• 식물병연구
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• 제24권4호
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• pp.292-301
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• 2018

Alternaria leaf spot disease has been a concern during a tomato production in greenhouse. In vitro antifungal activities of vapours of four plant essential oils, cinnamon oil, fennel oil, origanum oil and thyme oil, were investigated during in vitro conidial germination and mycelial growth of Alternaria alternata causing the tomato leaf spots to find eco-friendly alternatives for chemical fungicides. The four plant essential oils showed different antifungal activities against in vitro conidial germination of A. alternata in dose-dependent manners, and cinnamon oil vapour was most effective to suppress the conidial germination. The four plant essential oils showed similar antifungal activities against the in vitro mycelial growth of A. alternata in dose-dependent manners, but low doses of thyme oil vapour slightly increased in vitro mycelial growth of A. alternata. Necrotic lesions on the A. alternata-inoculated tomato leaves were reduced differently depending on kinds and concentrations of plant essential oils. Delayed conidial germination and germ-tube elongation of A. alternata were found on the tomato leaves treated with cinnamon oil and origanum oil vapours at 6 hpi. These results suggest that volatiles from cinnamon oil and origanum oil can be provided as alternatives to manage Alternaria leaf spot during the tomato production eco-friendly.

• 식물병연구
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• 제14권1호
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• pp.68-70
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• 2008

2006년 6월 전남 순천과 고흥지역의 농가에서 재배되고 있는 참다래 잎에 갈색 점무늬 증상이 나타나기 시작하여 점차 짙은 갈색의 둥근 무의로 확대되었고, 심할 경우에는 생육기 동안에도 낙엽을 초래하였다. 둥근 무늬병반에서 일관성 있게 분리된 Alternaria sp.를 순수배양시켜 관찰한 균학적 특징과 참다래 잎에 상처접종에 의한 확인된 병원성을 토대로 Alternaria alternata (Fr.) Keissler에 의한 참다래 갈색둥근무늬병으로 동정하였다. A. alternata는 감자한천배지에서 짙은 회색 균총을 형성하였고 분생포자를 다량 형성하였다. 담갈색 또는 금색의 분생포자는 난형 또는 역곤봉 형태를 하며, 분생포자경 위에 보통 5개 이상 사슬모양으로 형성되는데, 횡격막이 $3{\sim}5$개, 종격막이 $1{\sim}2$개가 있고, 분생포자의 크기는 $16.5{\sim}42.1{\times}6.7{\sim}19.5\;{\mu}m$, 분생포자경의 길이는 $8.6{\sim}112.7\;{\mu}m$였다. 이상과 같이 국내 최초로 A. alternata에 의한 참다래 갈색둥근무늬병의 발생을 보고하는 바이다.

• 한국응용곤충학회지
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• 제24권3호
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• pp.129-133
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• 1985

Effect of some physical and chemical factors on germination of conidia of Alternaria alternata (Fries) Keissler causing fruit rot of apple was investigated. The germination was maximum at $30^{\circ}C$, 100 per cent RH and at 5.5 pH Syllit, amongst the 11 fungicides and Planofix, amongst the 5 growth regulators caused maximum inhibition of conidial germination.

• International Journal of Industrial Entomology and Biomaterials
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• 제38권1호
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• pp.6-13
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• 2019

In the present study, we investigated the antifungal activity of methanol and ethanol extracts of different parts (leaves, twigs, and root bark) of mulberry plant against Alternaria alternata and Fusarium sp. Among them, the methanol and ethanol extracts of mulberry root bark exerted the highest inhibitory activity against the mycelial growth of A. alternata ($70.6{\pm}1.6$ to $80.8{\pm}6.7%$ and $58.7{\pm}0.0$ to $80.8{\pm}6.7%$, respectively) and Fusarium sp. ($15.5{\pm}2.7$ to $39.3{\pm}3.4%$ and $26.4{\pm}2.7$ to $47.6{\pm}4.8%$, respectively). In contrast, the methanol and ethanol extracts from mulberry leaves and twigs did not suppress the mycelial growth of these fungal species. Importantly, the methanol and ethanol extracts of mulberry leaves tended to even accelerate the mycelial growth of A. alternata and Fusarium sp. Therefore, the results of this study indicate that methanol and ethanol extracts of mulberry root bark can be used as control agents against A. alternata and Fusarium sp.

