• 한국농림기상학회지
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• 제3권1호
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• pp.55-70
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• 2001

It was unusual crop weather for 1998 and 1999 compared with normal in Korea. The consecutive days of the optimum ripening period for rice plant that had daily mean temperature 21~23$^{\circ}C$ for 40 days after flowering, increased with long anomalies in 1998~99. The air temperature during ripening period was much higher than the optimum temperature and lower sunshine hour than norm in the local adaptability tests of newly developed rice lines during those years. In response of rice cultivation to warming and cloudy weather during crop season, the yield shall be decreased. Most scientists agree that the rate of heating is accelerating and temperature change could become increasingly disruptive. Weather patterns should also become more erratic. Agrometeorologists could be analyzed yearly variations of temperature, sunshine hour and rainfall pattern focused on transient agroclimate change for last a decade. Rice agronomists could be established taking advantage of real time agricultural meteorology information system for fertilization, irrigation, pest control and harvest. Also they could be analyzed the characteristics of flowering response of the recommended and newly bred rice cultivars for suitable cropping plan such as cultural patterns and sowing or transplanting date. Rice breeders should be deeply considered introducing the characteristics of basic vegetative type of flowering response like Togil rices as prospective rice cultivars corresponding to global warming because of the rices needed higher temperature at ripening stage than japonica rices, photoperiod-sensitive and thermo-sensitive ecotypes.

• 원예과학기술지
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• 제32권1호
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• pp.1-9
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• 2014

This study investigated the effects of temperature on the shoot growth and flowering of potted kumquat [Fortunella margarita ( Lour.) Swingle] trees grown in subtropical conditions of I-Lan County in Taiwan. Temperature treatments included T 25-32, T 17-25, T 22, and T 18. The T 25-32 treatment trees were to the day/night temperatures of $25/18^{\circ}C$ for 2 weeks, followed by 28 weeks at $32/25^{\circ}C$. T 17-25 was exposed for 4 weeks to $17/10^{\circ}C$ followed by 26 weeks at $25/18^{\circ}C$. T 22 and T 18 were exposed at $22/18^{\circ}C$ and $18/13^{\circ}C$, respectively, for the entire duration of the experiment. Control trees were placed in a plastic greenhouse under conditions similar to the natural environment. The kumquat trees exposed to high-temperature environment of $32/25^{\circ}C$ showed more frequent and speedy sprouting of new buds, but induced the earlier termination of shoot elongation growth, resulting in decreased vegetative growth. The temperature treatments lower than $22^{\circ}C$ suppressed the new shoot production but increased the shoot growth period, resulting in increased shoot length and diameter. Temperatures higher than $25/18^{\circ}C$ readily induced flowering, with flowering being advanced under the higher temperature conditions such as $32/25^{\circ}C$. However, flowering was substantially inhibited under temperature conditions lower than $22/18^{\circ}C$, indicating the negative role of relatively lower temperatures on flowering of kumquat trees.

• The Korean Journal of Ecology
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• 제21권5_1호
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• pp.457.2-486
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• 1998

Ecological success of introduced species is frequently attributed to the reproductive characters of those species. We examined the relationship between both flowering season and plant size and reproductive characters in two introduced species of Taraxacum, e.g., T. officinale and T.laevigatum. Seventy six plants of T. officinale and 23 plants of T. laevigatum were randomly tagged from a population at the sungshin Women's University in April of 1997. The size and number of vegetative characters such as rosette diameter, leaf number, and the largest leaf length and width were measured for each plant at the onset of flowering. The infructescence was collected continually from each plant before seed dispersal from April to August of 1997. The number of infructescence per plant, and seed number and total seed weight per infructescence were measured. Mean individual seed weight per infructescence was also obtained. T. officinale possessed larger sized, but smaller number of, leaves than T. laevigatum, thereby resulting in no significant difference in total leaf area. There was a trend that vegetatively larger plants in both of these species produced reproductive characters larger in size or greater in number, except for seed number and total seed weight per infructescence in T. laevigatum. All reproductive characters examined in T. officinale decreased toward the end of flowering season. In T. laevigatum, infructescence number per plant also declined during a flowering season: however, mean seed number per infructescence increaed toward the end of flowering season with no significant seasonal change in the total seed weight per infructescence. T. officinale produced on average about twice as many seeds per plant as T. laevigatum during a growing season. These two Taraxacum species produced quite small seeds in size compared to the endemic species, exhibiting a far better dispersal ability of introduced species. These data demonstrate that most reproductive characters decline in size and number in both species during a long flowering period, but the two species appear to employ different strategies to achieve reproductive success in disturbed habitats.

