• 한국식물병리학회지
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• 제13권2호
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• pp.129-131
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• 1997

Occurrence of brown rot was observed on imported orange fruits, and irregular brown spots were appeared as an intial symptom. White colored mycelia were developed rapidly on the surface of the fruits under the humid condition and resulted in rotting of the fruits. The causal organism of brown rot of orange was identified as Phytophthora citrophthora. Most sporangia were nondeciduous, papillate, ovoid, and measured 25.5~51.5$\times$17.9~34.7 ${\mu}{\textrm}{m}$ in size. P. citrophtora was pathogenic on Satsuma mandarin as well as orange. Symptoms were produced 3~7 days after artificial inoculation of sporangia and mycelia mixture on the fruits of orange and Satsuma mandarin, which were similar to those on the naturally infected fruits.

• 한국약용작물학회지
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• 제23권2호
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• pp.150-154
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• 2015

Physiological disorders such as symptoms in leaf colored with brown spots are so many occurred in ginseng garden cultivated with paddy soil. This study was carried out to inhibit the symptoms of brown-colored leaf in 3-year-old ginseng by fertilizing calcium hydroxide [$Ca(OH)_2$] of 100 ~ 400 kg per 10a on paddy soil before transplant of seedling. Soil pH was rapidly increased, while Fe was decreased in soil by the increase of application level of calcium hydroxide. Soil pH was increased from 4.53 to 6.18 when calcium hydroxide was fertilized at level of 100kg per 10a. The content of Fe in ginseng leaf was decreased more than the control by fertilizing calcium hydroxide in soil. Ratio of brown-colored leaf and plant height and leaf area were decreased by the increase of calcium hydroxide. Ratio of survived root and yield of root showed the peak at the application level of 100 kg per 10a, and both of them were gradually decreased by the increase of calcium hydroxide. The decrease of missing plant rate above the application level of 200 kg per 10a had a negative effect on the decrease of yield of root.

• 한국약용작물학회지
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• 제22권1호
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• pp.32-37
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• 2014

To study the cause of physiological disorder in leaf of ginseng cultivated at paddy soil, the degree of brown-colored symptom (BCS) and the contents of inorganic matter in leaf were investigated by irrigating the solution of ferric and ferrous iron of 0.1 ~ 2.0%, and citric acid of 1.0 ~ 4.0% on bed soil, respectively. Ratio of BCS by variety was as high as 85.0% in Yoenpoong, while it was as low as 5.4%, 7.5% in Chunpoong and Hwangsook, respectively. The contents of inorganic matter of leaf in Yoenpoong were lower in $P_2O_5$, Ca, and Mg, while it were higher in K, Fe, and Mn than other variety. Iron solution caused BCS more distinctly when each ferric and ferrous iron were dissolved with 1.0% citric acid than when each iron was dissolved without citric acid. Ferric iron caused BCS more effectively than ferrous iron. BCS occurred in 4.0% citric acid was as same as 2.0% ferric iron mixed with 1.0% citric acid. Low $P_2O_5$ and high Fe content in leaf appeared in both of artificial and natural symptoms. We concluded that excessive Fe uptake caused BCS to leaf because the solubility of iron was increased in condition of low soil pH.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.98.2-99
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• 2003

Bacterial canker of sweet cherry (Prunus cerasus L.) was observed in farmers' orchard in Goesan, Chungbuk in 2003. Typical canker symptom occurred on the branches or twigs of sweet cherry in early spring and bacterial exudates oozed out of the cracked barks of diseased trees. Watersoaked brown symptom appeared on the leaves and severe infection caused thorough defoliation on the branches or twigs of sweet cherry. When cut the severely infected branches or twigs, irregular and rusty-colored symptoms in sapwood and heartwood were clearly found, indicating that they could serve as specific symptoms of bacterial canker of sweet cherry. The gram negative, aerobic bacterium isolated from the lesion produced fluorescent pigments on King's B agar medium but did not grow at 37$^{\circ}C$ The bacterium formed Levan-type colonies, and showed negative reactions in oxidase reaction, arginine dihydrolysis test, and pectolytic activity Based on the biochemical and pathological characteristics, the causal organism was identified as Pseudomonas syringae pv. morsprunorum. This is the first report on bacterial canker of sweet cherry in Korea.

