• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.410-415
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• 1997

To investigate the flowering and pod setting characteristics of peanut, Dae-kwangtangkong and Shinnamkwangtangkong were planted on April 20 and May 10 in 1994 at National Honam Agricultural Experiment Station. Number of days from planting to the maximum flowering in Daekwangtangkong were shorter than those of Shinnamkwangtangkong by 6 days in April 20 planting and by 13 days in May 10 planting. Flowering durations of Daekwangtangkong and Shinnamkwangtangkong in April 10 planting were 73 and 71 days, respectively, while those of both varieties were 64 days in May 10 planting. The rates of matured pods on cotyledonary, primary or secondary, and third branches were 58∼78, 6∼15 and 0∼2％, respectively. The rates of effective flowers in Daekwantangkong and Shinnamkwangtangkong were 10％ and 8％, respectively, in April 20 planting. The rates of matured pods were 100％ in Daekwangtangkong and 97％ in Shinnamkwangtangkong when pods were set within 15 days after the initial flowering, while the rate was decreased markedly when pods were set later than 35 days after the initial flowering.

• Journal of Plant Biotechnology
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• v.44 no.4
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• pp.438-447
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• 2017

Flowering is one of the most important development traits related to the production of Brassica rapa crops. After planting, a sudden low temperature triggers premature flowering, which leads to a reduction in the yield and quality of harvested production. Therefore, understanding the mechanism of flowering control is important in the agricultural productivity for preventing Brassica rapa crops. Vernalization is generally known as the main factor of flowering in the Brassica plant. However, in the subspecies of Brassica rapa, some accession such as Yellow sarson and Komatsuna display the flowering phenotype without vernalization. Circadian genes, which diurnally regulate plant physiology, have a role for photoperiodic flowering but are related to the regulation of the vernalizarion mechanism. In this report, the 22 B. rapa accession were divided into two groups, vernalization and non-vernalization, and the sequenced circadian gene, BrPRR1s. Among them, the BrPRR1b gene was found to have deletion regions, which could classify the two groups. The PCR primer was designed to amplify a short band of 422bp in the vernalization type and a long band of 451bp in the non-vernalization type. This primer set was applied to distinguish the flowering types in the 43 B. rapa accession and 4 Brassica genus crop, Broccoli, cabbage, mustard, and rape. The PCR analysis results and flowering time information of each crop demonstrated that the primer set can be used as marker to discern the flowering type in Brassica crops. This marker system can be applied to the B. rapa breeding when selecting the flowering character of new progenies or introducing varieties at an early stage. In addition, these results displayed that the circadian clock genes can be a good strategy for the flowering control of B. rapa crops.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.1
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• pp.42-54
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• 2016

It is highly anticipated that warming temperature resulting from global climate change will affect the phenological pattern of kiwifruit, which has been commercially grown in Korea since the early 1980s. Here, we present the potential impacts of climate change on the variations of flowering day of a gold kiwifruit cultivar, Haegeum, in the Jeonnam Province, Korea. By running six global climate models (GCM), the results from this study emphasize the uncertainty in climate change scenarios. To predict the flowering day of kiwifruit, we obtained three parameters of the 'Chill-day' model for the simulation of Haegeum: $6.3^{\circ}C$ for the base temperature (Tb), 102.5 for chill requirement (Rc), and 575 for heat requirement (Rh). Two separate validations of the resulting 'Chill-day' model were conducted. First, direct comparisons were made between the observed flowering days collected from 25 kiwifruit orchards for two years (2014-15) and the simulated flowering days from the 'Chill-day' model using weather data from four weather stations near the 25 orchards. The estimation error between the observed and simulated flowering days was 5.2 days. Second, the model was simulated using temperature data extracted, for the 25 orchards, from a high-resolution digital temperature map, resulting in the error of 3.4 days. Using the RCP 4.5 and 8.5 climate change scenarios from six GCMs for the period of 2021-40, the future flowering days were simulated with the 'Chill-day' model. The predicted flowering days of Haegeum in Jeonnam were advanced more than 10 days compared to the present ones from multi-model ensemble, while some individual models resulted in quite different magnitudes of impacts, indicating the multi-model ensemble accounts for uncertainty better than individual climate models. In addition, the current flowering period of Haegeum in Jeonnam Province was predicted to expand northward, reaching over Jeonbuk and Chungnam Provinces. This preliminary result will provide a basis for the local impact assessment of climate change as more phenology models are developed for other fruit trees.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.230-236
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• 2022

