• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.237-244
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• 1996

길항곰팡이 3종(Aspergillus sp. A101, Penicillium sp. B202, Trichoderma sp. C303), 길항세균 3종(Arthrobacter sp. AN303)또는 이들 모두의 혼합균주를 배양하여 creeping bentgrass 양묘장에 처리하여 Pythium blight, brown patch 및 dollar spot의 방제효과를 조사하였다. 또한 길항미생물 6종의 배양액을 살균제와 병용하여 그린에 살포하여 이들 토양병에 대한 방제효과를 조사하였다. 양묘장에서는 미생물의 종류에 관계없이 Pythium blight 억제효과가 커 3회 이상 미생물제 처리시 병이 전혀 발생하지 않았다. 그러나 brown patch와 dollar spot은 미생물제에 의한 방제효과가 크지 않았으며, 살균제에 의해 효과적으로 방제되었다. 미생물제와 살균(Pythium blight 방제용 살균제 제외)를 병용하여 처리한 그린에서는 살균제 단독처리와 비교할 때 brown patch는 유의적으로 억제되었고 Pythium blight와 dollar spot은 차이가 없었다.

• Plant Disease and Agriculture
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• v.1 no.1
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• pp.19-29
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• 1995

A microbial product composed of three antagonistic fungal isolates (Aspergillus sp., Penicillium sp. and Trichoderma sp.) and three bacterial isolates (Arthrobacter sp., Bacillus sp., and Pseudomonas sp.) was tested for the control of Pythium blight caused by Pythium sp., brown patch by Rhizoctonia solani (anastomosis group(AG) 1-1) and large patch by R. solani (AG 2-2) of turfgrasses. Cultures of the antagonistic fungi and bacteria varied in the effectiveness in reducing disease severity of Pytium blight and brown patch on bentgrass. The antagonistic fungal and bacterial isolates were mixed and cultured at 20-$25^{\circ}C$ for 3 days in a growth medium, and the diluted solution of the microbial culture was applied under the field conditions after inoculation of the above turfgrass pathogens. The treated turfgrass was incubated at 28$^{\circ}C$ in a growth chamber. In this experiment, Pythium blight was almost completely controlled and brown patch was slightly decreased by the microbial product, while no control was observed in large patch of zoysiagrass. In zoysiagrass treated with the microbial culture, thatch accumulation was notably reduced.

• The Plant Pathology Journal
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• v.17 no.1
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• pp.40-44
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• 2001

Disease occurrence and development of gray blight of tea (Camellia sinensis) were investigated. Higher incidences and more severe damage by gray blight were found in Japanese tea variety Yabukita than the Korean local variety. In Yabukita, Pestalotiopsis longiseta was more frequently observed on the diseased leaves than P. theae but vice versa in the Korean local variety. This indicates that there was the varietal difference in the distribution of fungal species of gray blight pathogens. Both varieties were most severely damaged during the third harvest period with weather conditions of high temperature and humidity favorable to the disease. Presence of the tea brown blight fungus Glomerella cingulata on the margin of gray blight lesion at the late stahe suggested that the pathogenic fungi of tea gray blight were replaced by the brown blight fungus during the disease development.

• Korean Journal Plant Pathology
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• v.14 no.4
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• pp.287-293
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• 1998

Bipolaris coicis, B. cynodontis, B. maydis and Curvularia lunata were leaf blight fungi detected from 45 seed samples of Job's tears and B. coicis was the predominant species in seed samples followed by C. lunata, B. cynodontis and B. maydis. When the seed components were plated on test tube agar, B. coicis and C. lunata were highly detected from invelucre, glume, endosperm and stamen, but not detected from plumule. Seed infection with B. coicis casued seed rot, coleoptile blight and seedling blight of Job's tears. Conidial characteristics of leaf blight fungi were as follows; B. cynodontis was fusiform, brown, slightly curved, 0~5 distoseptate, and 16.8-48$\times$7.2-16.8${\mu}{\textrm}{m}$ in size; B. cynodontis was fusiform, brown, slightly curved, 0~8 distoseptate, and 16.8-72$\times$9.6-19.2 ${\mu}{\textrm}{m}$; B. maydis was fusiform, brown, distintly curved, 0~10 distoseptate, and 28.8-110.4$\times$12-21.6 ${\mu}{\textrm}{m}$. C. Lunata was fusiform, brown, typically curved, 0~3 distoseptate, and 7.2-24$\times$4.8-12 ${\mu}{\textrm}{m}$. B. coicis was highly pathogenic to Job's tears and corn, weakly pathogenic to rice, but not pathogenic to wheat and barley. c. lunata was highly pathogenic to Job's tears (No. 2), corn, wheat and barley, weakly pathogenic to Job's tears (No. 1), but not pathogenic to rice. All treatments were effective to inhibition of leaf blight fungi when carboram, benoram, fludioxonil, prochloraz, thioram, and tap water treated to infected seeds.

