• 제목/요약/키워드: Alternaria

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가지과 작물에서 분리한 Alternaria 속 균의 형태적, 분자생물학적 특징 (Morphological and Molecular Characterization of Alternaria Isolates from Solanaceous Crops)

  • 유승헌;조혜선;김병련;박명수
    • 한국균학회지
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    • 제31권2호
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    • pp.103-113
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    • 2003
  • 국내의 가지과 작물에서 분리한 Alternaria 25 균주를 공시하여 분생포자의 형태적 특징을 조사하였고 A. solani와 A. tomaotphilad의 대표균주와 비교하였다. 분리균주 중 형태적으로 구별되는 몇 균주들과 대표균주를 공시하여 감자, 토마토, 가지, 고추에 대한 병원성 검정을 실시하였다. 대표균주를 포함한 Alternaria 17개 균주를 공시하여 ITS 영역과 histone h3 유전자의 염기서열분석, URP (universal rice primer)에 의한 핵산지문분석을 실시하였다. Alternaria 균주들은 분생포자의 형태적 특징에 의하여 A. tomaotophila(ATO), A. solani(ASO) 및 미동정의 Alternaria sp.(ASP)의 group으로 나눌 수 있었고 A. solani(ASO)는 분생포자 부리(beak)의 특징에 의하여 다시 ASO(1)과 ASO(2)의 2 type으로 나눌 수 있었다. ATO와 ASO 균주들은 실험에 사용한 감자, 토마토, 가지, 고추에 모두 병원성이 있었고 ATO 균주는 특히 토마토에 강한 병원성이 있었으나, ASP 균주는 감자에만 병원성이 있었다. 이 연구에서 사용한 molecular marker중 ITS와 histon H3 유전자의 염기서열 분석은 4개의 형태적 group을 명확히 구분할 수 없었지만, URP-PCR 핵산지문분석법은 이들 group을 명확히 구분할 수 있었다. 분생포자의 형태, 병원성검정, 분자생물학적 특징을 종합할 때 토마토 겹무늬병에 관여하는 A. tomatophila는 감자겹둥근무늬병에 관여하는 A. solani와 뚜렷이 구분할 수 있었다. 또한 감자에서 분리한 Alternaria sp.(ASP)는 A. solani(ASO)와 형태적으로 유사하였지만 분생포자의 폭이 두껍고 부리(beak)가 작다는 점에서 ASO와 구별되었으며 가지과 작물에서 보고된 바 없는 신종으로 추정되었다.

Alternaria mycotoxins and its incidence in fruits and vegetables

  • Patriarca, Andrea
    • 한국균학회소식:학술대회논문집
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    • 한국균학회 2018년도 춘계학술대회 및 임시총회
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    • pp.13-13
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    • 2018
  • Alternaria is a ubiquitous fungal genus, widely distributed in the environment and a range of different habitats. It includes both plant pathogenic and saprophytic species, which can affect crops in the field or cause post-harvest spoilage of plant fruits and kernels. Numerous Alternaria species cause damage to agricultural products including cereal grains, fruits and vegetables, and are responsible for severe economic losses worldwide. Most Alternaria species have the ability to produce a variety of secondary metabolites, which may play important roles in plant pathology as well as food quality and safety. Alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), tentoxin (TEN) and altenuene (ALT) are considered the main Alternaria compounds thought to pose a risk to human health. However, food-borne Alternaria species are able to produce many additional metabolites, whose toxicity has been tested incompletely or not tested at all. Both alternariols are mutagenic and their presence in cereal grain has been associated with high levels of human esophageal cancer in China. TeA exerts cytotoxic and phytotoxic properties, and is acutely toxic in different animal species, causing hemorrhages in several organs. The possible involvement of TA in the etiology of onyalai, a human hematological disorder occurring in Africa, has been suggested. Altertoxins (ALXs) have been found to be more potent mutagens and acutely toxic to mice than AOH and AME. Other metabolites, such as TEN, are reported to be phytotoxins, and their toxicity on animals has not been demonstrated up to now. Vegetable foods infected by Alternaria rot are obviously not suitable for consumption. Thus, whole fresh fruits are not believed to contribute significantly with Alternaria toxins to human exposure. However, processed vegetable products may introduce considerable amounts of these toxins to the human diet if decayed or moldy fruit is not removed before processing. The taxonomy of the genus is not well defined yet, which makes it difficult to establish an accurate relationship between the contaminant species and their associated mycotoxins. Great efforts have been made to organize taxa into subgeneric taxonomic levels, especially for the small-spored, food associated species, which are closely related and constitute the most relevant food pathogens from this genus. Several crops of agricultural value are susceptible to infection by different Alternaria species and can contribute to the entry of Alternaria mycotoxins in the food chain. The distribution of Alternaria species was studied in different commodities grown in Argentina. These food populations were characterized through a polyphasic approach, with special interest in their secondary metabolite profiles, to understand their full chemical potential. Alternaria species associated with tomato, bell pepper, blueberry, apples and wheat cultivated in Argentina showed a surprisingly high metabolomic and mycotoxigenic potential. The natural occurrence of Alternaria toxins in these foods was also investigated. The results here presented will provide background for discussion on regulations for Alternaria toxins in foods.

