• 한국작물학회지
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• 제52권1호
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• pp.112-121
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• 2007

Grain filling is a crucial factor that determines grain yield in crops since it is the final process directly associated with crops' yield performance. Grain filling process can be characterized by the interaction of rate and duration of grain filling. This study was conducted, using 16 temperate japonica rice genotypes, with aims to (1) seek variations in grain filling duration and rate on area basis, (2) compare the contribution of grain filling duration and rate to grain yield, and (3) examine the influence of temperature and solar radiation for effective grain filling on grain yield in relation to grain filling duration and rate. Grain filling rate and duration exhibited highly significant variations in the ranges of $20.7{\sim}46.3\;g\;m^{-2}d^{-1}\;and\;11.2{\sim}35.5$ days, respectively, depending on rice genotypes. Grain yield on unit area basis was associated positively with grain filling duration but negatively with grain filling rate. Grain filling rate and duration were negatively correlated with each other. Final grain weight increased linearly with the rise in both cumulative mean temperature and cumulative solar radiation for effective grain filling. Higher cumulative mean temperature and cumulative solar radiation for effective grain filling were the results of longer grain filling duration, but not necessarily higher daily mean temperature and daily solar radiation for effective grain filling. Grain filling rate demonstrated an increasing tendency with the rise in daily mean temperature for effective grain filling but their relationship was not obviously clear. It was concluded that grain filling duration, which influenced cumulative mean temperature and cumulative solar radiation for effective grain filling, was the main factor that determined grain yield on unit area basis in temperate Japonica rice.

• 한국작물학회지
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• 제32권1호
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• pp.103-111
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• 1987

Understanding grain filling characteristics represented by grain filling duration and grain filling rate is import-ant in improving higher yielding varieties and developing better cultural methods of rice (Oryza sativa L.). Recently developed 6 Japonica and 6 Japonica/Indica varieties were grown under 3 nitrogen levels at Experimental Farm of Chungbuk National University in 1986. The range of grain filling duration of 12 varieties was 20.9-39.0 days, while grain filling rate ranged from 53.8 to 136.6 mg. panicle$^{-1}$. day$^{-1}$. Although the difference of the average grain filling duration between Japonica varieties and Japonica/Indica was less than 4 days, the average grain filling rate of Japonica/lndica varieties was greater than Japonica more than 30%. Samgangbyeo showed the shortest grain filling duration of 21.0-24.2 days and the greatest grain filling rate of 119.3-143.8 mgㆍpanicle$^{-1}$. day$^{-1}$ under 3 nitrogen levels, while Seomjinbyeo and Milyang 23 showed the quite opposite grain filling characteristics. Nitrogen levels did not show any significant effects on grain filling characteristics. Negative correlation was round between grain filling duration and grain filling rate, and significant positive correlations of grain filling rate with grains/panicle, grain weight and panicle weight indicated that grain filling rate is more important characteristics of grain filling. Pathway analysis revealed that contribution of grain filling rate to panicle weight is rather indirect through grain weight.

• 한국작물학회지
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• 제63권2호
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• pp.120-130
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• 2018

Improvement in rice grain yield has been approached by means of genetic amendment, cultural management, and environmental adaptation. Subjecting the plant during the grain filling period to an appropriate environment plays a key role in achieving a high grain yield in temperate rice. Field experiments were conducted for two consecutive years with two planting times to assess the relations among grain filling traits, loss of leaf activity during the ripening period, and the grain yield of temperate japonica rice with wide environmental variation. Higher grain yields were attained in 2017 than in 2016 and with late planting than with early planting. The high grain yield accompanied a comparatively lesser increase in grain weight at the early filling stage but more gain in grain weight occurred during the late filling stage. Final grain weight correlated positively with grain filling duration but negatively with grain filling rate. Extended grain filling duration was associated with higher cumulative temperature and cumulative solar radiation for an effective grain filling period. The reduction in SPAD value ${\times}$ leaf dry weight from heading to harvest significantly correlated with final grain dry weight in a positive manner. No significant relation was found between grain filling duration and the decrease in SPAD value ${\times}$ leaf dry weight during the grain filling period. The results suggest that grain filling duration and loss of leaf activity during ripening independently contribute to environmentally induced yield improvement in temperate japonica rice.

