• 한국균학회지
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• 제13권1호
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• pp.23-26
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• 1985

묘대별발생(苗代別發生)을 보면 강한(江漢)찰벼와 낙동(洛東)벼에시 상자육묘(箱子育苗)가 보온절충묘대(保溫折衷苗代)보다 종자소독유무(種子消毒有無)에 관계(關係)없이 키다리 병(病)의 발생(發生)이 많았다. 상자육묘(箱子育苗)와 보온절충묘대(保溫折衷苗代)에서 자란 유묘(幼苗)를 일본(一本)씩 이앙(移秧)할 경우 본답(本畓)에서 상자육묘(箱子育苗)에서 자란 유묘(幼苗)가 보온절충묘대(保溫折衷苗代)에서 자란 유묘(幼苗)보다 이병률(罹病率)이 높았고 수량(收量)도 떨어졌다.

• Molecules and Cells
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• 제26권3호
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• pp.258-264
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• 2008

A rice diacylglycerol kinase (DGK) gene, OsBIDK1, which encodes a 499-amino acid protein, was cloned and characterized. OsBIDK1 contains a conserved DGK domain, consisting of a diacylglycerol kinase catalytic subdomain and a diacylglycerol kinase accessory subdomain. Expression of OsBIDK1 in rice seedlings was induced by treatment with benzothiadiazole (BTH), a chemical activator of the plant defense response, and by infection with Magnaporthe grisea, causal agent of blast disease. In BTH-treated rice seedlings, expression of OsBIDK1 was induced earlier and at a higher level than in water-treated control seedlings after inoculation with M. grisea. Transgenic tobacco plants that constitutively express the OsBIDK1 gene were generated and disease resistance assays showed that overexpression of OsBIDK1 in transgenic tobacco plants resulted in enhanced resistance against infection by tobacco mosaic virus and Phytophthora parasitica var. nicotianae. These results suggest that OsBIDK1 may play a role in disease resistance responses.

• The Plant Pathology Journal
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• 제31권4호
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• pp.334-342
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• 2015

Two fumonisin-nonproducing strains of Fusarium verticillioides and their fumonisin producing progenitors were tested for aggressiveness toward maize, sorghum, rice, and beetroot seedlings grown under greenhouse conditions. None of the plants showed obvious disease symptoms after root dip inoculation. Fungal biomass was determined by species-specific real-time PCR. No significant (P = 0.05) differences in systemic colonization were detected between the wild type strains and mutants not producing fumonisins. F. verticillioides was not detected in any of the non-inoculated control plants. The fungus grew from roots to the first two internodes/leaves of maize, rice and beet regardless of fumonisin production. The systemic growth of F. verticillioides in sorghum was limited. The results showed that fumonisin production was not required for the infection of roots of maize, rice and beet by F. verticillioides.

• 한국산림과학회지
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• 제95권6호
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• pp.636-642
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• 2006

야외에서 새로운 송이균환을 만들기 위하여 2000년부터 2005년까지 소나무를 이용한 송이 감염묘 생산과 이식 및 이식 후 송이 균의 활착을 높일 수 있는 방법을 연구하였다. 송이 간염묘 생산을 위해서는 11월에 균환 선단에 심을 경우 활착률 97%를 나타낸 반면 4월에 심을 경우에는 활착률이 80%를 나타냈다. 송이균의 감염은 식재 후 2년 이상 경과하여야 완전히 이루어지는 것으로 나타났으며, 천연치수를 이용한 경우는 17.6%의 송이균 생존률을 나타낸 반면, 양묘를 이용한 경우는 송이균의 생존율이 극히 낮았다. 한편, 생산된 감염묘의 이식 시 송이균의 생존율은 4월에 이식할 경우 22%, 10월과 11월에 이식할 경우에는 5%를 나타냈다. 이식한 송이 감염묘에서 송이균의 생존은 이식전 50% 내외의 송이균 감염율을 가진 감염묘가 가장 높은 생존율을 니타냈다. 이식한 송이 감염묘에서 송이균의 생존 여부 확인을 위하여 송이 감염묘를 완전히 파내어 확인하는 방법은 살아있던 송이균도 이후에 사멸하게 되는 원인이 되었다. 이에 따라 이식한 감염묘의 송이균 확인은 색대를 이용하는 방법을 도입하였으며, 이식 후 2년 이상 경과한 후에 검정하는 것이 송이균의 생존에 유리할 것으로 판단되었다.

• The Plant Pathology Journal
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• 제34권5호
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• pp.393-402
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• 2018

Rice world production is affected due to the growing impact of diseases such as bacterial panicle blight, produced by Burkholderia glumae. The pathogen-induced symptoms include seedling rot, grain rot and leafsheath browning in rice plants. It is currently recognized the entrance of this pathogen to the plant, from infected seeds and from environmental sources of the microorganism. However, it is still not fully elucidated the dynamics and permanence of the pathogen in the plant, from its entry until the development of disease symptoms in seedlings or panicles. In this work it was evaluated the infection of B. glumae rice plants, starting from inoculated seeds and substrates, and its subsequent monitoring after infection. Various organs of the plant during the vegetative stage and until the beginning of the reproductive stage, were evaluated. In both inoculation models, the bacteria was maintained in the plant as an endophyte between $1{\times}10^1$ and $1{\times}10^5cfu$ of B. $glumae.g^{-1}$ of plant throughout the vegetative stage. An increase of bacterial population towards initiation of the panicle was observed, and in the maturity of the grain, an endophyte population was identified in the flag leaf at $1{\times}10^6cfu$ of B. $glumae.g^{-1}$ fresh weight of rice plant, conducting towards the symptoms of bacterial panicle blight. The results found, suggest that B. glumae in rice plants developed from infected seeds or from the substrate, can colonize seedlings, establishing and maintaining a bacterial population over time, using rice plants as habitat to survive endophyticly until formation of bacterial panicle blight symptoms.

