• The Plant Pathology Journal
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• 제24권2호
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• pp.125-130
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• 2008

Various kinds of leaf spots and blights were found in kiwifruit (Actinidia deliciosa) orchards on 2006 in Korea. Disease incidences were quite variable between open-field and rain-proof shelter. Rate of diseased leaves was recorded as about 70% at open-field orchards in late season but use of rain-proof vinyl shelters alleviated the disease incidences by 20%. Angular leaf spots appeared at early infection stage on June and several other symptoms were also recognized as the disease developed afterward. On September, brown leaf blights were the most frequent, followed by grayish brown ring spots, silvering gray leaf blights, zonate leaf blights, dark brown ring spots and angular leaf spots at open-field orchards. Four fungal species were frequently isolated from the disease symptoms. Phomopsis sp. was the most predominant fungus associated with the leaf spot and blight symptoms on kiwifruit, followed by Glomerella cingulata, Alternaria alternata and Pestalo-tiopsis sp. Phomopsis sp. was commonly isolated from angular leaf spots, silvering gray leaf blights, and zonate brown leaf blights. G. cingulata, A. alternata and Pestalotiopsis sp. were isolated from grayish brown ring spots (anthracnose), brown ring spots and zonate dark brown leaf blights. Typical symptoms appeared on the wounded and unwounded leaves, which were inoculated by each of Phomopsis sp., G. cingulata, and Pestalotiopsis sp., but A. alternata caused symptoms only on the wounded leaves.

• 한국식물병리학회지
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• 제13권4호
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• pp.195-199
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• 1997

1995년 12월 전라북도 지역 내에 유통되고 있는 시클라멘의 꽃잎 중앙부에 진회색~흑색 원형 반점을 형성하거나, 꽃잎 주변에 흑색 수침상을 나타내는 탄저병의 발생이 관찰되었다. 병반으로 붜 분리된 균은 PDA 배지상에서 회백색을 띄었으며, 8.3~15.0${\times}$2.5~6.3 ${\mu}m$ 크기의 양끝이 둥근 무색 단포의 원통형~타원형의 분새오자를 형성하였고, 갈색 곤봉형의 부착기와 이병조직에서 갈색 둥근형의 분생자층을 형성하였다. 이에 따라 시클라멘 탄저병징에서 분리한 병원균은 국내에서 미보고된 Colletotrichum gloeosporioides로 동정되었으며, 균사생장 및 분생포자 형성을 위한 배양적정 온도는 25~30$^{\circ}C$였다.

• Applied Biological Chemistry
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• 제44권3호
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• pp.191-196
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• 2001

새로운 살균제 농약 개발을 목적으로 삼불화메틸기 디히드로-1,4-옥사티인기가 포함된 ${\alpha},{\beta}$-불포화 카르복스아미드 유도체 5를 합성하였다. 삼불화 ${\beta}$케토에스테르 유도체 6을 염화한 다음 1,2-메르캡토에탄을과 반응시켜 중간체 1,4-옥사티안 유도체 11을 얻었다. 중간체 11의 정제없이 히드록시기를 염소로 치환한 다음 중간체 10을거쳐 트리에틸 존재하에서 탈염화하여 삼불화메틸기가 포함된 디히드로-1,4-옥사티인 에틸에스테르 9를 합성하였다. 에스테르 9를 가수분해하여 생성된 카르복실산 12의 히드록시기를 염소로 치환하여 활성화한 다음 여러 가지 아민 유도체와 반응시켜 삼불화메틸기가 포함된 디히드로-1,4-옥사티인 카르복스아미드 유도체 5를 합성하였다. 합성된 화합물을 대표적인 6종의 식물병원균, 벼 도열병, 벼 잎집무의마름병, 오이 잿빛곰팡이병, 토마토 역병, 밀 붉은 녹병, 그리고 보리 흰가루병 등에 대한 in vivo 항균력을 시험하였다. 그 결과, 페닐기의 meta 위치에 이소프로폭시기 또는 이소프로필기가 치환된 화합물이 벼 잎집무의마름병과 밀 붉은녹병에 대한 강한 항균력을 나타냈다.

