• 식물병연구
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• 제10권2호
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• pp.126-129
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• 2004

2002년 7월 전북지방에 야생하는 칡의 잎에 점무늬병이 발병하였다. 잎에 처음에는 작은 점무늬증상이 나타나고. 이 점무늬 주변에 황색의 halo가 형성되는 것이 전형적인 특징이었다. 병반들이 점차 확대되어 융합되어 잎 전체가 황색으로 변색되며 결국 낙엽이 된다. 병원균이 분리되었으며 본 병원균의 균사집락은 PDA 배지에서 밝은 회녹색에서 암갈색이었다. 분생포자는 대부분 단생이며 드물게 3-8개 포자가 연쇄상으로 형성되었다. 분생포자는 암갈색이며 긴 난형 또는 곤봉형이고 크기는 20-60${\times}$10-25 $\mu\textrm{m}$이었다. 격막은 4-8개의 횡격막과 1-2개의 종격막을 형성하였다. 칡의 잎에 발생한 병징과 본 병원균의 균학적 특징을 검정한 결과, 이 병을 Alternaria tenuissima에 의한 칡 점무늬병으로 명명하고자 제안한다.

• 식물병연구
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• 제21권4호
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• pp.330-333
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• 2015

In June 2013, we collected leaf spot disease samples of Datura metel from Gangneung, Gangwon Province, Korea. The symptoms observed were small circular to oval dark brown spots with irregular in shape or remained circular with concentric rings. We isolated the pathogen from infected leaves and cultured the fungus on potato dextrose agar. We examined the fungus morphologically and confirmed its pathogenicity according to Koch's postulates. The results of morphological examinations, pathogenicity tests, and the rDNA sequences of the internal transcribed spacer regions (ITS1 and ITS4), glycerol-3-phosphate dehydrogenase (G3PDH) and the RNA polymerase II second largest subunit (RPB2) gene sequence revealed that the causal agent was Alternaria tenuissima. To the best of our knowledge, this is the first report of leaf spot of D. metel caused by A. tenuissima in Korea as well as worldwide.

• 식물병연구
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• 제8권2호
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• pp.117-119
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• 2002

2002년 경상남도 남해군 창선면 잠두 재배포장에서 잎, 줄기, 꼬투리에 점무늬병이 심하게 발생하였다. 병징은 잎에 작은 둥근 점무늬가 나타나고 동심윤문을 형성하며 담갈색의 원형병반이 확대되면서 부정형으로 되고 괴사되면서 심할 경우 낙엽된다. 분생포자는 단생 또는 연쇄상으로 형성되며 모양은 긴타원형, 가늘고 긴 난형 또는 곤봉형으로 횡격막이 4~10개, 종격막이 1~2개가 있다. 색깔은 담황록색 또는 갈색이다. 크기는 25~61.3$\times$7.2~16.8$\mu\textrm{m}$ 이었다. 분생자병은 단생 또는 총생이며 담갈색이고, 크기는 18~113$\times$3~6 $\mu\textrm{m}$이었다. 균사생육 적온은 3$0^{\circ}C$이었다. 잠두 잎에 발생한 병징과 병원균의 균학적 특징을 검정한 결과, 이 병을 Alternaria tenuissima에 의한 잠두 점무늬병으로 명명하고자 제안한다.

• 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.

• Mycobiology
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• 제44권3호
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• pp.187-190
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• 2016

In July 2015, diseased leaves of black chokeberry (Aronia melanocarpa) were observed in Danyang and Gochang, Korea. The symptoms appeared as circular or irregular brown leaf spots, from which Alternaria tenuissima was isolated. The isolates were cultured on potato dextrose agar, and their morphological characteristics were observed under a light microscope. The colonies were whitish to ash colored. The pathogenicity test on healthy black chokeberry leaves produced circular brown spots, in line with the original symptoms. Molecular analyses of the ITS, GPD, RPB2, and TEF genes were conducted to confirm the identity of the pathogen. The phylogeny of the multi-gene sequences indicated that the causal agent was A. tenuissima. This study is the first report of A. tenuissima leaf spot on black chokeberry (A. melanocarpa).