This study was carried out to produce two-flowered seedlings, harvest them early in a greenhouse, and extend the harvest period. This study was carried out to effectively produce the second truss blooming seedlings to harvest tomatoes early and extend the harvest period. For production of the second truss blooming seedlings (one stem), the nutrient solution EC was supplied at 1.5, 2.0, 2.5 dS·m^-1, and dynamic management (3.0 → 3.5 → 4.5 dS·m^-1). The seedling period was 60 days, which was 20-40 days longer than conventional seedlings, and 10 days longer than the first truss blooming seedlings (cube seedlings). The plant height was 78 and 77 cm in EC 2.5 dS·m^-1 and dynamic management respectively, which was shorter than EC 1.5 dS·m^-1 with 88 cm. As for the EC in the cube before formulation, dynamic management had the highest EC 5.5 dS·m^-1, and the cube supplied with EC 1.5 dS·m^-1 had the lowest. The production yield by treatment did not a difference among in the second truss blooming seedlings, but the first truss blooming seedlings showed lower productivity than second truss blooming seedlings. The second truss blooming seedling were harvested 35 days after planting on June 4, the first harvest date, and the first truss blooming were harvested in 42 days on June 11th. There was no difference in plant height and root growth due to bending at frequency planting. In the study on the production of the second truss blooming seedlings (two stem), the nutrient solution EC was supplied under 2.0, 2.5, 3.0 dS·m^-1, and dynamic management (3.0 → 3.5 → 4.5 dS·m^-1). The seedling period was 90 days, which was 40-50 days longer than conventional seedlings and 10 days longer than the first truss blooming seedlings (cube seedlings). Plant height was 80 and 81 cm in EC 2.0 dS·m^-1 and 2.5 dS·m^-1 respectively, but was the shortest at 73 cm in dynamic management. EC in the medium increased as the seeding period increased in all treatments. The dynamic management was the highest with EC 5.1 dS·m^-1. There was no difference in yield among EC treatments in the second truss blooming seedlings, which had a longer seeding period of about 10 days, produced 15% more than the first truss blooming seedlings. In order to shorten the plant height of the second truss blooming seedlings, it is judged that the most efficient method is increasing the concentration of nutrient solution.

• Korean Journal of Plant Resources
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• v.14 no.2
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• pp.163-168
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• 2001

This study was conducted to obtain basic information on cross breeding for developing bolting resistant variety of Angelica gigas NAKAI which has been subjected to severe yield reduction resulted from flower-stalk initiation during the growth. Compatibility of selfing and/or crossing pollination among 5 local cultivars were tested. Results obtained are summarized as follows. In case of three year old plant, all cultivars emerged March 14 and bolted from May 12 to May 13. Ponghwa cultivar was flowered 3 to 5 days earlier than other cultivars. Flower duration continued 41 to 43 days. Interval of flowering date from main stem to first primary branch, from first to second or second to third primary branch was 9 to 13 days. Emergency of stamen proceeded 4~8 days of pistil initiation demonstrating that Angelica gigas NAKAI is protandrous plant. Furthermore initiation of first pistil was 1~4days later than formation of last stamen in the same flower cluster. Percent pollination of Angelica gigas NAKAI was 52% under natural condition, so called open-pollination, but bagging by enveloping flowers was as low as 0.4~2.4%. In the result of compatibility test, all local cultivars tend to show both of self-and cross-compatibility. Inpollination, ‘Muju’$\times$‘Muju’combination showed highest fertility up to 40.8% whereases cross pollination, ‘Pyeongchang’$\times$‘Inje’combination, showed 67.0% fertility.

