• 한국작물학회지
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• 제46권1호
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• pp.47-52
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• 2001

In order to develop more stable seedling stand method in wet direct rice seeding culture, the effect of making the drainage ditches was studied in both methods of broadcast seeding on floody paddy surface and puddled-soil drill seeding. In a broadcast seeding on floody paddy surface, the ditching after seeding using a tractor or small ditch maker improved the seedling stand, and reduced the floating seedling and herbicide injury by accelerating the drainage. Suitable ditching time was at 2 days after seeding (DAS) for the tractor and at 3 DAS for the ditch maker. In the puddled-soil drill rice seeding culture, the ditching before seeding with a ditch maker at 3 days after draining effectively improved the seedling stand due to quick draining through well formed the seeding furrows. In the puddled-soil drill seeding, seedling stand number showed higher in both ditching plots synchronized with seeding compared with both only draining treatment at 1 DAS without ditching and the flooding plot condition for 6 DAS. And the suitable ditching depth was 6 cm, as considered the ditching status and drained status. These results suggest that the ditching in wet direct rice seeding is an resonable practice for improving the seedling stand through the accelerating drainage of field.

• 한국작물학회지
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• 제52권3호
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• pp.249-258
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• 2007

Experiments were conducted with aims to (1) estimate the biomass yield potential, (2) characterize the biomass and digestible dry matter production, and (3) reveal the characteristic seedling establishment of a whole crop rice variety, Nogyangbyeo, in dry- and wet-seeded rice. Maximum aboveground total biomass of Nogyangbyeo was 18 t $ha^{-1}$ in dry-seeded rice and 20 t $ha^{-1}$ in wet-seeded rice. Biomass yield potential of Nogyangbyeo was lower than that of Dasanbyeo. Comparatively, Nogyangbyeo was straw-dependent and Dasanbyeo was grain-dependent for biomass accumulation. Percentage of digestible dry matter (DDM) was higher in panicles than straw. Digestible dry matter yield was determined mainly by biomass yield rather than DDM percentage. Number of seedling establishment in Nogyangbyeo was $73m^{-2}$ in dry-seeded rice and $109m^{-2}$ in wet-seeded rice. Poor seedling establishment of dry-seeded Nogyangbyeo in the field condition was the result of low seed germination under low temperature and poor seedling emergence by deep sowing. Low seedling emergence rate of Nogyangbyeo was attributed mainly to slow elongation growth by slow leaf development and partly to mesocotyl and 1st internode lengths, not to genetically defined leaf length. The slow elongation growth of Nogyangbyeo was the same even in the high daily mean temperature of $24^{\circ}C$. Results suggest DDM yield in rice can be improved simply by increasing biomass and whole crop rice varieties should be adaptable to direct-seeding.

• 한국작물학회지
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• 제57권2호
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• pp.166-170
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• 2012

본 연구는 신간척지에서 벼 기계이앙재배시 염 피해가 적으면서 안정적인 쌀수량 확보를 위하여 모 종류를 어린모, 치묘, 중묘, 폿트묘로 새로 조성된 간척지인 새만금 계화포장에 이앙하여 수행한 내용을 요약하면 다음과 같다. 1. 2년 평균 토양염농도는 이앙전 0.16%에서 환수후 이앙 직후에는 0.04%로 낮아졌다. 2. 모 종류별 출수기는 폿트묘 이앙이 8월 14일인데 비해중묘이앙은 2일, 치묘이앙은 3일, 어린모이앙은 5일 늦게 출수되었다. 3. 도복관련형질에서 중묘이앙이 도복지수가 가장 높아 포장도복 역시 중묘이앙이 반도복 정도 되었다. 4. 수량구성요소를 보면 이앙모 종류별 등숙비율과 현미천립중은 비슷하였고, 주당수수는 치묘>어린모>폿트묘>중묘이앙 순으로 많았으며, 쌀수량은 어린모=치묘>폿트묘>중묘이앙 순으로 많았다. 5. 이앙모 종류별 쌀 품질에서 완전립비율은 치묘>중묘=어린모>폿트묘 순으로 높았고, 아밀로스함량과 단백질 함량은 이앙모 종류간 차이가 없었다. 결론적으로 새로 조성된 간척지에서 벼를 기계이앙재배할 때 안정적인 쌀 수량 확보를 위한 적정 이앙모는 어린모와 치묘가 적합하다고 판단된다.