• 한국작물학회지
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• 제65권3호
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• pp.241-247
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• 2020

온도와 일장처리를 달리하여 참깨 개화, 생육특성 및 수량성에 미치는 영향을 구명하고자 2019~2020년 2년에 걸쳐 수행하였으며, 그 결과를 요약하면 다음과 같다. 1. 단일조건(12시간)에서 온도 증가에 따른 참깨 품종의 개화일수 단축정도는 90일깨가 11일, 풍성깨가 10.5일, 아름깨가 10일이었으며 고온조건(28℃)에서 일장이 길어 질수록 참깨품종의 개화지연일수는 90일깨가 7.5일, 안산깨와 양백깨가 각각 9일, 풍성깨가 14.5일, 성분깨가 15일, 아름깨가 18일로 나타났다. 2. 개화일수와 경장, 주당삭수, 천립중, 10a당 수량간에는 부의 상관관계를 나타내었는데 개화소요 일수가 길어 개화가 늦어지면 생식생장기간이 줄어들고 수량관련 형질들의 기본특성을 확보할 수 있는 기간이 부족해진다. 3. 일장과 온도에 따른 품종 간 수량성 변화를 보면 안산깨, 아름깨는 온도가 높아질수록 수량이 감소하였으나 양백깨, DT45는 증가하는 경향을 나타내었다. 일장이 길어질수록 수량은 감소하는 경향을 나타났으며 참깨 품종간 반응을 다양하게 나타났다. 4. 풍성깨, 성분깨는 파종기를 앞당겨서 조기파종에 적합하였으며 DT45, 풍성깨, 90일깨, 안산깨, 성분깨는 파종기를 늦추어 만파를 할 경우 적합하였다. 양백깨와 아름깨는 5월 상순부터 중순까지 파종을 하였을 경우 수량성 확보에 유리하였다.

• 한국농림기상학회지
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• 제8권2호
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• pp.68-76
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• 2006

A thermal time-based two-step phenological model was used to project flowering dates of Japanese cherry in South Korea from 1941 to 2100. The model consists of two sequential periods: the rest period described by chilling requirement and the forcing period described by heating requirement. Daily maximum and minimum temperature are used to calculate daily chill units until a pre-determined chilling requirement for rest release is met. After the projected rest release date, daily heat units (growing degree days) are accumulated until a pre-determined heating requirement for flowering is achieved. Model calculations using daily temperature data at 18 synoptic stations during 1955-2004 were compared with the observed blooming dates and resulted in 3.9 days mean absolute error, 5.1 days root mean squared error, and a correlation coefficient of 0.86. Considering that the phonology observation has never been fully standardized in Korea, this result seems reasonable. Gridded data sets of daily maximum and minimum temperature with a 270 m grid spacing were prepared for the climatological years 1941-1970 and 1971-2000 from observations at 56 synoptic stations by using a spatial interpolation scheme for correcting urban heat island effect as well as elevation effect. A 25km-resolution temperature data set covering the Korean Peninsula, prepared by the Meteorological Research Institute of Korea Meteorological Administration under the condition of Inter-governmental Panel on Climate Change-Special Report on Emission Scenarios A2, was converted to 270 m gridded data for the climatological years 2011-2040, 2041-2070 and 2071-2100. The model was run by the gridded daily maximum and minimum temperature data sets, each representing a climatological normal year for 1941-1970, 1971-2000, 2011-2040, 2041-2070, and 2071-2100. According to the model calculation, the spatially averaged flowering date for the 1971-2000 normal is shorter than that for 1941-1970 by 5.2 days. Compared with the current normal (1971-2000), flowering of Japanese cherry is expected to be earlier by 9, 21, and 29 days in the future normal years 2011-2040, 2041-2070, and 2071-2100, respectively. Southern coastal areas might experience springs with incomplete or even no Japanese cherry flowering caused by insufficient chilling for breaking bud dormancy.