• 아시안잔디학회지
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• 제14권1호
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• pp.241-250
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• 2000

In 1997, a new disease on creeping bentgrass and Kentucky bluegrass occurred in the green and fairway of a few golf courses in Korea. The disease spread gradually throughout the country and became a threat to turfgrass management. Symptoms of the disease consisted of small, circular, and sunken patches sized 3~5cm in diameter. The disease named as a dollar spot following its characteristic symptoms of circular blight and bleach on the green. The disease peaked two times in a year from April to June and from late August to October and white cottony mycelia of the causal fungus developed on diseased turfs in the early morning when the conditions were favored. A causal fungus was consistently isolated from the infected tufgrass and seven isolates originated from seven golf courses located in six provinces were selected for further study. The fungus produced abundant white aerial mycelia on PDA and turned to dark gray or light brown as it aged. Width of the mycelium was ca. $5~8\mu\textrm{m}$. While sclerotia were not readily formed on the medium, scattered small and dark colored stromata were developed on the surface. The fungus grew well on PDA between 5 to $30^{\circ}C$ and maximally around $25^{\circ}C$. Based on investigated mycological and cultural characteristics, the causal agent of dollar spot was identified as Sclerotinia homoeocarpa. The fungus showed strong pathogenicity to several turfs as creeping bentgrass, Kentucky bluegrass, perennial ryegrass, tall fescues, and zoysiagrass.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.25-27
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• 2003

Since 1993, a total of 50 problematic plant diseases unrecorded in Korea were surveyed in Gyeongnam province. Totally 34 new host plants to corresponding pathogens investigated in this study were 5 fruit trees, 9 vegetables, 12 ornamental plants, 3 industrial crops, and 5 medicinal plants. Among the newly recorded fruit tree diseases, fruit rot of pomegranate caused by Coniella granati and Rhizopus soft rot of peach caused by Rhizopus nigricans damaged severely showing 65.5% and 82.4% infection rate. Among the vegetable diseases, corynespora leaf spot of pepper caused by Corynespora cassiicola and the crown gall of pepper caused by Agrobacterium tumefaciens, powdery mildew of tomato caused by Oidiopsis taurica were the most severe revealing 47.6%, 84.7%, and 54.5% infection rate in heavily infected fields, respectively. In ornamental plants, collar rot of lily caused by Sclerotium rolfsii, gray mold of primula caused by Botrytis cinerea, soot leaf blight of dendrobium caused by Pseudocercospora dendrobium, sclerotinia rot of obedient plant caused by Sclerotinia sclerotiorum showed 32.7 to 64.8% disease incidence. On three industrial plants such as sword bean, broad bean, and cowpea, eight diseases were firstly found in this study. Among the diseases occurring on broad bean, rust caused by Uromyces viciae-fabae and red spot caused by Botrytis fabae were the major limiting factor for the cultivation of the plant showing over 64% infection rate in fields. In medicinal plants, anthracnose of safflower caused by Collectotrichum acutatum was considered the most severe disease on the plant and followed by collar rot caused by Sclerotium rolfsii.(중략)

• The Plant Pathology Journal
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• 제34권3호
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• pp.241-249
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• 2018

Commercial biocontrol of microbial plant diseases and plant pests, such as nematodes, requires field-effective formulations. The isolate Pseudomonas chlororaphis O6 is a Gram-negative bacterium that controls microbial plant pathogens both directly and indirectly. This bacterium also has nematocidal activity. In this study, we report on the efficacy of a wettable powder-type formulation of P. chlororaphis O6. Culturable bacteria in the formulated product were retained at above $1{\times}10^8$ colony forming units/g after storage of the powder at $25^{\circ}C$ for six months. Foliar application of the diluted formulated product controlled leaf blight and gray mold in tomato. The product also displayed preventative and curative controls for root-knot nematode (Meloidogyne spp.) in tomato. Under laboratory conditions and for commercially grown melon, the control was at levels comparable to that of a standard commercial chemical nematicide. The results indicated that the wettable powder formulation product of P. chlororaphis O6 can be used for control of plant microbial pathogens and root-knot nematodes.

• The Plant Pathology Journal
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• 제21권3호
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• pp.297-300
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• 2005

Racodium therryanum from Korea is described here for the first time. This fungus is characterized by that it is isolated from conifer seeds and seedlings, including Abies, colonies are dark green to dark gray and intricate, and it forms chlamydospores in cultures. This pathogenic fungus was isolated from seeds of Abies koreana growing on Mt. Halla, Jeju island. The fungus stopped growth more than at $30^{\circ}C$ but grew even at $O^{\circ}C$. This fungus infected seeds of A. koreana under the snow during winter season. There is a high probability that this fungus affects the natural regeneration of A. koreana on Mt. Halla.

