• 한국주조공학회지
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• 제36권5호
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• pp.153-158
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• 2016

The lost foam casting process was used to fabricate Al-Si-Mg cast specimens, and the effects of the chemical composition and process variables on the tensile properties and the mold filling ability were investigated. Some porosity formation was observed in thick sections of the casting and better tensile properties were obtained for thin sections, presumably because of their lower porosity and the higher cooling rate. Tensile properties were not clearly enhanced by grain refining treatment with Ti; however, the elongation was significantly improved by Sr modification of the Al-Si-Mg alloy. The mold filling distance was generally proportional to the pouring temperature of the melt, and the distance was also increased by the addition of Ti.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.101-101
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• 2017

This study was carried out to improve yield potential of Tongil type rice variety based on QTLs analysis associated with yield component using a total of 386 rice recombinant inbred lines (RILs) derived from a cross between Tongil type high yield variety "Hanareum2" and Japonica variety "Unkwang". 384 SNP markers were used, and 241 of them (62.6%) were polymorphic between Hanareum2 and Unkwang. One hundred forty-four QTLs in 11 traits, such as heading days, were detected. Most of them were 21 QTLs associated with 1000 grain weight and the least was 8 QTLs associated with panicle number. The QTL, qDTH3-2 associated with days to heading was identified to delay heading date for 2.4~2.6 day. Eleven QTLs were associated with culm length. The QTL, qCL1-2 on chromosome 1, was identified to decrease culm length. A total of 16 QTLs were detected for panicle length. Three QTLs, qPL3, qPL6, and qPL7-1 were increased panicle length. Seven QTLs related to panicle number except qPN7 were increased the number of panicle. Four QTLs related to grain number per panicle, qGNP2-1, qGNP6, and qGNP7, were increased the number of grains. Three QTLs associated with grain filling rate, qGFR1, qGFR2-2, and qGFR7-1 were increased grain filling rate. Twelve QTLs associated with 1,000 grain weight. were increased the grain weight. Fourteen QTLs were identified associated with grain length. 10 QTLs, such as qGL1-1, were increasing grain. Fifteen QTLs associated with grain width were detected. The 8 QTLs, such as qGW1-1, were elongated grain width. Seventeen QTLs were associated with grain thickness, and ten QTLs of them were increased grain thickness. We need further study to develop introgression lines of each QTL to improve yield potential of Tongil type rice variety.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.124-124
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• 2022

Wheat (Triticum aestivum L.) is the major staple foods and is in increasing demand in the world. The elevated temperature due to changes in climate and environmental conditions is a major factor affecting wheat development and grain quality. The optimal temperature range for winter wheat is between 15~25℃, it is necessary to study the physiological characteristic of wheat according to the elevated temperature. This study presents the effect of elevated temperature on the yield and quality of two Korean bread wheat (Baekkang and Jokyoung) in a temperature gradient tunnel (TGT). Two bread wheat cultivars were grown in TGT at four different temperature conditions, i.e. TO control (near ambient temperature), T1 control+1℃, T2 control+2℃, T3 control+3℃. The period from sowing to heading stage has accelerated, while the growth properties including culm length, spike length and number of spike, have not changed by elevated temperature. On the contrary, the number of grains per spike and grain yield was reduced under T3 condition compared with that of control condition. In addition, the. The grain filling rate and grain maturity also accelerated by elevated temperature (T3). The elevating temperature has led to increasing protein and gluten contents, whereas causing reduction of total starch contents. These results are consistent with reduced expression of starch synthesis genes and increased gliadin synthesis or gluten metabolism genes during late grain filling period. Taken together, our results suggest that the elevated temperature (T3) leads to reduction in grain yield regulating number of grains/spike, whereas increasing the gluten content by regulating the expression of starch and gliadin-related genes or gluten metabolism process genes expression. Our results should be provide a useful physiological information for the heat stress response of wheat.