• 한국작물학회지
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• 제33권1호
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• pp.5-11
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• 1988

Varietal differences of grain filling duration and rate are generally recognized in rice (Oryza sativa L.). But the differences of grain filling characteristics between the parts within a panicle might be present since it takes 6-8 days to finish anthesis in a panicle. To elucidate this, 6 Japonica and 6 Japonica/Indica varieties were grown under three nitrogen levels at the Experimental Farm of Chungbuk National University in 1986, and grain filling characteristics of top, middle and bottom parts of a panicle were analyzed. Rice grain filling duration could be divided into 3 phases, i.e., Lag phase(LP) of 5 days after heading. Linear increasing period (LIP) of 5-20 days after heading and Late filling period (LFP) thereafter. Grain weight difference between the panicle parts was greater during LIP in all the varieties and was decreased during LFP. The difference was greater in Japonica/Indica varieties. Samgangbyeo and Seomjinbyeo had the shortest and the longest grain filling durations with 22.6 and 37.1 days, respectively. In average, grain filling duration of the bottom part of a panicle was 1-2 days shorter than that of top or middle part. The differences were negligible in Daecheongbyeo, Taebaegbyeo and Milyang 23, while it was greater in Tongil with 4.9 days. Grain filling rates were ranged from 0.612 to 1.097 mgㆍgrain$^{-1}$ㆍday$^{-1}$ㆍMilyang 23 showed the lowest rate with 0.612-0.682 mgㆍgrain$^{-1}$ㆍday$^{-1}$, while the rates of Baegyangbyeo, Yongmoonbyeo, Samgangbyeo, Nongbaeg and Daeseongbyeo were about 1 mgㆍgrain$^{-1}$ㆍday$^{-1}$ㆍGrain filling rate of bottom part of a panicle was lower than that of top or middle part. The difference was samll in Nongbaeg and Daeseongbyeo, while it was the greatest in Tongil with 0.222 mgㆍgrain$^{-1}$ㆍday$^{-1}$. Grain filling duration and rate were not afftected by nitrogen level, but varietal and spatial differences of grain filling characteristics were highly significant. However, the spatial difference of grain filling rates within a variety was not significant. Grain filling characteristics of each part of a panicle were significantly correlated (r=0.7207-0.9879) with those of a whole panicle.

• 한국작물학회지
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• 제30권2호
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• pp.131-139
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• 1985

이모작재배에 적합한 극조숙 양질 다수성 소맥품종육성을 위하여 등수기간에 관여하는 유전자 작용에 대한 연구는 매우 중요하다. 추파성품종 Yam-hill과 Hyslop, 춘파성품종 Red Bobs와 Siete Cellos를 사용하여 4 $\times$ 4 complete diallel crosses F$_1$, F$_2$, BC$_1$ 및 BC$_2$를 작성, Jinks-Hay-man model를 이용하여 등숙기간에 관여하는 유전자 작용을 분석하였다. 본 시험은 오레곤 주립대학교에서 실시되었다. 그 결과의 개요는 다음과 같다. 전등숙기간인 출수에서 생리적 성숙기까지의 기간과 출수에서 개화까지의 기간에서 maternal effect 가 인정되지 않았으며 비대립유전자간 상호작용도 발현되지 않았다. 개화에서 생리적 성숙기까지의 기간에서는 비대립유전자간에 상호작용이 인정되었다. 춘파성 품종인 Red Bobs와 Siete Cellos는 전등숙기간과 출수에서 개화까지의 기간을 지배하는 우성유전자들을 가지고 있었으며 짧은 쪽에 비하여 긴쪽이 우성으로 발현되고 있었다. 대조적으로 추파성 품종인 Yamhill 과 Hyslop은 개화에서 생리적 성숙기까지의 기간을 지배하는 우성유전자들을 가지고 있었으며 긴쪽이 우성으로 작용하고 있었다. 그리고 이 유전자들은 문배친들간에 독립적으로 분포되어 있었다.

