• The Plant Pathology Journal
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• 제31권4호
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• pp.402-413
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• 2015

Yellow rust (stripe rust), caused by Puccinia striiformis f. sp. tritici, is one of the most destructive foliar diseases of wheat in Egypt and worldwide. In order to identify wheat genotypes resistant to yellow rust and develop molecular markers associated with the resistance, fifty F8 recombinant inbred lines (RILs) derived from a cross between resistant and susceptible bread wheat landraces were obtained. Artificial infection of Puccinia striiformis was performed under greenhouse conditions during two growing seasons and relative resistance index (RRI) was calculated. Two Egyptian bread wheat cultivars i.e. Giza-168 (resistant) and Sakha-69 (susceptible) were also evaluated. RRI values of two-year trial showed that 10 RILs responded with RRI value >6 <9 with an average of 7.29, which exceeded the Egyptian bread wheat cultivar Giza-168 (5.58). Thirty three RILs were included among the acceptable range having RRI value >2 <6. However, only 7 RILs showed RRI value <2. Five RILs expressed hypersensitive type of resistance (R) against the pathogen and showed the lowest Average Coefficient of Infection (ACI). Bulked segregant analysis (BSA) with eight simple sequence repeat (SSR), eight sequence-related amplified polymorphism (SRAP) and sixteen random amplified polymorphic DNA (RAPD) markers revealed that three SSR, three SRAP and six RAPD markers were found to be associated with the resistance to yellow rust. However, further molecular analyses would be performed to confirm markers associated with the resistance and suitable for marker-assisted selection. Resistant RILs identified in the study could be efficiently used to improve the resistance to yellow rust in wheat.

• Mycobiology
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• 제44권4호
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• pp.335-337
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• 2016

During the growing season of 2015, leaf specimens with yellow rust spots were collected from Salix koreensis Andersson, known as Korean willow, in riverine areas in Cheonan, Korea. The fungus on S. koreensis was identified as the rust species, Melampsora yezoensis, based on the morphology of urediniospores observed by light and scanning electron microscopy, and the molecular properties of the internal transcribed spacer rDNA region. Pathogenicity tests confirmed that the urediniospores are the causal agent of the rust symptoms on the leaves and young stems of S. koreensis. Here, we report a new rust disease of S. koreensis caused by the rust fungus, M. yezoensis, a previously unrecorded rust pathogen in Korea.

• Mycobiology
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• 제42권1호
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• pp.79-81
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• 2014

From June to October 2012, severe outbreaks of rust disease on Solidago virgaurea var. gigantea were observed in 5 different regions of Ulleung-do, Korea. Typical rust symptoms appeared as yellow spots, uredinia on leaves, and massive urediniospores covering the entire plant. Severely infected plants became discolored and died. On the basis of its morphological and molecular characteristics, the causal agent was identified as Coleosporium asterum. This pathogen has been reported as rust disease on S. virgaurea in the Canada and United States. In Korea, rust disease on S. virgaurea var. gigantea was reported as Uromyces rudbeckia in 1992. To the best of our knowledge, C. asterum is a novel rust pathogen on S. virgaurea var. gigantea in Korea.

• Mycobiology
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• 제43권3호
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• pp.351-353
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• 2015

Farfugium japonicum is used in traditional medicine and as an edible herb in China and Korea. In July 2013, leaf spots were observed in F. japonicum seedlings at Ulleung Island, Gyeongsangbuk Province, Korea. Early symptoms on the leaf adaxial surface included roughly circular yellow spots that later developed brown, necrotic centers. The aecia were hypophyllous, cupulate, yellowish, $180{\sim}430{\mu}m$ in diameter, clustered, and erumpent with a peridium with a recurved margin. The aeciospores were globoid, $14{\sim}17{\times}13{\sim}16{\mu}m$, light yellow or colorless, and densely verrucose. The 28S rDNA sequence of the isolate was identical to each other and shared 99% identity with Puccinia caricis. This is the first report of rust caused by P. caricis in F. japonicum in Korea or elsewhere in the world.

