• 한국식물병리학회지
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• 제14권5호
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• pp.519-525
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• 1998

Intraspecific genetic diversity of Korean isolates of Phytophthora drechsleri was investigated based on PCR-RFLP of rDNA along with closely related species in the genus; P. cryptogea, P. melonis, P. erythroseptica, P. cinnamomi, P. cambivora and P. cactorum. Gene regions of nuclear small subunit and internal transcribed spacer (ITS) in rDNA were amplified with polymerase chain reaction and digested with 9 restriction enzymes. Phytophthora species was readily differentiated from each other based on the digestion patterns, however, P. cryptogea was not separable from some isolates of P. drechsleri. Twenty one isolates of P. drechsleri originated from 15 host plants were divided into three distinct groups designated as PdG1, PdG2 and PdG3, respectively. Four isolates in PdG1 were originated from green vegetables and tomato and nine isolates in PdG2 were mainly isolated from medicinal plants. The two groups showed 95.3% homology and four isolates of P. cyptogea came under the groups. However, Eight isolates in PdG3 collected from cucurbits were clearly differentiated from those of PdG1 and PdG2 by 66.5% homology, but completely matched with a Taiwan isolate of P. melonis. Results indicated that three distinct groups exist in Korean isolates of P. drechleri and each group has host preference. In addition, reclassification of the cucurbits isolates are reserved because of their distinct genetic characters from other intraspecific groups in P. drechsleri.

• 한국식물병리학회지
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• 제14권5호
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• pp.445-451
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• 1998

A severe Phytophthora rot of strawberry caused by a species of Phytophthora has been widely occurred at major cultivation areas of Kimhae on August in 1997. Incidence of the disease was obtained in the range of 69.2~83.6% in surveyed 4 fields and showed an average of 75.2%. A species of Phytophthora was mostly isolated from the crown of infected strawberry plants and all the isolates were identified as P. nicotianae var. nicotianae (=P. parasitica). The fungus showed strong pathogenicity on strawberry by inoculation test. As a result of the leaf inoculation using mycelial disks of the fungus, both leaves and petioles were darkly browned, and were finally blighted. As a result of the root inoculation of zoospore suspension, both roots and crowns were rotten with dark brown. Although the fungus produced sporangia either on V-8 juice agar medium or liquid medium, the sporangia observed on the liquid medium appeared to be broadly turbinate and noncaducous. Moreover the fungus cultured on the liquid medium often produced sporangia having two papilla. The number of zoospores in sporangia was found to be ranged from 3 or 4 to as many as 20 or 25. In addition, the released zoospore from the sporangium became the cystospore during the prolonged culture of the fungus. The sporangia were measured as av. 49$\times$35 ${\mu}{\textrm}{m}$ with l/b ratio of 1.43. All isolates from crowns were heterothallic and A1 mating type since oospores were abundantly formed on clarified V-8 juice agar by dual culture with P. capsici A2 mating type. Aplerotic oospores were sized 24-26 ${\mu}{\textrm}{m}$. Antheridia were always amphigynous and recoreded an average of 12$\times$10 ${\mu}{\textrm}{m}$. Hyphal swlling were easily observed, and terminal or intercalary chlamydospores were abundantly formed on V-8 juice agar as well as in C/Z solution and sized av. 28.2 ${\mu}{\textrm}{m}$. This is the first report of Phytophthora rot of strawberry in Korea.

• 한국균학회지
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• 제22권4호
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• pp.281-285
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• 1994

Phytophthora cactorum으로부터 분리된 유주자(遊走子)는 균사 생장이 상대적으로 균일하고 균사 생장분포가 모체(母體) 균주(菌株)와 유사하였으나, 분리된 난포자(卵胞子)는 균사생장분포가 매우 다양하였다. 또한, 균총의 특징은 난포자에서 크게 다양한 반면, 유주자에서는 균일하였다. 이 결과는 P. cactorum의 균사생장과 균총의 모양을 결정하는데 있어 다양한 유전자가 관여하고 있으며, 몇몇 역병균이 생장하는 동안에 이배체성 생식을 나타낼 수 있다는 점을 시사한다.