• 한국작물학회지
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• 제48권5호
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• pp.397-401
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• 2003

This experiment was conducted to know the characteristics of kernel growth as affected by various temperature regimes during grain filling using the varieties Hwaseongbyeo, Ilpumbyeo and Chucheongbyeo. The rice plants tested were grown in the natural condition at 1/5000a Wagner pots until flowering. After flowering, the rice plants were moved to controlled temperature conditions in a phytotron. The minimum/maximum daily temperature in the phytotron was controlled by 12/18, 15/21, 18/24, 21/27, and 24/$30^{\circ}C$, respectively. The grain weights were measured every three days after treatment. The mean daily kernel growth rate during active grain filling period showed different responses among varieties under various temperature regimes. The kernel growth rate of Chucheongbyeo was seriously reduced as temperature regimes were decreased. However, that of Ilpumbyeo was not influenced so critically. Ilpumbyeo showed some advantages in grain filling under low temperature regimes compared to Chucheongbyeo. The lag phase in grain filling of Chucheongbyeo was the longest among tested varieties, followed by Hwaseongbyeo under daily mean temperature regime of $15^{\circ}C$. Kernel weight of Ilpumbyeo increased fast in early grain filling phase under low temperature. This characteristic may be favorable for grain filling in temperate zone where the daily mean temperature is drastically dropped during grain filling period. Regression analysis with kernel growth rate and temperature showed the estimated critical low temperature for grain filling among varieties were $9^{\circ}C$, $12^{\circ}C$, $13^{\circ}C$ in Ilpumbyeo, Hwaseongbyeo and Chucheongbyeo, respectively. Under moderate temperature the duration of grain filling of Ilpumbyeo was longer than that of Chucheongbyeo. However, Under low temperature that of Ilpumbyeo was more favorable than Chucheongbyeo.

• 한국작물학회지
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• 제42권5호
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• pp.626-631
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• 1997

옥수수의 숙기가 서로다른 8개의 자식계통과 이들간의 이면교배에 의하여 생산된 28개 $F_1$을 공시하여 등숙기간의 유전분석을 실시하였던 바 그 결과는 다음과 같다. 1. 초기등숙기간에서는 상가적 효과가 큰 부분우성으로 추정되었으며 유효등숙기간은 비대립 유전자의 상호작용이 없는 초우성으로 추정되었다. 2. 총등숙기간과 흑색층 출현일수는 상가적 효과가 비상가적 효과보다 큰 부분우성으로 추정되었다. 3. 유전자 분포상태는 유효등숙기간과 총등숙기간에서 양친들 중 FR25는 열성유전자의 관여도가 크게 나타났으며 YUBC208은 열성유전자로서의 관여도가 크게 작용하였다. 4. 유효등숙기간과 총등숙기간에 관여하는 유효 유전자수는 최소한 5개 정도가 있는 것으로 추정되었다.

