• 한국토양비료학회지
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• 제14권2호
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• pp.76-82
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• 1981

수도체의 영업조건(營業條件) 특히 생육시기별(生育時期別) 규산(珪酸)의 공급조건(供給條件)과 도열병 발병(發病)과의 실계를 밝히고자 밀양(密陽)23호와 낙동(洛東)벼 (밀양(密陽)15호)를 공시(供試)하여 질소수준(窒素水準)을 달리하고 생육시기별(生育時期別) 규산(珪酸)의 공급조건(供給條件)을 달리하여 수경시험(水耕試驗)을 실시(實施)한 결과(結果)를 요약(要約)하연 다음과 같다. 1. 규산(珪酸) 시용(施用)으로 도열병 이병률(罹病率)은 현저(顯著)히 감소(減少)하였으며 이는 주(主)로 수도분중 규산함량(珪酸含量)의 증가와 질소(窒素) 함량(含量)의 감소(減少)에 기인(起因)되었다. 2. 유수형성기(幼穗形成期) 이후(以後)의 규산(珪酸) 시용(施用)으로 목도열병 이병수률(罹病穗率)은 현저(顯著)히 감소(減少)하여 규산(珪酸) 추비효과(追肥效果)의 가능성(可能性)을 보였다. 3. 규산(珪酸)의 도열병 억제효과(抑制效果)는 잎도열병보다 목도열병에서 뚜렷했다.

• 한국토양비료학회지
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• 제18권4호
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• pp.386-391
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• 1985

사질답(砂質畓)에서 시비방법(施肥方法)과 질소시비량(窒素施肥量)을 달리 하였을 때 도열병발생(稻熱病發生)에 미치는 영향(影響)을 구명(究明)하기 위(爲)하여 전국(全國) 8개도(個道)와 인근(燐近)3요소(要素) 시험지(試驗地)에서 시험(試驗)한 결과(結果)를 요약(要約)하면 다음과 같다. 가. 잎도열병과 목도열병 이 병율은 질소 20kg/10a 수준까지 고도의 유의성(有意性)있는 증가를 보였다. 나. 잎도열병(稻熱病)과 목도열병(稻熱病) 발생률(發生率)과의 관계(關係)는 질소(窒素)20kg/10a 수준(水準)에서 정(正)의 상관(相關)이었다. 다. 목도열병(稻熱病)의 방제효과는 발병율(發病率)을 93.5~62.5%까지 방제(防除)가 가능(可能)하였다. 라. 인근(燐近) 3요소(要素) 시험구(試驗區)에서 최고수량(最高收量)은 무방제(無防除)의 경우(境遇) 정조(精租) 604kg/10a, 방제구(防除區)에서 719kg/10a였으며 그 때의 질소적정시비량(窒素適正施肥量)은 각각(各各) 14.5 및 18.5kg이었다. 마. 같은 3요소(要素) 시험지(試驗地)에서 정조수량(精租收量)은 목도열병(稻熱病) 이병수준(罹病收準)이 15.6% 이상(以上)에서는 감수(減收)되었다.

• 한국식물병리학회지
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• 제10권2호
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• pp.78-82
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• 1994

Unusually severe rice blast epidemic sweeped over the rice growing area in Gyeongnam Province and elsewhere in 1993. Leaf blast infection was reached to 33,133 ha, which is about 24.5% of total paddy area and neck blast infection was apparent throughout 4,421 ha. Major factors affecting such an unusual epidemic appeared to be as follow: Firstly, low temperature, frequent rainfall and coincidentally insufficient duration of sunshine through July and August; Secondly, most cultivars possessing low levels of field resistance were cultivated in wide areas: Thirdly, blast fungus population was enough for successive infection under optimum weather condition and most races distributed in field were able to infect most cultivars.

• 농업과학연구
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• 제10권1호
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• pp.84-89
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• 1983

이삭도열병(病) 방제(防除)를 위(爲)한 IBP 17% 입제(粒劑)의 최적살포시기(最適撒布時期) 및 살포량(撒布量)을 구명(究明)하기 위해 실시(實施)한 이 실험(實驗)의 결과(結果)는 아래와 같다. IBP 입제(粒劑)의 최적살포시기(最適撒布時期)는 출수(出穗) 15~20일전(日前)쯤이 가장 효과적(效果的)인 경향이었다. 최적살포량(最適撒布量)은 4kg/10a 수준(水準)이었으나 살포시기(撒布時期)와 살포량(撒布量)이 복합적(複合的)으로 고려되어야 한다. 1회(回)의 IBP 유제살포(乳劑撒布)와 입제살포(粒劑撒布)로 도열병(病)의 완전방제(完全防除)는 불가능(不可能)하기 때문에 출수(出穗) 전후(前後)에 1~2회(回)의 추가약제살포(追加藥劑撒布)가 불가피하다.