• 한국작물학회지
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• 제29권1호
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• pp.76-83
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• 1984

참깨의 개화습성은 분지, 과성, 실방수 등 식물학적외부 특성차이에 의하여 8가지의 초형으으로 나누어 조사한 결과를 요약하면 다음과 같다. 1. 참깨의 개화순서는 단경종이나 분지종 공히 상위부까지는 1절당 1일간격으로 개화되었으나 최상위절에서는 3∼8일이나 중단되었다가 다시 피는 개화일시정지현상을 보였는데 이러한 일시 개화정지현상은 참깨 후기등숙불량의 중요한 원인으로 추정되었다. 2. 단경종 3과성은 주화보다 측화는 4∼5절 하위절에서 개화시작되고 분지종 3과성은 주경에서 주화보다 측화는 3절 하위절에서 개화시작되었으며 분지에서는 주경주화가 5절위개화시 분지착화 1절에서 개화가 시작되었다. 3. 착화하위부에서는 같은 날에 측화는 주화보다 5절하위에서 피지만 그 거리는 상위부로 갈부록 좁혀들어 착화상위부에서는 측화는 주화보다 1절하위에서 피었다. 4. 착화중위부(7절∼9절)에서는 같은 날 한마디에서 1과성에서는 1개의 꽃이 개화되는 것이 정상이나 2개의 꽃이 개화되며(2과성), 3과성(3화성)에서는 4과성(4화성) 심지어는 5과성(5화성)으로까지 발현되는 현상을 보였다. 5. 분지종에서는 분기총화수가 전체화수의 BTQ형의 44％를 제외하고는 모두 67％∼75％를 보여 분지종에서 분지화수가 전체화수에서 차지하는 비중이 높았으며 고위분지일수록 개화기간이 길어지고 화수가 많아지는 현상을 보였다. 6. 분지종 3과성 2실 4방(BTB형)은 주경과 분지에서 공히 3과성으로 개화되고 개화기간도 같은데 반해, 분지종 3과성 4실 8방(BTQ형)은 주경만이 3과성으로 개화되었을 뿐 분지는 1 과성으로 개화되었고 개화중기까지 만 분지에서 개화되고 개화후기에는 주경만이 개화되었다. 7. 분지종은 평균 128개가 개화되었고 단경종은 72개가 개화되어 화수는 분지종이 많았고 개화소요일수는 단경종이 34일인데 비해 분지종은 24일로서 단경종보다 10일이 빨라서 분지종이 화수는 많고 개화기간은 짧은 경향을 보였다. 8. 단경종보다는 분지종의 개화수가 현저히 많고 분지종중에서도 3과성2실4방이 가장 많아 NMB<NMQ<NTQ<BMQ<NTB<BMB<BTQ<BTB의 경향이 뚜렷하였다. 9. 참깨의 꽃을 엽액에 착생되기 때문에 참깨의 꽃과 잎의 착생위치는 일치되며 BMB와 NTB형의 개화진행 습성은 역시계침, 나선형으로 개화가 진행되는 십자나선형화서, 십자나선형엽서를 보였다.

• 한국농림기상학회지
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• 제18권3호
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• pp.162-169
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• 2016

기준기상위험이란 한 지역의 평년기후조건이 작물재배에 미칠 수 있는 '농업기상학적 피해가능성'으로서, 동일 작물 재배 시 지역에 따른 재해위험을 비교하는 기준이 된다. 지구온난화로 인하여 겨울 온도는 상승할 것으로 예상되지만, 기상이변의 빈도 또한 늘어날 것으로 전망되기 때문에 미래 기후조건에서 과수의 동해, 상해 등 저온에 의한 재해위험이 주목 받고 있다. 그러나 기후의 변화는 과수 생물계절도 변화시키므로 기상조건에 근거한 단순한 재해위험 전망은 기후변화적응의 실용측면에서 별 도움이 되지 못한다. 본 연구에서는 전국 주요 지역의 과거 및 기후변화시나리오를 이용하여 배, 복숭아, 사과의 생물계절을 예측하고 생육단계별 기온과의 상호작용에 근거하여 저온 유래 기준기상위험을 계산함으로써 미래의 재해가능성을 전망하였다. 휴면해제일은 미래로 갈수록 늦어질 것으로 전망되었으며, 발아일과 개화일의 경우 빨라질 것으로 예상되었다. 대구, 전주, 목포의 경우 휴면해제일의 지연 정도가 미래로 갈수록 커졌으며 발아일과 개화일의 경우 서울, 인천 지역이 다른 지역에 비해 늦게 나타났다. 서울과 인천, 대구와 전주, 부산과 목포가 서로 비슷한 양상을 나타내었다. 휴면기 동안에는 전 지역이 동해에 안전하였으나 휴면해제-발아기 동안에는 전 지역이 동해에 취약하였고, 발아기-개화기의 위험은 미래로 갈수록 대체로 낮아졌지만 지역에 따라 위험이 커지는 곳도 있었다.