• The Plant Pathology Journal
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• 제22권1호
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• pp.11-15
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• 2006

Five seed samples of carrot were tested to detect Alternaria spp. by blotter method. A. alternata and A. radicina were detected from all the seed samples as high as $25.8-70.5\%$ and $37.5-63.5\%$, respectively. A. dauci was detected from four seed samples as low as $0.5-7.5\%$. The three Alternaria spp. were detected from the pericarp and the seed coat and endosperm of the carrot seeds but not from the embryo by component plating test. A. alternata and A. radicina were much more detected from the pericarp than the seed coat and endosperm. A. dauci was detected from the pericarp and the seed coat and endosperm at similar rate. The seed sample which was most severely infected with A. radicina showed the lowest rate of germination in the test on top of paper (TP). In the TP test, differences in total infection rate of A. radicina and A. dauci of the seed samples were very closely correlated with those in incidence of seedling rot on the seed samples. However, there was no correlation between infection rate of A. alternata and rate of germination or seedling rot of the seed samples. Soil test for seedling growth revealed that there was no correlation between differences in total infection rate of A. radicina and A. dauci and those in rate of normal seedlings of the seed samples.

• 식물병연구
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• 제30권1호
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• pp.13-19
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• 2024

In July 2022 and 2023, black mold symptoms were observed sporadically on fruits of sweet pepper (Capsicum annuum) plants grown in a greenhouse located in Suwon, Korea. The incidence of black mold on the fruits was 5-24% (average 14.8%) in variety SP-504 (yellow and elongate type) and 1-8% (average 5%) in variety SP-505 (red and round type) investigated. Four single-conidium isolates of Alternaria sp. obtained from the diseased fruits were identified as Alternaria alternata based on the morphological characteristics and molecular phyogenetic analyses. The isolates were tested for pathogenicity to sweet pepper fruits of varieties SP-504 and SP-505 through artificial inoculation. The isolates mostly induced large lesions on fruits of the two varieties in the wound inoculation, but only two isolates small lesions on fruits of the variety SP-504 in the non-wound inoculation. No lesions formed on fruits of the variety SP-505 in the non-wound inoculation. The pathogenicity tests revealed that susceptibility of sweet pepper fruits to the disease differs between the varieties. The symptoms induced by pathogenicity tests with the isolates were similar to those observed on fruits from the greenhouse investigated. This is the first report of A. alternata causing black mold on sweet pepper fruits in Korea.

• 식물병연구
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• 제9권3호
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• pp.159-161
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• 2003

잇꽃 잎점무늬병이 2000년 경북 의성군 일대의 잇꽃재배농가포장에서 발생하였다. 조사지역의 발병엽율은 30% 내외였다. 병징은 발아 후에 떡잎에 갈색의 반점을 만들어 완전히 전개하지 못하여 갈변하여 갈라지는 증상과 생육중기이후 잎에 갈색의 반점과 주위에 노랗게 탈색되는 병징이 생기고 이후 중앙부위는 회색 또는 검은 색으로 확대되면서 주위의 노란 변색부위도 확대되었고, 심해지면 전체가 갈색으로 고사하여 낙엽 되었다. Alternaria alternata의 균학적 특징은 분생자경의 길이는 20~110${\mu}m$; 포자의 크기가 10~20 ${\times}$ 30~60 ${\mu}m$이었으며, 격벽수는 3~8개; beak의 길이는 5~35 ${\mu}m$로 짧은 형태의 포자가 연쇄상으로 붙어 있었다. A.carthami는 분생자경의 길이는 40~80${\mu}m$; 포자의 크기가 10~15 ${\times}$40~100 ${\mu}m$ 이었으며, 격벽수는 4~10개; beak의 길이는 30~65 ${\mu}m$로 대부분의 포자는 하나씩 분리되어 있었다. 잇꽃의 점무늬 병징에서 분리한 병원균의 균학적 특징을 Joseph(1994)의 보고와 비교해본 결과 생육중기에 분리된 균은 A. carthami이었으며, 떡잎과 노쇄한 잎의 병반에서 분리한 병원균은 A. alternata로 동정되었다. 그러므로 이 병을 A. carthami와 A. alternata에 의한 잇꽃의 잎점무늬병으로 명명할 것을 제안한다.

