• 한국균학회지
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• 제50권4호
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• pp.255-262
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• 2022

In this study, the fungal strain KNUF-21-F39 was isolated from a declined apple tree (Malus domestica) in the Chungcheongbuk province in Korea. The strain KNUF-21-F39 presented a slow growth rate and a variety of macroconidia shapes and sizes ranging from ovoid to fusoid and 1- to 5-septate, primarily showing 3- and 4-septate, with "S" -shaped macroconidia rarely observed. The strain was identified based on morphological characteristics along with phylogenetic analysis performed using the internal transcribed spacer region (ITS) and partial sequences of translation elongation factor 1-α (tef1), RNA polymerase largest subunit (rpb1), and calmodulin (cal) genes. The fungal strain KNUF-21-F39 was identified as Fusarium diversisporum, which has not been previously reported in Korea. The ice nucleation activity (INA) of the strain was also evaluated, identifying the strain as positive for INA. This is the first report characterizing F. diversisporum as an IN-active fungal species.

• The Plant Pathology Journal
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• 제26권4호
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• pp.394-401
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• 2010

Resin flow, symptom development, and lignin biosynthesis in response to wounding and fungal inoculation were investigated in Pinus rigida and Pinus densiflora. The two-year-old seedling stems were subjected to three types of treatments: (i) wounding without inoculation, (ii) wound-inoculation with a conidial suspension of Fusarium circinatum, and (iii) pre-wounding woundinoculation with the fungus 20 days after the initial wounding. Resin flow from wounding sites was more evident in P. rigida than P. densiflora in all treatments. The wound-inoculation with the fungus induced almost two-fold higher levels of resin flow than the other treatments in both species. The pre-wounding woundinoculation appeared to result in a decrease in pitch canker development in the two pine species. Some reductions in disease severity were observed in the prewounding wound-inoculated P. rigida, showing a mean disease severity of less than 85%, compared with approximately 100% in the wound-inoculated stems. Disease severity was approximately 50% in the woundinoculated P. densiflora, whereas 10% in the pre-wounding wound-inoculated stems. Higher amounts of lignin were found from bark (ca. 40%) than from xylem (ca. 30%). The wound-inoculated bark and the pre-wounding wound-inoculated bark exhibited higher amounts of lignin among the other treatments. These results suggest that the wound-inoculation apparently prompt the increase in resin flow and lignin biosynthesis from the two pine species, and the prior wounding may be involved in decreased disease severity against the further invasion of F. circinatum.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.83.1-83
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• 2003

Rice seedling disease is one of major problems in water-seeded rice. This disease is known to be caused by several pathogen such as Pythium, Achlya, and Fusarium species. However, seedling disease of rice in water-seeded rice in Korea is not extensively studied. Pythium species have been isolated from Seosan, Yeoju, Icheon areas using Pythium selective media and their pathogenicity was investigated. All of the Pythium isolates showed strong pathogencity causing seedling emergence reduction in water-seeded rice. Seedling emergence was reduced to 0∼9％ at 10 days after inoculation of 23 Pythium isolates compared to 60％ of noninoculated control in a growth chamber. However, Fusarium species did not cause seedling emergence reduction in water-seeded rice. In contrast, when no water added into water agar or soil, the pathogen caused seedling rot two weeks after planting. These results indicate that Pythium species is a cause of seedling disease in water-seeded cultivation areas in Korea.

• 식물병연구
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• 제7권2호
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• pp.93-101
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• 2001

1996년부터 1998년까지 한국내 십자화과 채소작물의 포장에서 시들음병 발생을 조사한 결과, 배추와 무에서는 발생율이 최대 40%까지 심하게 발생하였으며, 양배추에서는 일부 포장에서만 약간 발생하였다. 시들음증상을 보이는 십자화과 채소작물의 병든 뿌리로부터 총 123균주의 Fusarium균이 분리하였으며, 공시균주들의 형태적 및 배양적 특성을 조사한 결과, 모두 Fusarium of oxysporum으로 동정되었다 공시균주들의 배추 및 양배추에 대한 병원성은 공시품종에 따라 다소 차이는 있었으나 균주들간에 뚜렷하게 구분되지 않았다. 무에 대한 병원성에 있어서는 대체로 무분리 균주들이 배추 및 양배추분리 균주들보다 강한 것으로 나타났다 공시균주들의 십자화과 이외의 채소작물에 대한 병원성검정 결과, 고추 등 8개 작물에 대해 모두 병원성이 없었다 이 연구결과, 배추감염 균주들의 병원형은 양배추감염 균주들의 병원형과 동일하고, 무감염 균주들의 병원형과는 다른 것으로 나타났다.

