• 한국작물학회지
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• 제21권2호
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• pp.222-232
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• 1976

경기도 부평군 소사(부천)에 가을 보리 품종 "칠보" 를 그리고 경북 칠곡군 동명에 품종 "제천 5초"를 각각 재식하고 각 지구에 보비 및 배비구를 설치하여 ethylene깨스 발생제인 Ethrel과 dl-methionine의 단응 또는 혼용으로 농도별 엽면살포를 하여 다음 결과를 얻었다. 1. Ethrel은 보리초장을 작게 하는데 그 농도가 더함에 따라서 더욱 작아졌으며 이것은 지엽에서 이삭의 기부까지의 길이 즉 출수도가 작아짐으로서 이루어진 것이다. 2. 보리의 초장이 작을수록 도복은 적었으나 수장과 1000립중이 따라서 적어지며 결국 종실중 수량이 감소되었다. 3. 질소의 보비 및 배비의 무처리는 모두 도복되었는데 Ethrel 500ppm처리에서는 전혀 도복을 볼 수 없었고 도복된 무처리에 비하여 약 10%증수를 나타내었다. 4. 배비의 효과는 보비보다 초장을 좀더 길게하는 데 있었고 배비가 오히려 보비보다 수량이 적은 편이였다. 5. Ethrel보완제로서의 dl-methionine처리는 보리의 왜화효과에 영향을 주지 않았으며 오히려 감수를 초래하였다. 우리나라 현 보리생산과 경제성의 관념에 입각하여 ethylene에 의한 왜화재배로 다비재배의 가능성과 증수재배의 전망을 논의하였다.능성과 증수재배의 전망을 논의하였다.

• 한국환경농학회지
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• 제24권2호
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• pp.185-190
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• 2005

일부 농가에서 이용하고 있는 기능성 쌀 생산 농자재인 게 껍질, 견운모 및 숯 분말의 시용이 벼의 생육, 수량 및 쌀의 품질에 미치는 영향을 구명하고자 본 실험을 실시하였다. 게 껍질 분말 시용구는 다른 처리에 비하여 분얼수, 이삭수, 엽면적지수, 식물체의 질소함량을 증가시켰으나 등숙율은 낮았고, 백미수량은 차이가 없었다. 미질은 게 껍질 분말 시용구에서 완전미 비율과 Toyo 식미치는 낮았고, 분상질미 비율, 단백질 함량은 높았다. 견운모와 숯 분말 처리는 벼의 생육, 수량 및 수량구성요소, 쌀의 품질은 무처리와 차이가 없었고, 단백질 함량는 무처리보다 높았으나 Toyo 식미치는 낮았다.

• 한국작물학회지
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• 제47권4호
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• pp.273-278
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• 2002

An efficient low-input system (LIS) for fertiliser use in rice cultivation is necessary to reduce fossil energy use and pollution. Japanese people like Japonica rice, especially cv. Koshihikari. However, it has very low lodging resistance in Japanese weather condition. Our objective was to develop a LIS with the minimum sacrifice of grain yield in rice. Koshihikari was grown using conventional fertilization as a control (CON) with 4 g N $m^{-2}$., 8g $P_2$ $O_{5}$ $m^{-2}$ and 8 g $K_2$O $m^{-2}$ as a basal fertilizer dressing. It was compared with a low fertilizer treatment (LF) with only 4 g $P_2$ $O_{5}$ $m^{-2}$ as a basal dressing in the first year and no basal phosphorus fertilizer in the second year. Chopped rice straw was incorporated into the soil before the cropping season in both years. Fertilizer of 4 g N $m^{-2}$ was top-dressed at 15 days before heading in CON plots and 30 days before heading in LF plots in both years. Lodging was significantly less in LF than in CON plots, however, no rice straw effect was found in low fertilized condition. Grain yields in LF plots were reduced by 15-16% below those of CON plots. Lower yields in LF plots were associated with a reduced number of spikelets per unit area. However, big spikelet size was acquired in LF by 10 days earlier N top dressing than CON plots. A close relationship was found between spikelet numbers and N content of the plant at heading, and between grain yield or shoot dry weight and N content of the plant at maturity. Regardless of the fertilizer application methods, N use efficiency for the number of spikelets, final total dry matter and grain yield was essentially identical among fertilizer treatments. The reduced growth and yield in the LF plots resulted from low absorption of nitrogen. Conclusively, LIS can drastically reduce chemical fertilizer use and facilitate harvest operations by reducing lodging with some yield reduction..

