• 한국식물병리학회지
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• 제14권6호
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• pp.661-663
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• 1998

Bipolaris stem rot of cactus severely occurred up to 77% at the field of Koyang and Kimcheon from 1996 to 1997. The symptom was initially light yellow, water soaked round lesion, subsequently turned light brown and dried to death. The causal fungus was identified as Bipolaris cactivora (Petrak) Alcorn. Conidia were obclavate to fusoid, rounded ends, light brown color, 1~4 septate, and conidial size was 23~42$\times$6~9 ${\mu}{\textrm}{m}$ (av. 32.5$\times$7.5 ${\mu}{\textrm}{m}$). Conidiophores were caespitose, straight, pale to golden brown and 67~280 ${\mu}{\textrm}{m}$ in length. When healthy cacti were inoculated with the isolates obtained form the lesion of diseased plants, the same characteristic symptoms as those in the field were produced. The symptom of four-month-old cactus was developed more rapidly than that of six-month-old cactus. The pathogen was reisolated from the artificially inoculated lesions.

• 분석과학
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• 제9권1호
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• pp.107-111
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• 1996

Bipolaris cynodontis의 배양 추출물로부터 이탈리안 라이그라스 뿌리의 생육저해 활성을 나타내는 물질을 분리 정제한 다음에 2차원 NMR을 포함한 각종 기기분석을 이용하여 구조를 결정하였다. 이 화합물의 분자식은 $C_{24}H_{30}O_5$ 이었으며 세스퀴테르펜류 화합물로 이탈리안 라이그라스 및 벼와 같은 벼과식물에 대해서 100ppm에서 100%의 활성을 나타내는 것으로 보아 병원균의 병징 발현에 관여하는 것으로 보여진다.

• 한국균학회지
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• 제29권2호
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• pp.110-115
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• 2001

1998년 화본과 작물, 목초, 잔디 및 야생잡초의 잎점무늬와 잎마름 증상으로부터 분리한 66균주에서 Bipolaris 9종, Drechslera 2종 및 Exserohilum 2종을 동정하였다. 동정결과 Bipolaris bicolor, B. coicis, B. cynodontis, B. maydis, B. oryzae, B. panici-miliacei, B. setarial, B. sorghicola, B. sorokiniana, Drechslera dictyoides, D. graminea, Exserohilum oryzicola 및 F. turicum이 분리되었다. 분생포자와 분생자경의 균학적 특징은 자연적 기질과 물한천배지에서 관찰하였다. 그 중에서 B. bicolor, B. sorghicola, D. dictyoides 및 E. oryzicola 4종과 기주식물 12종을 국내에서 처음 보고한다.

• 분석과학
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• 제9권1호
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• pp.112-117
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• 1996

이탈리안 라이그라스(Lolium multiflorum Lam.) 및 버뮤다그라스와 같은 벼과 잡초에 병해를 일으키는 Bipolaris cynodontis의 배양 추출물로부터 이탈리안 라이그라스 뿌리의 생육저해를 나타내는 3종류의 활성물질을 분리 정제하고 $^1H$, $^{13}C$ 및 2차원 NMR을 포함한 각종 기기분석방법을 통하여 이들 화함물들의 구조를 결정하였다. 이들 화합물들은 저자에 의하여 보고된 바 있는 cochlioquinol이라 명명된 화합물의 유도체들로서 지금까지 보고된 바 없는 새로운 물질이며 숙주식물 중의 하나인 이탈리안 라이그라스에 대하여 활성(20~70%)을 나타내는 것으로 보아 병원균의 병징 발현에 관여하는 것으로 보여진다.

• The Plant Pathology Journal
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• 제26권3호
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• pp.231-237
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• 2010

The heat-inactivated (at $121^{\circ}C$ for 20 min) conidial suspension of Bipolaris cactivora (HICS) was evaluated for the control of Bipolaris stem rot of cactus caused by B. cactivora. Severe rot symptoms were developed on the cactus stem discs inoculated with B. cactivora from 5 days after inoculation. However, only small brownish spots developed on the stem discs treated with HICS 2 days prior to the pathogen inoculation. HICS also reduced symptom development on cactus stem discs inoculated with other fungal pathogens such as Alternaria alternata, Colletotrichum gloeosporioides, and Fusarium oxysporum, suggesting its disease-inhibitory efficacy may not be pathogen-specific. HICS significantly reduced severities of the stem rot disease on several cactus species including Hylocereus trigonus, Cereus peruvianus, Chamaecereus silvestrii and Gymnocalycium mianovichii, but not on Cereus tetragonus. Extensive wound periderms were formed in the stem tissues of inoculation and/or wounding sites on C. peruvianus treated with HICS alone or prior to the pathogen inoculation, but not on C. tetragonus, indicating the structural modifications may be related to the mechanism of disease suppression by HICS. HICS also reduced the disease development on the grafted cactus (H. trigonus stock and G. mianovichii scion) with the control efficacy nearly equivalent to the application of a commercial fungicide. All of these results suggest HICS can be used as an environmental-friendly agent for the control of the cactus stem disease.