• The Plant Pathology Journal
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• 제35권2호
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• pp.112-124
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• 2019

Barley worldwide is affected seriously by Fusarium seedling blight (FSB) and Fusarium head blight (FHB) diseases caused by the Fusarium species. The objective of this study was to facilitate the resistance of hulled and hull-less barley at different growth stages to F. culmorum according to direct parameters: disease rating (DR), fresh weight of leaves and roots, kernel weight per spike, kernel number per spike, plump kernels, and indirect parameters - chlorophyll a fluorescence (CF). Plate assay, greenhouse and field tests were performed on 30 spring barley doubled haploid (DH) lines and their parents infected with Fusarium culmorum. Direct parameters proved that hulled genotypes show less symptoms. Most studied chlorophyll a fluorescence (CF) parameters (apart from DIo/CS - amount of energy dissipated from PSII for laboratory test, TRo/CS - amount of excitation energy trapped in PSII reaction centers, ETo/CS - amount of energy used for electron transport and RC/CS - number of active reaction centres in the state of fully reduced PSII reaction center in field experiment) were significantly affected by F. culmorum infection. In all experiments, hulled genotypes had higher values of CF parameters compared to hull-less ones. Significant correlations were detected between direct and indirect parameters and also between various environments. It was revealed that ABS/CS, TRo/CS, and RC/CS have significant positive correlation in greenhouse test and field experiment. Significant correlations suggest the possibility of applying the CF parameters in selection of barley DH lines resistant to F. culmorum infection.

• 한국응용곤충학회지
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• 제7권
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• pp.69-75
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• 1969

본 시험은 오이류 덩굴쪼김병균의 병원성을 조사하기 위하여 실시하였으며 공시균 24균주를 오이, 참외, 김치 참외, 멜론, 수박 및 수세미오이에 접종한 결과는 다음과 같다. 1. 수박분리균은 수박가 멜론에 대하여 강한 병원성을 나타냈고 그 중에는 김치참외 흑은 참외에 대해서도 병원성을 나타낸 것이 있었다. 2. 오이분리균은 병원성에 따라 네가지 형으로 나눌 수 있는데 오이에 대해서 강하게 병원성을 나타내면서 참외, 김치참외 및 멜론을 감염하는 것이 있었으며, 오이에 대해서는 병원성이 없거나 아주 약하게 나타난 것이 김치참외에 대해서는 강한 병원성을 나타낸 것이 있었다. 또 참외, 김치참외 및 멜론에 대해서만 강한 병원성을 나타내고 오이에 대해서는 전혀 병원성이 없는것과 오이, 참외, 김치참외, 멜론에 대해서는 강한 병원성을 나타내는 한편 수박에 대해서도 중간정도의 병원성을 나타내는 것이 있었다. 3. 참외 분리균은 병원성에 따라 네 가지 형으로 나눌 수 있는데 참외, 김치참외 및 멜론을 강하게 침해하는 것과 참외, 김치참외, 멜론은 물론 수박에 대해서도 병원성이 있는 것이 있었다. 또 김치참외 및 멜론에 대해서 병원성이 약하게 나타난 것과 멜론에 대해서는 강하게 병원성을 나타내고 수박을 약하게 침해하는 것이 있었다. 4. 오이류 덩굴쪼 병균은 병원성에 따라 수박덩굴 쪼김병균, 오이덩굴쪼김병균 및 멜론덩굴쪼김 병균으로 대별할 수 있었으나 공시돈 오이류 덩굴쪼김병균간의 병원성이나 기생범위가 반드시 일정하기 않기 때문에 몇 개의 form specine로 재정리하고 오이류에서 선발된 몇가지 판별품종에 대한 병원성에 따라 race로 나누어야 할 것이다.

