• Horticultural Science & Technology
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• v.28 no.4
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• pp.711-714
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• 2010

A new cultivar 'Daemang' ($Hibiscus$ hybrid 'Daemang') originated from the interspecific cross between $Hibiscus$ $sinosyriacus$ 'Seobong' and $Hibiscus$ $syriacus$ 'Namwon' to improve the flower quality in 2001. 'Daemang' was preliminarily selected as 'R-143' in 2003 for its stable flower quality with long red eye spot and named in 2006. The tree habit shows vigorous growth and is upright, so it can be used as a specimen tree or street tree. Characteristic tests such as leaf shape, leaf size, flower characteristics, flowering, and capsule size were conducted from 2004 to 2006. The characteristics succeed after grafting. 'Daemang' had pink color flower with red eye spot. The width of flower is 15.2 cm. Petal length and width are 8.0 cm and 6.4 cm, respectively. Leaves are 9.49 cm long and 8.72 cm wide. After the plant characteristics evaluation for 3 years (2004~2006), it was registered as a variety 'Daemang' in 2008.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.4
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• pp.440-448
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• 1989

The present experiment was conducted to investigate the effects of seeding date on agronomic characters including seed weight of soybean (Glycine max (L.) Merr.) at Sunchon, the southern coastal area of Korea. One hundred eighteen native and improved varieties were used in this study. As the seeding date was delayed, the number of days to flowering for the cultivars was reduced. This trend was more obvious in late maturing cultivars(LMC) than in early and medium maturing cultivars (EMC and MMC). Late seeding also resulted in decrease in the number of leaves, stem length, and number of nodes. The heaviest seed weight was obtained with EMC and MMC planted on May, and seed weight decreased with delayed seeding date. Seed weight was positively correlated with number of days to flowering, number of total leaves at flowering, stem length and number of nodes on main stem at maturity. Based on seed weight the cultivars was classified into five types: Type I; Seed weight of the cultivars decreases with delayed seeding date. Type II; Seed weight of the cultivars does not vary with seeding date. Tyep III; Seed weight of the cultivars increases with delayed seeding date. Type IV; Seed weight of the cultivars increases when the seeding date approached the appropriate seeding date, but decreases thereafter. Type V; The reversed type IV. Type I, II, III, IV and V occupied 37, 16, 17, 10 and 20％ of the tested cultivars, respectively.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.539-548
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• 2011

This study was conducted to control unseasonable flowering in a standard chrysanthemum 'Baekma' bred in Korea by 2-chloroethylphosphonic acid (ethephon) and night temperature (NT) through suppression of the transition from a vegetative to a reproductive stage under long day length caused by high NT in summer season. Ethephon was applied either once or twice at a concentration of 0, 200, 400, or $800mg{\cdot}L^{-1}$. The NT within controlled mini-plastic houses was maintained at 13, 17, or $21^{\circ}C$. The NT at $13^{\circ}C$ showed the greatest inhibiting effect of unseasonable flowering among all NTs regardless of various combinations of ethephon concentration and frequency. Moreover, the inhibition tendency of unseasonable flowering was distinctly decreased in a NT-dependant manner. Higher NTs reduced cut flower length and number of leaves, but increased the number of young leaves attached to top part of the flower. Higher ethephon concentrations and lower NTs increased cut flower length and the fresh weight of total, stem, and leaves due to the extension of vegetative growth period. Thus, if it is difficult to control the NT below $21^{\circ}C$ in greenhouses in the summer season, we recommended to spray more than $200mg{\cdot}L^{-1}$ ethephon once after planting to suppress unseasonable flowering and to ensure sufficient length of cut flowers.