• The Plant Pathology Journal
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• 제23권1호
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• pp.7-12
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• 2007

Perilla rust is a damaging disease in perilla cultivation in Korea. Its causal agent was identified as Coleosporium plectranthi based on descriptions of morphological characteristics of spores and spore-producing fruiting structures(in uredinial and telial stages from perilla and in aecial stage from the alternate host pine) collected in 15 locations in Korea during the disease survey from 2004 to 2006. These characteristics were yellow or orange uredinium; globose or ellipsoid urediniospore of $20.8{\mu}m{\times}18{\mu}m$ in size; verruca of $0.3mm{\times}1.2mm$; orange telium; one-celled, oblong ellipsoid teliospore of $63.1{\mu}m{\times}19.7{\mu}m$ with one-layered crusts or four-celled(when mature), internal basidium of $64.2{\mu}m{\times}19.7{\mu}m$; ellipsoid to globoid basidiospore of $20.3{\mu}m{\times}12{\mu}m$; type 2 spermogonium; yellow, broadly ellipsoid peridial cell of $35.6{\mu}m{\times}23.1{\mu}m$; and broadly ellipsoidal or subglobose aeciospore of $25.9{\mu}m{\times}18.8{\mu}m$. Phylogenetic analysis of 28S rDNA sequences revealed the closest relatedness to those of the genus Coleosporium, a monophyletic group distinguished from other rust fungi and divided into two main lineages, one of which was C. plectranthi grouped with high bootstrap value(96%). In pathogenicity test, both aeciospores and urediniospores caused rust development on perilla leaves. This is the first description of C. plectranthi causing perilla rust with the first findings of its telial stage on perilla and the first rust disease on the aecial host in Pinus densiflora. These aspects would provide basic information for the development of control measures of the disease.

• 식물병연구
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• 제30권1호
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• pp.20-25
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• 2024

A fungus strain Stereostratum corticioides PKVL1, belonging to the family Pucciniaceae that causes rust in plants, was discovered on the sheath of the bamboo Pseudosasa japonica leading to the death of the infected bamboo in the following year. Microscopic observation of the yellow fungal mass revealed teliospores with an oval, one-septate (two-celled) structure. The average length and width of teliospores were 31.83±3.57 ㎛ and 20.74±1.72 ㎛, respectively. The large-subunit ribosomal RNA gene was amplified using the LR0R and LR7 primers, showing that the strain PKVL1 had a similarity of 99.34% to previously reported S. corticioides. In particular, the two Stereostratum strains form a separate cluster among the fungi in the family Pucciniaceae. This is the first report in the Republic of Korea of fungal rust occurring on the culm of bamboo rather than on the leaves.

• 식물병연구
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• 제13권3호
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• pp.220-222
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• 2007

2006년 전라북도 전주에서 산철쭉(Rhododendron yedoense)에 녹병이 심하게 발생하였다. 처음에는 잎 표면에 황색의 작은 반점을 다수 형성하고, 표피가 갈라지면서 약간 부풀어 오르며, 병이 진전됨에 따라 병반에 황색 또는 갈색의 포자퇴가 두드러지게 나타났다. 여름포자퇴는 잎의 앞쪽에 생기고, 잎 표면에 흩어져 있거나 무리를 지어 형성하였으며, 전체적인 모양이 원형 또는 난형이었다. 황색 또는 황갈색을 나타내고, 크기는 $0.27{\sim}0.46{\times}0.31{\sim}0.6$ mm 이었다. 여름포자는 원형 또는 난형이며, 황색으로 크기는 $17.1{\sim}29.2{\times}12.8{\sim}18.2{\mu}m$이었다. 녹포자 표면의 돌기 높이는 $0.87{\sim}1.72{\mu}m$이며, 돌기의 구조는 Type SA, $2{\sim}3$개의 환상고리(annotation)가 있으며, 돌기의 정단부분은 편평하였다. 병징과 병원균의 균학적 특징을 검정한 결과, 이 병을 Chrysomyxa rhododendri에 의한 산철쭉 녹병으로 명명하고자 제안한다.