• Mycobiology
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• 제28권4호
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• pp.197-201
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• 2000

The distribution and occurrence of aquatic zoosporic and terrestrial fungi were investigated in 21 well waters in Assiut governorate, Egypt. Using a zoospore capture technique, 923 colonies of aquatic freshwater fungi were recovered from well waters, out of which 811 colonies reached sexual maturity. These colonies were assigned to 23 species which belong to 11 genera. The most common genera were Achlya, Saprolegnia and Dictyuchus. Using two types of media, 35 species in addition to 2 varieties of terrestrial fungi which belong to 18 genera were also recovered. The most frequent glucophilic genera (recovered on glucose-Czapek's agar at $28^{\circ}C$) were Aspergillus, Penicillium and Fusarium. The results obtained on cellulose-Czapek's agar at $2^{\circ}C$ were basically similar to those on glucose agar and the most frequent genera were Aspergillus, Penicillium and Fusarium followed by Chaetomium and Cephalosporium.

• 아시안잔디학회지
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• 제24권2호
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• pp.165-169
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• 2010

Fusarium circinatum은 소나무류에 푸사리움 가지마름병을 유발하는 병원균으로 알려져 있다. 본 연구에서는 골프장의 리기다소나무로부터 병원균을 분리하였으며, 이들의 형태적인 특성을 관찰하고 분자생물학적인 방법을 이용하여 동정한 결과 F. circinatum 임을 확인하였다. 특히 histone H3 유전자와 IGS rDNA의 염기서열을 분석한 결과 분리된 균들의 염기서열은 동일하였으며, 유성생식(mating)에 관여하는 유전자를 분석한 결과 모두 MAT1-1 유형임을 확인하였다. 또한 푸사리움 가지마름병에 대한 감수성 수종인 리기다소나무를 비롯하여 저항성 수종인 잣나무와 소나무의 메탄올 추출물을 만들어 이들의 병원균에 대한 항균력을 검정하였다. 그 결과 저항성 수종인 잣나무와 소나무의 추출물에서 리기다소나무 보다 높은 항균력을 확인 하였다.

• The Plant Pathology Journal
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• 제34권5호
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• pp.347-355
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• 2018

Fusarium head blight (FHB) caused by Fusarium species is a major disease of wheat and barley around the world. FHB causes yield reductions and contamination of grains with trichothecene mycotoxins including; nivalenol (NIV), deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), and 15-acetyldeoxynivalenol (15-ADON). The objectives of this study were to identify strains of F. graminearum isolated in Korea from 2012-harvested wheat grain and to test the pathogenicity of these NIV- and DON-producing isolates. Three hundred and four samples of wheat grain, harvested in 2012 in Chungnam, Chungbuk, Gyeongnam, Jeonbuk, Jeonnam, and Gangwon provinces were collected. We recovered 44 isolates from the 304 samples, based on the PCR amplification of internal transcribed spacer (ITS) rRNA region and sequencing. Our findings indicate that F. asiaticum was the predominant (95% of all isolates) species in Korea. We recovered both F. asiaticum and F. graminearum from samples collected in Chungnam province. Of the 44 isolates recovered, 36 isolates had a NIV genotype while 8 isolates belonged to the DON genotype (3-ADON and 15-ADON). In order to characterize the pathogenicity of the strains collected, disease severity was assessed visually on various greenhouse-grown wheat cultivars inoculated using both NIV- and DON-producing isolates. Our results suggest that Korean F. graminearum isolates from wheat belong to F. asiaticum producing NIV, and both F. graminearum and F. asiaticum are not significantly different on virulence in wheat cultivars.

• 한국환경과학회지
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• 제28권3호
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• pp.385-392
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• 2019

This study investigated the relationship among seven species of trichoderma through the identification of strains collected in Korea. The phylogenetic tree among the collected strains was classified into four groups. The trichoderma strains isolated in this way showed inhibitory effect on the fusarium wilt which is parasitic to cotyledon stem..The invisibility of J9, J10, J13 and J16 strains were higher in comparison with other strains in vitro test stand, and their spore production level was also higher. In the aluminum ring tests, it showed that the yield of the spores in J9, J10 and J13 were more than any other strain. As a result conducting the port test for cucumbers, the plant lengths of J13 were larger than the control plot, and the root lengths of all strains, except for J2 were longer than the control plot, and the root weights of J1, J9, J10, J13 and J16 were larger than the control plot. The disease severity for the fusarium wilt showed the smallest values at J13 and J16 in comparison with the control plot, and the control values of J13 and J16 were higher than other strains.