• The Plant Pathology Journal
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• 제25권3호
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• pp.294-298
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• 2009

Stem canker symptoms were observed in a rape field in Muan, Korea during a disease survey in May 2006. A total of 15 isolates of Phoma sp. were obtained from the infected stems of the plant. All isolates were identified as Leptosphaeria biglobosa based on their morphological and cultural characteristics. The Korean isolates of L. biglobosa were assigned to 'brassicae' among six subclades of L. biglobosa complex based on the entire ITS sequences of rDNA. Pathogenicity of the fungal isolates was confirmed on leaves and stems of rape by artificial inoculation. This is the first report that Leptosphaeria biglobosa causes stem canker of rape in Korea.

• 식물병연구
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• 제28권3호
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• pp.132-142
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• 2022

Plantation forests are established by planting Eucalyptus tree species to provide timber and pulp for the construction industries and to meet the energy needs in Ethiopia. Besides the extensive Eucalyptus plantations in the country, fungal pathogen-related diseases are the main challenges to successful production and management. The disease survey was conducted in the Eucalyptus growing areas of Ethiopia during 2019/2020 and 2020/2021. The objective of this research was to assess the diseases associated with Eucalyptus plant species and identify the causal fungal species. Plants of E. camaldulensis were the dominant species in the survey fields and were severely associated with stem and branch canker diseases. Diseased samples were collected and fungal species were identified as Didymellaceae according to culture morphology and affirmed by internal transcribed spacer sequence analysis. In phylogeny, isolates in the study and a reference strain formed supportive monophyletic clades with strong 90% and 95% support with Didymella coffeae-arabicae and Didymella pinodella respectively. Pathogenicity tests revealed that Didymellaceae could infect E. camaldulensis. The findings are the first reports of Eucalyptus stem canker disease caused by Didymellaceae in Ethiopia.

• The Plant Pathology Journal
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• 제28권1호
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• pp.55-59
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• 2012

Northern stem canker caused by $Diaporthe$ $phaseolorum$ var. $caulivora$ ($Dpc$) has become a serious disease in soybean. The objectives of this study were to survey the existence of $Dpc$ on soybean in Korea, and to examine the potential pathogenicity of $Dpc$ in seed decay. One such isolate, SSLP-4, isolated from a field-grown plant of the Korean soybean cultivar Danbaekkong, was identified as $Dpc$, based on its morphological and molecular characteristics by sequences of internal transcribed spacer (ITS), translation elongation factor (TEF) 1-${\alpha}$ and ${\beta}$-tubulin regions, as well as pathogenic analyses. Moreover, morphological and molecular analyses revealed that isolate SSLP-4 was nearly identical to $Dpc$ strains from the United States. Pathogenicity tests on hypocotyls of soybean seedlings and detached leaves resulted in typical symptoms of soybean northern stem canker and inoculation on plants at R5-R7 stage caused seed decay. All results suggest that the $Dpc$ strain SSLP-4 can cause both stem canker and seed decay on soybean. Thus, the SSLP-4 isolate has the potential to contribute greatly to understanding of host plant resistance mechanisms, both at vegetative and reproductive growth stages in soybean.

• 한국균학회지
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• 제40권4호
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• pp.266-270
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• 2012

2011년 안동과 진주의 마 재배포장에서 줄기 지제부 및 괴근썩음 증상이 나타났다. 병징을 나타내는 부위로부터 Rhizoctonia와 유사 속에 속하는 20개 균주가 분리되었다. rDNA-internal transcribed spacer(ITS) 염기서열 상동성을 기초로 8균주는 Rhizoctonia solani, 12균주는 Ceratobasidium sp.로 동정되었다. rDNA-ITS 염기서열의 cluster 분석에 의해 R. solani에 속하는 8개 균주 중 7개 균주는 균사융합군 AG 2-2IIIB, 1균주는 AG 1-1A에 속하였다. 또한, Ceratobasidium sp.에 속하는 12균주 중 7균주는 AG-Fa, 3균주는 AG-A, 나머지 2균주는 각각 AG-Fb와 AG-O에 속하였다. R. solani AG 2-2IIIB 균주들은 마의 줄기와 괴근에 병원성이었으나 R. solani AG 1-1A와 모든 Ceratobasidium sp. 균주는 비병원성이라는 것이 확인되었다. 이 결과는 조사지역에서 R. solani AG 2-2IIIB가 마의 줄기 및 괴근썩음병을 일으키는 중요한 병원균이라는 것을 나타낸다. 이 연구는 국내에서 R. solani AG 2-2IIIB에 의한 마 뿌리썩음병에 대하여 처음으로 보고하는 것이다.

• Mycobiology
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• 제43권3호
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• pp.366-370
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• 2015

Acanthopanax divaricatus, a member of the Araliaceae family, has been used as an invigorant in traditional Korean medicine. During disease monitoring, a stem with small, irregular, brown lesions was sampled at a farm in Cheonan in 2011. The symptoms seen were sunken cankers and reddish-brown needles on the infected twig. The isolated fungal colonies were whitish, having crenated edges and aerial mycelium on the surface, and with black gregarious fruiting bodies. The reverse plate was creamy white. Conidia were $17{\sim}22{\times}3.5{\sim}4.2{\mu}m$, fusiform, 4-septate, and straight to slightly curved. The nucleotide sequence of the partial translation elongation factor 1 alpha gene of the fungal isolate, shares 99% sequence identity with that of known Pestalotiopsis ellipsospora. Based on the results of the morphological and molecular analyses, the fungal isolate was identified as P. ellipsospora. In Korea, this is the first report of canker on A. divaricatus.

