• 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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• 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.

• 한국초지조사료학회지
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• 제15권1호
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• pp.37-42
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• 1995

This experiment was canied out to study the effects of seeding and harvesting dates on the growth of early and late maturing rye(Seca1e cereale L.) varieties at the forage testing field of S.N.U., Suweon, from September 1986 to May 1989. Leaf and tiller numbers of rye per plant were increased with earlier seeding date, but no difference in the tiller numbers was found between harvesting dates of early and late maturing rye varieties. Tiller dry weight of an early maturing rye veriety, Wintermore was higher than that of a late maturing rye variety, Kodiak when sown as early as September. Maximun leaf area index(LA1) and leaf area index duration(LA1D) were achieved with earlier seeding and early maturing rye varieties. A higher correlation between the maximum LA1 or LAID and dry matter accumulation of rye varieties was observed in this experiment.

• 한국대기환경학회지
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• 제19권3호
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• pp.285-296
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• 2003

The measurement of the radiation energy, trunk temperature, leaf area index (LAI), air temperature, vapor pres-sure, and precipitation has been conducted under a mixed forest at Kwangneung Arboretum during the period of 2001. Characteristics of the diurnal and seasonal variation of the radiative energy were investigated. The aerodynamic roughness length was determined as about 1.6 m and the mean albedo was about 0.1 The downward short-wave radiation was linearly correlated with the net radiation and its correlation coefficient was about 0.96. From this linear relation, the heating coefficient was calculated and its annual mean value was about 0.21 The albedo and heating coefficient was varied with season, surface characteristics, and meteorological conditions. The diurnal and seasonal variations of radiation energy were discussed in terms of the surface characteristics and meteorological conditions. In the daytime, during clear skies, net radiation was dominated by the shortwave radiation. In presence of clouds and fog, the radiation energy was diminished. At night, the net radiation was entirely dominated due to the net longwave radiation. There was no distinct diurnal variation in net radiation flux during the overcast or rainy days. The net radiation was strongest in spring and weakest in winter. The seasonal development in leaf area was also reflected in a strong seasonal pattern of the radiation energy balance. The timing, duration, and maximum leaf area and trunk temperature were found to be an important control on radiation energy budget. The trunk temperature was either equal or warmer than air temperature during most of the growing season because the canopy could absorb a substantial amount of sunlight. After autumn (after the middle of October), the trunk temperature was consistently cooler than air temperature.

• 한국작물학회지
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• 제50권1호
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• pp.45-54
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• 2005

This study was carried out to investigate the patterns of dry matter (DM) production and accumulation, and to screen the relationships between related major growth characters and DM accumulation in four cassava varieties in Bogor $(6^{\circ}19'-6^{\circ}47'S,\;106^{\circ}21'-107^{\circ}13'E)$, West Java, Indonesia. Gading and Adiral developed an enough source and canopy in short at the early growth phase and then translocated assimilates to storage roots with a higher partitioning rate, even these varieties were considered as early-bulking varieties, which have superior source and sink potentials in increasing yield and DM of tubers. The root/shoot ratio (R/SR), total dry weight (TDW), leaf area duration, leaf area index (LAI), and number of tubers showed higher positive correlations with the dry weight of roots (DWR), and the direct effects of TDW, R/SR, and LAI on the DWR were higher. These characters were considered to be useful target characters to screen cassava varieties with high yield potential and high DM in aspect of tuber production.

• 한국응용곤충학회지
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• 제33권2호
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• pp.60-65
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• 1994

침엽수 계통의 많은 수종은 가해하는 솔잎벌(Nesodiprion japonicus{{{{( { M}_{ ARLATT}) }}}}) 생태중 생활사에 관하여 조사한 것을 요약하면 다음과 같다. 성충은 1년 2회 발생하였으며, 암컷과 수컷이 같은 색 (검정)이고, 암컷의 몸체는 수컷보다 굵고 크며 촉각은 빗살모양으로 수컷이 암컷보다 크다. 성충의 수명은 3~4일, 우화율은 92% 성비는 6(female): 4(male)로 나타났다. 성충은 침엽의 조직내에 1입씩 산란하며 산란된 배 입은 각색으로 변한다. 란 기간은 $14.3\pm$1.2일이었으며, 란의모양은 짧은 바나나형이고 등황색을 띠며 크기는 $2.4\pm$0.2mm 이다. 유충기간은 $30.3\pm$2.1일이고, 크기는 $20.1\pm$2.2mm이다. 두정에는 흑빈이 있고 몸체는 광택이 있는 녹생으로서 전후야란은 황색을 띠고 있다. 노숙유충이 되면 녹색이 연녹색으로 변하고 두정의 흑반도 없어진 후 1회 발생 때의 유충은 솔잎의 기부에 , 2회 대의 유충은 지피물 사이에 고치를 짓고 융화한다. 전용기는 $14.3\pm$2.0일이였고, 크기느 $10.1\pm$0.2mm이다. 용기간은 $12.2\pm$1.3일이었으며, 크기는 $10.1\pm$0.2mm이다.