• FLOWER RESEARCH JOURNAL
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• v.17 no.1
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• pp.15-22
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• 2009

This study was conducted to examine characteristics of rhizome growth and flowering of white lotus (Nelumbo nucifera) plant in Muan Hoesan-lake for collecting the basic data on the cultivation and the flowering which is growing in Muan Hoesan-lake of Jeonnam province in Korea. We have planted from the seeds and the enlarged rhizomes of the white lotus which were planted in the plastic containers on April 20 and May 4, 2008, and cultivated under rain shelter condition. Rhizome growth pattern and the flowering characteristics of the white lotus were examined on September 4, 2008. Main rhizomes of the white lotus propagated by the seeds and the enlarged rhizomes were branched by 10% and 15%, respectively. Numbers of nodes in the bloomed and non-bloomed rhizomes of the white lotus were over 14 and below 11, respectively. Flower was not observed in the white lotus when propagated with seeds, however, flowers came out up to 80% by the enlarged rhizomes. First flowers were bloomed from the late July and to the early August, and the number of flowers were 4.0~4.4. The first flower stalks without branching of the main rhizome were emerged in 8.8th node, however, that with branching were 8.0th node. Time to flowering from the emergence of flower stalk on the above-ground parts were required 16 days. White flowers from the lotus were 15.3 cm in height and 28.2 cm in width, their longevity was 3.3 days and the averaged flower fresh weight was 29.2 g. The results conclude that optimum number of nodes on the main rhizomes for blooming the white lotus flowers should be over 8 nodes before the rhizome enlargement.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.1
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• pp.1-12
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• 2022

Tilia amurensis is an important honey plant. As T. amurensis mainly distributes mountainous area with various elevations in Korea, accurate prediction of blooming time at the different elevation would benefit forest beekeepers. In this study, we measured time-dependent blooming progress of T. amurensis in Mt. Gariwang area ranging from 500-1500m. Additionally we collected blooming data from web and published literatures and estimated the variation of blooming time relative to the geographic locations. Flowers began to bloom from July 6 to July 22 with full blooming on July 14 in location where elevation is 638m in Mt. G ariwang area in 2021. Based on these databases, a growing degree day (G DD) model was developed for prediction of T. amurensis blooming progress using average daily temperatures. Using the starting date of G DD accumulation of January 1 and base temperature of 5 ℃, blooming period ranging from 10% to 90% of cumulative blooming rate was estimated as 860-1198 degree days (DD). This corresponded to the beginning to the end of July in Mt. Gariwaning area in 2021. This model could explain the phenological variations of T. amurensis flower blooming possibly affected by elevation within geographic area, latitude or year relative to the climate change, and aid forest beekeepers for better timing of nectar foraging by honey bees.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.81-81
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• 2022