• 식물병연구
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• 제22권4호
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• pp.217-226
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• 2016

궤양병에 의해 자연감염된 전남 보성군 조성면 헤이워드 과수원에서 2014년과 2015년 궤양병 발생소장을 주기적으로 조사했다. 줄기궤양병은 2014년에 2월 중순부터 2015년에는 3월 초순부터 발생하기 시작하였는데, 줄기에서 세균 유출액이 흘러내리기 시작하여 4월 하순 무렵까지 지속되다가 5월에 접어들면 더 이상 세균유출액을 관찰할 수 없고 줄기 표면에 궤양병 병반만 나타났다. 2014년 줄기궤양병 감염률이 44.7%였지만 2015년에는 69.7%로 급증하였는데, 주간부까지 감염된 나무들은 1년 후 대부분 고사했다. 잎궤양병은 5월 초순부터 잎에 연두색 둥근 달무리 증상이 나타나고 점차 노란 테두리를 가진 갈색 점무늬 병징이 변하면서 확산되기 시작하였으며 습한 조건에서는 노란 테두리가 없는 갈색 점무늬들이 관찰되었다. 2014년에는 7월 중순까지 2015년에는 7월 하순까지만 잎에 새로운 병반들이 형성되었으며 이미 형성된 병반에서도 Psa는 검출되지 않았다. 기온이 다시 내려간 2014년 10월 하순 무렵에 잎에서 다시 새로운 병반이 잎에 드물게 나타났다. 꽃봉오리에는 개화전 5월 중순 무렵에 꽃받침이 괴사되는 꽃봉오리들이 관찰되었다. 키위 궤양병의 모니터링 적기는 줄기와 잎, 꽃봉오리 모두에서 궤양병 병징이 나타나고 Psa가 잘 분리되는 5월로 확인되었다. 전남 보성에서 2년 동안 기상자료에 따른 궤양병의 발생소장 분석결과를 토대로 우리나라에 적합한 키위 궤양병의 병환을 작성했다.

• KSBB Journal
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• 제10권2호
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• pp.166-169
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• 1995

감 자 Rhizoctoηia stem canker 방 제 용 의 Trichoderma harzianum A Tee 52445 의 포자를 각종 천연담체에 고정화시킨 후 발아율과 강도 벚 점착성 등의 물성을 조사하였다. 천연담체 중 gelatin과 감자 전분 젤에 포자를 고정화시켰을 때 각각 2.81 % 와 2.90%의 발아율을 보였고 강도와 점착성은 감자 전분 고정화 겔보다 gelatin 고정화 겔이 우수하였 다 .. Gelatin에 몇 종의 물성 이 우수한 담체를 섞 어 서 만든 혼합담체에 포자를 고정화시 켰을 경우 물성 은 개선이 되었으냐 발아율은 오히려 낮아졌고 1% 의 corn steep liquor를 gelatin에 첨가하여 포자를 고정화시켰을 때 말아율이 약 0.6% 상승되었다.

• Journal of Forest and Environmental Science
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• 제38권2호
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• pp.137-139
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• 2022

In 2021, severely infected trees showing distinct symptoms including branch dieback, necrotic lesions on branches, cankers on the shoots, and dark brown discoloration on the stem on Hovenia dulcis were found in the provincial forest of Jeollabuk-do located in Jangsu, South Korea. The causal agent of the pathogen was identified as Botryosphaeria dothidea based on morphology and sequence comparisons. This is the first confirmed report of B. dothidea causing branch dieback and canker on H. dulcis.

• The Plant Pathology Journal
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• 제32권2호
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• pp.85-94
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• 2016

Studies were conducted to determine the role of 3-methylthioproprionic acid (MTPA) in the pathogenicity of potato stem canker, Rhizoctonia solani, and the concentrations required to inhibit growth of R. solani under laboratory and plant house-based conditions. The experiments were laid out in a completely randomized design with five treatments and five replications. The treatments were 0, 1, 2, 4, and 8 mM concentrations of MTPA. The purified toxin exhibited maximal activity at pH 2.5 and $30^{\circ}C$. MTPA at 1, 2, 4, and 8 mM levels reduced plant height, chlorophyll content, haulm fresh weight, number of stolons, canopy development, and tuber weight of potato plants, as compared to the control. MTPA significantly affected mycelial growth with 8 mM causing the highest infection. The potato seedlings treated with MTPA concentrations of 1.0-8.0 mM induced necrosis of up to 80% of root system area. Cankers were resulted from the injection of potato seedling stems with 8.0 mM MTPA. The results showed the disappearance of cell membrane, rough mitochondrial and cell walls, change of the shape of chloroplasts, and swollen endoplasmic reticulum. Seventy-six (76) hours after toxin treatment, cell contents were completely broken, cytoplasm dissolved, and more chromatin were seen in the nucleus. The results suggested that high levels of the toxin concentration caused cell membrane and cytoplasm fracture. The integrity of cellular structure was destroyed by the phytotoxin. The concentrations of the phytotoxin were significantly correlated with pathogenicity and caused damage to the cell membrane of potato stem base tissue.

• 식물병연구
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• 제12권2호
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• pp.65-68
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• 2006

장미는 세계적으로 가장 많이 재배되고 있는 화훼작물로서 최근에 양액재배 및 토양재배 되는 장미에서 발생하는 줄기마름증상에 대한 연구를 수행하였다. 장미의 가지나 줄기가 말라죽는 증상은 크게 4 가지 병에 의한 것으로 조사되었는데, Botrytis cinerea에 의한 잿빛곰팡이병, Coniothyrium fuckelii에 의한 가지 마름병, Colletotrichum gloeosporioides에 의한 탄저병, 그리고 Pythium sp. 에 의한 뿌리썩음병이었다. 이들 병의 진단과 방제에 도움이 되고자 병 증상과 병원균의 특성에 대하여 기술하였다.