria became electron-dense. Haustoria became malformed, their organelles disintegrated, the hausterial wall thickened and eventually the whole complex necrotized. The host cells produced defence structures and materials associated with infection and a hypersensitive response. The host cell wall was thickened and deeply stained; several layers of papilla structure were produced under the cell wall; dark materials were deposited between the cell wall and plasmalemma; extrahaustorial plasmalemma was deeply stained and extrahaustorial matrix appositions had large deposits of electron-dense material; the cytoplasm was disordered, host organelles disintegrated and eventually the whole host cell disintegrated and necrotized.

• Korean Journal of Microbiology
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• v.5 no.1
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• pp.24-33
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• 1967

Fifty-two specimens of the infected plants were collected from areas through the country during the year of 1965. We report here 14 unrecorded specoes which were identified in this work. The results are as follows: 1. Erysiphe cichoracearum DC. (Host: Artemisia princeps PAMPAN. var. orien-talls HARA.) 2. Erysiphe cichoracearum DC. (Host: Plantago sp.) 3. Erysiphe cichoracearum DC. (Host: Sonchus oleraceus L.) 4. Erysiphe pisi DE CANDOLLE. (Host: Lespedeza sp.) 5. Erysiphe polygoni DE CANDOLLE. (Host: Clematis patens MORR et DECAIS.) 6. Microsphaera alphitoides GRIFFITHS et MAUBLANCE (Uncinula bifurcata GERARD.) (Host: Quercus serrate GERARD) 7. Microsphaera baumleri MAGNUS. (Host: Robinia pseud-acacia L.) 8. Microsphaera coryli HOMMA. (Host: Corylus heterophylla FISCH. var. japonica KOIDZUMI) 9. Podosphaera tridactyla (WALLROTH) DE BARY. (Host: Prunus leveilleana KOEHN. var. typica NAKAI) 10. Sphaerotheca fuliginea (SCHLECHTENDAHL) POLLACI. (Host: Impatiens balsamina L.) 11. Sphaerotheca fuliginea (SCHLECHTENDAHL) POLLACI. (Host: Zinnia elegans JACQ) 12. Uncinula aceris SACCARDO (Host: Acer negundo L.) 13. Uncinula fraxini MIYABE(U. salmon SYDOW) (Host: Fraxinus rhynchophyllus HANCE.) 14. Uncinula salicis (DE CANDOLLE) WINTER. (Host: Salix gracilistyla MIQ.)

• Research in Plant Disease
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• v.16 no.3
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• pp.285-289
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• 2010

The experiments were carried out in fields for two years from 2008 to assess yield losses of squash due to powdery mildew caused by Sphaerotheca fuliginea and to determine its economic thresholds. Powdery mildew disease was first observed in late June, about 50 days after field-transplanting, progressed rapidly during late July to early August, and began to reduce from late August. Powdery mildew severity was negatively correlated with squash yields. A positive correlation was observed between fruit weight and % marketable fruits. A simple linear regression model was obtained as Y=-10.399 X + 6607.5 with $R^2$ = 0.9700 when squash yields (Y) was predicted using powdery mildew severity as an independent variable(X). Spray threshold for maximizing squash yields without economic considerations was estimated as 6.5% in terms of leaf lesion area with powdery mildew. Economic threshold and economic spray threshold able to compensate the costs of fungicide sprays were determined as 21.6% and 17.3% in leaf lesion area, respectively.

• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.307-312
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• 1989

Strain No.77-AG-567 showed antifungal activity against Pyricularia oryzas and Sphaerotheca fuliginea. In the process of purification of active component this strain was found to produce blasticidin S together with another antibiotic. This compound was identified as being acetoxycyc-heximide, also referred to as E-73, by UV and $^1$H NMR spectral data. Identification of this strain led us to conclude that strain No.77-AG-567 is most probably be Streptomyces atratus. It showed different characteristics from S. atbutus, so far known to produce both blasticidin S and acetoxycycloheximide. Particularly worthy of note was the difference in spore surface. In addition, acetoxycycloheximide has been known to have activity only against yeast and tumor cells but we found that it also has activity against Pyricularia oryzae and Sphasrotheca fuliginea.

• Korean Journal of Microbiology
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• v.7 no.1
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• pp.22-28
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• 1969

Twenty-nine specimens of the infected plans were collected from areas through the country since 1967 to 1968. We report here four unrecorded causla organisms of powdery and their hosts which were identified in this work. The results as as follows : 1. Microsphaera diffusa Cooke et Peck (M.magnoliae Sawoda) (Host:Magnolia obovata Thunb.) 2. Sphaerotheca humili (de Condolle0Burill. (Host: Spirea sp.) 3. Phyllactinea fraxini (de Condolle)Homma. (Host : Betuls sp.) 4. Uncinula sengorui.Salmon.(Host : Celastrus orbiculatus, Thunb.) * Six unrecorded host 1. Altemisia japonica. Thunb. (Pathogen : Erysiohe cichoracearum DC.) 2. Aster tataricus. L. (Pathogen :Sohaerotheca fuliginea (Schlechtendahl) Poll. 3. Dohlia variabilis Defont. (Pathogen :Sphaerotheeca fuliginea (schlechtendahl) poll. 5. Helianthus ammues (Pathogen :Spherotheca fuliginea schlechtendahl) poll. 6. Solanum melangera L. (Pathogen : Erysiphe cichoracearum DC.)

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.04a
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• pp.41.1-41
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• 1999