• 식물병연구
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• 제13권3호
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• pp.207-210
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• 2007

2007년 5월 전북 전주의 식물원에서 판매중인 아이비에서 줄기 하부가 검게 썩으며 급격히 말라죽는 증상으로부터 병원균을 분리 동정한 결과 Phytophthora cinnamomi로 동정되었다. 병원균의 형태적 특성은 비 돌출형의 탈락성이 없는 계란형, 장타원형 혹은 서양배형의 유주자낭을 형성하였고, 크기는 평균 $33.8{\times}16{\mu}m$였고, 구형의 후막포자를 다량 형성하였으며, 크기는 평균 직경이 $19.7{\mu}m$였다. 유성생식형은 자웅이주로 A1 mating type이 관찰되었고 난포자의 크기는 직경이 $26.2{\mu}m$였다. 균사의 생육적온은 $25{\sim}30^{\circ}C$였다. 이상과 같이 국내 최초의 P. cinnamomi에 의한 아이비줄기썩음병의 발생을 보고하는 바이다.

• 식물병연구
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• 제26권2호
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• pp.109-115
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• 2020

A disease causing leaf blight and vine rot was recognized on kudzu plants (Pueraria lobata) in Korea since 1991. A species of Phytophthora has been repeatedly isolated from the infected leaves. Identification in species level of the Phytophthora sp. remained unsolved. An isolate, KACC 47616 originally collected from Manchon Park in Daegu, has been kept in our laboratory. In 2013, three new isolates, KACC 47617 and KACC 47618 from Yeongyang and KACC 47619 from Gunwi in Gyeongbuk province, were collected and examined to classify up to species level by characterizing morphology, response to temperature and phylogenetic relationship. On the basis of morphological characters such as the nature of hyphal swelling, sporangia and sex organs, absence of chlamydospore production, optimum temperature for mycelial growth, and internal transcribed spacer rDNA and cytochrome oxidase subunit 1 sequence analysis of the pathogen, the causal fungus of kudzu plant was identified as Phytophthora asiatica.

• 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.

• The Plant Pathology Journal
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• 제15권4호
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• pp.228-235
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• 1999

Genetic diversity of ninety-five Korean isolates of Phytophthora was investigated on the basis of PCR-RFLP of ribosomal DNA. The isolates were previously identified as following fifteen species by mycological and cultural characteristics; P. boehmeriae, P. cactorum, P. cambivora, P. capsici, P. cinnamoni, P. citricola, P. citrophthora, P. cryptogea, P. drechsleri, P. erythroseptica, P. infestans, P. megasperma, P. nicotianae, P. palmivora and P. sojae. The regions of small subunit (SSU) and internal transcribed spacer (ITS) of rDNA were amplified with primer pair, NS1 and ITS4, by polymerase chain reaction (PCR) and digested with nine restriction enzymes. P. boehmeriae, P. cactorum, P. cambivora, P. capsici, P. cinnamomi, P. citricola, P. citrphthora, P. infestans, P. nicotianae and P. palmivora showed specific band patterns for each species. However, P. sojae and P. erythroseptica presented identical band patterns and P. cryptogea, P. drechsleri and P. megasperma were divided into six groups, which were not compatible with delineation of the species. A group originated from cucurbits showed distinct band patterns from other groups, but the other five groups were closely related within 96.0% similarity, forming one complex group. Consequently, Korean isolates of Phytophthora were divided into thirteen genetic groups and each group was readily differentiated by comparing digestion patterns of AvaII, HaeIII, MboI, HhaI and MspI. Therefore, PCR-RFLP of rDNA using the five enzymes can be used to differentiate or identify the Phytophthora species reported in Korea so far.

• The Plant Pathology Journal
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• 제16권1호
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• pp.29-35
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• 2000

The internal transcribed spacer regions (ITS I, 5.8S and ITS II) of the ribosomal DNAs were amplified from Korean isolates of Phytophthora spp. and sequenced to characterize them. Sequences from 33 isolates previously identified as P. boehmeriae, P. cactprum, P. cambivora, P. capsici, P. cinnamomi, P. erythroseptica, P. infestans, P. megasperma, P. melonis, P. nicotianae, P. palmivora and P. sojae were compared with published sequences, and a phylogenetic tree was produced. All isolates belonging to 10 species, P. cactorum, P. cambivora, P. capsici, P. cinnamomi P. citricola, P. infestans, P. nicotianae, P. palmivora and P. sojae were clearly clustered into published isolates of each species above 97% bootstrap value. Cucurbits isolates of Phytophthora previously identified as either P. melonis or P. drechsleri showed distinct evolutionary lineages from the P. megasperma was closely related to isolates of P. cryptogea-P. drechsleri showed distinct evolutionary lineages from the P. cryptogea-P. drechsleri complex group, indicating that P. melonis is a valid species. A Korean isolate of P. megasperma was closely related to isolates of P. erythroseptica showed distant genetic relationship with published isolates of P. erythroseptica (CBS 956.87). It is probable that the two Korean isolates could be genetically different from foreign isolates or misidentified. A grouping of species according to ITS sequence divergence matched, to some degree, the broad classification based on type of papilla. However, a separation of semi-papillate species and papillate species was not wvident in this study.