• 식물병연구
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• 제10권2호
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• pp.112-116
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• 2004

보통답에서 마른 상태의 잔재볏짚이 젖은 상태의 볏짚에서 보다 병원균의 분리빈도가 높았고, 염해답에서는 중간정도 젖은 상태의 볏짚과 완전히 젖은 상태의 볏짚에서 병원균의 분리빈도가 높았으며, 보통답보다는 염해답에서 병원균의 분리빈도가 대체적으로 높았다. 벼깨씨무늬병균은 벼에 포자현탁액을 접종한 후 습실상에서 6시간 유지시키면 침입이 되어 발병이 되었으며, 추청벼에서는 14시간, 대산벼와 Tetep에서는 24시간에 최대 발병율을 나타냈다. 엽령이 많은묘(63일묘)가 엽령이 어린묘(21일-49일묘)보다 병에 대해 감수성이었다. 병반은 품종과 엽위에 관계없이 비교적 고르게 분포되었으며, 대산벼와 추청벼에서 상위에 있는 제 5엽이 하위에 있는 잎들보다 감수성이 높은 경향이었으며, Tetep에서는 뚜렷한 경향이 나타나지 않았으나, 하위엽에서 병반수가 많은 경향이었다. 광의 조사와 발병과의 관계에서는 암처리한 벼가 온실조건 3,000 Lux와 6,000 Lux의 광을 조사한 벼보다 발병정도가 현저히 적은 경향이었다.

• 한국응용곤충학회지
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• 제3권
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• pp.21-25
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• 1964

1. 본 시험은 이병된 식물의 잔재물 또는 토양중에 있는 맥류적미병균(Gibberella zeae (Mont.) Sacc.)이 14종의 작물유묘에 미치는 병원성을 검정하고자 하였다. 2. 이들 작물은 병원균을 인공적으로 접종한 토양, 그리고 맥류적미병의 발생이 자연적으로 심했던 곳과 경했던 곳의 토양에 공시하여 본균에 대한 이병성을 검정하였다. 3. 인공접종시험에 있어서 보리, 밀, 호밀, 콩, 벼, 메밀, 옥수수, 목화, 녹두는 이병성이었고, 팥, 참깨, 수수, 무, 배추 등은 저항성을 나타내었다. 4. 인공접종시험에 있어서, 이병성작물의 발아율은 벼, 옥수수, 목화를 제외하고 접종토양과 배접종토양에 있어 현저한 유의차가 있었다. 아시전립고는 보리, 옥수수에서만, 아시후립고는 호밀, 밀, 벼, 메밀, 보리, 옥수수에서 일어났다. 이병성작물의 대부분은 제2차근이 거의 부패하였고 제1차근도 부패 내지 변색되어 있었다. 이병성작물은 초장이 접종토양과 비접종토양에 있어 현저한 유의차가 있었다. 5. 자연상태에서 맥류적미병의 발생이 심했던 곳과 경했던 곳의 토양에 보리, 밀, 호밀을 파종하였으나 본균에 의한 침해나 영향을 발견할 수 없었다.

• 한국식물병리학회지
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• 제11권1호
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• pp.94-97
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• 1995

In 1994, an abnormal rice growth was observed in a 0.5-ha scale farmer's field located at Chogye-Myeon, Hapcheon-Gun, Gyeongnam Province where rice cv. Hwayeongbyeo was seeded directly in dry paddy field conditions. The major symptoms were less stands per acreage, short leaf length, and hypertrophy of root tip portion. The disorder was identified as rice seeding bight caused by Rhizopus sp. The average plant stand per m2 in the infested field was 108, while it was 375 in the normal field, and leaf growth was retarded to less than one-third of healthy plant. The average leaf lengths of infected and healthy seedlings were 12.8cm and 38.9cm, respectively. When the infected seedlings were transplanted to pots, flooded-soil conditions developed no new root growth but upland conditions allowed 11.2 new roots emerging. The length of newly emerged root in infested soil was 5.3cm in upland and 7.1cm in intermediate flooding conditions. However, it was 10.9cm in non-infested soil with intermediate flooding conditions. When the plants were matured, the stem length of infected plants was reduced slightly as compared to normal plants, whereas the length of panicle was not significantly different between infected and healthy plants. The number of panicle per plant, however, greatly different with variation of infection degree. Grain quality such as the number of complete and incomplete grains per panicle, the complete grain weight per panicle, and the weight of 1000 grains was not significantly different.

• Animal cells and systems
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• 제10권1호
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• pp.21-25
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• 2006

In the present study, Dravya-an organic compound used for seed treatment along with the common fungicides to test its compatibility in the management of Alternaria padwickii in paddy. Dravya (a sea weed extract) was found highly compatible with fungicides like Bavistin and Dithane M-45. Incidence of Alternaria padwickii and Bipolaris oryzae was also reduced to a greater extent in the paddy seed samples of Dravya treatment. On the other hand, it also enhanced the seed germination and seedling vigour. Seedlings of treated samples also showed enhanced activity of peroxidase upon challenge inoculation with Alternaria padwickii. The enzyme activity in the seedlings challenged with the pathogen was two fold more over control. The suppression in disease incidence in growing plants indicated the promising effect of Dravya and Dithane M-45 under green- house conditions.

• 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).