• Journal of Plant Biology
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• v.35 no.4
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• pp.403-408
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• 1992

The flowering in Lemna gibba G3, a long-day plant, was promoted under continuous light by agmatine, putrescine, spermidine and spermine present in the culture medium. Methylglyoxal-bis (guanylhydrazone) (MGBG) and cyc10hexylamine (CHA), inhibitors of polyamine biosynthesis, were found to suppress the flowering in the plants. The vegetative grov.1h rate was kept constant while the flowering was being promoted by the pOlyamines, and the inhibitors with depressive effect on flowering showed stimulatory effect on vegetative grov.1h. The pattern of vegetative growth during floral promotion or depression was an indication that the promotive action of the pOlyamines and the suppressive effect of the inhibitors may be outcome of their possible involvement specifically in the flowering process rather than in broad spectrum of growth of L. gibba G3. The degree of promotive action of spermdine and spermine could not be altered (or lessened) by simultaneous application of their inhibitors to the medium. This phenomenon indicates that the flowering process in L. gibba G3 may largely be dependent to the status of endogenous spermidine and spermine. Endogenous level of spermidine in florally induced Lemna, was found to rapidly increase. In 24 h of floral induction, the content reached at the level 2 times higher than that in non-induced plants. The elevated level of spermidine provides an additional, though premature, evidence supporting the postulation that endogenous polyamine status might play an important role in the very early stage of floral induction in L. gibba G3.bba G3.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.618-623
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• 2015

The new white calla lily (Zantedeschia aethiopica) cultivar 'White Cutie' was bred at the National Institute of Horticultural & Herbal Science (NIHHS) in 2011. 'Childsiana' showing the multi-flowering characteristic and 'Wedding March' resistant to soft rot disease were artificially crossed in 2004. Of the progeny, 'White Cutie' was selected specifically for use in cut flower production after investigation over seven years (2005 to 2011) of genetic and phenotypic characteristics, resistance against soft rot, and customer preference regarding the culture vigor and post-harvest quality. 'White Cutie' was early flowering (85.6 days to flowering) with white flowers (RHS W155C), although it had a mid-sized flower in which spathe height and width were 8.6 cm and 8.7 cm, respectively. It was multi-flowering (6.2 flowers per plant) and produced a very high number of cormels (13.4 per plant). Furthermore, it was resistant to soft rot disease.

• Journal of Korean Society of Forest Science
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• v.96 no.6
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• pp.699-704
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• 2007

This experiment was conducted to investigate growth and flowering characteristics of Iris koreana and Iris minutoaurea Makino native to Korea for potting plant of early spring treated by forcing date and temperature. As forcing date delayed from November 1 to December 1, the plant height and number of leaves were increased, however no difference in the number of flower and date of flowering. In Iris koreana, the plant was not flowering in forcing on November 1, flowering 30% on November and 100% on December 1. However all the forcing plant flowered in Iris minutoaurea Makino. As forcing temperature increased from $7^{\circ}C$ to $15^{\circ}C$, the plant height and number of leaves were decreased, however the number of flower in $7^{\circ}C$ was increased and date of flowering was earlier than ones of higher temperature. In Iris koreana, the plant was not flowered in forcing $12^{\circ}C$ and $15^{\circ}C$, all flowered in forcing $7^{\circ}C$. Iris minutoaurea Makino was flowered 30% forcing in $12^{\circ}C$ and all flowered forcing in $7^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.14
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• pp.133-137
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• 1973