• 한국작물학회지
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• 제7권1호
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• pp.93-96
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• 1969

본 실험은 기상재해로 인한 극만앙의 경우 합리적인 저묘방법을 구명하기 위하여 행하여 졌던바 그결과를 요약하면 다음과 같다. 1. 경영적인 면에서 어떠한 저묘방법도 7월 20일 이후 이앙의 경우에는 효과를 기대할수 없다. 2. 이앙후의 수도생육은 건묘구가 가장 좋았고 다음이 비닐저묘상처리구 였으며 전엽처리나 묘솎음처리는 묘의 노화방지에 거의 효과가 인정되지 않았다. 3. 수도의 현미수량은 7월 20일 이앙의 경우 건묘구 (378kg/10a)에서 가장 높았고 다음이 비빌저묘상처리구(약280kg/10a)였으며 7월 30일 이앙의 경우에는 건묘구에서는 222kg/10a로서 가장 높았으나 그 외 다른 처리구에서는 모두 90kg/10a미만이었다.

• 한국작물학회지
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• 제51권4호
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• pp.362-368
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• 2006

A pot experiment was conducted to investigate the effects of soil burial depth on seedling emergences of rice (Oryza sativa) and Echinochloa spp. and to model such effects for mathematical prediction of seedling emergences. When the Gompertz curve was fitted at each soil depth, the parameter C decreased in a logistic form with increasing soil depth, while the parameter M increased in an exponential form and the parameter B appeared to be constant. The Gompertz curve was combined by incorporating the logistic model for the parameter C, the exponential model for the parameter M, and the constant for the parameter B. This combined model well described seedling emergence of rice and Echinochloa species as influenced by soil burial depth and predicted seedling emergence at a given time after sowing and a soil burial depth. Thus, the combined model can be used to simulate seedling emergence of crop sown in different soil depths and weeds present in various soil depths.

• 한국작물학회지
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• 제44권4호
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• pp.309-315
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• 1999

Rice seedling test was conducted to check the loging tolerance at ripening stage through evaluating the root characters. Thirteen Korean and foreign rice cultivars with direct seeding adaptable or high quality characteristics were grown in a cell pot and under submerged paddy. The root characters and pushing resistance of rice hill were determined at seedling and ripening stage, respectively. The diameter of crown root at the 7th and 8th leaf stages was thicker in lodging tolerance cultivars than those of others and showed significant-positive correlation with both pushing resistance and crown root diameter of mature plants. Also, the tensile strength of crown root at the 7th and 8th leaf stage showed highly positive correlation with the tensile strength of crown root of mature plants. The number of crown root at 7th leaf stage was significant-positively correlated with that of mature plant. The diameter of seminal root was not significantly correlated with the diameter of crown root throughout the whole growth stage. These results indicate that the diameter, tensile strength and number of crown root associated with root lodging tolerance can be detected with the seedling at about 7th or 8th leaf stage, and the seedling test using the cell pot is an useful and practical method to select lodging tolerant cultivars or lines of rice based on root characters, especially diameter of crown root.

• The Plant Pathology Journal
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• 제24권1호
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• pp.58-62
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• 2008

Utilization of carbon sources by Bacillus cereus D324, a biological control agent, and Pythium species, which causes rice seedling disease, was studied with the objective of increasing the efficacy of biological control by providing the biological control agent with specific beneficial carbon sources. D-galactose, D-sorbitol, and D-mannitol were poor carbon sources for Pythium spp. growth but were good for B. cereus D324 growth. Growth in a growth chamber of rice seeds coated with B. cereus D324 amended with specific carbon sources, such as D-galactose and D-sorbitol, showed significantly enhanced seedling emergence compared to seeds coated only with B. cereus D324. Field trials showed that both seedling emergence and yield increased, when the above specific carbon sources were added to B. cereus D324 in seed coating formulations. This result indicated that amending seed coating formulations with specific carbon sources could significantly increase seedling emergence and yield in the field.

