• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.3
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• pp.209-215
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• 2007

To improve the accuracy of frost warning system for pear orchard in a complex terrain in Naju area, the daily minimum temperature forecasted by Korea Meteorological Administration (KMA) was interpolated using a regional climate model based on topoclimatic estimation and optimum scale interpolation from 2004 to 2005. Based on the validation experiments done for three pear orchards in the spring of 2004, the results showed a good agreement between the observed and predicted values, resulting in improved predictability compared to the forecast from Korea Meteorological Administration. The differences between the observed and the predicted temperatures were $-2.1{\sim}2.7^{\circ}C$ (on average $-0.4^{\circ}C$) in the valley, $-1.6{\sim}2.7^{\circ}C$ (on average $-0.4^{\circ}C$) in the riverside and $-1.1{\sim}3.5^{\circ}C$ (on average $0.6^{\circ}C$) in the hills. Notably, the errors have been reduced significantly for the valley and riverside areas that are more affected by the cold air drainage and more susceptible to frost damage than hills.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.651-654
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• 2011

Cymbidium 'Orange Bowl' (Lucky Rainbow 'Randevous' ${\times}$ 'Eastern Star') was developed from a cross between hybrids at the National Institute of Horticultural & Herbal Science, Rural Development Administration in 2006. A cross was made between the pink colored flower C. Lucky Rainbow 'Randevous' as maternal line and pure yellow colored flower, C. 'Eastern Star' as paternal line in 1995. The seed germination, cultivation, selection, and characteristic trials were conducted from 1996 to 2006. The line was named as Wongyo F1-18 and phenotype was characterized in 2006 as a new 'Orange Bowl'. The 'Orange Bowl' has having light yellow basal color (RHS, YO21D) and orange line (RHS, OR30B) on both of sepal and petal with red lip (RHS, OR30B). 'Orange Bowl' has about 10.9 flowers per flower stalk and flower size of 7.4 cm. General appearance of the petals and sepals is slightly incurved shape. The plant size is intermediate having erect peduncle. Blooming is started from the late of January (mid winter) under optimal culture condition. Leaf attitude and twisting is half- erect and very weak respectively. This hybrid has attractive floral arrangement, long flower stalk (71.8 cm) and vigorous growth. We expect that 'Orange bowl' has a great potential for exporting to Chinese market.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.269-275
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• 2014

A standard rose cultivar, 'Love Letter' was selected for cut flower from the progenies of a cross between 'Red Giant' and 'Ensemble' by the rose breeding team of the Gyeonggi-do Agricultural Research & Extension Services (GARES) in 2011. A standard rose cultivar 'Red Giant' with red colored (RHS Red Group 45C) petals and 1.8 prickles per stems of 10 cm was used as a mother plant. A standard rose cultivar 'Ensemble' with white and red purple colored (RHS White Group 155C + RHS Red Group N57B) petals and 2.4 prickles per stems of 10 cm was used as a pollen parent. 'Love Letter' was crossed in 2007 and seedlings were produced. After tests of specific characters from 2008 to 2011, this cultivar was finally selected and named. As a standard type with large sized flower, it has red colored (RHS Red Group 46A) petals with 9.3 cm flower diameter and 32.4 petals per flower. Vase life of this cultivar could be as long as 12 days. It takes 43 days from pruning to blooming and cut flower productivity was 152 stems/$m^2$ in a year. The stems of cut flower have no thorn and the length is about with 70.5 cm. When this cultivar grew below $15^{\circ}C$ and 1,000 lux, the petals color became dark red in winter season. 'Love Letter' was registered as a new cultivar on Korea Seed & Variety Service (KSVS) with No. 4482 on May 8, 2013.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.3
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• pp.45-49
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• 2020

The aims of this study is to land improvement effect of sewage sludge dry fuel mixture. The mixing ratio of sewage sludge and dry fuel was mixed at a weight ratio of 1:1 to make a mixture, experimental designone was designed as one control (0 %) site and three test groups that each mixture of 10 %, 20 %, 30 % was added. Comparison of yield after cultivation of Kenaf 90days, in the 10 % test group the length of the stem increased by 73 % compared to control site and 20 % test group the leaf yield increased by 227 % compared to control site. It is judged that the growth rating the blooming of 30 % test group is faster than and the chlorophyll content is the highest(71.6SPAD) that of another control. In conclusion, the addition of dry fuel mixtures is effective in improving overall soil quality for plants to live.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.1
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• pp.17-22
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• 2013

In this study, a pH control method by carbon dioxide ($CO_2$) was applied to coagulation process in water treatment plant (WTP) to investigate the coagulation efficiency and residual dissolved aluminum when high pH raw water is flowing into the plant during algal blooming. Existing coagulant dose (1 mg/L in raw water) resulted in the pH reduction of 0.0384 by LAS, 0.0254 by PAC, 0.0201 by A-PAC, and 0.0135 by PACS2, respectively. And then the concentration of dissolved aluminum was 0.02 mg/L at pH 7.44, 0.07 mg/L at pH 7.96, 0.12 mg/L at pH 8.16, 0.39 mg/L at pH 8.38 showing the concentration increase with pH in the coagulation process. It was noteworthy that rapid increase was observed at pH above 8.0 next the rapid mixing. Therefore it is necessarily required to control pH below 7.8 in the coagulation process in order to meet drinking water quality standard of aluminum for high pH raw water into WTP, $CO_2$ injection could control pH successfully at about 7.3 even for the raw water of high pH above 8.0. In addition it was found that the pH control by $CO_2$ injection was significantly effective for coagulation in terms of turbidity removal, coagulant dosage, and residual dissolved aluminum concentration.