• 식물병연구
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• 제10권1호
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• pp.1-7
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• 2004

2003년은 냉해의 해였다. 3월부터 7월까지 저온이 지속되었고 생육기 내내 비가 자주 내려 강수량은 평년의 1.6배 일조시간은 평년의 68％ 수준이었다. 이 때문에 벼도 열병, 흰잎마름병이 심하게 발생하였고 강우에 의해 전반되는 역병이 대발생하여 고추의 경우 전국 재배면적의 55％가 피해를 입었다. 이외에 저온다습 조건에서 발생이 많은 잿빛곰팡이병 균핵병, 노균병이 전년에 비해 크게 증가하였고 과수의 경우 사과갈색무늬병, 배검은별무늬병이 대발생하여 큰 피해를 가져왔다.

• 농약과학회지
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• 제5권3호
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• pp.18-25
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• 2001

46종 식물의 에탄올 추출물을 대상으로 기주식물상의 주요 식물병 6종에 대하여 방제효과를 온실실험으로 조사하였다. 46종의 시험식물 추출물을 pot당 5, 10 mg씩 처리하였을 때 해바라기꽃과 옥수수잎 추출물이 벼도열병에 80% 이상의 방제효과를 나타내었다. 5 mg의 농도에서 해바라기 잎과 꽃, 쑥갓 호박씨, 토마토 옥수수와 옥수수익의 추출물이 잿빛곰팡이병에 80% 이상의 방제효과를 나타내었고, 밀녹병에 대해서는 피망, 호박씨, 해바라기씨, 토마토 및 아욱의 추출물이 80% 이상의 방제효과를 나타내었다. 보리흰가루병에 대해서는 오이, 해바라기씨, 감자 및 옥수수와 잎의 추출물이 10 mg의 농도에서 80% 이상의 방제효과를 나타내었다. 그러나 토마토역병과 벼잎집무늬마름병에 대해서는 모든 시료가 활성을 나타내지 않았다. 살균치 carbendazim, diethofencarb, procymidone 저항성 균주에 대해서는 해바라기잎과 꽃의 추출물이 모든 균주에 높은 방제효과를 나타내었고, 쑥갓과 해바라기씨의 추출물은 SSR(carbendazim 감수성, diethofencarb 감수성, procymidone 저항성 균주) 및 RSR(carbendazim 저항성, diethofencarb 감수성, procymidone 저항성 균주)에 90% 이상의 방제효과를, 옥수수와 잎은 SSR(carbendazim 감수성, diethofencarb 감수성, procymidone 저항성 균주)에 강한 방제효과를 보였다. 그러나 RROS(carbendazim 저항성, diethofencarb 저항성, procymidone 감수성 균주)에 대해서는 사용된 시료 중 토마토 추출물만이 방제효과를 보였다.

• The Plant Pathology Journal
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• 제33권5호
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• pp.488-498
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• 2017

The aim of this study was to identify volatile and agardiffusible antifungal metabolites produced by Bacillus sp. G341 with strong antifungal activity against various phytopathogenic fungi. Strain G341 isolated from four-year-old roots of Korean ginseng with rot symptoms was identified as Bacillus velezensis based on 16S rDNA and gyrA sequences. Strain G341 inhibited mycelial growth of all phytopathogenic fungi tested. In vivo experiment results revealed that n-butanol extract of fermentation broth effectively controlled the development of rice sheath blight, tomato gray mold, tomato late blight, wheat leaf rust, barley powdery mildew, and red pepper anthracnose. Two antifungal compounds were isolated from strain G341 and identified as bacillomycin L and fengycin A by MS/MS analysis. Moreover, volatile compounds emitted from strain G341 were found to be able to inhibit mycelial growth of various phytopathogenic fungi. Based on volatile compound profiles of strain G341 obtained through headspace collection and analysis on GC-MS, dimethylsulfoxide, 1-butanol, and 3-hydroxy-2-butanone (acetoin) were identified. Taken together, these results suggest that B. valezensis G341 can be used as a biocontrol agent for various plant diseases caused by phytopathogenic fungi.