• International Journal of Industrial Entomology and Biomaterials
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• 제20권1호
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• pp.1-5
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• 2010

The studies have been conducted to control the soil borne fungal pathogens viz, Fusarium solani (Mart) Sacc. and Alternaria tenuissima the incitants of root rot and die-back diseases on mulberry stem cuttings planted in the mulberry nurseries and also in established mulberry gardens ten plant extracts with 10% concentration except Lantana camara (undiluted) were tested through poisoned food technique and four biofungicides were also screened by dual culture method under in vitro conditions. Plant extract of Prosopis juliflora showed the maximum inhibition on the mycelial growth (81.2% over A. tenuissima and 80.0% over F. solani) and followed by L. camara (66.7% over A. tenuissima and 68.9% over F. solani). Among the antagonists Pseudomonas fluorescens and Trichoderma viride showed maximum inhibition on the mycelial growth of both pathogenic fungi. The promising plant extracts (P. juliflora and L. camara) and antagonists (P. fluorescens and T. viride) were tested against both the pathogenic fungi under in vivo conditions along with the existing popular chemical Mancozeb. All the tested plant products and bio-fungicides showed inhibitory effect on both fungi. But the maximum survival percentage of mulberry cuttings was recorded in the treatment with T. viride (95% against F. solani and 90% against A. tenuisssima) followed by P. fluorescens (90% against both fungi) and T. harzianum (80% against F. solani and 85% against A. tenuisssima). Incase of the treatments with plant extracts and chemical fungicide the P. juliflora (60% against F. solani and 55% against A. tenuisssima) showed higher survival percentage and followed by L. camara (55% against F. solani and 50% against A. tenuisssima) and Mancozeb (55% against both fungi). In case of control only 10% of survival was recorded in F. solani inoculated cuttings and 15% survival in A. tenuissima inoculated cuttings.

• Mycobiology
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• 제43권2호
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• pp.93-106
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• 2015

Alternaria species are common saprophytes or pathogens of a wide range of plants pre- and post-harvest. This review considers the relative importance of Alternaria species, their ecology, competitiveness, production of mycotoxins and the prevalence of the predominant mycotoxins in different food products. The available toxicity data on these toxins and the potential future impacts of Alternaria species and their toxicity in food products pre- and post-harvest are discussed. The growth of Alternaria species is influenced by interacting abiotic factors, especially water activity ($a_w$), temperature and pH. The boundary conditions which allow growth and toxin production have been identified in relation to different matrices including cereal grain, sorghum, cottonseed, tomato, and soya beans. The competitiveness of Alternaria species is related to their water stress tolerance, hydrolytic enzyme production and ability to produce mycotoxins. The relationship between A. tenuissima and other phyllosphere fungi has been examined and the relative competitiveness determined using both an Index of Dominance ($I_D$) and the Niche Overlap Index (NOI) based on carbon-utilisation patterns. The toxicology of some of the Alternaria mycotoxins have been studied; however, some data are still lacking. The isolation of Alternaria toxins in different food products including processed products is reviewed. The future implications of Alternaria colonization/infection and the role of their mycotoxins in food production chains pre- and post-harvest are discussed.

• 한국자원식물학회지
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• 제30권4호
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• pp.343-351
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• 2017

