• Current Research on Agriculture and Life Sciences
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• v.31 no.1
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• pp.61-64
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• 2013

This study identified the effect of night time temperatures on the flowering period of spray-chrysanthemum during the summer season in South Korea. According to the results for 2005, the temperature at night time sustained more than $25^{\circ}C$ for 23.6 days during the short day period and delayed the flowering period for 22 days. Similar observations were reported in 2006, as the night time temperature sustained more than $25^{\circ}C$ for 23.6 days during the short day period and delayed flowering period for 23 days. The results for 2007 year showed that night time temperature sustained more than $25^{\circ}C$ for 31.9 days during the same period and delayed flowering for 31 days. In conclusion, based on the results for 2005 to 2007, a specific correlation was found between high night time temperatures and a delayed flowering period for the 'Euro' spray-chrysanthemum.

• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.170-177
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• 2007

The objectives of this study were to select early, late, and abundant flowering trees of black locust from domesticated and introduced cultivars, and prediction of flowering period by calculation of accumulated temperature in spring. Four cultivars (Debreceni-2, Pusztavacs, Jaszkiseri, and Rozsaszin AC) from Hungary and a cultivar from Beijing, China, were introduced, propagated by seed and planted in a seed orchard. For domesticated black locust, 63 cultivars from 10 locations throughout the country were selected and propagated by root cutting. Criteria for selection of domesticated cultivars were abundant flowering, long flowering period, or abundant nectar production with, if possible, straight stems. Accumulated temperature was calculated from data of a nearby weather station by accumulating daily maximum temperature minus 5 degree Celsius from January 1 up to the date reaching 880 degrees. Daily mean temperature was also used to calculate accumulated temperature up to the date reaching 450 degrees. The percentages of two-year and three-year-old flowering trees propagated by root cutting were higher than that of trees propagated by seeds, while four-year-old trees all flowered regardless of propagation methods. Among the domesticated cultivars, all the cultivars from Ganghwa showed abundant flowering with highest nectar production of 6.5 ul per flower, which was 100% more than other domesticated cultivars and 50% more than Debreceni-2 cultivar with highest nectar production among the introduced cultivars from Hungary. At the end of the eight years of observations, two trees of Debreceni-2 cultivars and a tree from Beijing, China were selected for early flowering trees which flowered 2 to 3 days earlier than average trees, while a tree of Debeceni-2 and three trees from Bejing were selected for late flowering trees which flowered 2 to 3 days later than average trees. It is possible to extend the flowering period of black locust by 4 to 6 days by planting early and late flowering cultivars together. Abundant flowering trees were unable to be selected due to severe damages by leaf gall midges which killed many trees and reduced the crown size of the remaining trees in the seed orchard, and which were first found in Korea in 2001 and now damaging most of the black locust forests in Korea. The prediction of flowering period by accumulated temperature indicated that black locust flowered to a peak when accumulated daily maximum temperature reached 880 degrees Celsius, and when daily mean temperature reached 450 degrees.

• FLOWER RESEARCH JOURNAL
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• v.18 no.4
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• pp.271-277
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• 2010

The study is aimed to obtain the basic data for developing new variations of wild spring orchid. The results was investigated the capsules' formational characteristics and the germination ratio after having been self-pollinated by dividing the flowering period into the 5 stages into budding time, semi-flowering, full-flowering, 10 days after flowering, and 20 days after flowering. The fruit setting ratio was the highest as 100% in the plant which had been pollinated 20 days after the flowering, while the weight of the capsule was heaviest in the orchid which had been pollinated in semi-flowering period. As the result of investigating the germination ratio by dividing the period into 5 stages, it was the highest in the plant which had been pollinated during the semi-flowering period, and in the result of investigating the germination ratio by dividing the seeds harvesting days into the 3 stages, such as, 150 days, 165 days and 180 days after the pollination, it was highest as 5% in the orchid whose seeds had been harvested 150 days after the pollination. In the result of examining the germination ratio of the seeds treated with NaOCl, the those treated with 2% of NaOCl showed the highest as 67% in the germination ratio.

• Journal of People, Plants, and Environment
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• v.24 no.4
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• pp.355-363
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• 2021

Background and objective: This study was conducted on Forsythia velutina, a special plant, in Gyeongsangnam-do Arboretum under the Gyeongsangnam-do Forest Environment Research Institute, which is located in the southern part of Korea. Methods: The research aimed to analyze the flowering characteristics of the plant by calculating the optimal temperature and humidity according to the flowering time and flowering period for 8 years from 2010 to 2017 in order to provide basic data for bioclimate studies of endemic plants. Results: It was observed that the Forsythia velutina showed a life cycle from mid-March and to mid-November. Average growth period was 243 (± 6.5) days. In testing the reliability of a single variable according to the meteorological factors, the Cronbach's Alpha was 0.701, which indicates that the findings were relatively reliable. The average date of flowering was March 16 (SD = 5.8) and the average date on which blossoms fall was March 29 (SD = 5.2). A substantial difference in flowering period was observed from year to year 11 to 23 days, with an average of 16 days (± 4.7). The temperature and humidity in February to March, which affect the flowering, were 2.9-5.5℃, and 66.5-73.0%, respectively, and showed differences every year. Conclusion: The correlation between flowering time and meteorological factors was positive, and the highest daily temperature and average daily temperature had the highest significance. When establishing basic data on plant species for the conservation of endemic plants, the changes in life cycle events and weather conditions are identified. It is believed that it will be helpful in establishing a conservation strategy for the plant species in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.3
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• pp.269-272
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• 1981

