• Korean Journal Plant Pathology
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• v.1 no.2
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• pp.115-121
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• 1985

To improve methods of screening rice cultivars with field resistance to bacterial leaf blight, testing plant inoculation and neighbor plant inoculation were compared by using 33 rice cultivars. In the testing plant inoculation method, field resistance was evaluated by measuring the leaf areas diseased on the new leaves expanded after the inoculation. Varietal differences in field resistance were recognized more clearly by the testing plant inoculation method than by the neighbor plant inoculation method. Highly significant correlation was observed between the results of the two methods. Some rice cultivars such as, Seomjin, Hangangchal, Taebaeg, Samgang, Milyang 42, Asominori, Java 14, Chugoku 45 and 70X-46 showed remarkable field resistance to bacterial leaf blight. The testing plant inoculation method appeared desirable for screening rice cultivars for the qualitative and field resistance to bacterial leaf blight because of using less labor and less field area than neighbor plant inoculation.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.567-570
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• 1998

More than 100 isolates of Stemphylium obtained form leaf blight lesions of garlic (Allium sativum), onion (A. cepa) and leek (A. fistulosum) were identified as Stemphylium vesicarium (Wallr.) Simm. based on various morphological characteristics rather than S. botryosum Wallr. previously reported on those plants in Korea. In controlled inoculations, the pathogen induced the disease symptoms on leaves of garlic 7 days after inoculation. Onion and leek were also artificially infected by the fungus. This is the first report of S. vesicarium causing a leaf blight of garlic, onion and leek in Korea.

• Mycobiology
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• v.48 no.1
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• pp.70-74
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• 2020

Sinowilsonia henryi is a rare and endangered plant, as well as an endemic species in China. In July 2018, leaf spot and blight disease was observed on S. henryi in Yichang, Hubei, China. A fungus isolated from disease tissues was identified as Gonatobotryum apiculatum based on morphology and sequence analyses of ITS and LSU regions. Phylogenetic analyses indicated that the species belongs to Dothioraceae (Dothideales). Morphologically, the species produced two distinct types of conidia from authentic media, both conidia were described here. Pathogenicity tests showed that the fungus is a pathogen causing leaf spots on S. henryi. This is the first report of leaf spot and blight disease on S. henryi caused by G. apiculatum in China.

• The Plant Pathology Journal
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• v.16 no.5
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• pp.280-282
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• 2000

A leaf spot disease occurred on Allium tuberosum Roth. (Chinese chive) in Korea. All the isolates of Stemphylium sp. from the lesions of the diseased plant parts were identified as S. vesicarium (Waller.) Simmons, based on the morphological characteristics of conidia and conidiophores. Pathogenicity of the fungus was proved by artificial inoculation on Chinese chive plants. This is the first record of leaf blight on Chinese chive caused by S. vesicarium in Korea.

• The Plant Pathology Journal
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• v.38 no.5
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• pp.490-502
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• 2022

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial leaf blight (BLB) disease in rice (Oryza sativa L.) and it is among the most destructive pathogen responsible for severe yield losses. Potential bacterial biocontrol agents (BCAs) with plant growth promotion (PGP) abilities can be applied to better manage the BLB disease and increase crop yield, compared to current conventional practices. Thus, this study aimed to isolate, screen, and identify potential BCAs with PGP abilities. Isolation of the BCAs was performed from internal plant tissues and rhizosphere soil of healthy and Xoo-infected rice. A total of 18 bacterial strains were successfully screened for in vitro antagonistic ability against Xoo, siderophore production and PGP potentials. Among the bacterial strains, 3 endophytes, Bacillus sp. strain USML8, Bacillus sp. strain USML9, and Bacillus sp. strain USMR1 which were isolated from diseased plants harbored the BCA traits and significantly reduced leaf blight severity of rice. Simultaneously, the endophytic BCAs also possessed plant growth promoting traits and were able to enhance rice growth. Application of the selected endophytes (BCAs-PGP) at the early growth stage of rice exhibited potential in suppressing BLB disease and promoting rice growth.