• 한국균학회지
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• 제32권1호
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• pp.54-56
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• 2004

2003년 경상남도 고성군 회화면 야생화 재배포장에서 범부체 잎에 녹병이 심하게 발생하였다. 처음 잎에 작은 황색 또는 황록색의 작은 반점을 형성하며 병이 진전됨에 따라 표피가 터지면서 병반부에서 밤갈색의 하포자 가루를 많이 형성한다. 심하게 발생된 잎은 시들고 말라죽었다. 범부체 녹병균의 하포자는 원형 또는 난형으로 황색 또는 황갈색을 나타내었고, 크기는 $21{\sim}46{\times}18{\sim}38\;{\mu}m$였다. 동포자는 곤봉형 또는 긴 타원형이었으며 갈색을 띠었고, 크기는 $32{\sim}64{\times}12{\sim}26\;{\mu}m$있다. 병징과 병원균의 균학적 특징 및 병원성을 검정한 결과, 이 병을 Puccinia belamcandae에 의한 범부체 녹병으로 명명하고자 제안한다.

• 식물병연구
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• 제26권3호
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• pp.179-182
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• 2020

2018년 7월 전라남도 강진군의 가로수 전체 이팝나무에 심각한 녹병증상이 발견되어 잎을 채집하였다. 채집한 이팝나무 잎 앞면에서 황색 및 갈색의 병반과 잎 뒷면에서 황색의 녹포자기가 관찰되었고, 현미경아래에서 41.2 ㎛ 크기의 구형 녹포자와 28.84 ㎛ 크기의 구형 하포자가 확인되었다. 이팝나무 녹병균의 부분 small subunit rRNA, internal transcribed spacer (ITS) 1, 5.8S rRNA, ITS2, 부분 large subunit rRNA 염기서열을 이용하여 계통학적 유연관계를 분석한 결과, 대나무 녹병균으로 보고 되어져 있는 Puccinia kusanoi와 가까운 근연관계를 가지고 있었다. 또한 2019년 5월 무위사로 이팝나무 주변에 식재된 대나무에서도 녹병 병징이 관찰되었고, 잎 뒷면에서 동포자퇴와 동포자를 확인하였으며, 대나무에서 채집한 동포자의 염기서열 분석 결과, 이팝나무 녹병균과 100% 일치하였다. 본 논문은 대나무 녹병균으로 알려진 P. kusanoi와 근연관계가 가까운 새로운 종 Puccinia sp. JCK-KCFR1 strain (MT729824)가 국내에서 이팝나무와 대나무를 기주교대하며 녹병을 발생시키는 것을 처음으로 보고한다.

• The Plant Pathology Journal
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• 제33권2호
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• pp.125-132
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• 2017

Tan spot (TS), caused by the fungus Pyrenophora tritici-repentis (Died) Drechs, is an important foliar disease of wheat and has become a threat to world wheat production since the 1970s. In this study a globally diverse pre-1940s collection of 247 wheat genotypes was evaluated against Ptr ToxA, P. tritici-repentis race 1, and stem rust to determine if; (i) acquisition of Ptr ToxA by the P. tritici-repentis from Stagonospora nodorum led to increased pathogen virulence or (ii) incorporation of TS susceptibility during development stem rust resistant cultivars led to an increase in TS epidemics globally. Most genotypes were susceptible to stem rust; however, a range of reactions to TS and Ptr ToxA were observed. Four combinations of diseasetoxin reactions were observed among the genotypes; TS susceptible-Ptr ToxA sensitive, TS susceptible-Ptr ToxA insensitive, TS resistant-Ptr ToxA insensitive, and TS resistant-Ptr ToxA toxin sensitive. A weak correlation (r = 0.14 for bread wheat and -0.082 for durum) was observed between stem rust susceptibility and TS resistance. Even though there were no reported epidemics in the pre-1940s, TS sensitive genotypes were widely grown in that period, suggesting that Ptr ToxA may not be an important factor responsible for enhanced prevalence of TS.