• 식물병연구
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• 제29권4호
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• pp.414-419
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• 2023

2023년에 강진 귀리 재배농가에서 종자흑변병이 의심되는 종자가 다수 관찰되었다. 흑변 증상을 보이는 귀리종자 132개를 선발하여 곰팡이 감염률을 조사한 결과, Alternaria속이 84%를 차지할 만큼 우점으로 검출되었고 Alternaria alternata로 동정되었다. 강진 재배농가의 같은 포장에서 2022년에 수확한 종자와 외관 및 품질을 비교한 결과, 명도를 나타내는 L값이 2023년의 귀리 종자에서 유의하게 낮게 나타났으며 종자 품질을 평가하는 전기전도도는 2023년 종자에서 유의적으로 높게 측정되어 종자의 활력에 차이가 있었다. 귀리 파이토알렉신으로 알려진 아베난쓰라마이드 함량은 2023년 종자에서 2022년에 비해 10배 정도 높게 분석되었다. 출수 후 수확하기 전 생식생장 기간에 해당하는 2023년 5월 강진의 한 달 평균 강수량은 2022년 5월에 비해 230배 많았고 평균 상대습도도 높아 A. alternata의 감염에 적합한 환경이 조성되어 종자흑변병이 발생하였을 것으로 생각되었다. 기후변화로 대발생할 수 귀리 병에 대한 모니터링과 함께 적극적인 방제 노력이 필요하리라 생각한다.

• 한국식물병리학회지
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• 제11권4호
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• pp.318-323
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• 1995

The effect of AF-toxin I produced by the strawberry pathotype of Alternaria alternata on the protein synthesis of susceptible strawberry protoplasts was examined by using the radiolabeled amino acids. The incorporation of the radiolabeled amino acids into newly synthesized proteins in the strawberry protoplasts was stimulated by the toxin treatment at relatively low concentrations (2.2$\times$10-11 to 2.2$\times$10-9 M), but not at higher concentrations (2.2$\times$10-8 to 2.2$\times$10-6 M). An one-dimensional SDS-polyacrylamide gel electrophoresis revealed no detectable differences in the proteins synthesized in both the toxintreated and untreated protoplasts. The susceptible strawberry protoplasts were treated with AF-toxin I and stained with Fluostain I to detect the extracellular polysaccharides. The toxin treatment induced the accumulation of extracellular polysccharides in a dose-dependent manner. These results indicate a transient activation of cellular metabolism in the susceptible cells by the toxin exposure.

• 농업생명과학연구
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• 제45권2호
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• pp.9-13
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• 2011

This study was carried out to control the disease of wood-cultivated ginseng(panax ginseng) using natural materials. Four fungi spices such as Pythium ultimum, Alternaria alternata, Fusarium oxysporum and Rhizoctonia solani which caused disease of the wood-cultivated ginseng were investigated. The infection of these fungi causes symptom on roots, stems and leaves. The leaves became dry and die. The disease caused by Pythium ultimum can be prevented by using friendly environmental materials like Chamaecyparis obtuse essential oil and Wormstop. Alternaria alternata and Fusarium oxysporum might be prevented by using wormstop extracted from Neem tree(Azadirachta indica). No substance tested effectively prevents the growth of Rhizoctonia solani.

• The Plant Pathology Journal
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• 제33권1호
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• pp.95-100
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• 2017

Fungicide-resistant Alternaria alternata impede the practical control of the Alternaria diseases in crop fields. This study aimed to investigate cytological fungicide resistance mechanisms of A. alternata against dicarboximide fungicide iprodione. A. alternata isolated from cactus brown spot was cultured on potato-dextrose agar (PDA) with or without iprodione, and the fungal cultures with different growth characteristics from no, initial and full growth were observed by light and electron microscopy. Mycelia began to grow from one day after incubation (DAI) and continued to be in full growth (control-growth, Con-G) on PDA without fungicide, while on PDA with iprodione, no fungal growth (iprodione-no growth, Ipr-N) occurred for the first 3 DAI, but once the initial growth (iprodione-initial growth, Ipr-I) began at 4-5 DAI, the colonies grew and expanded continuously to be in full growth (iprodione-growth, Ipr-G), suggesting Ipr-I may be a turning moment of the morphogenetic changes resisting fungicidal toxicity. Con-G formed multicellular conidia with cell walls and septa and intact dense cytoplasm. In Ipr-N, fungal sporulation was inhibited by forming mostly undeveloped unicellular conidia with degraded and necrotic cytoplasm. However, in Ipr-I, conspicuous cellular changes occurred during sporulation by forming multicellular conidia with double layered (thickened) cell walls and accumulation of proliferated lipid bodies in the conidial cytoplasm, which may inhibit the penetration of the fungicide into conidial cells, reducing fungicide-associated toxicity, and may be utilized as energy and nutritional sources, respectively, for the further fungal growth to form mature colonies as in Ipr-G that formed multicellular conidia with cell walls and intact cytoplasm with lipid bodies as in Con-G.