• The Plant Pathology Journal
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• 제16권6호
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• pp.325-327
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• 2000

A leaf spot of rye (Secale cereale L.) was observed during the summer 1999 in Korea. A fungus associated with the disease was identified as Bipolaris sorokiniana (Sacc.) Shoem., based on the morphological characteristics of conidia and conidiophores. Pathogenicity of the fungus was proven by artificial inoculation on rye plants. This is the first record of leaf spot on rye caused by B. sorokiniana in Korea.

• 한국식물병리학회지
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• 제13권1호
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• pp.18-21
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• 1997

Bipolaris panici-miliacei, Cercospora fusimaculans, Fusarium moniliforme and Rhizoctonia solani were pathogenic fungi detected from 5 seed samples of common millet (Panicum miliaceum). Morphological characters of B. panici-miliacei were as follows. Conidiophores were dark olivaceous brown, simple, cylindrical, geniculate, and septate. Conidia were fusoid, dark olivaceous brown, tapering gradually toward the ends, straight to slightly curved, 3~13 distoseptate, and 29.4~155.4$\times$10~26 ${\mu}{\textrm}{m}$ in size with dark hilum included within the contour of the basal cell. Seed infection with B. panici-miliacei caused seed rotting, coleoptile spot, and seedling blight of common millet plants. According to the inoculation experiments, B. panici-miliacei showed strong virulence on the young seedlings of common millet, but very weak virulence on the young seedlings of rice (Oryza sativa) and foxtail millet (Setaria italica).

• 식물병연구
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• 제7권1호
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• pp.56-59
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• 2001

Stem rot of cacti was found at major cultivating areas including Koyang, Ansung and Eumsung of Korea in 2000. Bipolaris cactivora was consistently isolated from the lesions. The disease occurred on different species of cactus including Cereus peruvianus, C. neopithahaja f. monstruo년, C. tetragonus, Chamaeceresu silestrii, Ch. silvestrii, f. variegata, Gymnocalcium mihanovichii var. friedrichii. G. denudatum var. pentacantha, Hylocereus trigonus and Isolatocereus dumortier. Major symptoms on the cactus species except H. trigohus were almost identical. A rapid rot of the upper portion of the catus stem appeared, and became blackened and somewhat dry. On H. trigonus, the symptom was initially light yellow, water-soaked lesion, turned into light brown and dried to death. According to pathogenicity test, 10 out of 16 cactus species and varieties tested produced identical symptoms as found in the field. However, the fungi did not show pathogenicity to Notocactus scopa, Echinocactus grusonii, Eriocactus leninghausii, Lobivia nealeana, Mammillaria elongata var. intertexta.

• The Plant Pathology Journal
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• 제29권1호
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• pp.42-51
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• 2013

One of the most important limiting factors for the production of the grafted cactus in Korea is the qualitative and quantitative yield loss derived from stem rots especially caused by Bipolaris cactivora. This study is aimed to develop microbial control agents useful for the control of the bipolaris stem rot. Two bacteria (GA1-23 and GA4-4) selected out of 943 microbial isolates because of their strong antibiotic activity against B. cactivora were identified as Bacillus subtilis and B. amyloliquefaciens, respectively, by the cultural characteristics, Biolog program and 16S rRNA sequencing analyses. Both bacterial isolates significantly inhibited the conidial germination and mycelial growth of the pathogen with no significant difference between the two, of which the inhibitory efficacies varied depending on the cultural conditions such as temperature, nutritional compositions and concentrations. Light and electron microscopy of the pathogen treated with the bacterial isolates showed the inhibition of spore germination with initial malformation of germ tubes and later formation of circle-like vesicles with no hyphal growth and hyphal disruption sometimes accompanied by hyphal swellings and shrinkages adjacent to the bacteria, suggesting their antibiotic mode of antagonistic activity. Control efficacy of B. subtilis GA1-23 and B. amyloliquefaciens GA4-4 on the cactus stem rot were not as high as but comparable to that of fungicide difenoconazole when they were treated simultaneously at the time of pathogen inoculation. All of these results suggest the two bacterial isolates have a good potential to be developed as biocontrol agents for the bipolaris stem rot of the grafted cactus.

• 농업과학연구
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• 제29권2호
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• pp.91-97
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• 2002

식물병원균 Bipolaris sorokiniana 배양 추출물로부터 이탈리안 라이그라스 및 논피의 유근신장을 억제하는 활성물질을 분리 정제하여 각종 기기분석을 통하여 화학구조를 결정하였다. 이들 화합물들은 분자식이 $C_8H_8O_3$인 benzenoid 화합물인 3-methoxybenzoic acid와 3-hydroxy benzoic acid methyl ester로 숙주식물의 유근신장을 1000ppm에서 90% 이상 저해하였다. 이들 화합물은 식물체의 잎과 줄기에서 분리되어 항균활성 및 항류마티스 활성이 있음이 보고된바 있으나 B. sorokiniana로부터 분리되어 제초활성에 관하여 보고하기는 본 논문이 처음이다.