• 한국식품과학회지
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• 제35권6호
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• pp.1188-1192
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• 2003

새우나 게 껍질로부터 chitin을 유일한 탄소원으로 하는 집적배양에 의하여 chitinase 활성이 우수한 균주를 2종 분리하였다. 분리균주는 형태학적, 그람염색, 16s rDNA 서열분석을 통하여 Arthrobacter nicotianae로 동정되어, 각각 Arthrobacter nicotianae CH4와 Arthrobacter nicotianae CH13으로 명명하였다. 두 종의 분리균주로부터의 chitinase는 모두 pH $3.0{\sim}9.0$에서 90% 이상의 효소활성을 유지하여 높은 pH안정성을 나타내었다. 온도의 영향은 $20{\sim}60^{\circ}C$ 구간에서 최적 효소 활성의 $70{\sim}90%$를 유지하여 열안정성도 뛰어났다. A. nicotianae CH4와 A. nicotianae CH13이 분비하는 chitinase 조효소를 0.1% colloidal chitin 기질에 반응시켜서 반응산물로 생산되는 chitin 올리고당을 HPLC를 사용하여 분석하였다. A. nicotianae CH4 조효소에 의한 효소반응산물로는 올리고머인 $(GlcNAc)_4$이, A. nicotianae CH13는 단량체인 $(GlcNAc)_1$이 전체 반응산물의 각각 98% 이상 생성되었다.

• 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.

• 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.

• Mycobiology
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• 제43권3호
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• pp.288-296
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• 2015

Thailand is one of the largest citrus producers in Southeast Asia. Pathogenic infection by Phytophthora, however, has become one of major impediments to production. This study identified a pathogenic oomycete isolated from rotted roots of pomelo (Citrus maxima) in Thailand as Phytophthora nicotianae by the internal transcribed spacer ribosomal DNA sequence analysis. Then, we examined the in vitro and in vivo effects of Chaetomium globosum, Chaetomium lucknowense, Chaetomium cupreum and their crude extracts as biological control agents in controlling this P. nicotianae strain. Represent as antagonists in biculture test, the tested Chaetomium species inhibited mycelial growth by 50~56% and parasitized the hyphae, resulting in degradation of P. nicotianae mycelia after 30 days. The crude extracts of these Chaetomium species exhibited antifungal activities against mycelial growth of P. nicotianae, with effective doses of $2.6{\sim}101.4{\mu}g/mL$. Under greenhouse conditions, application of spores and methanol extracts of these Chaetomium species to pomelo seedlings inoculated with P. nicotianae reduced root rot by 66~71% and increased plant weight by 72~85% compared to that in the control. The method of application of antagonistic spores to control the disease was simple and economical, and it may thus be applicable for large-scale, highly effective biological control of this pathogen.

• 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.

• 식물병연구
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• 제14권2호
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• pp.122-126
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• 2008

2007년 7월 전북 전주의 식물원에서 판매중인 아이비에서 줄기와 잎이 갈색으로 썩으며 급격히 말라죽는 증상으로부터 병원균을 분리 동정한 결과 Phytophthora nicotianae로 동정되었다. 병원균의 형태적 특성은 유두돌기가 있고 탈락성이 없는 난형의 유주자낭을 형성하였고, 크기는 평균 $35.4{\times}25.2{\mu}m$었고, 구형의 후막포자를 다량 형성하였으며, 크기는 평균 직경이 28.5 ${\mu}m$였다. 유성생식형은 자웅이주로 A1 mating type이 관찰되었고 난포자의 크기는 평균 직경이 23.3 ${\mu}m$였다. 균사의 생육적온은 $25{\sim}30^{\circ}C$였다. P. nicotianae에 의한 아이비줄기썩음병의 발생은 국내에서는 처음이다.

• 한국응용곤충학회지
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• 제7권
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• pp.57-59
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• 1969

4종의 탄저병균, Colletrichum panacicola, C. gloeosporides, C. truncatum 및 C. nicotianae의 분생포자형성에 미치는 광선의 영향을 감자과당한천배지에서 각 분생포자현탁액을 Petri접시 전면에 접종하여 시험하였다. C. nicotianae를 제외한 세 탄저병균은 지속광선구에서 다른 두구보다 분생포자형성이 증가되었는데 그 두 구간에는 현저한 차이가 없었다. 공시 탄저병균 별로 보면 C. panacicola의 분생포자량이 가장 적었고 C. gloeosporioides는 중간, C. truncatum은 가장 많았다. 분생포자형성량의 차이는 공시 탄저병균(P=0.99), 광선처리 (P=0.95) 및 그 상호작용(P=0,99)에 따라 통계학적으로 유의성이 있었다.