• The Plant Pathology Journal
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• 제26권1호
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• pp.80-82
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• 2010

A stem spot disease was observed on Gymnocalycium mihanovichii (Korean name: Bimoran), a scion of graftcactus, in major growing areas of Goyang and Eumseong, Korea during 2008 and 2009. Typical symptoms were initial blackish brown lesions produced mainly on areoles and scars of injured stem tissues, gradually becoming large black spots. A causal organism isolate CD2-7A isolated from the infected stems was identified as Alternaria alternata based on its morphological characteristics and confirmed by the DNA sequencing analysis of ITS, glyceraldehydes-3-phosphate dehydrogenase (gpd), and allergen Alt a1 (Alt a 1) genes. Artificial inoculation of the fungal isolate CD2-7A produced the same rot symptoms on the cactus stems, from which the same fungus was isolated and identified. This is the first report of the black spot caused by A. alternata in the grafted cactus.

• 한국식품위생안전성학회지
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• 제23권3호
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• pp.177-181
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• 2008

희나리 고추에서 분리한 곰팡이를 현미에 배양하여 실험동물(rat)에 투여하였을 때 Colletotrichum, Diaporthe, Diaporthopsis, Botryosphereia, Aspergillus, Fusarium의 경우 독성을 나타내지 않았으나 Alternaria alternata로 동정된 곰팡이는 독성을 나타내었다. A. alternata를 배양한 현미를 투여한 실험동물은 사료 섭취량이 상대적으로 낮았으며, 체중 감소를 보였고 2주안에 치사하였으며, 위, 소장, 간의 확대가 관찰되었다. Alternaria속 곰팡이는 17종이 분리되었으며 이들 중 8종은 고추즙과 현미에 배양하였을 때 모두 상당량의 tenuazonic acid를 생산하였고, 현미 배지에서만 alternariol과 alternariol monomethyl ether 독소가 추가로 소량 검출되었다. 건조 과정에서 곰팡이가 번식된 고추는 유해한 대사물의 존재 가능성이 있으므로 식품 안전을 위해 곰팡이 번식을 최대한 억제할 필요가 있다.

• Mycobiology
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• 제48권3호
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• pp.233-239
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• 2020

A small-spored Alternaria was found from black spots of storaged Koerle pear (Pyrus sinkiangensis), one of the economically important fruit in Xinjiang province, China. The morphology is similar to A. limoniasperae but obviously different in secondary conidiophores and conidial septa. A phylogenetic analysis using sequence datasets of ITS, GAPDH, TEF1, RPB2, Alt a1, OPA10-2, and EndoPG genes revealed that it belonged to the Alternaria alternata complex group. Pathogenicity tests illustrated that the fungus was the causal pathogen of black spot on Koerle pear fruit.

• 미생물학회지
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• 제48권4호
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• pp.325-327
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• 2012

먹물버섯 C. congregatus의 자가분해되는 자실체 조직에서 발현되는 chitinase (Chi2)가 식물병원성 균류인 A. alternata와 F. graminearum를 대상으로 고체배지와 액체배지에서 포자의 발아 및 균사 생장에 대하여 보이는 억제효과 실험을 수행하였다. 액체배지에서 $50{\mu}g/ml$의 Chi2 농도에서 A. alternata의 포자 발아가 90% 이상 억제되었고, $70{\mu}g/ml$의 농도에서 실험균류 모두 생장이 억제되었다. 고체배지에서 하루에 $6{\mu}g$씩 2회 더한 Chi2에 의하여 F. graminearum 균사 생장이 억제됨을 확인하였고, 이때 균사의 branching이 상대적으로 감소하였다.

• The Plant Pathology Journal
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• 제40권1호
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• pp.59-72
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• 2024

A comprehensive survey of mungbean-growing areas was conducted to observe leaf spot disease caused by Alternaria alternata. Alternaria leaf spot symptoms were observed on the leaves. Diversity of 50 genotypes of mungbean was assessed against A. alternata and data on pathological traits was subjected to cluster analysis. The results showed that genotypes of mungbean were grouped into four clusters based on resistance parameters under the influence of disease. The principal component biplot demonstrated that all the disease-related parameters (% disease incidence, % disease intensity, lesion area, and % of infection) were strongly correlated with each other. Alt a 1 gene that is precisely found in Alternaria species and is responsible for virulence and pathogenicity. Alt a 1 gene was amplified using gene specific primers. The isolated pathogen produced similar symptoms when inoculated on mungbean and tobacco. The sequence analysis of the internal transcribed spacer (ITS) region, a 600 bp fragment amplified using specific primers, ITS1 and ITS2 showed 100% identity with A. alternata. Potato virus X (PVX) -based silencing vector expressing Alt a 1 gene was constructed to control this pathogen through RNA interference in tobacco. Out of 50 inoculated plants, 9 showed delayed onset of disease. Furthermore, to confirm our findings at molecular level semi-quantitative reverse transcriptase polymerase chain reaction was used. Both phenotypic and molecular investigation indicated that RNAi induced through the VIGS vector was efficacious in resisting the pathogen in the model host, Tobacco (Nicotiana tabacum). To the best of our knowledge, this study has been reported for the first time.

• Mycobiology
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• 제48권3호
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• pp.240-244
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• 2020

Alternaria alternata JS-1623 is an endophytic fungus isolated from a stem tissue of Korean fir, Abies koreana. Ethyl acetate extracts of culture filtrates exhibited anti-inflammatory activity in LPS induced microglia BV-2 cell without cytotoxicity. Here we report a 33.67 Mb sized genome assembly of JS-1623 comprised of 13 scaffolds with N50 of 4.96 Mb, and 92.41% of BUSCO completeness. GC contents were 50.97%. Of the 11,197 genes annotated, gene families related to the biosynthesis of secondary metabolites or transcription factors were identified.