• 한국작물학회지
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• 제49권3호
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• pp.243-250
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• 2004

본 시험은 찰벼의 수량제한요인을 알아내기 위하여 찰$.$메근동질유전자 계통인 화청찰벼와 와청벼를 공시하여 공급부위(잎)와 수용부위(영화)의 조절이 등숙에 미치는 영향을 구명함으로써 찰벼의 수량증대를 위한 기초자료를 얻고자 수행하였으며, 그 결과는 다음과 같다. 1. 이삭당 총립중과 편균립중의 감소경향은 두 품종 모두 차엽처리구 ＜ 지엽처리구 ＜ 상위 1, 3엽처리구 ＜ 상위 1,2엽처리구 ＜ 상위 1, 2, 3엽처리구 순이었다. 상위 1, 2, 3엽 제거에 의한 총립중과 평균립중의 감소율은 화청찰벼에 비하여 화청벼에서 컸다. 2. 화청벼와 화청찰벼 모두 전엽처리에 의한 고밀도립비율과 등숙율이 2차지경보다 1차지경에서 높았다. 3. 화청벼와 화청찰벼 모두 영화의 절제처리에 의하여 이삭당 총립수와 총립중이 대조구에 비하여 감소한 반면 평균입중과 등숙율은 증가되었다. 대조구와 비교한 평균입중의 증가율은 1, 2차지경립 및 상$.$하위지경립의 절제구 모두에서 화청찰벼가 화청벼보다 높았다. 4. 영화의 조절의 의하여 두 품종 모두 고밀도립비율과 등숙립비율이 증가되었으며 고밀도립비율은 화청찰벼가 화청벼에 비하여 높았던 반면에, 등숙립비율은 화청벼에서 높은 결과를 보였다.

• 한국작물학회지
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• 제51권6호
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• pp.523-526
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• 2006

When $GA_{4}$ was applied to heading stage, it was examined to understand the change of plant hormones and starch during grain filling and ripening. Exogenous gibberellin caused a dramatic decrease in endogenous ABA content. Endogenous $GA_{4}$ content in both superior and inferior part was more promoted in $GA_{4}-treated$ rice grain than in the control. $GA_{1}$ content of an inferior part was not detected in the control and $GA_{4}-treated$ rice otherwise $GA_{4}$ was detected in all grain parts. Ripened grain rate in $GA_{4}-treated$ rice grain was lower than that of the control plant. Amylopectin from $GA_{4}-treated$ grain contained more very short chains with degree of polymerization (DP) between 4 and 8 than amylopectin from the control plant. It suggests strongly that fine structure of rice endosperm may be changed by exogenously applied $GA_{4}$ in rice plants.

• 한국작물학회지
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• 제28권4호
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• pp.451-457
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• 1983

영업생장말기, 수잉기, 출수개화기, 그리고 등숙초기의 네가지 주요한 생육기에 처리한 수분부족이 상위 3엽의 엽록소, 단백질유리 Proline과 상대팽압도의 변화와 몇가지 수량구성요소에 미치는 영향을 구명하기 위하여 과맥품종인 백동을 공시 수행하여 얻어진 결과를 요약하면 다음과 같다. 1. 수분부족처리에서 엽위별로 보면 지엽하위 1엽이 가장 높은 상대팽압도를 유지하여 엽록소와 단백질이 함량이 많았고, 유리Proline의 축적은 가장 적었다. 또한 생육기별로 보면 엽록소는 출수개화기에, 단백질은 수일기의 처리에서 가장 높았으며, 유리Proline은 수잉기의 처리에서 그 축적이 가장 낮았다. 2. 간장, 수장, 수당입수는 수잉기의 수분부족처리에서 감소영향이 가장 컸으며 천립중은 등숙초기에서, 그리고 종실의 크기는 수잉기와 그 이후 처리에서 가장 많이 감소되었다. 3. 종실의 단백질함량은 수분부족에 의해서 유의한 변화를 나타내지 않았으나 등숙초기에서 약간 감소한 경향이었다. 4. 불임율은 또한 수잉기와 출수개화기의 수분부족에서 심한 증가현상을 나타냈다. 5. 전반적으로 볼 때 생육단계별로는 수잉기에서, 그리고 엽위별로는 지엽 > 지엽하위 1엽 > 지엽하위 2엽의 순으로 수분부족의 영향이 컸다.