• 한국작물학회지
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• 제53권spc호
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• pp.72-77
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• 2008

This study was carried out to determine the response of the rice yield and grain quality by rice leaf folder (RLF, Cnaphalocrocis medinalis G.) and identify the damages caused by different transplanting dates, nitrogen amounts and chlorophyll amounts (SPAD value) of rice leaf. As the damage degree of RLF was getting severer, the ripened grain rate and 1000-grain weight were decreased and due to the increasing of chalky rice rate the rate of head rice was reduced. Therefore, the yield of head rice was decreased by 36% in heavily damaged rice plant. Among the physicochemical characteristics, protein content of rice grain was increased but amylose content was reduced, consequently, the palatability was deteriorated in heavily damaged rice by RLF. The degree of damage of RLF was getting serious as transplanting date was delayed and as the amount of nitrogen was increased. In the relationship between the SPAD value and the damage degree of RLF, as the SPAD value was increased by nitrogen fertilizing, the damage degree was also increased exponential functionally.

• 한국작물학회지
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• 제44권2호
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• pp.106-111
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• 1999

To investigate the effects of planting density and nitrogen level on growth and yield potential of newly bred heavy panicle japonica rice with large grain (Iksan 435 and Iksan 438) or many spikelets per panicle(HR14022-21-8-4 and HR14022-21-8-6), four heavy panicle type rices and two many panicle type rices(Dongjinbyeo and Donganbyeo) as the checks were planted under standard planting density (30$\times$15 cm) and dense planting density (15$\times$15 cm) with two nitrogen levels of standard nitrogen level(110 kg h $a^{-1}$) and heavy nitrogen level(165 kg h $a^{-1}$). Effective tiller rate decreased in dense planting or heavy nitrogen, when compared to standard nitrogen and planting, while leaf area index and to dry weight increased in dense planting or heavy nitrogen. Tiller numbers and panicle numbers were more increased by dense planting than heavy nitrogen, whereas spikelet numbers were more increased by heavy nitrogen than dense planting. Ripened grain ratio was slightly lower only in dense planting. 1,000 grain weight in brown rice was not significantly different in dense planting or heavy nitrogen. Milled rice yield was highest in heavy nitrogen with standard planting for heavy panicle type rice, while yield for many panicle type rice was highest in heavy nitrogen with dense planting, suggesting that many panicle type rice possesses higher adapt-ability for dense planting than heavy panicle type rice. Path coefficient analysis revealed that top dry weight, spikelet number and grain weight were the greatest positive contributors to yield, whereas tiller number was negative to yield.d.

• Plant Resources
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• 제3권3호
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• pp.206-210
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• 2000

A total of 20 soybean recommended varieties which were developed until late 1980's in Korea was evaluated at Suwon. Comprehensive evaluation and correlation analysis were conducted on the agronomic characters. Great variations were found in these genotypes for branch number, pod number, and grain yield per plant. The variation in number of pods/plant ranged from 53 to 164, and in grain yield from 25.9 to 68.8 g. The coefficient of variation for most of the characters had a wide range. In correlation coefficient, grain yield per plant showed a positive phenotypic association with weight of pods, pod number of branches, and weight of stem. Multiple regression analysis was done to formulate selection criteria. It indicated that stout and medium-stature genotypes with more branches, resulting in varieties with more pods per plant but with medium-size seeds are available to obtain high-yielding varieties.

• 한국작물학회지
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• 제30권2호
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• pp.174-179
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• 1985

