• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.179-188
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• 2012

A kiwifruit cultivar 'Hayward' has been grown in Jeju Island where the current climate is suitable for growth and development of this crop. Prediction of the geographical shift in the phenology can help the kiwifruits growers to adapt to the local climate change in the future. Two phenology models (i.e., chill-day and DVS) were parameterized to estimate flowering date of kiwifruits 'Hayward' based on the data collected from field plots and chamber experiments in the southern coastal and island locations in South Korea. Spatio-temporally independent datasets were used to evaluate performance of the two models in predicting flowering date of 'Hayward'. Chill-day model showed better performance than DVS model (2.5 vs. 4.0 days in RMSE). Daily temperature data interpolated at a higher spatial resolution over Jeju Island were used to predict flowering dates of 'Hayward' in 2021-2100 under the A1B scenario. According to the model calculation under the future climate condition, the flowering of kiwifruits shall accelerate and the area with poor flowering might increase due to the warmer winter induced insufficient chilling. Optimal land area for growing 'Hayward' could increase for a while in the near future (2021-2030), whereas such areas could decrease to one half of the current areas by 2100. The geographic locations suitable for 'Hayward' cultivation would migrate from the current coastal area to the elevated mountain area by 250 m.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.3
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• pp.297-304
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• 1983

The water content, respiration rate, solid, and starch contents in the potate tuber of May Queen and Namjak stored at $5^{\circ}C$ and $20^{\circ}C$ were determined during 27 week period. Changes in appearance of the surface and internal tissue also were observed. The dormancy period of May Queen stored at $5^{\circ}C$ and $20^{\circ}C$ was 12 seeks, but Namjak at $5^{\circ}C$ and $20^{\circ}C$ were 9 weeks and 21 weeks, respectively. Greening developed from 12 weeks in the tuber of May Queen at $5^{\circ}C$ and browning of Namjak stored at $5^{\circ}C$ was observed from 6 weeks. In both potatoes stored at $20^{\circ}C$, the rates of respiration were higher than those stored at $5^{\circ}C$, and the rates increased continuously after sprouting at $20^{\circ}C$ but maintained at the low level at $5^{\circ}C$. Solid and starch contents of Namjak were always higher than those of May Queen during 27 weeks, but the levels did not change significantly with time. Solid and starch contents at $20^{\circ}C$ maintained at higher level than at $5^{\circ}C$.

• Journal of Ginseng Research
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• v.23 no.3 s.55
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• pp.130-134
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• 1999

Somatic embryos were induced directly from cotyledon explants of Korean ginseng (Panax ginseng C.A. Meyer) on Murashige and Skoog (MS) medium with 2,4-D, BAP, kinetin or lacking growth regulators. When somatic embryos formed on all media grew to cotyledonary stage, the further development of embryos was ceased and remained in white color. By gibberellic acid (over 1.0 mg/1 $GA_3$) treatment, all the somatic embryos turned rapidly to green and germinated within 3 weeks. Chilling treatment also induced the germination of somatic embryos. The effective temperature regime was $-2^{\circ}C$ for over 8 weeks but more higher temperature than $0^{\circ}C$ did not effective for germination of somatic embryos. Ultrastructural observation revealed that the cotyledon cells of somatic embryos without chilling or $GA_3$ treatment contained numerous lipid reserves, dense cytoplasm, proplastids and non-activated mitochondria with poorly differentiated internal structure, but the cotyledon cells of germinating somatic embryos after chilling or $GA_3$ treatment highly vacuolated and contained well-developed chloroplasts and active state of mitochondria enclosing numerous cristae. The above results indicate that in vitro developed somatic embryos of Panax ginseng may be dormant after mature similar to zygotic embryos.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.45-45
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• 2018