• 한국작물학회지
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• 제38권6호
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• pp.545-553
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• 1993

벼 기계이앙을 위한 어린모 육묘에서 뿌리엉킴촉진에 탁원한 효과가 있는 metalaxyl의 묘 뿌리분화 및 신장생장에 관한 일부 생리적 기작을 밝히고자 metalaxyl 침지처리에 따른 어린모의 근활력, 발근력, 아미노산 함량 변화, 광합성 및 엽록소함량등을 조사ㆍ분석한 결과는 다음과 같다. 1. metalaxyl(25%, 수화제) 200ppm에 침지처리한 어린모는 무처리에 비하여 전육묘기간중에 근활력이 높았으며 특히 파종후 10～13일에 현저하게 높았다. 2. metalaxyl 200ppm에 종자를 침지처리한 어린모에서 재발생된 관근의 길이는 무처리보다 유의적으로 길었으며, 뿌리의 신장을 촉진시켰다. 3. metalaxyl 200ppm에 종자를 침지처리한 어린모에서 재발생된 관근의 수는 무처리와 비슷한였으나, 관근에서 발생된 분지근(측근)의 수는 2～3배 증가되어 분기근의 분화를 촉진시켰다. 4. 어린모 뿌리의 alanine함량은 metalaxyl처리에 의하여 현저히 증가되었으며, alanine 함량과 근활력, 또 metalaxyl 농도와 분지근수 간에는 정의 상관관계가 있었다. 5. metalaxyl 침지처리는 어린모 뿌리에서 거의 모든 종류의 아니노산 함량을 증가시켰다. 6. metalaxyl처리는 어린모 체내의 엽록소 및 전질소 함량을 높이고, 광합성량을 증가시켰다.

• The Plant Pathology Journal
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• 제37권2호
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• pp.200-203
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• 2021

Rice blast caused by the filamentous fungus Magnaporthe oryzae, is arguably the most devastating rice disease worldwide. Development of a high-throughput and reliable field blast resistance evaluation system is essential for resistant germplasm screening, resistance genes identification and resistant varieties breeding. However, the occurrence of rice blast in paddy field is easily affected by various factors, particularly lack of sufficient inoculum, which always leads to the non-uniform occurrence and reduced disease severity. Here, we described a procedure for adequately inducing the occurrence of rice seedling blast in paddy field, which involves pretreatment of diseased straw, initiation of seedling blast for the first batch of spreader population, inducing the occurrence of the second batch of spreader population and test materials. This procedure enables uniform and consistent infection, which facilitates efficient and accurate assessment of seedling blast resistance for diverse rice materials.

• 한국작물학회지
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• 제38권4호
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• pp.360-365
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• 1993

벼 기계이앙 어린모 육묘시 생장조절제가 묘의 초장신장 촉진에 미치는 효과를 구명하기 위하여 화성벼를 공시하고 6가지의 생장조절제를 사용하여 종자침종 효과와 6가지의 생장조절제를 사용하여 종자침종 효과와 묘 생장을 조사하여 다음과 같은 결과를 얻었다. 1. Gibberellin과 Metalaxyl은 어린모의 초장신장을 촉진시켰으며, Tetracycle은 초장을 억제하였다. 2. Gibberellin의 엽면분무처리가 종자침종처리보다 어린모의 초장신장에 더 효과적이었다. 3. 어린모의 초장신장 촉진을 위한 Gibberellin의 엽면분무처리의 적정농도는 약 10ppm이었다. 4. Gibberellin의 엽면분무의 적정처리시기는 파종후 3～4일 이었다.