• Journal of Bio-Environment Control
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• v.17 no.2
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• pp.176-180
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• 2008

In days to calyx-flex stage test, flower development affected by light intensity, light duration and the prevailing temperature. As, 'Jacaranda' variety shorter in under 46 days of flower bud formation and 13 days of calyx-flex stage than the other variety with 'Queen Elizabeth' control variety. About cut flower only 'Grand Vicki Brown' (as within 46 days of flower formation, 13 days of calyx stage and 'Jacaranda', both with shorter plants than the other varieties produced cut flower classified as short and medium-stemmed cut flowers. 'Jacaranda', 'Vicki Brown', 'Golden Times', 'Champagne', 'Osiana', and 'Queen Elizabeth (control variety)' flowered earlier from 46.7 to 50.8 days from pruning. Flower development was likewise faster in all the above mentioned cultivars; while 'Tineke' had significantly delayed flower development reaching calyx-flex stage from 0.5 cm bud size after 51.0 days. The top ten high yielding varieties were 'American Orange', with a net income of P3,081,676.00; 'Yellow Island' with P1,572,874.00; 'Frosty Pink' with P1,085,183.00; 'Champagne' with P980,620.00; 'Coral Pink' with P959,669.00; 'Lara Pink' with P918,444.00; 'Lara Orange' with P714,252.00; 'Grand Gala' with P705,787.00; 'Golden Times' with P806,489.00; and 'Lady X' with P778,060.00 net returns.

• Korean Journal of Plant Resources
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• v.18 no.3
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• pp.433-440
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• 2005

Four varieties of perilla(Perilla ocimoids L.) were tested to investigate the ecological adaptation of the crop to variations in sowing time extending from April 25 to July 25 with an interval of 30 days between each of the four sowing. As sowing time was delayed, the plant height, the number of first branches and cluster, the weight of fresh and dried stems, the day to germination and flowering decreased, showing a highly negative correlation between the showing dates and these characteristics, but a highly positive correlation between days to flowering and the required accumulated temperature. With early sowing under low temperature and long day conditions, it took about 132 days from sowing to flowering due to the long period of vegetative growth, but as sowing was delayed, the days to flowering decreased with a minimum period of 57 days. The yield of seeds in each case varied with each variety. Type A(Nonsan var.) and type B(Jinchon var.) had higher yields when sowed earlier. But type C(Namyang var. and Wooljin var.) had its highest yield in the plot sowed on May 25 and the 1000 grain weight showed a tendency to increase as sowing was delayed. In conclusion, the perilla was preyed to be a short-day plant that flowers from the begining to the middle of Sep. regardless of sowing time, so that the sowing time should be decided after due consideration of the length of the vegetative growth periods of the varieties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.4
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• pp.59-65
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• 1980

An attempt was made to survey soybean cultivars that were nonsensitive to the photoperiod for selection as possible breeding materials for wide area adaptable varieties. Fifty-five cultivars were subjected to different day length conditions. The number of days from sowing until flowering was shortened under short day length conditions, and late varieties tended to be more sensitive to day length than early varieties. The response to day length of the tested cultivars might be divided into three groups; low, intermediate and high degree, by their accelerated rate of flowering. Especially four varieties in the low responding group, Gembokin, Wirth, Wayne and Pi.54613 were identified to be nonsensitive to day lengths, that is, neutral varieties. They also showed little variation in morphological characteristics under different day length conditions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.43-48
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• 1986

The experiment was conducted to know the varietal difference in changing aspect of daily filling sink during of rice using three cultivars; ‘Suweon 295’ (japonica), ‘Suwoen 264’ and ‘IR 1317-70-1’ (semi-dwarf indica) cultivated in the field and green house of the Crop Experiment Station in 1983. There was not significant varietal difference in flowering habit and duration of flowering period each panicle. Semi-dwarf indica cultivars showed shorter days to physiological maturity of rice kernel than the japonica one. The former also displayed earlier decrease in water content of rice grain during ripening than the latter. Japonica variety revealed larger difference in ripening advancement between vigorous florets and inferior one than semi-dwarf indica varieties. The semi-dwarf indica rice cultivars expressed significantly shrewder parabola of daily filling of sink per panicle during ripening than the japonica one. The time showing maximum capacity of daily filling of sink per panicle during ripening was 10-12 days after anthesis. The filling capacity of daily sink filling per panicle for 'IR 1317-70-1', 'Suweon 264' and 'Suweon 265' at this time were about 240 mg, 165 mg and 145 mg, respectively. Pattern of sink filling per panicle during ripening was slightly changed by the cultural environment. ‘Suweon 295’ showed slightly sharper parabola and 2-3 days earlier time showing maximum capcity of daily sink demand per panicle during ripening in the field than those in the green house.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.216-220
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• 2002