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.549-556
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• 2011

We investigated the plant phenology on the threatened species for climate change in the summit area of Mt. Deogyusan which is a representative sub-alpine zone in Korea. We had performed the monitoring survey of plant phenology on 38 species including 20 trees and 18 herbs from May 2009 to November 2010. The investigated phenological charateristics were five dates for leafing, flowering, floral abscission, autumn leaf colors and leaf abscission on each plant species in sub-alpine region. The climate data were measured from November 2009 to December 2010. The range of temperature was from 30.4 to -$20.3^{\circ}C$ at Hyangjeokbong to Jungbong region, and the relative humidity was 100% to 3.4%. The leafing dates in 2010 were similar to 2009 or were 6-20 days delayed in most of the investigated species except Veratrum oxysepalum and Sanguisorba hakusanensis which showed 8 days earlier leafing dates in 2010. The biggest difference among phenological characters was found in flowering dates. The flowering dates of early Spring blooming species such as Heloniopsis koreana, Rhododendron yedoense for. poukhanense and Viola orientalis showed 13-20 days earlier in 2010, and the several summer flowering species as Viburnum opulus var. calvescens, Smilacina japonica and Bupleurum longeradiatum showed 6-10 days delay in 2010. The dates for floral abscission and autumn leaf colors in 2010 were delayed about 10-18 days, and leaf abscission dates were similar to 2009. The effects of climate change on the phenology for the threatened species in sub-alpine zones of Korea are occuring especially on flowering, floral abscission and autumn leaf colors.

• Korean Journal of Plant Resources
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• v.31 no.1
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• pp.71-76
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• 2018

This study was conducted to investigate the effect of shoot twist on fruitfulness and fruit quality of 'Campbell Early' grapevine. Proper pruning and training are essential to produce a good yield of high-quality fruit and to maintain the balance between vegetative growth and fruiting. The most common problem in spur-pruned 'Campbell Early' cultivar is that vigorous buds has low fruitfulness and thereby the shoot become more vigorous the following spring because of lower crop load. Therefore, shoot twists in very vigorous 'Campbell Early' canes (above 10.0 mm) were performed on the third nodes and the $7^{th}$ nodes of each shoot at 7 days before bloom and full bloom, respectively. Sprouting date, blooming date were not significantly different among the treatments while, harvesting date was delayed approximately 3 days. However, number of berries per cluster, cluster weight and fruitfulness were significantly higher in the shoot twist treatment on the third nodes than the control that was topping alone. Combination treatments of shoot twist and topping had an additive effect on increasing cluster weight resulting in higher increase of yield by 12.1 ㎏ per vine. These results indicated that the shoot twist on very vigorous canes of 'Campbell Early' grapevine for well fruitfulness seemed to be very effective.

• Korean Journal of Plant Resources
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• v.18 no.3
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• pp.382-389
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• 2005

This study was conducted to establish the system of effective in vitro propagation by various explant sources culture of Bippeastrum hybridum Hort, 'Dazzler'. We tested the effects of optimal explant source, plant growth regulators on bulblet formation and plant regeneration. Callus was readily produced on the different tissues excised from floral buds whereas, bulbs and shoots were formed only on pedicel explants as compared with anthers, styles and ovaries. Pedicel is the best optimal explant for in vitro propagation. Two distinct pathways, organogenesis through callus and direct bulblet formation, could be recognized in pedicel culture. Up to the $80-100\%$ of bulblet formation and shoot organogenesis from the pedicel in fifteen days before anthesis were effectively induced by MS medium supplemented with 0.5 mg/L NAA and 1.0 mg/L BA. Plantlet regeneration was successfully achieved from pedicel-derived callus, via shoot bud induction or direct bulblet formation. The bulblets with blooming flower were produced within 2 years.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.571-575
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• 2014

'Dream Song' is a cultivar of Gypsophila paniculata developed by the Jeollabuk-do Agricultural Research & Extension Services in 2010 for cut-flower production. This hybrid was bred from 121 seedlings collected from an open-pollinated population of 'Gyp06-11'. It has novel morphological characteristics of upright plant type, lanceolate leaves, double florets with a few bright white-colored petals of obovate shape, truncate petal tips, and cup-shaped calyces. Furthermore 'Dream Song' has desirable cultivation characteristics including narrow branching angle, and moderate resistance to powdery mildew, thrips and leaf miners. Moreover it produces more primary branches, and longer internodes and flower stalks than reference cultivar 'Bristol Fairy' during summer cultivation in a subalpine area (500 m over the sea level). Flowering in 'Dream Song' is delayed by about 17 days as compared to 'Bristol Fairy'. 'Dream Song' produces normal flowers with 2 pistils and an average of 10.4 stamens, with fewer malformed flowers than 'Bristol Fairy'.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.159-164
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• 2013

A white powder-like substance, so called 'bloom', is formed on the surface of fruits of many varieties of cucumber. Although it is a natural phenomenon, bloomed fruits are accepted lower in quality compared to bloomless fruits by consumers. The experiments were conducted to obtain basic informations for breeding rootstocks, and to develop promising bloomless rootstocks from basic source materials collected and selected by seed company. The surfaces of bloomless fruits were appeared on the bladder cell of glandular trichome and the epicuticular waxes. Those of bloom fruits appeared with an injured bladder cell and many particles, which were not seen on those of bloomless fruits. The chromaticity was investigated on the surface of the bloom and the bloomless fruits. The 'a' and 'b' value of the bloom and the bloomless fruits did not show any significant difference. The 'L' value was significantly different and that of bloom fruits was higher than that of bloomless fruits. Fruit Si content was conspicuously lower in the fruits of cucumber plants grafted on the bloomless rootstock than in the fruits of those grafted on general bloom rootstocks.