• 한국균학회지
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• 제30권1호
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• pp.66-72
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• 2002

Phytophthora capsici 집단의 유전적 특성 분석용 DNA marker를 선발하고자 HindIII로 처리된 P. capsici 95CY3119 균주의 genomic DNA library를 임의로 cloning 시킨 후 southern blot 분석을 실시하여 선발된 clone들의 특성을 조사하였다. Probe로 사용하기 위해 선발된 clone 내에 삽입된 DNA 단편들은 HindIII로 처리된 P. capsici 95CY3119의 genomic DNA와 특이적으로 강하게 반응했다. 조사된 probe 중 PC9은 HindIII로 처리된 국내 P. capsici 균주들의 genomic DNA와 Southern 분석시 많은 밴드를 형성하였으며, 분리포장 단위별 균주들 간에는 물론 동일 포장 분리균주들 간에도 그 차이를 나타냈다. 그 밴드 양상을 기초로 집괴분석을 실시한 결과, 각 균주의 유전적 다양성이 잘 나타났다. Prove PC22는 다른 Phytophthora속과 Pythium속 균주들의 genomic DNA들과의 Southern hybridization에서는 반응을 나타내지 않았지만 특이적으로 P. capsici 균주들과는 다수의 밴드를 형성하였다. 이들 P. capsici 종특이적 DNA probe들은 추후 국내 및 전세계에 분포하는 P. capsici 집단의 유전적 다양성 분석 및 종동정에 유용한 marker로서 활용될 수 있을 것이다.

• Journal of Forest and Environmental Science
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• 제23권1호
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• pp.65-71
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• 2007

2000년대에 이르러 새로운 역병균들이 발생되어 산림에 피해를 주고 있는 가운데 최근 산림에 식재되어 있는 밤나무에서도 역병균에 의해 잉크병이 큰 문제가 되고 있다. 우리나라에서도 2005년 경상남도와 전라남도 일부지역에서 잉크병과 비슷한 증상이 나타나 2006년 11월 역병균 선택배지를 이용하여 분리하여 형태학적 분자생물학적 비교분석하였으며, 코흐의 법칙을 완성하기 위해 병원성 실내 외 검정을 실시하였다. 또한 P. katsurae와 계통분류학상 매우 비슷한 P. hevae와 유전적 관계를 살펴보기 위해 다른 나라에 분리된 균주들과 비교분석을 실시하였다. 그 결과, 한국에서는 아직까지 보고되어 있지 않은 Phytophthora katsurae로 동정되었으며 병원성 검정실험을 통해 코흐의 법칙을 만족시켰다. 밤나무 품종별 민감도에 약간의 차이를 확인하였으며 일본균주와 뉴질랜드균주와 유전자 염기서열상 100% 일치하는 것으로 나타났다.

• 한국식물병리학회지
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• 제14권4호
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• pp.299-302
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• 1998

V8 juice agar (V8A) has been the most popular and commonly used medium for growth and reproduction of Phytophthora. However, frequently V8 vegetable juice is not available or difficult to obtain in Korea. We therefore developed widely accessible medium to substitute for V8A using domestically available five juices; two carrot (KCJA), two tomato (KTJA) and a vegetable-mix (KVMA). To prepare 10% juice medium, each vegetable juice 100 ml, DW 900 ml, agar 17 g and Ca CO3 0.5∼1.0g were supplemented to adjust pH ca. 6.0 Mycelial growth of P. cactorum and P. capsici on KTJA and KVMA was equally effective as V8A for the growth of P. cactorum, P. capsici, P. drechsleri and P. nicotianae under light. Sporangial production of P cactorum, P. capsici and P. nicotianae on KTJA and KVMA was as good as V8A and slightly better than CKJA, but the difference was insignificant by P. cactorum and P. nicotianae. The four fungi successfully formed oospores on all the media although the numbers were varied among species and media. While KTJA was the best for P. cactorum and P. capsici, V8A was the best for P. capsici and P. drechsleri. However, KCJA stimulated highest number of oopspores of P. nicotianae. Overall results showed that domestically available vegetable juices were highly effective on growth and reproduction of Phytophthora and comparable to V8 juice. Therefore, the domestic juice medium can be successfully replaced V8A in Phytophthora study.