잇꽃(Carthamus tinctorius L.)은 국화과에 속하는 두해살이 초본 식물로 한자명은 홍화(紅花), 영명으로는 Safflower를 사용하고 있다. 우리나라의 잇꽃 재배는 2010년 39ha 수준이 재배되다가 2014년에는 76ha까지 확대되었으나, 점차 감소하는 추세를 보이고 있으며 2020년에는 52ha가 재배되고 있는 것으로 보고되었다. 잇꽃은 종자를 약용으로 이용하거나 꽃잎을 건조하여 천연 염색제 및 향신료로 이용하고 있으나, 일본 산형(山形)현에서는 잇꽃의 경관적 가치를 이용해 홍화 축제를 개최함으로써 소득작목으로 자리매김하고 있다. 본 연구는 지리산을 중심으로 한 준고랭지 지역에서 잇꽃의 경관적 가치의 활용 가능성을 검토하고자, 국립농업유전자원센터로부터 총포에 가시가 없는 무가시형 유전자원(IT323225, IT333473, IT333482)을 분양받아 가시가 있는 재배종과 파종시기별로 개화 특성 등을 비교하였다. 표고 500m 준고랭지의 비가림 하우스에서 3월 하순부터 6월 상순까지 파종시별로 출현율을 검토한 결과, IT 323225 자원은 관행의 3월 하순 파종에서도 40.5%의 낮은 출현율을 보였다. 3월 하순 파종에서 재배종은 6월 22일경에 개화기에 도달하였으나, 무가시형 유전자원들은 7월 2일~5일경에 개화기에 도달하여 만생종의 특성을 보였다. 파종시기를 늦춰 5월 하순에 피종하는 경우 무가시형 자원들은 7월 27일~29일경에 개화기에 도달하였으며, 개화기 전후의 개화 지속기간은 8~10일이 소요되어 3월 하순에 파종하여 7월 상순에 개화하는 경우보다 2~4일이 단축되는 경향이었다. IT333473 자원의 개화기 초장은 5월 하순 파종하는 경우 관행의 3월 하순 파종보다 43.6%가 즐어든 71.1cm를 보였고, 분지수는 41.6% 감소한 8.0개/주 수준을 보였다. 식물체당 착화수 또한 파종시기를 늦춤에 따라 감소하는 경향이었으나 화당 종자수는 IT323225 자원은 5월 중순과 하순 파종시에 증가하는 양상이었고 IT333473 자원과 IT333482 자원은 재배종과 같이 감소하였다. 하계 휴양지로 각광받고 있는 지리산권에서 무가시형 잇꽃 자원의 경관적 가치 활용 가능성을 검토한 결과, 파종시기를 5월 하순으로 늦추는 경우 성수기인 7월 하순과 8월 상순에 개화가 가능하였다. 또한 식물체의 초장이 71.1~83.6cm 수준으로 단축되어 경관 조성에 유리한 특성을 보였다.

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.147-155
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• 1991

Effects of harvest date, number of the leaves remained on stump after flower cutting, duration of cold treatment on the growth and flowering of L. elegans 'Connecticut King' bulb were tested. Shoot emerging rate increased over 90% by delayed cold treatment, late harvesting time and more leaves remained. Flowering rate increased over 90% when conducted cold treatment of 90 days to the premature bulb at flowering date, the bulb matured for 50 days with 10 leaves and the bulb matured for over 30 days with 20 leaves, and when conducted cold treatment of 50 days to the bulb matured for over 30 days with all leaves. Delayed cold treatment duration shortened days needed to shoot emergence and flowering. Especially days to flower of the premature bulb at flowering date were the shortest of all treatments, and can be flowered within 100 days after planting. In generally, plant height, number of flowers per plant and stem diameter generally increased by longer bulb maturing period after flower cuting, and the premature bulb harvested at flowering date showed poor growing and flowering responses. But, if used the larger size bulb, it is believed that the prematured bulb can be forced to flower normally in current year without bulb maturing period.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.1
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• pp.103-108
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• 1996

The changes in major characteristics of vegetable soybean at different stages were investigated. The 100-seed weight of vegetable soybean had a tendency to increase before 43 days after flowering, but decrease slightly after then. After 37 days after flowering, the sucrose content of Douya had a tendency to decline and in case of Shirofusa, total sugar content was sharply decreased at 40 days after flowering. The total vitamin C content of Douya and Shirofusa was dramatically increased at 37 days after flowering and then got the plateau, otherwise the total vitamin C content of Shirofumi and Hwaeomputkong was the highest level at 43 days after flowering. The hardness changes of vegetable soybeans were tend to increase according days after flowering. In sensory evaluation, preference score was significantly associated with harvesting stages. Correlation coefficient between sweetness and beany taste was significantly negative.