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AM-toxin을 이용(利用)한 사과점무늬낙엽병균(Alternaria mali)의 공기중(空氣中) 밀도(密度) 조사(調査) (The Use of AM-toxin in Monitoring the Numbers of Air-borne Spores of Alternaria mali Causing Leaf Spot in Apple Orchards)

  • 유승헌;심형권;박종성
    • 한국응용곤충학회지
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    • 제26권4호
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    • pp.273-275
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    • 1987
  • Changes in the numbers of air-borne spores of Alternaria mali causing the Alternaria leaf spot of apple were investigated in apple orchards, by monitoring their AM- toxin(host-specific toxin) producing ability. Most of the air-borne Alternaria in apple orchards were not AM-toxin producers. In culture, only about 2% of Alternaria isolates from a commercially managed apple orchards produced the toxin that was highly toxic only to susceptible leaves.

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Alternaria속 균에 있어서 진균독소 생성균의 분포 (Distribution of Mycotoxin-Producing Isolates in the Genus Alternaria)

  • 이향범;유승헌
    • 한국식물병리학회지
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    • 제11권2호
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    • pp.151-157
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    • 1995
  • 국내에서 분리한 20종의 Alternaria 277개 균주를 사용하여 Alternaria 진균소독인 altenuene(ALT), altertoxin-I(ATX-I) 및 tenuazonic acid(TA)의 in vitro에서의 생성능과 그 분포를 조사하였다. 각 사용균주를 200g의 살균된 쌀배지에 접종하여 $25^{\circ}C$에서 3주간 배양하였다. Alternaria 배양체들을 methanol로 추출하고 용매분획과 TLC 및 HPLC분석을 통하여 순화하였다. A. alternata와 그와 형태적으로 유사한 A. kikuchiana, A. longipes 및 A. mail는 비록 종간 및 종내의 균주간에 생성량의 차이는 매우 다양하였지만 TA를 비롯한 5종의 진균독소를 모두 생성하였다. A sesami와 A. sesamicola는 4종의 진균독소(AOH, AME, ALT, ATX-I)를 생성하였고 A. cucumerina, A. dauci, A. macrospora, A. porri, A. solani, A. tagetica와 A. zinniae와 같은 대형분생포자와 긴 beak를 형성하는 7종의 Alternaria균들은 AOH와 AME만을 생성하였다. A. brassicicola, A. helianthi, A. panax, A. radicina 및 A. raphani등 5종의 Alternaria는 5종의 진균 독소를 모두 생성하지 않았다.

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Taxonomic Studies on Alternaria in Korea(1)

  • Cho, Hye-Sun;Kim, Byung-Ryun;Yu, Seung-Hun
    • Mycobiology
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    • 제29권1호
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    • pp.27-42
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    • 2001
  • The taxonomy of the Alternaria spp. has been a subject, of controversy because of their high variability in conidial morphology and polymorphism displayed even in pure cultures. The published Korean literature on the genus Alternaria is scattered and fragmentary, and pertains to about 25 species with special emphasis on occurrence and pathogenicity, but mycological studies on this group of fungi are insufficient. This is the first series of detailed and consolidated account of Korean species of Alternaria, which includes 11 species; viz., Alternaria brassicae, A. brassicicola, A. cinerariae, A. dauci, A. dianthi, A. dianthicola, A. helianthi, A. helianthinffciens, A. iridicola, A. japonica and A. protenta. Detailed diagnostic descriptions, specific characterizations, taxonomic discussions and illustrations for each species are presented.

