• 식물병과 농업
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• 제5권1호
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• pp.20-26
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• 1999

Ultraviolet light is required for the sporulation of Didymella bryoniae, a gummy stem blight fungus in cucurbits such as watermelon, melon, oriental melon, cucumber and pumpkin. In this experiment, the upper limit of wave length for the production of pycnidia of D. bryoniae was 365 nm - 375 nm. Two plastic houses were covered with either common transparent film (wave length longer than 225 nm is transmitted) or UV-absorbing film ( wave lenght shorter than 388 nm is absorbed). In both houses, seedlings inoculated with D. bryoniae were placed in the center of the house at 30 days after transplantation of watermelon (cv. Whanhoseong), and the disease incidences between the houses were compared until 80 days after transplantation. The number of disease lesions and incidence of pycnidia-producing lesions under the UV-absorbing film were reduced by 90% and 80%, respectively, compared to the common transparent film. The internode lengths of plants grown in the two houses were not significantly different, but the plants grown under the UV-absorbing film had longer vines and more leaves than plants under the common transparent film. However, fruit characters such as weight, length, width, rind thick and brix, were not different between the two houses. Occurrence of aphids was reduced in the UV-absorbing film, but those of mites or diseases (powdery mildew and sooty mold) were not different between the houses. These results suggest that disease incidence of gummy stem blight of watermelon in the greenhouse can be controlled by the use of UV-absorbing film.

• 한국작물학회지
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• 제35권2호
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• pp.132-136
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• 1990

수도 흰잎마름병(Xanthomonas campestris pv. oryzae) 병원세균(K1)의 조직내에서의 증식과 이동 그리고 수공을 통해 추출되는 병원세균의 농도를 조사한 결과를 요약하면 다음과 같다. 1. 저항성 품종에서는 접종 3일후에 약 $10^3$cfu/$\textrm{cm}^2$로 12일까지 큰 변화가 없었으나 리병성 품종에서는 접종 6일에 약 $10^4$cfu/$\textrm{cm}^2$에서 접종 12일에는 약 $10^{8}$-$10^{9}$cfu/$\textrm{cm}^2$로 계속 증식하였다. 2. 병원세균의 접종부위로부터 상, 하향 이동속도 및 증식속도는 상향이동이 약간 빠른 경향이었으며 리병성 품종에서 빠른 증식과 이동속도를 보여 저항성과 밀접한 관계가 있었다. 3. 병원세균의 증식 및 이동은 생육시기에 따른 차이는 없었다. 4. 감염된 잎의 수공을 통해 나오는 병원세균의 농도는 조직내에서 병원세균의 증식 및 이동과 일치하였으며 저항성과도 밀접한 관계가 있었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.265-265
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• 2017

This study was carried out to develop rice variety integrated with rice bacterial blight resistance gene and to know the information of major agronomic traits of developed variety. Advanced backcross Lines 21 having Xa3 and Xa21 gene cross from japonica cultivar Hwanggeumnuri and indica variety IRBB21. Days after seeding and culm length of ABLs21 were 108 days (Aug. 16) and 76 cm, respectively. Ripened grain rates was 87.4 %, which was similar to the parents. 1000 grain weight of brown rice of ABLs21 was 21.4g, which was lower than the donor parent. Milled rice yield of ABLs21 was 532 kg/10a, which was smaller than recurrent parent and higher than the donor parent. Grain length/width ratio of brown rice was form of japonica with short-ellipse and glossiness of cooked rice has japonica trait. Head rice rate showed a large difference compare to the donor parent and similar to the recurrent parent. ABLs21 would be useful genetic resources for resistance breeding program against bacterial blight.

• The Plant Pathology Journal
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• 제22권2호
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• pp.119-124
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• 2006

Kudzu vine(Pueraria montana var. lobata) is an invasive climbing woody vine that envelops trees and shrubs, pressing physically and shutting out sunlight, which needs to be controlled. Kudzu vine pathogens were surveyed as a way to seek its biocontrol agents in 2002. Occurrence of a bacterial halo blight disease of kudzu vine was observed at several localities in Korea including Euiwang and Suwon in Gyeonggi Province, Daejon, and Gochang and Buan in Jeonbuk Province. Symptoms of brown to black spots with a surrounding yellowish halo appeared from June and lasted till the rainy season without much expansion, but accompanying often leaf blight and defoliation. Isolated bacteria were identified as Pseudomonas syringae pv. phaseolicola based on physiological and cultural characteristics, Biolog, fatty acid and 16S rDNA sequencing analyses. In artificial inoculation test, these bacteria produced the same halo spot symptoms on kudzu vine and bean plants. They also induced hypersensitive responses (HR) on tobacco, tomato, and chili pepper leaves. This is the first report of a bacterial disease of kudzu vine in Korea, and the bacterial pathogen can be used as a biocontrol agent against the pest plant.