• 한국식물병리학회지
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• 제10권2호
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• pp.78-82
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• 1994

Unusually severe rice blast epidemic sweeped over the rice growing area in Gyeongnam Province and elsewhere in 1993. Leaf blast infection was reached to 33,133 ha, which is about 24.5% of total paddy area and neck blast infection was apparent throughout 4,421 ha. Major factors affecting such an unusual epidemic appeared to be as follow: Firstly, low temperature, frequent rainfall and coincidentally insufficient duration of sunshine through July and August; Secondly, most cultivars possessing low levels of field resistance were cultivated in wide areas: Thirdly, blast fungus population was enough for successive infection under optimum weather condition and most races distributed in field were able to infect most cultivars.

• 한국작물학회지
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• 제50권5호
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• pp.309-318
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• 2005

Higher level of KCl application stimulated both leaf area index and leaf area duration in all cassava varieties, while the leaf and tuber number of the bitter varieties (high cyanide-level varieties) decreased in proportion to the level of KCl application. The root/shoot (R/S) ratio and harvest index (HI) were negatively related with the level of KCl application in all cassava varieties. The bitter varieties obtained the lowest R/S ratio at the level of 100 - 150 kg KCl $ha^{-1}$, while the sweet varieties (low cyanide-level varieties) acquired the highest values at the level of 50 - 150 kg KCl $ha^{-1}$. Also, the sweet varieties showed the lowest HI at the level of 250 kg KCl $ha^{-1}$, but the bitter varieties at the level of 150 kg KCl $ha^{-1}$. At 6 - 8 months after planting, the sweet varieties tended to obtain higher starch content of roots (tubers) at the level of 50 - 150 kg KCl $ha^{-1}$, while the bitter varieties at the level of 150 - 250 kg KCl $ha^{-1}$. Relatively lower level of 50 - 150 kg KCl $ha^{-1}$ was more appropriate for decreasing hydrocyanic acid (HCN) content of roots (tubers) in the sweet varieties at the harvest time, and the level of 250 kg KCl $ha^{-1}$ was adequate to decrease not only HCN content of leaves but also that of roots (tubers) in the bitter varieties during the growing period. To obtain higher yield and starch content of tubers, and lower HCN content of roots (tubers), it was recommended that the sweet varieties are applied with the level of 50 - 100 kg KCl $ha^{-1}$ and the bitter varieties with the level of 150 - 200 kg KCl $ha^{-1}$, respectively, in Latosol soils of Bogor areas, West Java.

• 현장농수산연구지
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• 제10권1호
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• pp.77-90
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• 2008

본 연구는 오이묘의 생육단계에 따라 저온처리 온도와 지속기간이 오이 생육, 과실특성 및 수량에 미치는 영향을 구명하고자 실시하였으며 주요 결과는 다음과 같다. 1. 10시간 저온처리(3℃ 및 0℃)하여 20일간 수경재배한 오이의 초장은 무처리 (20℃)에 비해 각각 25 및 30%, 엽면적은 34 및 37% 감소되었으나, 6℃ 처리에서는 무처리와 큰 차이가 없었다. 저온처리 기간에 따른 생육저해는 처리 시간에 비례하여 증가하는 경향이었다. 2. 저온처리(3℃, 10시간)횟수를 1, 2 및 3회로 증가할수록 초장, 엽면적 및 건물중은 무처리에 비해 크게 감소하였으나 1회와 2회 처리간에는 유의차가 없었고, 3회 연속처리에서만 현저히 감소하였다. 3. 오이과실의 개화 후 일수에 따른 신장속도는 무처리는 0.61~2.60cm/일 인데 비하여 0℃, 15시간의 저온 처리는 0.59~2.26cm/일로 약 10% 감소되었다. 4. 저온처리(0~3℃,10시간)는 오이의 상품과율을 25~26% 감소시켰고, 하품과율은 현저히 증가시켰다. 5. 오이 수량은 6℃, 10시간 처리에서는 무처리와 차이가 없었으나 3℃와 0℃처리는 무처리에 비해 20일묘에서 15~25%, 30일묘에서 22~37% 감수되었다. 0℃에서 5시간, 10시간 및 15시간 저온처리하였을 때에는, 무처리에 비해 각각 18%, 30%, 및 36% 감수되었다.

• 한국작물학회지
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• 제48권2호
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• pp.108-112
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• 2003

Foehn damage on rice plant is one of the important abiotic stresses in eastern costal area of Korea. To know the relationship between foehn impact and morphological traits of rice, wind tunnel method was used with 106 rice cultivars. Less influencing traits on foehn were short panicle, large panicle number per hill, thin panicle neck, and the flag leaf of narrow, short and thick. Leaf pubescence reduced the impact on foehn. 'Naepungbyeo' belong-ed to foehn tolerant varietal group, while 'Ansanbyeo' belonged to the opposite group. Three levels of root cutting treatment with two rice cultivars were conducted to evaluate the foehn impact using wind tunnel. The severity of wind damages was followed the sigmoidal curve duration of wind tunnel treatment were prolonged. Different responses of root cutting to wind tunnel treatment could be used to evaluate the severity of the foehn impact. 'Naepungbyeo' was one of the less implausible cultivars on foehn. 'Nae-pungbyeo' showed tolerant response to wind under 21% root removing treat-ment (20㎝ root cutting), however 'Ansanbyeo' was wilted under the same treatment. In case of 35 % root removing treatment(10㎝ root cutting), both rice cultivars failed to alive against foehn wind.