• Horticultural Science & Technology
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• v.16 no.4
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• pp.514-516
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• 1998

This study was conducted to observe the effects of urea foliar spray to replace soil fertilization on defoliation ratio, shoot growth and fruit setting in satsuma mandarin (Citrus unshiu Marc.). Twice foliar sprays of 1% urea after harvest increased N and chlorophyll contents in leaves, and decreased defoliation during the winter season. The growth of the ovary and spring shoot was stimulated by the twice 0.8% urea foliar spray around the time of bud emergence. In addition, the treatments increased the number of flowers and fruit setting, but didn't influence fruit quality.

• Journal of Practical Agriculture & Fisheries Research
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• v.24 no.2
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• pp.5-11
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• 2022

Prunus × yedoensis is a representative tree species in residential areas often used as a street tree or park tree, with its popularity due to splendid flowers in the spring. We investigated plant growth, photosynthesis, chlorophyll, and carotenoid concentrations of Prunus yedoensis at 400ml/pot, 1,000ml/pot, and 2,000ml/pot Irrigation treatments. Overall growth indices such as tree height, diameter at root collar (DRC), and total dry weight could be ranked in the decreasing order "2,000ml/pot > 1,000ml/pot > 400ml/pot.". However, 2,000ml/pot featured decreased photosynthesis and total chlorophyll carotenoid contents than 1,000ml/pot treatment after July. And also, The 1,000ml/pot treatment showed relatively high photosynthetic activity and chlorophyll contents. These results suggested that the cultivation of Prunus yedoensis under 1,000ml/pot Irrigation treatment(soil water contents 25~35%) showed the best condition in growth.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.2
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• pp.148-155
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• 2005

An accurate prediction of blooming date is crucial for many authorities to schedule and organize successful spring flower festivals in Korea. The Korea Meteorological Administration (KMA) has been using regression models combined with a subjective correction by forecasters to issue blooming date forecasts for major cities. Using mean monthly temperature data for February (observed) and March (predicted), they issue blooming date forecasts in late February to early March each year. The method has been proved accurate enough for the purpose of scheduling spring festivals in the relevant cities, but cannot be used in areas where no official climate and phenology data are available. We suggest a thermal time-based two-step phenological model for predicting the blooming dates of spring flowers, which can be applied to any geographic location regardless of data availability. The model consists of two sequential periods: the rest period described by chilling requirement and the forcing period described by heating requirement. It requires daily maximum and minimum temperature as an input and calculates daily chill units until a pre-determined chilling requirement for rest release. After the projected rest release date, it accumulates daily heat units (growing degree days) until a pre- determined heating requirement for flowering. Model parameters were derived from the observed bud-burst and flowering dates of cherry tree (Prunus serrulata var. spontanea) at KMA Seoul station along with daily temperature data for 1923-1950. The model was applied to the 1955-2004 daily temperature data to estimate the cherry blooming dates and the deviations from the observed dates were compared with those predicted by the KMA method. Our model performed better than the KMA method in predicting the cherry blooming dates during the last 50 years (MAE = 2.31 vs. 1.58, RMSE = 2.96 vs. 2.09), showing a strong feasibility of operational application.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.294-298
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• 2012

In sweet cherry (Prunus avium L.) growing there are several severe problem which have to be overcome to produce highly graded fruits because of fruit rots and fruit crackings, if there is frequent precipitation during immature fruit step and picking season. In order to reduce fungicide sprayings and produce qualified fruits in areas with rainy season like as South Korea, rain-sheltered growing is necessary absolutely. Sweet cherry blooms early to medium April in southern area of South Korea. If we depend on honeybees (Apis mellifera) distributed in natural ecosystem, it is not easy to get normal fruit-set every season because of low temperature around blooming time. And also bee keepers seldom sell honeybee hives as a pollinator during spring, instead they keep honeybee hives to get honey. Recently use of B. terrestris as a pollinator of cherry tomato, oriental pumpkin etc. grown in protected cultivation system increase abundantly. Therefore, in this study we studied B. terrestris as an alternate of honeybee to pollinate sweet cherry grown in rain shelter. In part of foraging activity B. terrestris shows staying on a cherry flower for about six second and visiting frequency of 11 flowers per minute. However A. mellifera stayed about 15 second on a flower and visited 4~5 flowers per minute. There were no significant difference in fruit-setting rate and fruit characteristics after using B. terrestris and A. mellifera as pollinators of sweet cherry. Consequently there is no negative effect when we use B. terrestris as an alternate pollinator of A. mellifera in sweet cherry cultivation under rain shelter.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.101-105
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• 2012

'Secret Pink' was released by National Institute of Horticultural & Herbal Science in 2008. The cross was made between '03B1-23' and 'Sei-Monaco in 2005'. After the evaluation of the characteristics under shade culture in summer and retarding culture in spring and consecutive selection from 2006 to 2008, 'Secret Pink' was selected finality. The natural flowering time of 'Secret Pink' was the middle of October, and it is possible to flower all year round by shade and light culture. It has single type flowers with pink petals. The growth of plant was very vigorous and response time was 6.5 weeks. The diameter of flower was 6.7 cm. Number of flowers per stem and petals per flower were 14.5 and 25, respectively. Days to flowering under the short day treatment was about 50 and its vase life was 25.5 days in autumn season.