• 식물병연구
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• 제27권2호
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• pp.66-69
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• 2021

2020년 경상북도 상주시 감 과수원에서 갈색고약병이 발생하였다. 병징은 처음에 자갈색 내지 암갈색의 균사체가 가지 표면 일부분에 들러붙어 있다가 점차 균사체들이 자라면서 큰 덩어리로 합쳐져 결국엔 가지를 완전히 둘러싸였다. 균총의 색깔은 처음에 흰색이고 배양기간이 경과됨에 따라 배지 표면에 갈색의 균사가 많이 형성되었다. 균사생육 적온은 30℃이었다. rDNA의 complete internal transcribed spacer 영역의 염기서열을 분석하였고, 분석된 염기서열(564 bp)을 BLASTN 프로그램으로 확인한 결과, Septobasidium속(GenBank accession nos. HQ267951, HQ267959)과 99%의 상동성을 나타내었다. 또한, Septobasidium broussonetiae (HM209416)와 92%, Septobasidium bogoriense (HM209414)와 91%의 상동성을 나타내었다. 이와 같이 감에서 발생한 병징과 병원균의 균학적 특징을 기초로 하여 이 병을 Septobasidium속에 의한 감 갈색고약병으로 명명하고자 제안한다.

• The Plant Pathology Journal
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• 제18권3호
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• pp.161-164
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• 2002

Colletotrichum musae was isolated from dark-brown anthracnose lesions on commercial banana (Musa sapientum L.) to establish the causal agent of the symptom. The fungus grew fast and produced white aerial mycelium on PDA. Acervuli developed abundantly on culture plates after incubation for 10 days at $25^{\circ}C$. Pinkish conidial masses were produced on the acervuli, which mostly coalesced together, Conidia were aseptate, hyaline, straight, ellipsoid to globose, and 14.5$\times$6.9 $\mu\textrm{m}$ in size. Black, clavate, round, or irregular-shaped appressoria measuring 8.8$\times$6.8 $\mu\textrm{m}$ were readily formed from germ tubes. Setae-like structures were not found either on the lesion or on the cultures. Sclerotia were also absent. Among the media, PDA medium was the best for mycelial growth. The optimum temperature for mycelial growth was $28^{\circ}C$, while the optimum pH ranged from pH 5.5 to 6.5. The isolates of C musae caused black necrotic lesions on banana fruits by needle-wound inoculation, and orange-colored spore masses were produced on the lesions. The fungus also caused discoloration on apple fruits inoculated.

• 한국균학회지
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• 제41권1호
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• pp.38-41
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• 2013

무화과 잿빛곰팡이병은 2010년부터 2011년에 아열대작목을 시범적으로 재배하고 있는 전북 농업기술원 하우스 포장에서 발병하였다. 잿빛곰팡이병은 11월경의 저온상태에서 발병이 심하였으며, 병원균은 갈색의 일부분으로 시작하여 점차 진전되어 후기에는 과실 전체가 잿빛곰팡이로 뒤덮였다. 잿빛곰팡이로 뒤덮인 과실은 갈색 솜털을 덮고 있는 모양이었으며, 육안으로도 곰팡이 포자를 쉽게 관찰할 수 있었다. 병원균에 감염된 과실은 처음에 갈색~암 갈색 수침상으로 부패하기 시작하였고, 잿빛곰팡이균사와 포자가 밀생하였다. 무화과 잿빛곰팡이병의 분생포자는 구형으로 $7.3-14.6{\times}6.8-11.1{\mu}m$이며, 무색으로 단세포이었다. 또한 수지상으로 분지한 분생자경위에 무수히 형성 하였다. 분생자경의 크기는 $15-33{\times}2{\mu}m$이며, 갈색 또는 투명한 색을 띄고 있었다. rDNA ITS 영역의 염기서열 분석결과 무화과 잿빛곰팡이병을 일으키는 병원균은 Botrytis cinerea로 등록된 GenBank accession number HQ171052, EU519210, HQ171053, FN812726, HM849615, EU563120 과 100% 일치하는 것으로 나타났다. 또한 Botrytis spp. 종간 비교에서도 B. cinerea와 같은 clade에 속함을 확인할 수 있었으며, 다른 group과는 57%의 similarity를 보였다. 따라서 무화과 잿빛곰팡이병을 일으키는 병원균을 분리배양하여 균학적 특성과 rDNA ITS영역의 염기서열을 분석한 결과 이미 보고된 B. cinerea와 일치하였다.