• Mycobiology
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• v.38 no.4
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• pp.316-320
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• 2010

Leaf spot and blight disease was observed on two-year-old seedlings of Dendropanax morbifera (Korean name: Hwangchil tree) during July of 2008 in Jindo Island, Korea. Symptoms included yellow-brown to dark brown irregularly enlarged spots frequently located along the veins of leaves. The lesions were often surrounded by chlorotic haloes. Severe leaf blight and subsequent defoliation occurred when conditions favored disease outbreak. The causal organism of the disease was identified as Alternaria panax based on morphological characteristics and sequence analysis of the internal transcribed spacer region of rDNA. A. panax isolates induced leaf spots and blight symptoms not only on D. morbifera but also on the other members of Araliaceae tested. This is the first report of foliar blight caused by A. panax on D. morbifera.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.348-351
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• 2001

This study was conducted to evaluate the control effect of fungicides on control of brown leaf blight, growth characteristics, and dry root yield in the cultivation of Alisma plantago after early maturing rice cropping. All fungicides treated had no effect on the growth and flowering rate of Alisma plantago. The major fungicides were mancozeb Wp, 75%, chlorothalonil Wp, 75%, dithianon Wp, 43%, difenoconazole Wp, 10%, benomyl Wp, 50%, and propineb Wp, 70%. Dry root of yield were increased largely with chlorothalonil Wp, 75%(33 g/20), fungicide than the other fungicides and control. All fungicides had no injury with standard dosage. On the other hand all fungicides had slight injury in the double dosage level for the Alisma plantago.

• Research in Plant Disease
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• v.9 no.4
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• pp.213-216
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• 2003

A bacterial disease of tea plants(Camellia sinensis L.) was found in the graftage nursery grown under vinyl house conditions in Suncheon city, Korea, in spring of 2002. The primary symptoms of the disease include small, water-soaked and dark brown spot development on the young leaves. This spot gradually increases in size, especially taking on elongate shape along the midrib or vein of the leaf, and then turns black. The diseased leaves were defoliated easily. Ten strains were isolated from the infected leaf. Inoculation on tea leaf with these isolates produced the same symptoms of naturally infected plants. On the basis of stain reactions, morphological characterization, colony pattern, physiological and biochemical reactions, the bacterium was identified as Pseudomonas syringae pv. theae. This is the first report of brown blight of tea plant in Korea.

• Research in Plant Disease
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• v.30 no.1
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• pp.82-87
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• 2024

Leatherleaf fern (Rumohra adiantiformis) is an important ornamental plant in Indonesia and global. Green fern leaves with bold dark green color with long shelf-life, attract florists as decoration. Indonesia is one important leatherleaf fern exporters, however currently an outbreak of leaf blight decreased production significantly. Initial symptom was reddish brown spots from edge of leaf, which was gradually followed by dark-brown necrotic lesions causing leaf blight and dried. This is a study to do Koch-Postulate approach and molecular identification, to identify the pathogen of the "new emerging disease" reported. Based on multigene analysis using primers from ITS, β-tub and tef1-α gene markers, the pathogen was identified as Neopestalotiopsis sp. All sequences have been deposited in GenBank with accession number of OR905551 (ITS), OR899817 (ßtubulin) and OR899816 (TEF). This Neopestalotiopsis leaf blight causes an emerging concern in leatherleaf fern in Indonesia and global biosecurity because it infected an export commodity.

• Research in Plant Disease
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• v.7 no.2
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• pp.112-115
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• 2001

Blossom blight of petunia caused by Choanephora cucurbitarum was found in greenhouses around Jinju area, Gyeongnam province, Korea in April 2001. The disease started with water-soaked lesions on the flower which rapidly withered and was rotten. Calyces developed water-soaked, dark-green lesions, and then were rotten. Whitish mycelia and monosporous sporangiola were produced on the lesions. The fungus isolated from the lesions produced white to pale yellowish brown mycelia with scattered monosporous sporangiola on potato-dextrose agar (PDA) plates. Size of sporangium was 37.2~135.8 um. Monosporous sporangiola were elliptic, fusiform or ovoid, and brown in color and their size was 10.4~22.4$\times$7.4~12.9 um. Sporangiospores were elliptic, fusiform or ovoid in shape, dark brown or brown in color and were 13.7~23.5$\times$8.7~13.8 um in size, and had appendaged appressorium of 3 or more. Zygospores were black, and 40.8~61.5 um in size. The fungus grew on PDA at 15-4$0^{\circ}C$, and optimum temperature was 3$0^{\circ}C$. This is the first report on the blossom blight of petunia caused by C. cucurbitarum in Korea.

• The Plant Pathology Journal
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• v.21 no.4
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• pp.328-333
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• 2005

Paenibacillus elgii SD17 (KCTC $10016BP^T$=NBRC $100335^T$) was recently reported as a new species. Based on its inhibitory activity to Thanatephorus cucumeris AG1-1, strain SD17 was further evaluated for its potential as a biocontrol agent against soil-borne diseases of turf grasses in Korea. P. elgii SD17 showed a broad spectrum of antimicrobial activity in vitro test and suppressed development of turf grass diseases; Pythium blight caused by Pythium aphanidermatum and brown patch caused by T. cucumeris AG1-1 on creeping bentgrass (Agrostis palustris) in the growth chamber tests. Under a condition for massive culture in a 5,000 L fermenter, P. elgii SD17 reached $6.4{\times}10^8$ spores/ml that resulted in approximately $1.0{\times}10^7$ cfu/g when formulated into a granule formulation (GR) using the whole culture broth instead of water. Using the GR formulation, biocontrol activity of P. elgii SD17 was confirmed. In the growth chamber tests, the GR formulation was effective against brown patch and Pythium blight with similar level of disease severity compared to each of the standard fungicides at the application rates of 10 g/$m^2$ or above. In the field tests, compared to each untreated control, the GR formulation also effectively controlled Pythium blight, brown patch and large patch at all the application rates of 5, 10 and 20 g/$m^2$, respectively, without significant response by the application rates. However its performance was inferior to each of the standard chemical fungicides. Based on these results, we consider this GR formulation of P. elgii SD17 as an effective biocontol agent to suppress Pythium blight, brown patch and large patch of turf grasses in Korea.