• 한국균학회지
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• 제27권6호
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• pp.394-398
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• 1999

형태학적특징으로 분류된 6개의 그룹(GI, GII, GIII, GIV, GV, GVI)에 속하는 수종의 Phytophthora species 간의 RAPD fingerprinting 양상을 살펴보았다. Phytophthora의 일부 균주는 배양시 균사생장 형태가 매우 유사하며, 분리를 위한 여러 가지 특징이 중첩되기 때문에 정확한 동정이 난해하다. 본 실험결과 감자에서 분리한 균주 뿐만 아니라 토마토에서 분리한 P. infestans에서 RAED 분석을 통해서 동정이 가능함을 알 수 있었다. 증폭된 절편들은 $0.3{\sim}3.2\;kb$의 범위에 속했다. 전체 145개 밴드 중에서 109개의 polymorphic band를 얻었다. 7개의 P. infestans 간에는 최저 0.92에서 최고 0.99의 높은 유사성을 보였으며 감자를 기주로한 isolate 3 과는 $0.93{\sim}0.95$를 보였고, P. capsici 간에는 $0.77{\sim}0.86$의 유연성을 보였으며 약 80%의 수준에서 효과적으로 grouping 되었다. 특히 OPA-20를 사용하여 genus Phytophthora 내에 공통으로 존재하는 600 bp의 common band와 P. infestans에만 형성되는 680 bp의 specific band를 얻어 marker로서의 활용이 가능함을 알 수 있었다. 형태학적으로는 GVI 속하는 P. cinnamomi와 P. cryptogea간의 RAPD fingerprinting pattern에서 상이한 band 패턴을 나타냈다. 특히 OPA-04, OPA-17, OPA-18, OPA-19, OPB-12에서는 major band의 molecular weight와 생성밴드의 수에서 뚜렷한 차이를 보였다. 그리고 두 균주간의 유사성은 0.67로 나타났다. GV에 속하는 P. megasperma와 P. sojae의 경우, 유사성 정도가 0.65으로 나타났으며 이는 다른 균주와의 유사정도 보다 가장 높은 수준을 보였다. 또한 이들 균주는 OPA-08, OPA-17, OPA-19를 사용했을 때 단일 major band에서 큰 차이를 보였다.

• Journal of Microbiology and Biotechnology
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• 제23권1호
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• pp.29-35
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• 2013

A Nodulisporium sp. (Hypoxylon sp.) has been isolated as an endophyte of Thelypteris angustifolia (Broadleaf Leaf Maiden Fern) in a rainforest region of Central America. It has been identified both on the basis of its morphological characteristics and by scanning electron microscopy as well as ITS sequence analysis. The endophyte produces volatile organic compounds (VOCs) that have both fuel (mycodiesel) and use for biological control of plant disease. When grown on potato dextrose agar, the organism uniquely produces a series of ketones, including acetone; 2-pentanone; 3-hexanone, 4-methyl; 3-hexanone, 2,4-dimethyl; 2-hexanone, 4-methyl, and 5-hepten, 2-one and these account for about 25% of the total VOCs. The most abundant identified VOC was 1,8 cineole, which is commonly detected in this group of organisms. Other prominent VOCs produced by this endophyte include 1-butanol, 2-methyl, and phenylethanol alcohol. Moreover, of interest was the presence of cyclohexane, propyl, which is a common ingredient of diesel fuel. Furthermore, the VOCs of this isolate of Nodulisporium sp. were selectively active against a number of plant pathogens, and upon a 24 h exposure caused death to Phytophthora palmivora, Rhizoctonia solani, and Sclerotinia sclerotiorum and 100% inhibition to Phytophthora cinnamomi with only slight to no inhibition of the other pathogens that were tested. From this work, it is becoming increasingly apparent that each isolate of this endophytic Nodulisporium spp., including the Daldina sp. and Hypoxylon spp. teleomorphs, seems to produce its own unique set of VOCs.