• 식물병연구
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• 제10권3호
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• pp.183-187
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• 2004

2002년 경남 창원시 동읍 단감 저온 저장고에 저장중인 과실에서 검은점무의 증상이 심하게 발생하였다. 병징은 과실표면에 검은색 둥근 반점이 생기고 병반부위가 확대되면서 그 위에 암갈색의 곰팡이를 형성한다. 병반부위를 절단해 보면 감염된 표피에서부터 시작하여 과육내부까지 갈색으로 변색되고 스폰지 모양으로 부패되어 상품성이 전혀 없다. 병원균의 분생포자는 난형, 곤봉형, 서양배형이고 드물게 타원형도 있으며 횡격막이 3∼5개, 종격막이 1∼2개 있다. 색깔은 연한 갈색 또는 금색을 띄는 갈색이고 크기는 12∼46${\times}$6∼12$\mu\textrm{m}$이었다. 분생포자경은 연한 담갈색이고, 크기는 42∼95${\times}$3∼5 $\mu\textrm{m}$이었다. 균사생육적온은 25∼3$0^{\circ}C$이었다. 단감 저장중 과실에 발생한 병징과 병원균의 균학적 특징을 조사한 결과, 이 병을 Alternaria alternata (Fr.) Keissler에 의한 단감 검은점무의병으로 명명하고자 제안한다.

• Current Research on Agriculture and Life Sciences
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• 제17권
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• pp.7-13
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• 1999

고추의 뿌리에 서식하고 있는 근권미생물을 30여종 분리하여 고추 검은 곰팡이병원균 A. alteranta에 길항하는 미생물을 분리한 결과 분리주 No. J-24 균주가 가장 길항력이 우수하였으며 Bacillus subtilis로 동정되었다. B. subtilis J-24는 검은곰팡이병균(Alternaria alternata)에 대해서는 생육저지 효과가 99%로 나타났으며, 그외 갯빛곰팡이병균(Botrytis cinerea), 역병균(Phytophthora capsici), 잘록병균(Pythium ultimum), 탄저병균(Colletotrichum gloeosporioides), 겹무늬병균(Stemphylium botryosum)에도 생육저지효과를 강하게 나타내었다. 고추 유묘의 생장활력은 미생물제제가 첨가된 상토가 일반 상토 보다 엽면적이 15%, 줄기길이가 12%, 뿌리길이가 12% 증가하였고 전체 건물중이 약 13% 증가하여 고추유묘의 생장활력이 증가되었다.

• The Plant Pathology Journal
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• 제37권4호
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• pp.329-338
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• 2021

Alternaria leaf blight is one of the most common diseases in watermelon worldwide. In Korea, however, the Alternaria species causing the watermelon leaf blight have not been investigated thoroughly. A total of 16 Alternaria isolates was recovered from diseased watermelon leaves with leaf blight symptoms, which were collected from 14 fields in Korea. Analysis of internal transcribed spacer (ITS) region, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and RNA polymerase II second largest subunit (RPB2) were not competent to differentiate the Alternaria isolates. On the contrary, analysis of amplicon size of the histone H3 (HIS3) gene successfully differentiated the isolates into three Alternaria subgroups, and further sequence analysis of them identified three Alternaria spp. Alternaria tenuissima, A. gaisen, and A. alternata. Representative Alternaria isolates from three species induced dark brown leaf spot lesions on detached watermelon leaves, indicating that A. tenuissima, A. gaisen, and A. alternata are all causal agents of Alternaria leaf blight. Our results indicate that the Alternaria species associated watermelon leaf blight in Korea is more complex than reported previously. This is the first report regarding the population structure of Alternaria species causing watermelon leaf blight in Korea.