We had already reported the successful germination for green pods of purple lady's slipper orchid (Cypripedium macranthos Sw.). The green pod methods is to take immature seeds in green capsules, sterilize the capsule, and take out the sterile seeds. This method, however, needs very critical time of harvest. The critical time of seed harvest changes depending upon the species, condition of the specimen, and climatic influence, and the right time lies between 5 and 12 weeks after fertilization. In this study, the mature seeds were collected after 120-130 days with hand-polination of lady's slipper orchids. Mature seeds are usually dormant and it has to be overcome, either with hormone or storing the seeds near freezing for two or three months to break dormancy. The seeds were first surface sterilized with 70% ethanol and then transferred 1% NaOCl for 10-15 minutes, followed by rinses 3 times with sterilized distilled water. The cypripedium seeds consists of an embryo within a seed coat known as a testa. The testa is water repellent and the seed has a large air space between the embryo and testa so the seed tends to float on water. We had resolved the problems with vacuum pump to soak water into the testa before sterilization. The seeds were placed on liquid or agar solidified germination media. Cultures were incubated at $24{\pm}1^{\circ}C$ in dark. The seeds were germinated in 6-8 weeks in liquid suspension culture (germination percentage over 18%); however, the seeds on agar solidified media took more than 5 months to germinate and the germination percentage less than 5%. The most effective media for liquid culture was 1/4 strength Murashige and Skoog (MS) medium with 50 ml/l coconut water ($4brix^{\circ}$) at pH 5.8.

• Journal of Korean Society of Forest Science
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• v.38 no.1
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• pp.1-12
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• 1978

This study has intended to disclose the change of some chemical compositions of Ginkgo seeds which were acquired the treatment of cold-moist-stratification after collection. As check sample, the room-stored seeds were used. With the reasons that when the seeds not stratified were sown the delay of field germination has usually been resulted, the effectiveness of stratificaation in respect to alteration of chemical composition is to be investigated. The increase and decrease of growth promoting and inhibiting substances were investigated by means of chromatography method followed by rice seedling test or wheat coleoptile straight-growth test. The results obtained are summarized as follows; 1. In the untreated seeds, the zone of growth inhibitors on paper chromatograph were observed without regard to the tissue differences, embryo, endosperm and seedcoat. 2. Due to stratification, the amount of inhibitor has decreased in the embryo and seed coat, but growth promoters was decreased as compared with the check materials 3. The indications of results appear that each portion of the embryo, endosperm, and seedcoats of Ginkgo biloba L. contains the growth in hibitor taking part in germination dormancy. 4. It was presumed that hastening germination was influenced by decreasing of inhibitors in the embryo and seed coats rather than by increasing of promoters. 5. Gibberellin was detected at Rf 0.26 under the UV-lamp and the abscisic acid was detected at Rf 0.62, Rf 0.70, and Rf 0.78 and showed purple, gray, blue fluorescence respectively under the UV-lamp.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.173-176
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• 2016

This research was performed to breed new columnar-typed apple variety for pollinator in apple orchard. We cross-fertilized 'Hongro' that was an ovary parent and 'Maypole' a pollen parent in 2003. We gathered seeds in 2003 and sowed after breaking of dormancy in 2004. Seedlings was been growth and development till flowering. After fruit setting, We investigated characteristics of growth and fruit including mating compatibility from 2010 to 2012, then finally selected '03-2-95' named 'Tinkerbell' in 2012, registered as new variety on Korea Seed & Variety Service in 2015. The full bloom stage of 'Tinkerbell' was later 2 days then of 'Maypole'. Tree habit of 'Tinkerbell' was alike to of 'Maypole', for example weak tree vigor, columnar type. But there were many different characteristics between 'Tinkerbell' and 'Maypole'. Fruit shape of 'Tinkerbell' was ovoid whereas of 'Maypole' was ellipsoid. Fruit of 'Tinkerbell' was bigger, smoother skin, no waxy bloom than of 'Maypole'. Fruit of 'Tinkerbell' was more delicious than of 'Maypole' because of having higher soluble sugar content and lower titratable acidity. 'Tinkerbell' was excellent pollinator in apple orchard. Because of having high fruit setting rate with major apple varieties and a narrow tree width that was advantageous as pollinator in apple high density system.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.480-487
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• 2006