• 식물병연구
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• 제8권1호
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• pp.41-44
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• 2002

＇97∼＇98년에 경북지역의 대구와 경산, 군위, 영천, 청도등 대추과원에서 과실에 역병이 발생되었다. 병징은 과실이 적갈색의 반점이 생기며 심하면 미이라가 되고, 말라서 조기낙과되며 엽병과 신초에도 마름증상을 나타내기도 했다. 이병과에서 2종의 역병균이 검출되었는데 총 18개 역병균중 6균주는 P. nicotiamae로 동정되었고, 나머지 12균주는 P. palmivora로 동정되었다. P. nicotianae는 유두돌기가 뚜렷하고 비탈락성인 구형 혹은 난형의 유주자낭과 다량의 후막포자를 형성하였으며 유성생식형은 자웅이주로 A1 mating type이 조사되었다. P. palmivora는 유주자낭이 유두돌기가 뚜렷하고 탈락성이며 장타원형 혹은 난형, 구형 등이었고, 다량의 후막포자를 형성하였으며 유성생식형은 자웅이주로 A1 mating type이 조사되었다. 2종의 역병균 모두 대추와 배에 강한 병원성을 나타내었으나. 사과에는 병원성이 없었다. P. nicotiamae 와 P. palmivora에 의한 대추 역병은 국내에서 최초로 보고되는 것이다.

• The Plant Pathology Journal
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• 제15권5호
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• pp.287-294
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• 1999

A technique based on the polymerase chain reaction (PCR) for the specific detection of genus Phytophthora and Phytophthora cryptogea-P. drechsleri complex group was developed using nucleotide sequence information of ribosomal DNA (rDNA) regions. The internal transcribed spacers (ITS) including 5.8S were sequenced for P. cryptogea-P. drechsleri complex group and its related species. Two pairs of oligonucleotide primers were designed. Primer pair ITS1/Phy amplified ca. 240 bp fragment in 12 out of 13 specie of Phytophthora, but not in Pythium spp., Fusarium spp.and Rhizoctonia solani. Primer pair rPhy/Pcd amplified 549 bp fragment only in P. cryptogea-P. drechsleri complex group, but not in other Phytophthora spp.and other genera. Specific PCR amplification using the primers was successful in detecting Phytophthora and P. cryptogea-P. drechsleri complex group in diseased plants.

• 한국식물병리학회지
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• 제14권4호
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• pp.294-298
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• 1998

Since 1995, boxthorn bight caused by Phytophthora spp. has occurred at Chongyang areas in Chungnam province. Infected plants showed yellows and wilt at early stage, but the symptom rapidly progressed into blight due to the decay of roots and basal stem tissues. The disease was relatively severe in poorly drained lowlands and incidence reached ca. 20% in some fields. Two species of Phytophthora were constantly isolated from freshly infected roots and asal stems. Among 39 isolates collected, 26 were identified as P. nicotianae and 13 as P. drechsleri based on their mycological characteristics. Both fungi showed strong pathogenicity to boxthorn cv. Chongyang No. 1. However, the former expressed stronger pathogenicity than the latter. Phytophthora blight of boxthorn caused by the fungi has not been reported n Korea previously.

• 한국토양비료학회지
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• 제33권2호
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• pp.121-126
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• 2000

불건전 토양과 건전 토양의 환경을 이해하기 위해 자연적으로 역병에 감염되거나 감염되지 않은 고추와 토마토 시설재배지의 비근권토양, 근권토양, 근면을 채취하고 연구하였다. 시료는 경상남도의 시설재배지에서 1999년 4월에 채집되었으며, 진균의 분리는 희석평판법을 이용하였다. 각 작물 별 재배지에서 25 종의 진균이 분리되었으며 건전 시료보다는 감염 시료에서, 근권이나 근면토양보다 비근권토양에서 더 많은 수의 종이 분리되었다. 역병이 감염되지 않은 시료에서만 Trichoderma sp.가 분리되었으며 각 작물의 서식지별로 분리된 진균의 수는 다양하였다.