This study was conducted to know the change pattern of chemical components, especially proximate constituents, saponin and free sugars in roots of 4-year ginseng according to different harvesting time, and to find out the optimum harvesting time on the basis of chemical components in fourth year ginseng root. The crude protein content was 20.77% of the highest on the April (shootinzg stage),13.13% of the lowest on the June among all growing stages, and was constant at 17% after the August. But crude oil and fiber contents showed the highest value on the May (flowering stage). The content of total sugars which was the largest constituent among the chemical components in ginseng root was in the range of 60~7(1% during the all growing stages. It showed the highest value of 7l% on the June, but the lowest of 60% on the May. The total free sugar contents was the highest on the April (20.40%), but the lowest on the May (11.89%). The change pattern of sucrose contents (10.96-19.60%) was same as the total sugars contents (11.89-20.40%), on the other hand, the contents of glucose and maltose were not changed significantly during all harvesting times. The contents of crude saponins and total ginsenosides had the value of 7.60% and 4.09% on the May, respectively. That was statistically significant, but the other harvesting times were not. Therefore, on the basis of the only chemical characteristics in the four year-old ginseng root, we suggest that the harvesting on the May at flowering stage was most proper time.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.146-152
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• 2013

The photosynthetic rates according to leaf positions in tomato plants were investigated in relation to leaf age and flowering rate. In the experiment investigating the diurnal change of photosynthetic rates, three leaves below the 4th cluster was checked every hour from 2 hours before sunrise and 3 hours after sunset. It was checked twice with the replication of 3 plants. The photosynthetic rate increased sharply for 1 hour right after sunrise and remained steady until 2 hours before sunset. This trend can be applied to determine the irrigation schedule. In the experiment investigating the photosynthetic rates according to leaf positions, it three leaves below each clusters from 1st to 4th cluster were checked. Flowering rate was also investigated. The photosynthetic rates showed a decreasing tendency steadily after flowers bloomed fully, regardless of the leaf position. It seems to be because the leaves below the cluster with fully-bloom flowers lost their activities. This result suggests the flowering rate or the position of flower has deep relation with the photosynthetic rates of the concerned leaves. From the results the leaves under flowering cluster may be the good part to investigate the photosynthetic rate to evaluate the crop's activity, even the photosynthetic rates are different according to the position of clusters.

• Journal of Bio-Environment Control
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• v.19 no.3
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• pp.165-170
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• 2010

This experiment was conducted to select the affected main factors on growth and fruit characteristics of 'Fuyu' persimmon (Diospyros kaki Thunb.) in 25 factors of air temperature factors in Naju. Mean air temperature, cumulative temperature and days for March and April of 25 factors were the highest annual variation. Number of the first and second principal components extracted from 25 air temperature factors were 14 and 3 factors related with mean temperature for annul and April, and cumulative contribution of these was 52.2%. Also the affected years by the first principal components were 1990, 1980 and 1986. Annual standard deviation on leafing, flowering and maturing date were 4.0~6.7 days range, and flowering date and days from leafing to flowering had the highest coefficient of variation. Annual variation of days from flowering to maturing date was affected by greatly mean air temperature and days of cumulative temperature in October, days from March 1 to leafing date was affected by cumulative temperature for growing period, days from leafing to flowering date was affected by mean air temperature in April. Annual variation of fruit weight was affected by mean air temperature for March and October.