401종의 식물에서 얻은 메탄올 추출물 662개를 식물 병원성 곰팡이[딸기잿빛곰팡이병균(Botrytis sp.), 고추탄저병균(Colletotrichum sp.), 작약점무늬병균(Alternaria sp.) 및 작약검은뿌리썩음병균(Cylindrocarpon sp.)]에 대한 분생포자의 발아억제 활성을 microdilution assay로 측정하였다. 검정에 사용한 추출물 중에서 36종의 추출물이 1종 이상의 곰팡이에 대하여 억제활성을 보였다. 짚신나물, 고본, 족도리풀, 일천궁, 백선 및 목향의 뿌리, 능소화의 잎가지, 감초의 지상부, 뽕나무의 가지 추출물은 식물의 지상부 조직에서 발병하는 균(Botrytis sp., Colletotrichum sp. 그리고 Alternaria sp.)과 뿌리에 발병하는 균(Cylindrocarpon sp.)의 포자발아를 모두 억제하는 항균활성을 보여 주어 이들 추출물의 항균범위가 넓은 것으로 나타났다. 각각의 곰팡이 대한 추출물의 억제활성을 보면, 뽕나무의 가지와 고삼의 뿌리 추출물은 1,250 mg/L에서 딸기잿빛곰팡이병균의 포자발아를 완전히 억제하였다. 고추탄저병균의 포자발아억제에 가장 강한 추출물은 홀아비꽃대의 뿌리였으며, $1,250{\mu}g/ml$에서 완전히 억제하였다. 작약점무늬병균에 가장 강한 억제활성을 나타낸 추출물은 감초의 지상부였으며, $625{\mu}g/ml$에서 포자의 발아를 100% 억제하였고, 새모래덩굴의 뿌리와 뽕나무 가지 추출물은 $1,250{\mu}g/ml$에서 억제하였다. 작약검은뿌리썩음병균에 가장 강한 억제활성을 나타낸 추출물은 감초의 지상부와 목향의 뿌리였으며, $1,250{\mu}g/ml$에서 포자발아를 억제하였다.

• Mycobiology
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• 제28권4호
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• pp.185-189
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• 2000

The antifungal activity of methanolic extracts of Centella asiatica and Andrographis paniculata leaves was observed against fourteen fungi, viz., Alternaria alternata, A. brassicae, A. brassicicola, A. solani, A. tenuissima, Cercospora blumae, Curvularia lunata, C. penniseti, and Drechslera monoceras, D. oryzae, D. turitica, Fusarium albizziae and F. udum. Different concentrations of the methanolic extract (1000, 2000, 3000, 5000, 7000, 10000ppm) were used. The effect of mixed leaf extract (1500 ppm of C. asiatica + 1500 ppm of A. paniculata) and its 1:2 ad 1:4 dilutions were also studied. The individual extracts of both the plants showed significant inhibitory effect on spore germination of all the fungi tested. F. udum, F. albizzae, D. oryzae, D. turtica, and D. monoceras were particularly sensitive to these extracts. In general, the extract of C. asiatica showed a higher inhibitory effect in all concentrations against all the fungi as compared to A. paniculata, except for A. brassicae A. solani, D. oryzae, D. penniseti and Curvularia sp. The inhibitory effect of extracts increased when they were used in combination with or without dilutions against A. brassicicola, A. solani A. brassicae, A. alternata, A. tenussima, C. blumae, C. lunata, C. penniseti and Curvularia species. Higher efficacy of active ingredient of these extracts under field condition is envisaged against plant pathogens.

• 한국환경농학회지
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• 제37권3호
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• pp.221-228
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• 2018

BACKGROUND: Spoilage fungi can reduce the shelf life of fresh fruits and cause economic losses by lowering quality. Especially, mulberry fruits have high sensitivity to fungal attack due to their high water content (> 70%) and soft texture. In addition, the surface of these fruits is prone to damage during harvesting and postharvest handling. However, any study on postharvest spoilage fungi in mulberry fruit has not been reported in Korea. This study aimed to examine the spoilage fungi occurring in mulberry fruits during storage after harvest. METHODS AND RESULTS: In this study, we isolated postharvest spoilage fungi from mulberry fruits stored in refrigerator (fresh fruits) and deep-freezer (frozen fruits) and identified them. In the phylogenetic analysis based on comparisons of the ITS rDNA sequences, the 18 spoilage fungi isolated from mulberry fruits and the 25 reference sequences were largely divided into seven groups that were subsequently verified by high bootstrap analysis of 73 to 100. Alternaria spp. including A. alternate and A. tenuissima, were the most frequently isolated fungi among the spoilage isolates: its occurrence was the highest among the 18 isolates (38.9%). CONCLUSION: The findings of this study will be helpful for increasing the shelf life of mulberry fruits through the application of appropriate control measures against infection by spoilage fungi during storage.