• Mycobiology
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• 제51권4호
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• pp.195-209
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• 2023

The seed borne disease such as bakanae is difficult to control. Crop yield loss caused by bakanae depending on the regions and varieties grown, ranging from 3.0% to 95.4%. Bakanae is an important disease of rice worldwide and the pathogen was identified as Fusarium fujikuroi Nirenberg (teleomorph: Gibberella fujikuroi Sawada). Currently, four Fusaria (F. fujikuroi, F. proliferatum, F. verticillioides and F. andiyazi) belonging to F. fujikuroi species complex are generally known as the pathogens of bakanae. The infection occurs through both seed and soil-borne transmission. When infection occurs during the heading stage, rice seeds become contaminated. Molecular detection of pathogens of bakanae is important because identification based on morphological and biological characters could lead to incorrect species designation and time-consuming. Seed disinfection has been studied for a long time in Korea for the management of the bakanae disease of rice. As seed disinfectants have been studied to control bakanae, resistance studies to chemicals have been also conducted. Presently biological control and resistant varieties are not widely used. The detection of this pathogen is critical for seed certification and for preventing field infections. In South Korea, bakanae is designated as a regulated pathogen. To provide highly qualified rice seeds to farms, Korea Seed & Variety Service (KSVS) has been producing and distributing certified rice seeds for producing healthy rice in fields. Therefore, the objective of the study is to summarize the recent progress in molecular identification, fungicide resistance, and the management strategy of bakanae.

• The Plant Pathology Journal
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• 제24권1호
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• pp.31-35
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• 2008

The presence of Chrysanthemum stunt viroid (CSVd) in seed and pollen of diseased chrysanthemum was demonstrated. In seeds infected male parent from crosses in May, CSVd was transmitted to 6.7% of the progeny seedlings, whereas if the female parent was infected, CSVd transmission rate was between 46.9 and 75.7%. A relatively high incidence of 94.4 to 96.0% seed transmission occurred when both parents were infected. In seeds infected male parent from crosses in December, no progeny seedlings were infected with CSVd, whereas if the female parent did, CSVd transmission rate was 1.5%. When both parents were infected, 6.9% seed transmission was occurred. The seed transmission rate depended on the temperature when the crosses were made. CSVd was not detected in the non-infected female parent pollinated with infected pollen but was transmitted to the progenies. This is the first report of seed-borne transmission of CSVd in chrysanthemum.

• 식물병연구
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• 제16권2호
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• pp.121-124
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• 2010

박과작물에 발생하는 종자전염 바이러스 3종(CGMMV, KGMMV, ZGMMV)에 대한 검출을 위해 IC-RT-PCR의 적용 가능성을 시험하였다. IC-RT-PCR을 이용하여 감염 종자와 잎으로 부터 바이러스의 특이적인 검출이 가능하였으며, 검출 민감도는 ELISA 보다 100배 이상 높았다. 또한 반응을 마친 ELISA 마이크로플레이트에 남아있는 항원을 IC-RT-PCR의 template로 사용할 경우 ELISA 결과를 곧바로 확인할 수 있었다. 따라서 IC-RT-PCR에 의한 본 검정방법은 박과작물의 대규모 포장검사 및 종자검사에 편리하게 사용될 수 있을 것으로 기대된다.

• 한국균학회지
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• 제15권3호
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• pp.183-186
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• 1987

토양전염성균(土壞傳染性菌)으로 알려진 Colletotrichum coccodes가 고추 종자(種子)에서 처음으로 검출(檢出)되었다. 이 균(菌)의 종자상(種子上)에서의 생육상(生育相)과 분생포자(分生胞子)의 형태적(形態的) 특징(特徵)을 기술(記術)하였다. 병원성(病原性) 실험(實驗)의 결과(結果) 이 균(菌)은 고추 뿐 아니라 토마토, 가지의 열매에 탄저병(炭疽病)을 일으켰다.

• 식물병연구
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• 제17권2호
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• pp.148-154
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• 2011

본 연구는 당근의 유기재배를 위하여 13개의 친환경 제제를 이용한 당근의 Alternaria spp.에 의한 종자전염성 병원균 방제 및 종자 발아율 조사를 수행하였다. 병원균의 생장억제 효과는 친환경 제제 별로 차이를 보였으며 효과가 좋은 7개 제제를 선발하였다. 7개 친환경제제별종자소독 후 발아율 조사에서는 식물 추출물인 탄저스탑과 랜드세이버 제제로 소독된 종자는 발아가 전혀 되지 않았으며 다른 친환경제제에서 소독된 종자의 발아율은 대조약제(Benlate-T)와 무처리 종자의 발아율과 비슷하였다. 탄저스탑과 랜드세이버를 제외시킨 감염율 조사에서는 A. radicina 균에 대한 해조류 추출물인 벨로퍼, A. dauci 균은 식물 추출물인 씨알-100으로 소독된 종자가 감염율이 10% 미만으로 대조약제와 비슷하거나 낮게 나타났다. 이들 제제는 뿌리길이 및 유묘검정 발아율 조사도 대조약제로 소독한 종자와 비슷하거나 우수한 것으로 조사 되었다. 본 시험의 결과로 보아 종자소독의 최적의 조건은 약제별 농도에 따라 다소 다르며 친환경 제제를 이용한 종자소독은 종자전염성 병원균을 효과적으로 억제할 수 있는 기술로 활용될 수 있다.