• 한국작물학회지
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• 제50권spc1호
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• pp.167-170
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• 2005

To obtain some information on the change of antioxidant components of seeds during grain filling stage as affected by the sowing dates, lignan compounds were investigated according to days of flowering under different sowing dates. Sesamin and sesamolin contents showed significantly different by days of flowering and varieties. Both of sesamin and sesamolin content increased after flowering and reached highest at 40 days of flowering, but they started to decrease thereafter, Sesamin and sesamolin contents of sesame seeds changed with sowing dates. Generally, late sowing date of May 30 showed relatively higher accumulation rate of sesamin and sesamolin contents rather than other sowing dates, but overall patterns were a little different by varieties and lignan compounds. In Yangbaekkae, sesamin and sesamolin contents showed relatively higher at sowing date of May 30, but Yanghuckkae showed higher sesamin and sesamolin contents till 20 days of flowering when sowing date of May 30, but it showed to change that both lignan contents were relatively higher under sowing date of May 10.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.229-229
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• 2017

This research study was conducted to analyze the characteristics of different rice cultivars in abnormal temperature conditions (low temperature) for ripening period abnormalities, and to investigate the physiological causes behind the abnormalities. Four Korean high quality japonica-type rice cultivars, Jinbu (JB), Junamjosaeng (JJ), Geumyoung (GY), Hwawang (HW) were used in the experiment. The following day after flowering, they were then moved into two phytotrons under natural daylight with 65% RH but controlled at different temperatures - one at $19/29^{\circ}C$ (night/day) and the other at $13/23^{\circ}C$ as the low - temperature study on ripening. For the cultivars at $13/23^{\circ}C$ (low temperature study), JB and JJ had a ripening rate of 93% which is similar to the ripening rates of cultivars at $19/29^{\circ}C$ at 45 days after heading (DAH). In contrast, GY and HW recorded lower ripening rates of 86% and 57% respectively. However, when the cultivars at $13/23^{\circ}C$ were harvested at 61 DAH (when the accumulated temperature reached $1100^{\circ}C$), the difference in ripening rates compared to the 4 cultivars of $19/29^{\circ}C$ harvested at 45 DAH was not obvious (JB 94%, JJ 97%, GY 97%, HW 88%). Starch content showed little difference among the 4 cultivars at different temperature conditions while amylose content was higher for cultivars at $13/23^{\circ}C$ compared to those at $19/29^{\circ}C$. In addition, the enzyme activities of starch biosynthesis were about 5~10 days slower in cultivars at $13/23^{\circ}C$ compared to cultivars at $19/29^{\circ}C$. The grain-filling rate showed highly significant correlations with the enzyme activities of Sucrose synthase ($R^2=0.70^{***}$), ADP glucose pyrophosphorylase ($R^2=0.63^{***}$), UDP glucose pyrophosphorylase ($R^2=0.36^{***}$), Starch synthase ($R^2=0.51^{***}$), and Starch branching enzyme ($R^2=0.59^{***}$). Among the enzymes, Sucrose synthase activity had the highest correlation coefficient with grain-filling rate. In conclusion, the activity of enzymes such as Sucrose synthase, UDP glucose pyrophosphorylase, ADP glucose pyrophosphorylase, Starch synthase, Starch branching enzyme in starch biosynthesis is proven to be highly related to the grain filling process. Notably, the decrease in the activity of Sucrose synthase and Starch branching enzyme and the late increase in ADP glucose pyrophosphorylase activity at low temperature in the ripening stage are considered to be disadvantageous as they delay ripening and increased amylose content.