• 한국작물학회지
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• 제36권2호
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• pp.166-173
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• 1991

출수후 등숙기간 동안에 엽신의 노화속도와 동화산물의 전류특성과의 관계를 구명하며 등숙향상 및 단기등숙 품종육성을 위한 선발지표를 제공코자 엽신의 노화정도가 다른 올보리외 29품종 및 계통을 공시하여 엽신 노화율, 등숙율 및 상호 상관관계를 조사하였던 바 결과를 요약하면 다음과 같다. 1. 엽신의 노화속도 및 입충전속도(등숙율)는 계통에 따라 큰 차이가 있었다 2. 등숙초ㆍ중기(출수후 10-20일) 및 등숙중ㆍ후기(출수후 20-30일)의 엽신 노화율과 해당 각 시기의 등숙율과는 높은 정의 상관관계가 있었다. 3. 등숙초ㆍ중기의 엽신 노화율과 등숙전기간(출수후 10-35일)의 등숙율과는 부의 상관이 등숙중ㆍ후기의 엽신 노화율과는 고도의 정의 상관관계가 있었다. 4. 입중과 등숙중ㆍ후기 및 등숙전기간의 등숙율과는 고도의 정의 상관관계가 있었으나 등숙초ㆍ중기의 등숙율 및 등숙일수와는 상관이 없었다. 5. 노화지수의 감소 양상은 계통에 따라 4가지 유형으로 분류할 수 있었는데 종실수량 및 등숙율면에서 가장 이상적인 유형은 IV형이었다 6. 본 시험결과 단기등숙형 대맥 품종으로 가장 이상적인 형은 등숙초ㆍ중기에는 노화지수가 높으면서도 노화속도가 느리나 등숙중ㆍ후기에는 노화속도가 빠른 품종임이 구명되었다.

• 한국작물학회지
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• 제65권4호
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• pp.294-302
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• 2020

등숙기간 동안의 온도에 따라서 동일한 출수 후 일수가 경과하더라도 출수 후 적산온도가 달라져 종실의 등숙단계가 달라지기 때문에 수발아에 영향을 줄 수 있는 종실의 특성이 달라지게 된다. 그렇기 때문에 수발아 검정을 위한 처리 시점은 출수 후 일수가 아닌 출수 후 특정 적산온도에 조건을 맞춰 시험을 진행해야 한다. 한편 수발아 발생은 등숙기간 동안의 온도에 따라서 크게 달라진다. 이에 따라서 발생하는 전분립의 구조, 전분함량 및 ABA함량의 변이 등은 수발아 발생에 영향을 줄 것으로 생각되며, 특히 고온등숙 시 수발아 발생율의 증가와 종실 전분립의 구조, 유리당 함량 등 종실 이화학적 특성 변이와의 관계에 대한 추가적인 검토가 필요할 것으로 생각된다. 또한 고온등숙시 수발아 발생율이 증가하기 때문에 등숙기 고온에 노출되지 않도록 이앙시기를 조절하여 수발아 발생위험을 감소시켜야 한다.

• 한국작물학회지
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• 제30권1호
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• pp.39-46
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• 1985

추파 대·소맥의 조숙품종의 조기출수에 따른 개화등숙 및 수량성 변화를 구명하고자 대맥품종 조강보리, 밀양6호, 올보리, 동보리 1호 및 부농과 소맥품종 수원210호, 올밀, 조광 및 농림16호 등을 공시포장조건에서 파종기 차이와 장일처리로써 조기출수 및 출수기 차이를 유도하여 본 실험을 수행하여 얻은 결과를 요약하면 다음과 같다. 1. 파종기 및 장일처리에 의해 대·소맥에서 15일 출수기 차이가 유도되었으나, 성숙기는 불과 2∼6밖에 촉진되지 않았다. 2. 조기출수한 경우 출수∼개화 일수 및 등숙일수가 연장되었으며, 출수∼개화 일수 연장이 더 큰 것으로 나타났고, 이들 기간과 평균기온 간에는 각각 고도의 부상관이 있었다. 3. 조기출수만 것일수록 등숙초기의 엽면적은 좁았고, 엽면적유지기간(Leaf area duration)은 컸으며, 순동화율(NAR)은 낮았다. 4. 조기출수한 것에서 천립중은 증가하였으나 종실수량은 현저히 감소하였는데 이는 주로 수수 및 일수입수의 감소에 기인하는 것으로 나타났다.