• 한국식물병리학회지
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• 제13권1호
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• pp.18-21
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• 1997

Bipolaris panici-miliacei, Cercospora fusimaculans, Fusarium moniliforme and Rhizoctonia solani were pathogenic fungi detected from 5 seed samples of common millet (Panicum miliaceum). Morphological characters of B. panici-miliacei were as follows. Conidiophores were dark olivaceous brown, simple, cylindrical, geniculate, and septate. Conidia were fusoid, dark olivaceous brown, tapering gradually toward the ends, straight to slightly curved, 3~13 distoseptate, and 29.4~155.4$\times$10~26 ${\mu}{\textrm}{m}$ in size with dark hilum included within the contour of the basal cell. Seed infection with B. panici-miliacei caused seed rotting, coleoptile spot, and seedling blight of common millet plants. According to the inoculation experiments, B. panici-miliacei showed strong virulence on the young seedlings of common millet, but very weak virulence on the young seedlings of rice (Oryza sativa) and foxtail millet (Setaria italica).

• Mycobiology
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• 제51권6호
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• pp.463-467
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• 2023

Soybean is one of the world's most widely cultivated food crops, and soybean seeds are supplied from national seed resources in Korea. However, the transmission of seed-borne diseases through infected soybean seeds is problematic. Among these diseases, soybean seed decay is caused by Diaporthe spp. Infecting the pods, and the infected seeds show rotting symptoms. Most diseased seeds are removed during the selection process; however, it is difficult to distinguish infected seeds that do not display symptoms. Hence, a sequencebased method was devised to screen Diaporthe-infected seeds. Based on the nuclear ribosomal internal transcribe spacer (ITS) region of the pathogen, a primer was designed to distinguish the infection from other soybean seed pathogens. As a result of the comparison between healthy and Diaporthe-diseased seeds by using the primers, Diaporthe was detected only in the diseased seeds. Therefore, it is possible to distribute healthy soybean seeds by detecting Diaporthe-diseased seeds at the genetic level using the Diaporthe-specific primers.

• Mycobiology
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• 제29권2호
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• pp.104-106
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• 2001

Alternaria cassiae Jurair & Khan was recorded on seeds of sickle senna(Cassia tora L.). Seed infection ranged from $25{\sim}45%$ in two samples. Developing roots and shoots turn brown and died in case of severe infection. Detailed descriptions were given on the habit characters of the fungus and on the morphology of conidiophores and condia. This is the first report of A. cassiae on seeds of Cassia.

• 농업과학연구
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• 제6권1호
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• pp.27-32
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• 1979

충남농촌진흥원으로부터 분양받은 참깨종자의 종자전염진균을 표준 Blotter 법으로 조사하였던 바 12종의 균류가 검출되었다. 그 중 Alternaria sesamicola, A. tenuis, Corynespora cassicola가 많은 비율로 검출되었다. Chlorine으로 종자처리를 하였을 경우, C. cassicola를 제외한 모든 균이 거의 완전히 제거되었다. 참깨 종자내의 감염부위는 C. cassicola가 가장 깊숙이 배에까지 감염되어 있었다. C. cassicola의 병원성을 조사하였던 결과 참깨의 잎과 줄기에 심한 반점을 형성하고 병반이 급격히 확대되며 말라죽었다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.119.2-120
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• 2003

Seed-borne fungal pathogens on rice seeds were investigated in order to evaluate their effect on rice grain quality. Rice seeds of two cultivars, Ilmibyeo and Daesanbyeo were collected from 27 areas of Korea and the fungal parasites on seeds were isolated by using a blotter method. Isolation frequency and number of species were varied from collection areas of seed samples. A total 13 species of fungi were identified from the seeds. Among them, Altemana alternata was the most frequent over the country. Bipoiaris oryzae most commonly from Gyeongbuk and Jeonbuk, Alternaria padwickii from Jeonbuk, and Nigrospora oryzae from Choongnam. However Bipolaris. oryzae, Alternaria padwickii, and Nigrospora oryzae were the most frequently isolated fungi from Gyeongbuk and Jeonbuk, and Chungnam, respectively. B. oryzae, A. alternata, A. padwickii, and N. oryzae were dominants on Ilmibyeo showing 10.3％, 10.2％, 5.2％, and 5.2％ infection rate, respectively. While, N. oryzae, A alternata, and Cladosporium sp. were most frequently isolated fungi from Deasanbyeo revealing 15.1％, 9.6％, and 7.5％ infection rate, respectively. These fungi inhabiting on hulls or endosperms of rice seed might be considered as potential factors decreasing rice grain quality. Further investigation of the fungi on grain rice quality are undergoing.