• FLOWER RESEARCH JOURNAL
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• v.19 no.3
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• pp.181-186
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• 2011

A new spray chrysanthemum cultivar 'Yellow Candy' was released by National Institute of Horticultural & Herbal Science (NIHHS), Rural Development Administration (RDA), in 2008. The cross was made in 2003 between 'Restone' and 'Lollipop'. Trials were conducted from 2006 to 2008 for the evaluation and selection of this cultivar, including shading cultures in summer and retarding cultures in spring. The natural flowering time of 'Yellow Candy' is late October, but year-round flowering is possible by photoperiodic control. It has pompon flower type with yellow petals and yellowish red flower center. The growth of plant is very vigorous. The diameter of flower is 4.3 cm. Number of flowers per stem and petals per flower are 8 and 184, respectively. Days to flowering under the short day treatment is about 58.5 and its vase life is 18.5 days in autumn season. 'Yellow Candy' was applied as No. 2009-177 on Feb. 18, 2009 for variety protection and the plant variety protection rights have been registered as No. 3247 on August 3, 2010 at the Korea Seed and Variety Service.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.220-223
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• 2012

A new cultivar $Dendranthema$ $grandiflourm$ 'Dream Water' was developed at Gyeonggi-do Agricultural Research & Extension Services, Korea in 2009. The cultivar 'Dream Water' was initially derived from the cross in 2005 between 'Patra', a spray chrysanthemum cultivar with yellow single type, and 'Ruces', a spray chrysanthemum cultivar with white single type. The cultivar has single type with ivory petals. Trial evaluation was conducted from 2006 to 2009 for selection of this variety, including a shading culture in spring and a retarding culture in summer. The flowering time of 'Dream Water' was October 24th, and year-round flowering is possible by shading or lighting treatment. The diameter of the flower is 56.0 mm. Number of flowers per stem and petals per flower are 11.1 and 26.8, respectively. Its leaf color was green (Green Group 147A) and plant height was 89.7 cm. Days to flowering under the short day treatment is about 54 in spring, and diameter of flower center was 1.4 cm in the summer. The vase life was 16.7 days in autumn and consumer's preference of new spray chrysanthemum is high level than control.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.517-521
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• 2013

A new cultivar Dendranthema grandiflourm 'Dream Round' was developed at Gyeonggi-do Agricultural Research & Extension Services (GARES), Korea in 2010. The variety 'Dream Round' was initially derived from a cross in 2006 between 'Hebo' a seed parent, a spray chrysanthemum cultivar with white anemone type, and 'Samos' as a pollen parent, a spray chrysanthemum variety with white anemone type. The cultivar has anemone type with white petals. Trial evaluation was conducted from 2008 to 2010 for the selection of that cultivar, including a shading culture in spring and a retarding culture in summer. The flowering time of 'Dream Round' was October 24th, and year-round flowering was possible by shading or lighting treatment. The diameter of flower of 'Dream Round' was 34.1 mm. Numbers of flowers per stem and petals per flower of 'Dream Round' were 12.8 and 26.1, respectively. Its leaf color was green (Green Group 147A) and plant height was 92.4 cm. Days to flowering of 'Dream Round' under the short day treatment was about 54 in spring, and diameter of flower of 'Dream Round' was 34.2 mm in the summer. The vase life of 'Dream Round' was 21.7 days in autumn.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.123-127
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• 2013

A new spray chrysanthemum (Dendranthema grandiflorum) 'Blue Hope' was bred by the Flower Research Institute, Gyeongsangnam-do Agricultural Research & Extension Services in 2009. The cultivar 'Blue Hope' was initially derived from the cross in 2005 between 'Ford', a spray chrysanthemum cultivar, with white anemone type, and 'Chopin', a spray chrysanthemum cultivar with white anemone type. The cultivar has anemone type with white petals. After the evaluation of the characteristics under shade culture in summer and retarding culture in spring and consecutive selection from 2007 to 2009, 'Blue Hope' was selected finality. The natural flowering time of 'Blue Hope' was October 24th, and year-round flowering is possible by shading or lighting treatment. The growth of plant was very vigorous and response time 6.5 weeks. The diameter of flower was 4.9 cm. Number of flowers per stem was 19.1 in autumn. Days to flowering under the short day treatment was about 45 in spring and its vase life was 23.8 days in the autumn season. This cultivar was resistance white rust and consumer's preference of new spray is high level than the control.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.196-200
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• 2008

A new spary chrysanthemum (Dendranthema grandiflorum) cultivar 'Pinky' was bred from a cross between 'Rima' and 'Yen'. Progenies were investigated from 2004 to 2006 under shading culture in spring and retarding culture in autumn and the promising line was selected based on the performance of year-round production, white rust resistance and vase life. Pinky flowered around 20 October, and year-round production was possible by shading and lighting. Its flower was 3.1 cm in diameter, and had 38.4 petals and 26.8 flowers per stem in autumn. Its petal was narrow (0.4 cm) and pink with green in color at the flower center. Days to flower from short-day start for 'Pinky' was about 47 in spring. 'Pinky' showed a vase life of 20.9 days in autumn. This cultivar was commercially registered in 2007. 'Pinky' would be suitable for culture under the greenhouse and rain shelter condition in Korea.