• 한국작물학회지
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• 제24권1호
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• pp.1-10
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• 1979

In order to investigate the causes of epidemic out break of rice blast disease in 1978, investigations were undertaken in respect of climatic conditions, variety, cultural practice and plant pathology. During 1978, especially in August at heading time, it was higher temperature and humidity, higher frequency and amount of rainfall, lower amount of sunshine and solar radiation than less blast infested years. Nitrogen content in rice plant was higher than previous years. Acreage increase of semi-dwarf varieties brought about a result of proportional increase of new blast races which are able to infect the semi-dwarf varieties. It was concluded that those conditions mentioned above might have caused the result of severe neck blast disease in rice varieties in Korea, 1978.

• The Plant Pathology Journal
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• 제21권2호
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• pp.87-92
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• 2005

The structural differences between healthy and diseasedpanicle necks caused by Pyricularia oryzae were observed using electron-microscope. In the diseased panicle neck, the infection hyphae of the rice blast pathogen grew through the sclerenchymatous fiber tissue and reached to the central internal lacuna. Since the pathogen grew through the sclerenchymatous fiber tissues, the vascular bundle composed with xylem and phloem had been destroyed and finally the nutrients from the leaf and stem were not able to be transported into the grains. Infection of panicle base by the blast pathogen until 20 days after heading caused more than 50% of yield loss in both Jinmibyeo and Chucheongbyeo. There was a positive correlation between incidence of the panicle blast and rice yield losses. The regression equations between incidence of the panicle blast and yield losses were y= -3.61+496.7 ($R^2$=0.70) in Jinmibyeoand y=-3.93+520.2 ($R^2$=0.82) in Juanbyeo. The panicleblast caused deterioration of grain quality. Healthy grain rate was reduced by increase of panicle blast infection.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2000년도 추계 학술발표회
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• pp.33.2-33
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• 2000

• 한국식물병리학회지
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• 제13권2호
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• pp.90-94
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• 1997

Interaction of races of rice blast fungus and cultivars has been evaluated. Dongjinbyeo was infected by four KJ races and two KI races, while other varieties were susceptible to four to six KJ or KI races. Among the single spores reisolated from the leaf blast lesion of Dongjinbyeo after mixed inoculation of 10 races, 63% was race KJ-301 which produced a small number and small size lesions, while 30% was race KI-313 which produced a large number of lesions. However, 93% of single spores reisolated from Palgongbyeo was a highly virulent race KJ-105. On the other hand, all the races were equally reisolated from the susceptible cultivar Jinmibyeo. Frequency of races isolated from the naturally infected leaf blast lesions in the field was similar to that of reisolated races from the cultivars inoculated with 10 mixed races in the greenhouse. However, 30% of single spores isolated from the naturally infected Dongjinbyeo was race KI-329 ut ace KI-313 was not detected. Genetic relationship of the isolates collected from leaf and neck blast fungus of Jinmibyeo and Nakdongbyeo showed specific bands on RFLP-P64, However, their genetic similarity was 80%.

• The Plant Pathology Journal
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• 제36권3호
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• pp.231-243
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• 2020

Rice blast, caused by Magnaporthe oryzae, is one of the most destructive rice diseases worldwide. The aim of this study was to screen bacterial isolates to efficiently prevent the occurrence of rice blast. A total of 232 bacterial isolates were extracted from nonrhizospheric rice soil and were screened for antifungal activity against M. oryzae using a leaf segment assay. Strains S170 and S9 showed significant antagonistic activity against M. oryzae in vitro and in leaf disk assays, and controlled M. oryzae infection under greenhouse conditions. The results showed that strains S170 and S9 could effectively control rice leaf blast and panicle neck blast after five spray treatments in field. This suggested that the bacterial strains S170 and S9 were valuable and promising for the biocontrol of rice disease caused by M. oryzae. Based on 16S rDNA, and gyrA and gyrB gene sequence analyses, S170 and S9 were identified as Bacillus amyloliquefaciens and B. pumilus, respectively. The research also demonstrated that B. amyloliquefaciens S170 and B. pumilus S9 could colonize rice plants to prevent pathogenic infection and evidently suppressed plant disease caused by 11 other plant pathogenic fungi. This is the first study to demonstrate that B. amyloliquefaciens and B. pumilus isolated from nonrhizospheric rice soil are capable of recolonizing internal rice stem tissues.

• 한국식물병리학회지
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• 제11권4호
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• pp.348-352
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• 1995

Severe gray mold neck rot of onion occurred in most farmers' fields in the southern part of Korea, and 20∼50% of onions were infected by the disease at Goheung, Chonnam, in 1994. Symptoms of the disease appeared on the lower leaves near the soil surface in late February. The symptoms initially appeared as yellowish blotch with compact gray mold on the surface of the infected leaves and developed to blast of the aboveground parts of onions. As brown to dark brown symptoms progressed around the necks of onion later, the bulbs were rotting gradually. Botrytis sp. repeatedly isolated from the lesions produced the typical symptom on the neck of healthy onion 7 days after wound inoculation of conidial suspension of the fungus. The fungus reisolated from the bulbs was identified as Botrytis allii Munn based on the morphological and cultural characteristics and pathogenicity. This is first report of a gray mold neck rot of onion in Korea.