In order to classify the ecotypical and maturing groups 136 Korean local and 4 Japanese Perilla varieties were sown at Suwon on May 20, 1972, and investigations were made on days to flowering, days to maturing and growth duration. Results obtained were summarized as follows: 1. Ecotype was classified from 6 groups with combination of the long and short duration from sowing to flowering and maturing period. The classified symbols of groups were Ia, Ib, IIa, IIIa, and IIIb. I: long duration. to flowering II: medium duration to flowering III: short duration to flowering a: long duration to maturing b: short duration to maturing Korean local varieties were distributed 3 ecotypes of IIa, IIb and IIIa, however, Japanese varieties did 2 ecotypes of IIa and IIb, respectively. 2. Maturing group was classified from 3 groups with long (I), medium (II), and short (III) growth durations. Korean local varieties belong to II and III groups but Japanese varieties belong to I and II groups, respectively. 3. Three were highly significant positive correlation (0.685) between ecotypical and maturing group. Ecotype was more related with days to flowering and growth duration, however, maturing group was related with days to flowering, days for maturing, and growth duration. Korean local varieties, more distributed into ecotype than maturing group, were attributed to differences of environmental conditions and cultural practices at different provinces.

• Korean Journal of Environment and Ecology
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• v.29 no.3
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• pp.441-453
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• 2015

In this paper, according to the illuminance at night with artificial lighting in downtown Seoul, trees flowering and leaf growth rate was performed as a case study to examine whether there is a difference. The illuminance was measured at 78 points on a total of 26 points, the range of illuminance were divided into three groups considering land use, Group A (plots 1-7) were 4.90 ~ 112.50 lx, Group B (plots 8 to 18) were 0.45 ~ 42.40 lx, group C (plots 19 to 26) were 0.28 ~ 22.10 lx. According to the One-way ANOVA on illuminance difference, the survey groups were classified into three groups. To survey the ratio of the flowering Prunus yedoensis and Rhododendron spp. and to survey the ratio of leaf growth Zelkova serrata, Ginkgo biloba, and Acer palmatum each 30 individuals were investigated. Rhododendron spp. to study the ratio of the flowering and Acer palmatum to study the ratio of leaf growth were determined to be useful as indicator woody species according to the correlation. The higher illuminance of night lighting is, the faster flowering and leaf growth of trees will be by correlation between the mean illuminance of each group and the flowering and leaf growth of trees. In the future, should be made a more detailed study of how much affect to the trees with some impact on the level of light pollution at night lighting.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.2
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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.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.89-94
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• 2013

This study was carried out to calculate the genic values of days for flowering in commercial breeding lines of Korean hot pepper (Capsicum annuum L.). Two breeding lines of pepper '#2132' ($P_1$) early-flowering, and '#1308' ($P_2$) medium-late flowering, and their $F_1$ and $F_2$ generations were used in this study. By using partitioning method (Thseng and Hosokawa, 1971, 1972), it was possible to estimate, from the $F_2$ generations, the number of effective factor pairs differentiating the two parents. It was found out that the two parents were differentiated by two effective factor pairs, A:a and B:b. In the breeding lines used, the inheritance of days to flowering showed that the $F_1$ flowered a little earlier than the earlier flowering parent through the effect of over-dominance. However, $F_2$ flowered earlier or later than both parents through transgressive segregation. Conclusively, the magnitude of genic effects of A-a gene in flowering days was -13.81 days, and B-b gene was -6.73 days. The interaction between the two non-allelic factors using partitioning method was -5.26 days.

• Current Research on Agriculture and Life Sciences
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• v.22
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• pp.1-12
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• 2004