보리의 간장, 경수, 수장, 100입중, 개체당수수 수당입수, 수량등 7개 형질에 대한 광의의 유전역을 조사하고 형질들 간의 표현형상관, 유전상관, 환경상관을 조사하고 또 유전상관에 의해 형질들의 수량에 대한 직접 및 간접효과를 알기 위해 경노계수 분석을 해 본 결과는 다음과 같다. 1. 유전역은 간장이 0.923으로 가장 높았고 다음은 수장이 0.907로 역시 높았으며 수당입수, 수량, 100입중등도 상당히 높은 수치를 나타냈다. 그러나 경수는 0.179, 개체당수수는 0.147로서 상당히 낮은 유전력을 나타냈다. 2. 간장은 100입중과 고도의 유의성있는 표현형 상관이 있었으며 또 높은 유전상관을 보였다. 경수도 수수와의 사이에서 높은 표현형 상관과 유전상관을 보였고 수장은 입수와의 사이에서 높은 표현형 및 유전상관을 보였다. 수량은 수장, 100입중, 입수등과의 사이에서 고도의 유의성 있는 표현형상관을 보였고 또 높은 유전상관을 보였다. 3 . 경노계수 분석결과 간장은 수량에 대해서 직접효과가 없었으며 다른 형질을 통한 간접효과도 없었다. 경수는 직접효과가 다른 형질보다 가장 컸으며 수장과 100입중도 수량에의 영향이 비교적 강한 것으로 나타났다. 수수는 수량에 대해서 가장 큰 부의 직접효과를 보였다. 수수는 경수를 통해서 그리고 입수는 수수를 통해서 강한 간접효과를 보였으며 경수는 수수를 통해서 가장 큰 부의 간접효과를 보였다.

• 한국기계연구소 소보
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• 통권20호
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• pp.71-78
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• 1990

This investigation was undertaken to establish the technologies of grain refinement and modification, and to characterize material properties, essential for high quality aluminum alloy castings. Grain refinement seldom changed DAS and eutectic Si size, but largely decrease grain size. The variations of grain size induced by grain refinement had a great influence on the elongation without changes in the tensile strength or yield strength. The optimum Ti level lies between 0.1% and 0.16% to achieve the best possible mechanical properties. DAS and grain size were little affected, but eutectic Si size was greatly refined by modification. The variation of eutectic Si size had a great effect on the elongation, impact value, fracture toughness and fatigue crack propagation rate without changes in the tensile strength or yield strength. The Sr content of 0.015% is optimum to modification.

• 한국재료학회지
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• 제25권10호
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• pp.559-565
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• 2015

The ductile-brittle transition behavior of two austenitic Fe-18Cr-10Mn-N-C alloys with different grain sizes was investigated in this study. The alloys exhibited a ductile-brittle transition behavior because of an unusual brittle fracture at low temperatures unlike conventional austenitic alloys. The alloy specimens with a smaller grain size had a higher yield and tensile strengths than those with a larger grain size due to grain refinement strengthening. However, a decrease in the grain size deteriorated the low-temperature toughness by increasing the ductile-brittle transition temperature because nitrogen or carbon could enhance the effectiveness of the grain boundaries to overcome the thermal energy. It could be explained by the temperature dependence of the yield stress based on low-temperature tensile tests. In order to improve both the strength and toughness of austenitic Fe-Cr-Mn-N-C alloys with different chemical compositions and grain sizes, more systematic studies are required to understand the effect of the grain size on the mechanical properties in relation to the temperature sensitivity of yield and fracture stresses.

• 한국작물학회지
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• 제21권1호
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• pp.71-81
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• 1976

맥주맥의 육종에 있어서 곡립형질의 효율적인 선발자료를 얻고자 2조대맥 10품종을 공시하여 곡립형질의 유전력, 유전적 획득량, 상관관계, 경로계수등을 통계 유전학적으로 분석한 결과를 요약하면 다음과 같다. 1. 곡립형질들 중에서 곡피 (H=0.886), 분상질(H=0.848), 곡립형성비수(H=0.823)등은 유전력이 높고, 수량(H=0.526), 곡립폭(H=0.420)등은 유전역이 비교적 낮았다. 2. 기특되는 선발효율은 곡피(52.7%), 분상질(31.8%), 선입률(23.0%), 등이 높고, 곡립장(6.2%), 곡립폭(3.7%), 곡립후(8.7%) 등이 낮았다. 3. 맥주의 품질을 위하여 선발의 대상이되는 실용형질중 천립중, 분상질 Protein간의 상관관계는 다소유의성이 있었으나 곡립형질과 수량간의 상관관계는 유의성이 없었다. 4. 천립중, 곡피 및 수량의 선발은 이들에 대하여 직접효과가 큰 곡립후를 이용하여 간접적으로 선발하는 것이 효율적인 것으로 보였다. 5. 분상질 및 Protein을 위한 선발은 곡립후, 곡피 등과 수량간의 부의 간접효과를 개선하고 수량의 직접효과를 향상시키는 것이 유리할 것으로 보였다.