This study was conducted to improve the germination percent and germination speed by seed priming using polyethylene glycol (PEG) 8,000 solution on Acer mono seed because it has low and irregular germination characteristics. Seed priming was carried out under 0, -0.25, -0.5, -1.0 and -2.0 MPa of water potential at $20^{\circ}C$ for 3 days. Primed seeds showed higher percent germination, germination speed, mean germination time (MGT) and germination performance index (GPI) than unprimed seeds. Especially, primed seed with -2.0 MPa of water potential had the highest germination properties. And primed seeds had a lower dormancy than the unprimed seeds. Relative growth rate and T/R ratio of seedling from primed seeds were measured to survey the effect of seed priming on the seedling vigor as well as seed germination. The seedlings from primed seeds at -2.0 MPa of water potential showed the highest relative growth rates of height and root collar diameter, however, the lowest value in T/R ratio. This study suggested that seeds priming at -2.0 MPa of water potential under $20^{\circ}C$ for 3 days enhanced not only the percent germination, germination speed, MGT and GPI but also the vigor and growth of seedlings in Acer mono.

• Korean Journal of Plant Resources
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• v.22 no.6
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• pp.483-488
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• 2009

The main objective of this breeding program is to develop high yielding, disease resistance and good processing potato cultivar. 'Gui Valley' is a clonal selection resulting from a cross between 'ND2471-8' and 'Cona'. It has medium plant height and light green foliage. 'Gui Valley' has medium flowering habit and light pink flowers. 'Gui Valley' is a medium maturing potato cultivar and tubers are smooth, yellow skin, light yellow flesh, long-oval tuber shape, distinct red eyes with medium depth and medium dormancy. It has high level of tuber uniformity and good keeping quality. 'Gui Valley' demonstrates resistance to potato virus Y (PVY), soft rot, but moderately susceptible to late blight and common scab. It is also resistant to most of the internal and external physiological disorders particularly dehiscence, hollow heart and internal brown spot. The specific gravity of 'Gui Valley' is significantly higher (1.097) than that of 'Shepody' (1.078). 'Gui Valley' has suitable for processing mainly French fries and chips. This cultivar has high level of tuber uniformity and capable of yielding 37.6 $t{\cdot}ha^{-1}$, which is 18.2% higher than the control potato cultivar 'Shepody' under optimum agronomical practices.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.19-28
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• 1987

These experiments were conducted to recognize the germination change in relation to storage period, using 25 kinds of field-collected weed seeds stored under the dry and low temperature ($4{\pm}1^{\circ}C$), and to establish a simple germination induction methods in some kinds of them. No or weak dormancy was observed in Lepidium virginicum, Rumex japonicus, Cirsium japonicum var. ussuriense, Aeschnomene indica and Ludwigia prostrate. The germination of Digltaria sanguinalis, Portulaca oleracea, Amaranthus spp., Echinochloa crux-galli, Polygonum persicaria, Cyperus iria, and Aeschynnmene indica was enhanced by $H_2SO_4$ treatment for 20, 2, 2, 50, 40, 3 or 5 minutes, respectively. Favorable germination in Polygonum persicaria and Echinochloa crus-galli was obtained by soaking in water for 25 days and 50 days, respectively. Moisture treatment for 21 days and 14 days caused the enhancement of germination in Cyperus difformis and Aneilema keisak, respectively. Combination of various treatments in Cyperus iria was most effective when the seeds treated with $H_2SO_4$ for 3 minutes incubated in alternating temp. after soaking in 0.2% $KNO_3$, but their effect on Digitaria sanguinnlis was little.

• Korean Journal of Medicinal Crop Science
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• v.11 no.1
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• pp.46-52
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• 2003

This experiment was conducted to investigate the propagation for mass production of Acanthopanax koreanum NAKAI utilized for health food and medicine material. Germination rate of A. koreanum seeds were 64% when seeds were stored at 15 for 60 days and then were treated with 50 ppm of kinetin and dormancy were broken at 5 for 60 days. Rooting rates of green-wood cuttings treated with IBA 100 ppm, NAA 50 ppm, and IAA 100 ppm were 61.7, 56.7, and 60.0%, respectively. Rooting rates of greenwood cuttings treated with Rooton in scoria + horticulture media and volcanic ash were 76.7 and 66.7%, respectively. Survival rate of seedlings planted on Aug. 10 was highest (96%) under 75% shading net while shoot growth was best under 55% shading net. Survival rate of seedlings planted on May 2 was highest (91%) 55% shading net, and shoot growth was also best 55% under shading net.