Pod-edible bean or snap bean is a fairly new crop to domestic farmers but the national demand is steadily increasing in recent years along with the development of western food business and change in dietary patterns. At the same time, much efforts are being made to export it to foreign country, mainly to Japan. The amount of seeds introduced from outside is also continuously increasing along with the enlargement of area planted for the crop. Hybridization breeding for the crop has already been started to supply the cheaper and better seeds which will reduce the seed costs and foster the higher income to the farmers. In this experiment, several technologies related with the production of quality seeds are preliminary investigated. Some of the results obtained are summarized as follows; 1. Highly significant interaction was recognized between planting dates and no. of pods per plant and no. of branches but no interaction between planting dates and plant height and no. of nodes on main stem. Days to maturity was proportionally reduced to later planting dates. 2. Rate of viviparous pods and seeds was gradually increased in later planting dates but rate of germination was increased in earlier planting dates with lower germination rate in white seed coat grains than in colored seed ones. 3. Seed yield was higher in the earlier planting dates with a great deal of varietal difference. Early to mid April was considered to he the optimum planting dates for snap bean in Kyungbuk area. High correlation was recognized between seed yield and no. of pods per plant, no. of seeds per plant, and 100 seed weight. 4. Days to flowering was three and seven days longer in Cheongsong, high mountainous area than in Kunwi, somewhat prairie lowland. One hundred seed weight was also higher in Cheongsong than in Kunwi. Rate of viviparous grains, pods, and decayed seeds was higher in Cheongsong but, at the same time, the rate of germination and seed yield was also higher in Cheongsong. 5. One hundred seed weight of KLG5007 increased continuously up to 35days after flowering and decreased thereafter but that of KLG50027 increased to 40days after flowering and slowly reduced thereafter. The content of crude oil reached to maximum at 40 days after flowering and reduced thereafter. The rate of germination in Gangnangkong 1 was the highest, 89.3%, at 35 days after flowering and reduced thereafter while that in KLG50027 reached to maximum, 70.7%. at 40days after flowering and reduced thereafter. Thus, the optimum harvesting time for snap bean was considered to be 35~40days after flowering. 6. The snap bean pods at yellow bean stage easily became viviparous ones under saturated moisture conditions for 24 hours at $25{\sim}30^{\circ}C$. Therefore, it is recommended to harvest pods somewhat earlier than yellow-bean stage and let them do post maturing, especially when it is to be rained.

• Korean Journal of Plant Resources
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• v.34 no.5
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• pp.462-469
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• 2021

Maesa japonica (Thunb.) Moritzi & Zoll. is a rare evergreen shrub that occurs in west Gotjawal, Jeju island, Korea. This study was conducted to investigate effects of an artificial shading on flowering and growth characteristics of M. japonica seedlings. The level of shading had been set to be 35%, 55% and 75% using shading net. The stage of flowering and flowering ratio, seedling height, the number of leaves and stems, leaf area were measured. Flowering timings were delayed by shading. The number of flowering seedlings per plot and inflorescences per seedling were the most in 55% shading level. Tendency of decreased seedling height with increased shading level was shown. The number of leaves and stems were the fewest values in 75% shading level. The increased biomass with decreased shading level was statistically significant. Aboveground and underground biomass were 2.1 and 1.7 times higher in shading 35% than in shading 75%, respectively. Meanwhile, all seedlings in non-shading plots were dead in winter. Such might be speculated as results of the light stress. As a result, we conclude that M. japonica vitally demands the shading for growth and the optimal shading levels for growth and flowering are 35% and 55%, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.436-441
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• 1985

The study was conducted to provide basic information to breeders and agronomists working with sesame. The grain weight and germinability were investigated for eight plant types classified by branching habit, capsules per axil, and carpels and loculi of a capsule. Two typical cultivars were chosen for each plant type among 527 gene pools. Dry weight of one thousand grains was increased rapidly from 25th to 35th day after flowering, and reached peak on 40th day after flowering in upper part capsules and 45th day after flowering in lower and middle part capsules, so that this period was considered to be of physiological maturity in each capsule bearing part. Side capsules on main stem and branch capsules were lighter than central ones of main stem, and upper capsules of four carpels eight loculi type decreased more seriously. BTB type demonstrated relatively better growth compared to the growth of BTQ type in one thousand grain weight. The maximum grain filling duration for germination percentage increased rapidly up to 40th day after flowering. Above 70% germinability was obtained from 40th day after flowering. Harvesting time of physiological maturity was considered to be 45th day after flowering with peaks of 2.14g of one thousand grain weight, 26% of grain water content and 90% of germinability.