• 한국식물병리학회지
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• 제14권5호
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• pp.452-457
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• 1998

Thirty-eight isolates of Phytophthora sp. caused rots on roots and basal stems were collected from five flowering plants from 1992 to 1997 at eight cultivation areas in Korea. All the isolates were identified as P. nicotianae based on following characteristics. The fungus produced markedly papillate, not caducous and ovoid to spherical sporangia, abundant chlamydospores, and small oospores with amphigynous antheridia only when paired with either A1 or A2 mating type. All isolates grew well at 35$^{\circ}C$ and showed distinct arachnoid colony patterns on CMA and PDA. Sizes of sporangia and chlamydospores of five representative isolates from each plant averaged 43-52$\times$30-38 ${\mu}{\textrm}{m}$ and 28 ~34 ${\mu}{\textrm}{m}$. Mating type of the isolates was either A1 or A2, and oogonia and oospores were measured as 28~31 ${\mu}{\textrm}{m}$ and 21~25 ${\mu}{\textrm}{m}$. PCR-RFLP analysis of rDNA of the five isolates resulted that restriction band patterns of the small subunit and ITS regions were identical to a perilla isolate of P. nicotianae, but distinct from P. cactorum and P. capsici. Cross inoculation tests showed that the five isolates had pathogenicity to lily, christmas cactus, anthurium, baby's breath and carnation with different degrees. However, each isolate showed stronger pathogenicity to its corresponding original host than others. Among five lily cultivars Georgia and Quririna were more susceptible than Napoli and others. This is first report of Phytophthora root and stem rot of lily, Christmas cactus, anthurium, baby's breath and monochoria in Korea.

• 한국식물병리학회지
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• 제14권6호
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• pp.646-650
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• 1998

Mycological characteristics of Phytophthora nicotianae var. nicotianae SPC10 (A1 type) causing Phytophthora rot of strawberry and the resistances of 11 strawberry cultivars against the pathogen were examined. Optimum temperature for the mycelial growth of the pathogen was obtained in the range of 30~35$^{\circ}C$, and the growth was completely stopped under 13$^{\circ}C$ or over 42$^{\circ}C$. Aerial mycelia were abundant on oatmeal agar (OMA), V-8 juice agar (V8A) and lima bean agar (LBA) medium, although there were slight differences, however, on cornmeal agar (CMA) medium, it was a shape of stellate without aerial mycelia. The colony shape on potato dextrose agar (PDA) medium was rough and irregular whereas the mycelial growth was slow, and some aerial mycelia were only produced in the middle of PDA medium. Optimum temperature for sporangial formation was 3$0^{\circ}C$, and zoospores were mostly released at $25^{\circ}C$ from the sporangia. Sporangia were more produced in C/Z solution with pH 5. 0~6.$0^{\circ}C$ than sterilized distilled water (DSW) and distilled water (DW), and zoospores were also released much more than other solutions. Eleven strawberry cultivars such as Reiko, Hokowase, Eyeberry, Akaneko, Sistakara, Toyonoka, Nyoho, Sulhong, Suhong, Myhong and Wonkyo #3104 revealed the disease incidence up to 88.9~100% by the leaf inoculation with mycelial disk. However, Nyoho and Suhong showed higher level of resistance against the pathogen by root inoculation.

• 식물병연구
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• 제10권1호
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• pp.17-20
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• 2004

2003년 8월 청도시험장의 화분재배한 일일초에서 잎, 꽃, 꼬투리 및 줄기가 검게 시들고 말라죽는 증상으로부터 병원균을 분리$.$동정한 결과 Phytophthora nicotianae로 동정되었다 병원균의 형태적 특성은 뚜렷한 유두돌기를 가지고 비탈락성인 원형 혹은 난형의 유주자낭을 형성하였고, 크기는 31.0${\times}$38.0$\mu\textrm{m}$였고 다량의 후막포자를 형성하였으며 크기는 평균 직경이 30.5 $\mu\textrm{m}$였다 유성생식형은 자웅이주로 Al mating type이 관찰되었고 난포자의 크기는 직경 23.1 $\mu\textrm{m}$였다. 균사의 생육적온은 25∼3$0^{\circ}C$였다. 이상과 같이 국내 최초의 P. nicorianae에 의한 일일초 역병의 발생을 보고하는 바이다.