• 아시안잔디학회지
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• 제8권2호
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• pp.65-85
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• 1994

This study was carried out to develope DBMS program and use CAD for flower, leaf and fruit characteristics of deciduous woody landscape plants in Suwon, Korea from January 1, 1992 to March 20,1993. The results were as follows : 1. The flower, leaf and fruit characteristics of 211 species which were anthesis, flowering period, flower color, leaf spreading, leaf color before fall leaf coloring, fall leaf color, fruiting, fruit period, fruit color and trunk color were investigated through field survey. 2. DBMS program for flower, leaf, fruit and trunk characteristics of deciduous woody landscape plants was developed with data through field survey. And the DBMS program might contribute to the decision of appropriate times for planting design for flowers, fall foliage color, fruit color and hark color. 3.During this procedure, CAD software was used to demonstrate the deblossom before leaf spreading and leaf spreading in flowering, fall foliage color, fruit color after leaf falling, and hark color for planting design as well as seasonal color change of deciduous woody landscape plants.

• Horticulture, Environment, and Biotechnology : HEB
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• 제59권6호
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• pp.827-833
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• 2018

Plasma lighting systems have been engineered to simulate sunlight. The objective of this study was to determine the effects of plasma lighting on tomato plant growth, photosynthetic characteristics, flowering rate, and physiological disorders. Tomato plants were grown in growth chambers at air temperatures of $25/23^{\circ}C$ (light/dark period), in a $16h\;day^{-1}$ light period provided by four different light sources: 1 kW and 700 W sulfur plasma lights (1 SPL and 0.7 SPL), 1 kW indium bromide plasma light, and 700 W high pressure sodium lamp (0.7 HPS) as a control. The totaldry weight and leaf area at 0.7 SPL were approximately 1.2 and 1.3 times greater, respectively, than that of 0.7 HPS at the 62 days after sowing (DAS). The maximum light assimilation rate was observed at 1 SPL at the 73 DAS. In addition, the light compensation and saturation points of the plants treated with plasma lighting were 98.5% higher compared with HPS. Those differences appeared to be related to more efficient light interception, provided by the SPL spectrum. The percentage of flowering at 0.7 SPL was 30.5%, which was higher than that at 0.7 HPS; however, there were some instances of severe blossom end rot. Results indicate that plasma lighting promotes tomato growth, flowering, and photosynthesis. Therefore, a plasma lighting system may be a valuable supplemental light source in a greenhouse or plant factory.

• 생약학회지
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• 제51권4호
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• pp.291-296
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• 2020

Filipendula glaberrima (FG) is a plant endemic to South Korea. It is economically important as a food source and used as a medicine in treating ailments. Filipendula flowers are characterized by the presence of several polyphenolic constituents. The aim of this study is to determine the content of (+)-catechin in Filipendula glaberrima collected from different regions at different flowering stages. High-performance liquid chromatography with a gradient elution system (0.5% acetic acid in water : acetonitrile = 95 : 5 to 0 : 100 for 35 min) was used. A reverse-phase INNO column with UV detection at 278 nm was employed. The results revealed that F. glaberrima from Mt. Odae has the highest (+)-catechin content (10.600 mg/g). Furthermore, its content was the lowest in samples collected during the pre-flowering period and the highest at the early-flowering stage. This study provides a basis in establishing the optimal period and the best region for collecting F. glaberrima with maximized (+)-catechin yield.