• 식물병연구
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• 제16권1호
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• pp.94-96
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• 2010

In May of 2004 through 2007, Leptosphaerulina leaf blight caused by Leptosphaerulina trifolii occurred on Kentucky bluegrass (Poa pratensis) at golf courses in Gangwon Province, Korea. Symptoms on the turfgrass caused by L. trifolii were leaf blights, dying from the leaf tip downwards to the crown, which appeared patches in the field because of local pockets of severely infected (blighted) grass. Perithecia were produced on old or weak leaves, including club-shaped asci, each of which contained 8 pale brown muriform ascospores with cross and longitudinal septa. Ascospores of the fungus isolated from the diseased leaf tissue and cultured on potato-dextrose agar (PDA) were muriform multicellular (composed of 3-6 cells) and $23.4-40.5{\times}7.8-15.6{\mu}m$ in size with 3-4 transverse and 0-3 longitudinal septa, which were morphologically identical to L. trifolii reported previously. DNA sequences of ribosomal RNA gene (internal transcribed spacer) of the fungus were homologous with similarity of 99% to those of L. trifolii isolates in GenBank database, confirming the identity of the causal agent of the disease. Pathogenicity of the fungus was also confirmed on the creeping bentgrass by Koch's postulates. This is first report of Leptosphaerulina leaf blight on turfgrass caused by L. trifolii in Korea.

• 식물병연구
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• 제15권1호
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• pp.17-22
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• 2009

본 연구는 미생물제의 이용에 의한 농약잔류 및 안정성문제 확보, 농약 살포량 및 살포횟수를 줄이는 방법을 개발하기 위하여 실시하였다. 미생물제와 살균제를 2회씩 14일 간격으로 교호 살포한 처리구에서 인삼 점무늬병 방제가는 68.34%$\sim$73.56%이 었고, 살균제를 교호 살포한 처리구에서 방제가는 87.00%$\sim$89.42%이었다. 미생물제와 살균제를 28일 간격으로 3회 혼합 교호 살포한 처리구에서는 2종류의 처리구(Com-12, Com-17)를 제외하고는 방제가가 74.53%$\sim$87.23%로 조합에 따라 우수한 방제효과를 나타냈다. 이상과 같이 미생물제와 살균제를 교호 또는 혼합 교호 처리하면 75.00%$\sim$83.33%의 농약 감량효과를 나타낼 수 있다.

• 식물병연구
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• 제7권2호
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• pp.112-115
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• 2001

2001년 경남 진주시 페튜니아 재배포장에서 Choanephora cucurbitarum에 의한 페튜니아 꽃썩음병이 발생하였다. 병징은 처음 꽃에 수침상으로 물려지면서 부패하고 급속히 진전되어 썩는다. 병반부위에서 검은색의 포자낭을 형성되고 오백색의 균사가 아주 많이 형성되어진다. 균사는 처음 흰색에서 연한 노란색을 띠며 포자낭은 대부분 구형이고 크기는 37.2~135.8 um이다. 단포자성포자는 갈색이고 단포로서 방추형, 타원형 또는 난형이며 크기는 10.4~22.4$\times$7.4~12.9 um이다. 포자낭포자는 갈색이고 단포로서 방추형, 타원형 또는 난형이며 크기는 13.7~23.5$\times$8.7~13.8 um이다. 양쪽 끝에 3개에서 수개의 부속사를 형성한다. 접합포자는 구형의 검은색이고 크기는 40.8~61.5 um이다. 균사생육 적온은 3$0^{\circ}C$이다. 이상과 같이 병원균의 균학적 특징과 병원성을 검정한 결과 이 병을 C. cucurbitarum에 의한 페튜니아 꽃썩음병으로 명명할 것을 제안하고자 한다

• 식물병연구
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• 제22권3호
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• pp.202-207
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• 2016