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The Incidence of Alternaria Species Associated with Infected Sesamum indicum L. Seeds from Fields of the Punjab, Pakistan

  • Nayyar, Brian Gagosh;Woodward, Steve;Mur, Luis A.J.;Akram, Abida;Arshad, Muhammad;Naqvi, S.M. Saqlan;Akhund, Shaista
    • The Plant Pathology Journal
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    • 제33권6호
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    • pp.543-553
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    • 2017
  • Sesame (Sesamum indicum) is an important oil seed crop of Asia. Yields can be negatively impacted by various factors, including disease, particularly those caused by fungi which create problems in both production and storage. Foliar diseases of sesame such as Alternaria leaf blight may cause significant yield losses, with reductions in plant health and seed quality. The work reported here determined the incidence of Alternaria species infecting sesame seeds grown in the Punjab, Pakistan. A total of 428 Alternaria isolates were obtained from 105 seed samples and grouped into 36 distinct taxonomic groups based on growth pattern and morphological characters. Isolation frequency and relative density of surface sterilized and non-surface sterilized seeds showed that three isolates (A13, A47 and A215) were the most common morphological groups present. These isolates were further identified using sequencing of the Internal Transcribed Spacer (ITS) region of ribosomal DNA (rDNA) and the Alternaria major allergen gene (Alt a 1). Whilst ITS of rDNA did not resolve the isolates into Alternaria species, the Alt a 1 sequences exhibited > 99% homology with Alternaria alternata (KP123850.1) in GenBank accessions. The pathogenicity and virulence of these isolates of Alternaria alternata was confirmed in inoculations of sesame plants resulting in typical symptoms of leaf blight disease. This work confirms the identity of a major source of sesame leaf blight in Pakistan which will aid in formulating effective disease management strategies.

한국산 고추와 참깨에 발생하는 Alternaria의 종류와 이들의 진균독소 생성능력 (Incidence of Altermaria Species in Red Pepper and Sesame from Korea and Their Ability to Produce Mycotoxins)

  • 이향범;유승헌
    • 한국식물병리학회지
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    • 제11권1호
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    • pp.1-8
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    • 1995
  • Alternaria alternata and A. solani were identified from 130 Alternaria isolates obtained from red pepper fruits, and three species including A. alternata, A. sesami and A. sesamicola were detected from 150 isolates from sesame seeds. Among the 4 Alternaria species, A. alternata was the predominant fungus from both plants, having incidence of 95.4% in red pepper and 56.0% in sesame. Of the total 280 isolates, cultures on autoclaved rice of 75 isolates were tested for toxicity to 21-day-old virgin female rats. Out of 50 isolates of A. alternata, 17 were lethal to rats, inducing congestion and hemorrhage of stomach and intestine and kidney enlargement, and 8 caused lack of weight gain or weight loss. The other 25 isolates of A. alternat and all the isolates of A. sesami, A. sesamicola and A. solani, showed no significant indication of toxicity. Production of mycotoxins in the rice cultures of the above 75 isolates belonging to 4 species was analyzed. Alternaria cultures were extracted with methanol and purified by using solvent partition, thin-layer chromatography, and high performance liquid chromatography. Of the four species tested, all produced alternariol (AOH) and alternariol monomethyl ether (AME), three (A. alternata, A. sesami and A. sesamicola) produced alternuene (ALT) and altertoxin-I (ATX-I), and only A. alternata produced tenuazonic acid (TA). TA was produced by all of the highly toxic (lethal to rats) isolates of A. alternata, but not by any nontoxic isolates.

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Alternaria alternata에 항균력이 있는 천연물 조사 (Screening for Antagonistic Natural Materials Against Alternaria alternata)

  • 김영호;오연현;오승환
    • 한국식물병리학회지
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    • 제12권1호
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    • pp.66-71
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    • 1996
  • 79종의 식물재료의 Alternaria alternata에 대한 항균활성을 조사한 결과, 7가지 식물재료가 항균활성이 있었고, 11가지는 확실치 않았으며, 나머지 61가지는 항균활성이 나타나지 않았다. A. alternata에 항균활성이 나타난 7가지 식물재료 중 계피가 활성이 가장 높았으며, 오미지와 천궁이 중정도의 활성을 보였으며, 나머지는 약한 활성을 나타내었다. 항균 활성 성분은 계피와 천궁의 경우는 diethyl ether에 분리되었고, 오미자의 경우는 butanol에 분리되었다. 계피의 diethyl ether 추출물은 1,000 배액 이하에서 식별 가능한 항균활성이 나타났다. 계피의 성분으로 cinnam aldehyde가 가장 높은 활성을 보여, 이 물질이 계피의 주요 항균물질로 사료된다.