• 한국작물학회지
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• 제62권3호
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• pp.166-171
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• 2017

본 실험은 적미의 재배에 있어서 고품질 고수량을 위한 적정이앙시기를 구명하기 위해 네 품종의 적미를 재료로 2015~2016년에 밀양에서 실시하였다. 1. 수량구성요소 중 이앙시기 변화에 따라 가장 크게 달라지는 요인은 등숙률이었고 6월 20일 이후 이앙하면 등숙률이 낮아져 현미수량이 하락하였다. 2. 6월 20일에 이앙했을 때 폴리페놀 함량과 현미수량을 종합한 폴리페놀 생산량이 2,341~3,349 g/10a로 가장 높았다. 3. 출수 후 30일간 평균온도가 낮을 수록 폴리페놀 함량은 증가하였으나 일정 수준 이하로 온도가 떨어지면 현미수량이 감소하였기 때문에 $22{\sim}23^{\circ}C$ 정도가 고품질 고수량 적미를 생산하기에 가장 적정한 온도였다. 4. 출수 후 30일간 평균온도가 $22{\sim}23^{\circ}C$가 되는 시점을 최적 출수기로 하고 출수소요적산온도를 $1,660^{\circ}C$로 하여 계산한 최적 이앙시기는 밀양시가 6월 18일~6월 24일 이었다. 경상남도 지역은 6월 중순에서 7월 초순, 경상북도 지역은 6월 초순에서 6월 중하순이 최적 이앙기였다.

• 한국작물학회지
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• 제49권3호
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• pp.160-166
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• 2004

벼 M/G RIL 162 계통에 대한 초기급속등숙율에 대한 이화학적특성 및 색차색도특성 변이에 대한 주성분분석 및 유전력분석의 결과를 요약하면 다음과 같다. 1. 초기급속등숙율이 41％ 이하인 계통군은 164계통중 74계통이었으며, 41∼60％의 계통군에는 32계통이 있었다. 또한, 초기급속등숙율이 빠른 계통군에 속하는 61∼80％사이에는 24계통이 있었으며, 초기급속등숙율이 매우 빠른 계통군으로 분류되는 81％ 이상인 계통은 32계통이 있었다. 2. 벼 M/G RIL 164계통에 대한 품종군별 이화학적특성을 보면, 초기급속등숙을이 40％ 이하인 계통군이 단백질 함량이 9.1％로 가장 높았으며, 지방산함량은 초기급속등숙율이 61∼80％의 계통군에서 26.5KOHmg/100g으로 가장 높게 나타났다. 또한, 곡립형태에 있어서 현미길이는 41∼60％사이의 초기급속등숙율을 보인 계통군이 5.40mm로 가장 짧았으며, 81％ 이상인 계통군이 1.80mm로 현미두께가 가장 두꺼웠으며, 현미의 형태를 나타내는 현미 길이/넓이 비에 있어서는 41∼60％사이의 계통군이 2.18로 나타났다. 3. 호화온도와 깊은 관련이 있는 알카리붕괴도에 있어서는 초기급속등숙율이 61∼80％사이가 3.40으로 가장 붕괴가 되지않는 계통군으로 나봤으며, 81％이상인 계통군은 4.31로서 붕괴가 가장 잘 되는 것으로 나타나 81％의 계통군이 호화온도가 낮은 것으로 나타났다. 4. 화학적특성, 색차색도특성 및 알카리붕괴도를 이용한 벼M/G RIL 164 계통에 대한 주성분분석의 결과 제 1주성분은 약 3.6개의 형질을 포함하고 있었으며, 제 2주성분은 약 2.1개의 형질을 포함하고 있는 것으로 밝혀졌다. 또한, 제 1주성분은 전체 변동에 대한 기여율은 약 36％이었으며, 제 4주성분까지의 전체 변동에 대한 누적 기여율은 86.4％로서 설명이 가능함을 알 수 있었다. 5. 벼 M/G RIL 164 계통의 품질평가치, 단백질함량, 아밀로오스함량, 지방산함량, 명도, a-value, b-value, 채도, 색상 및 알카리붕괴도 등의 형질에 대한 유전력 검정의 결과, 품질평가치의 유전력은 87.89％로 가장 높은 유전력을 나타내었으며, 단백질함량 ＞ 알카리붕괴도 ＞ 지방산함량 ＞ 아밀로오스함량 ＞ 색상 ＞ 명도 ＞ a-value ＞ b-value의 순으로 나타났으며, 채도의 유전력은 30.62％로 가장 낮음을 알 수 있었다.