쌀은 세계에서 가장 중요한 작물 중의 하나이지만 충분한 비타민을 제공하지 않고, 벼 도열병과 흰잎마름병은 전 세계적으로 가장 큰 피해를 주고 있는 병해이다. 리보플라빈, 비타민 B2는 인간의 건강에 필수적인 영양소이며, 식물의 병원균에 대한 식물의 방어 활성화로 알려져 있다. 본 연구에서는 BioDoctor (Hyunnong Co., Ltd., Gokseong, Korea)라는 리보플라빈 기반 제품을 벼에 경엽살포했을 때, 주요 병해에 대한 저항성 유도 및 벼 체내에 비타민 함량이 증가되는지에 대한 가능성을 조사하였다. 온실검정에서 BioDoctor 제품 500배와 1,000배로 희석하여 경엽처리 결과 벼 도열병과 흰잎마름병에 대해 현저한 병 저항성을 유도하였다. 또한, BioDoctor를 처리한 알곡과 잎에서 통계적으로 유의한 수준으로 리보플라빈 함량이 검출되었다. 본 연구는 비타민인 리보플라빈이 함유된 BioDoctor가 벼 도열병과 흰잎마름병에 대해 병 저항성을 유도할 뿐만 아니라 쌀 곡류 내에 비타민 함량을 증가시키는 큰 잠재력을 가지고 있는 것으로 나타났다.

• 한국작물학회지
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• 제29권1호
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• pp.67-71
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• 1984

참깨의 주요병해인 역병에 대한 품종선발시험과 엽고병에 대한 발병조건을 구명하기 위하여 포장과 온실을 이용하여 시험을 실시한 결과 다음과 같은 중요 사항이 관찰되었다. 1. 역병에 대한 저항성품종은 Orotall. Suweon 7, Suweon 27 및 조치원이 저항성 품종으로 나타났고 PI 280795, IS 103도 다소 강한 품종으로 보였다. 2. 참깨 엽고병예 대한 발병률은 고온인 3$0^{\circ}C$에서 광의품종이 15%, 김포품종이 25%의 병반면적률을 보였고, 저온인 17$^{\circ}C$에서는 광의가 50%, 김포가 70%로 높은 이병성을 보였다. 3. 참깨 엽고병의 발병률은 다습조건에서 품종 광의가 55%, 김포가 80%의 병반면적률을 보였고. 건조조건에서는 광의와 김포품종이 각각 10%와 15%의 병반면적률을 보임으로서 다습조건에서 심한 발병현상을 보였다. 4. 엽령별 엽고병 발병정도를 보면 6엽기와 개화기에 각각 20%와 52.5%의 병반면적률을 보여 심한 발병현상을 보였고, 10엽기와 20엽기에는 이보다도 낮은 발병률을 보였다.

• Journal of Ginseng Research
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• 제5권1호
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• pp.73-84
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• 1981

Effect of environmental factors and host on the growth and outbreak of various ginseng diseases was reviewed Environmental lectors included hydrogen ion concentration, moisture content, temperature, nutrition, and microbiol populations. Age of the ginseng plants in relation to several ginseng disease occurrence was also included in order to formulate the effective control measure for ginseng diseases. Damping-off caused by Rhizoctonia, Pythium, and Phytophthora, greymold by Botrytis, sclerotinia by Scleretinia, and phytophthora blight caused by Phytophthora were usually prevalent during the early growing season of ginseng when temperature is below 20$^{\circ}C$, while anthrac se caused by Colletotrichum, alternaria blight by Alternaria, and bacterial soft rot by Erwinia were so during the latter growing season when temperature is above 25$^{\circ}C$. However, the root rot incited by Fnarium and Cylindrocarpon caused severe damages throughout the growing season. Growth range of the temperature for a pathogen was highly related to the corresponding disease outbreak. Hydrogen ion concentration was highly related to the outbreak of sclerotinia, root rot, and red rot. Most severe outbreak of those diseases where the soil acidity was pH 4.7, pH 6.5- 7.5, and pH6.0-6.5, respectively. Nitrogen content in the soil was also related to outbreak of root rot and red rot. More red rot occurred where NH,-nitrogen is above 30 ppm and more root rot obtained when excessive nitrogen fertilizer applied. Yellow necrosis apparently was related to magnesium especially its ratio with potassium or calcium content in a soil. Fusarium Population showed significant .relations to missing rate of ginseng Plants in a Implanting ginseng field, while that of total bacteria showed similar relations in all ginseng field, However, in six year old ginseng fields, the more the Streptomyces population was, the less the Fusarium obtained. Consequently, less missing rate observed in a field where Streptomyces population was high. Damping-off, root rot, Rhytophthor a blight were mose severe on the nursery and on 2-3 years old ginseng plants, whereas sclerotinia, and grey cod, alteraria blight, anthracnose were severe on 4-6 years old ginseng plants. Root rot caused by Fusarium and Erwinia, however, was also severe regardless of the age of the plants when the roots were injured. Therefore, for the effective control of ginseng root rot most careful control of the disease during the early year should be rendered.