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The Mitogen-Activated Protein Kinase Signal Transduction Pathways in Alternaria Species

  • Xu, Houjuan;Xu, Xiaoxue;Wang, Yu-Jun;Bajpai, Vivek K.;Huang, Lisha;Chen, Yongfang;Baek, Kwang-Hyun
    • The Plant Pathology Journal
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    • 제28권3호
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    • pp.227-238
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    • 2012
  • Mitogen-activated protein kinase (MAPK) cascades are conserved signaling modules in the eukaryotic cells. They are involved in many major cell processes in fungi such as stress responses, vegetative growth, pathogenicity, secondary metabolism and cell wall integrity. In this review, we summarized the advances of research on the MAPK signaling pathways in Alternaria species. As major phytopathogenic fungi, Alternaria species reduce crop production. In contrast to the five MAPK pathways known in yeast, only three MAPK pathways as Fus3/Kss1-type, Hog1-type, and Slt2-type have been characterized in Alternaria. The Fus3/Kss1-type MAPK pathway participates in regulation of vegetative growth, conidiation, production of some cell-wall-degrading enzymes and pathogenicity. The Hog1-type pathway is involved in osmotic and oxidative stress, fungicides susceptibility and pathogenicity. The Slt2-type MAP kinases play an important role on maintaining cell wall integrity, pathogenicity and conidiation. Although recent advances on the MAPK pathways in Alternaria spp. reveal many important features on the pathogenicity, there are many unsolved problems regarding to the unknown MAP kinase cascade components and network among other major signal transduction. Considering the economic loss induced by Alternaria spp., more researches on the MAPK pathways will need to control the Alternaria diseases.

서울 지방의 공중(空中) 진균(眞菌)에 관한 연구(硏究) (Air-borne Fungi in the Air of Seoul)

  • 민경희;이영자
    • 한국균학회지
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    • 제13권2호
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    • pp.115-121
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    • 1985
  • 우리나라 서울 지역의 상업지역, 교통지역, 주택지역, 공장지역, 목욕탕, 백화점, 병원지역 등을 대상으로 open plate method를 사용하여 공중균을 분리한 결과 총 2,227개의 spore를 분리하였다. 그중 Cladosporium이 1,008 spores, Penicillium이 351 spores, Alternaria가 234s, Aspergillus가 84s이며 그리고 미동정된 spore수는 524이었다. 옥내와 옥외의 균의 분포를 비교 고찰한 결과 옥내보다 옥외에서 균의 종류가 더 다양하였다 옥내와 옥외에서 발견된 균중 빈도가 많은 네균류의 분포를 보면, Cladosporium, Penicillium, Alternaria, Aspergillus순으로 많이 나타났다. 그 중 Cladosporium, Penicillium, Aspergillus는 옥내에서, Alternaria고는 옥외에서 더 많이 분리 되였다. 옥외지역의 경우 상업지역, 교통지역, 주택지역 순으로 균이 많이 분포 되었고, 옥내에서는 공장지역, 백화점, 목욕탕, 병원지역의 순서로 많이 나타난다. 계절별로 보면 총 코로니수가 여름, 가을에 걸쳐 많았고, 봄과 겨울이 적은 편이었다. Cladosporium, Penicillium, Aspergillus 경우에는 가을에 많이 분포되어 있었으며, Alternaria는 여름에 많이 분리되었다. 그리고 Cladosporium은 계절별 커다란 차이가 나타나나 Penicillium, Alternaria는 계절별 차이가 적고 Aspergillus는 계절별 차이가 거의 없었다. 상업지역, 교통지역, 주택지역 등의 옥외 지역을 계절별로 조사한 결과 이들 세 지역 모두 여름과 가을에 걸쳐 많은 균의 분포를 나타내었다. 공장지역, 백화점, 병원지역 등의 옥내지역에서도 마찬가지로 여름과 가을에 가장 많은 균이 분리되었으나 계절 변화에 큰 영향을 미치지 못하는 목욕탕만은 계절적 차이가 현저하게 나타나지 많았다.

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