• 식물병연구
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• 제19권3호
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• pp.226-228
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• 2013

2012년 경상남도 진주시 농산물도매시장에 판매중인 감귤에서 분홍빛열매썩음병이 발생하였다. 병징은 감귤 과실 표면이 수침상으로 물러지고 썩으면서 그 위에 분홍빛 곰팡이가 많이 형성되었다. 균총의 색깔은 처음에 흰색이고 배양기간이 경과됨에 따라 배지 표면에 분홍빛의 분생포자가 많이 형성되었다. 균사생육 적온은 $25^{\circ}C$이었다. 분생포자의 모양은 서양배형이며 좌우 zigzag로 부착하며 성숙한 분생포자는 2세포로 되어 있으며 크기는 $12-26{\times}8-12{\mu}m$이었다. 분생자경은 균사표면에 직립으로 형성하고, 폭이 4-5 ${\mu}m$이고 무색이었다. rDNA의 complete internal transcribed spacer(ITS) 영역의 염기서열을 분석하였고, 분석된 염기서열(613 bp)을 BLASTN 프로그램으로 확인한 결과, Trichothecium roseum와 99%의 상동성을 나타내었다. 이와 같이 감귤에서 발생한 병징과 병원균의 균학적 특징을 기초로 하여 이 병을 Trichothecium roseum(Pers.) Link ex Gray에 의한 감귤 분홍빛열매썩음병으로 명명하고자 제안한다.

• 한국산림과학회지
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• 제49권1호
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• pp.6-10
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• 1980

오동나무 빗자루병(病)을 방제(防除)할 목적(目的)으로 병(病)든 오동나무 (6년생(年生), 흉고직경(胸高直径) 10~15cm)에 Oxytetracycline HCl을 수간주입(樹幹注入)하여 다음과 같은 결과(結果)를 얻었다. 1. 1979년(年) 5월(月)~9월(月)에 Oxytetracycline HCl 2g/0.1~2.0l를 수간주입(樹幹注入)한 결과(結果) 1980년(年) 9월(月) 현재(現在) 처리(処理)한 모든 나무에서 병징(病徵)이 억제(柳制)되고 수세(樹勢)가 회복(回復)되어 정상적(正常的)인 생육(生育)을 하였다. 2. 수간주입(樹幹注入)은 수액이동(樹液移動)이 활발(活溌)한 5~9월(月)에 실시(實施)하는 것이 방제효과(防除效果)가 좋았으며. 3~4월(月)에 실시(實施)한 것은 방제효과(防除效果)가 떨어졌다. 3. Oxytetracycline HCl의 저농도대량주입(低濃度大量注入) (2g/l~2l)과 고농도소량주입(高濃度小量注入) (2g /0.1~0.2l) 간(間)에는 방제효과면(防除效果面)에서 차이(差異)가 없었으며, 고농도소량주입(高濃度小量注入)에 소요(所要)되는 시간(時間)은 24시간(時間) 내외(內外)인데 비(比)해 저농도대량주입(低濃度大量注入)은 3~4일(日)이 소요(所要)되었다.