To know the characteristics of flowering in rape, flower numbers, flowering speed, flowering period, pod numbers, pod formation period, and oil content were examined by individual plant and by each of branches per plant. The results are; 1) plant had in average 1, 400 to 1, 500 flowers, 2) completion of flowering per plant took 30 days, 3) pod numbers per plant was ranged from 560 to 630, 4) plant had 18 to 20 primary branches, 5) five days were needed for pod formation, 6) no difference in flowering speed by the position of branches, 7) flowering period was shortened by 0.5 days per branch by going to upper part, 8) oil content of seeds was significantly higher on the upper and lower part than on the middle part branches.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.2
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• pp.127-134
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• 1989

Several growth characteristics of two ornamental tobacco species, Nicotiana sanderae and N. affinis, were investigated in this study. Also effect of temperature and daylength on the flowering of the tobacco plants were evaluated to obtain basic information on breeding and cultivation. 1. The plants were great in high temperature-long day at the early stage and in low temperature-short day at the late stage of plant growth, for both Nicotana species. At the early growth stage the leaf length N. sanderae was great in high temperature-long day, and that of N. affinis was great in high temperature-short day period, while at the late stage of the plant growth the leaf lengths were more significantly effected by the temperature rather than daylength. Leaf width and leaf shape index were less sensitive to the conditions. 2. For both of the species, the total number of tobacco leaves not much influenced by the temperature and daylength. 3. There were no significant differences for budding and flowering period between the two species, both of which were sensitive to temperature and daylength with more influence by daylength than temperature. 4. Number of floral stalks, number of flower and flowering period were not much influenced by temperature and daylength; however, N. affinis had 2 more floral stalks, 31 more flowers, and 6 day longer flowering period than N. sanderae.

• Journal of Korean Society of Forest Science
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• v.50 no.1
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• pp.5-9
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• 1980

With polyacrylamide gel electrophoresis, peroxidase isoenzyme patterns in the terminal buds of grafted, 20-year-old Pinus elliottii trees were compared between abundant-flowering and poor-flowering trees during the period of female flower bud initiation. A total of nine peroxidase bands were observed in the terminal buds. The total amount of peroxidase enzymes in slash pine buds showed no significant difference between the abundant-flowering and poor-flowering trees. However, the fifth band from the gel front was observed in all the samples of abundant-flowering trees throughout the sampling period (July 8 to September 17), while this band was absent in most of the poor-flowering trees.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.201-207
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• 1993

This study was carried out to ascertain the flowering and boiling habits in conditions of vinyl mulched cultivation. The effects of vinyl mulching cultivation in cotton was early flowering. The flowering period was no more than 26 days and shedding of flower bud was lower. The total boll setting rate to flower number was about 38%. The number of flowering plants was rapidly increased until Aug. 8, then later was decreased, the period of the highest flowering occured was for 5 days from Aug. 6 to Aug. 10. Boll setting was increased that the flowers opened before July 30, then the later flowers was tended to decrease belling in spite of the increased flowering. However flower bud shedding had a tendency to decrease after the highest boiling period. The effect of weather, max. temperature and hours of sunshine on flowering days were highly positive significant correlation. Minimum temperatures, high air humidity and amount of rainfall had a negative significant correlation. The demanded days to flowering on the same internode in each fruiting branches was taken average 1.2 days, these days among the fruiting branches of the same internode was 3.6 days.

• Journal of Plant Biology
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• v.19 no.1
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• pp.14-18
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• 1976

Inhibition of flowering in Lemna perpusilla 6746 by 30 mM sucrose was reversed by the addition of acetylcholine (>$10^{-4}M) supplemented with 10^{-4}M$ ascorbic acid to 1/10-strength Hunter's growth medium. The reversible effect of acetylcholine was found to be greater at early stages of flowering than in the later period. Promotive effects of both acetylcholine ($10^{-3}M) and eserine(10^{-5}M$) on flowering in the short-day plant under various photoperiodic conditions were studied. It was indicated that the application decreased length of the critical dark period for the floral induction, and it was also shown that the endogenous status of acetylcholine was involved in the floral response which had a correlation with phytochrome. Interruption of inductive dark periods by red irradiation (1min) immediately followed by far-red light (1 min) completely inhibited flowering, while the addition of acetylcholine and eserine to the medium under the same condition slightly promoted flowering, indicating possible involvement of phytochrome system in acetylcholine activity for photoperiodic sensitivity of floral response in Lemna perpusilla 6746.

• The Korean Journal of Ecology
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• v.4 no.1_2
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• pp.52-57
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• 1981

I have studied serveral patterns of flowering periods in selected floras of the world since 1969. The total sums and patterns of flowering periods in Netherland, South Germany, France, and Mediterranean and Palestine floras are compared. The total sums of flowering periods of the floras are gradually increased from Netherland to Palestine. The patterns of these flowering periods are characteristic, and divided into two categories; northern temperate and Mediteranean climatic types. The patterns of Netherland, south Germany, and France flora belong to the northern temperate climatic type, and thus the peak of flowering period occur in the month of July. These patterns are particularly belong to the Meditteranean climatic type; and thus the peaks of patterns of flowering period occur in April or May. The Increasing patterns of flowering period from January to April or May seems to be dependent upon the combined factors of satisfactory precipitatiion an dincreasing temperature, while the decreasing patterns since the month of the peak is presumably greatly affected by the scanty precipitation in the high temperature seasons.