• The Plant Pathology Journal
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• v.20 no.3
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• pp.192-195
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• 2004

A survey on ornamental diseases in 2000 and 2001 showed frequent occurrence of blight symptoms on leaves and stems of columbine and bleeding heart in botanical gardens of Gangwon and Chungnam provinces in Korea. A total of 65 isolates of Streptobotrys sp. were obtained from the infected leaves and stems of the two plants. All isolates were identified as Streptobotrys caulophylli based on their morphological and cultural characteristics. Blight symptoms were induced on leaves of the two plants by artificial inoculation with the isolates. This is the first report that S. caulophylli causes leaf and stem blight on columbine and bleeding heart in the world.

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.199-202
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• 1980

In order to investigate the relationship among the occurrence of bacterial leaf blight, amount of nitrogen application and planting density, a field experiment was carried out with factorial combinations of N levels (7.5, 15, 30kg/10a) and planting densities (10\times20,\;15\times30,\;20\times40cm). The results obtained in this study were; (1) The incidence of bacterial leaf blight was increased with increase of nitrogen application; (2) In double amount of nitrogen application (30kg/10a), the incidence of bacterial leaf blight was higher, regardless of planting density; (3) The incidence of bacterial leaf blight in Standard nitrogen application was significantly higher $(R=0.94^{**})$ than at $15\times30cm$ density and $20\times40cm$ planting density.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.40-44
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• 1981

This study was conducted to identify the possibility of paddy weeds served as the host plant of bacterial leaf blight, using various bacterial groups and inoculation methods. The results obtained can be summarized as follows. 1. Alopecurns spp., Setaria viridis P. Beauv., and Leersia juponica Makino were identified the most susceptible to bacterial leaf blight, similar to Milyang 23 which was used as a susceptible check variety. The others such as Digitaria adscendens Hem., Eleusine indic aGaertin., Cyperns serotinus Rottb, Cyperns difformis L. showed slight infection but most of broadleaf weeds were resistant to bacterial leaf blight. 2. Weed species showing early susceptibility maintained their susceptibility throughout the growth stages. Group I of bacterial leaf blight was the most effective to develop infection symptom to weeds. 3. Pin and scissor inoculation methods were more effective mean for infection than spray method which was used without wound.

• The Plant Pathology Journal
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• v.17 no.5
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• pp.249-256
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• 2001

Xanthomonas axonopodis pv. glycines 8ra produces a bacteriocin called glycinecinA, which specifically inhibits the growth of bacteria belonging to Xanthomonas species. GlycinecinA was produced by culturing Escherichia coli DH5 containing biosynthetic genes for glycinecinA, and was tested for its control effect against X. vesicatoria on red pepper and X. oryzae pv. oryzae on rice. The bacteriocin activity was much higher in the cell extract than in the supernatant. It reached a maximum level at the stationary phase, ws maintained up to 2 months at room temperature and approximately 10 months at $4^{\circ}$. The optimum concentration of glycinecinA for the control in the greenhouse and in the field was 12,800 AU/ml. In this study, the activity of glycinecinA on rice and red pepper leaves continued for 7-8 days, during which the pathogen populations remained at low levels. Bacterial leaf spot of red pepper and bacterial leaf blight of rice were significantly reduced by the bacteriocin treatments. The control efficacy was as high as, or even higher than, the chemical treatment of copper hydroxide. These results suggest that the bacteriocin is a potential control agent for bacterial diseases.

• Research in Plant Disease
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• v.6 no.1
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• pp.6-9
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• 2000

Nine samples of soft rotten roots and blighted leaves of Ficus spp. plants were collected from the vinyl-houses in Taejeon, Seongnam, Suweon and Yangjae in 1988 and pathogenic bactea were isolated from them Results of the studies on morphological, cultural, physiologucal and pathological characteristics indicated that the bacteria from Ficus retusa were Pseudomonas cichorii, from Ficus retusa \`Golden leaf\` and Ficus benjamina were P.viridiflava. These are the first description of bacteria which caused the diseases on Ficus spp. in Korea. We proposed to name the disease of Ficus retusa by P. cichorii as \"bacterial root rot of Ficus retusa\" and Ficus retusa(Golden leaf) and Ficus benjamina by P. viridiflava as \"bacterial leaf blight of Ficus retusa (Golden leaf)\", \"bacterial blight of Ficus benjamina\", respectively.