• Korean Journal of Medicinal Crop Science
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• v.21 no.5
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• pp.329-333
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• 2013

This study was carried out to compare the characteristics of seed germination and the first stage of growth in Cynanchum wilfordii (Maxim.) by different light conditions such ass fluorescent light, dark and light emitting diode (LED). There was not much difference from the germination rate of C. wilfordii (Maxim.) in different light conditions for 10 days. The highest of germination rate occurred over 91.11 percentage by LED red condition at $26^{\circ}C$. Also mean germination velocity and promptness index were represented the highest results of 2.3 ea/day and 52.67 under red light, respectively. But mean germination time under both LED red and blue light was represented low data that it takes over three days for germinating of seed. Even though handling both LED red and blue lights, the germination uniformity was not constant. These results may help our understanding of variations in germination characteristics for C. wilfordii (Maxim.) seeds treated under different light conditions.

• Korean Journal of Medicinal Crop Science
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• v.27 no.3
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• pp.167-172
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• 2019

Background: Angelica acutiloba Kitagawa belongs to the flowering plant family Apiaceae. Its young leaves are consumed as a vegetable, and its roots have medicinal properties. This study was conducted to analyze the seed germination characteristics of A. acutiloba according to its ripening stages. Methods and Results: The seeds were harvested from a research farm managed by the Department of Herbal Crop Research, Rural Development Administration in 2018 and were divided into six groups according to their specific gravities. In particular, we studied the effect of harvesting periods and umbel orders on seed characteristics. The results showed that the rates of germination, emergence, and early growth improved as the specific gravity of the seeds increased. In addition, the germination rates of the seeds harvested in mid July and early August were significantly higher than those harvested in the other seasons, and the seeds obtained from the first floret had the greatest mass and weight. Conclusions: In this study, we demonstrated that it is possible to improve the germination rate by appropriate selection of seeds and harvesting period both of which are closely related to seed maturity.

• Journal of Ginseng Research
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• v.20 no.1
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• pp.83-87
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• 1996

The effects of gibberilin ($GA_3$) on levels of endogenous indole-3-acetic acid (IAA) and zeatin in both fresh and stratified American ginseng (Panax quinquefolium) seeds were investigated. In our first experiment, the fresh seeds were stratified after soaked in 80 ppd $GA_3$ solution for 24 hours. We found that the IAA concentration in embryo increased by 50.7% and 82.1% respectively at the 120th day and the 188th day of stratification, and the zeatin concentration also increased by 3.8% and 51.6% respectively. In our second experiment, we treated the seeds after 134 days stratification with 80 ppm GA3 for 24 hours and then continued to stratify them. We found that the IAA concentration in embryo increased by 32.9% and 17.7% respectively at the 164th day and the 208th day of stratification while zeatin concentration increased by 22.7% and 30.6% respectively In our another experiment, we studied the effects of $GA_3$, abscislc acid (ABA) and GA, plus ABA on germination rate of seeds treated with these plant hormones during stratification. We found that when the stratified seeds whose ratio of embryo had reached 75% were treated with 80 ppm GA3 for 24 hours and then were allowed to be stratified for another 88 days, the weight and length of embryo (p < 0.05), and germination rate (p < 0.01) increased. In contrast, the 25 ppm ABA treated with for 24 hours was found to Inhibit the growth of embryo (p < 0.05) and reduce the germination rate (p < 0.05) . The experiment of combination treatment of $GA_3$ and ABA showed that $GA_3$ could relieve the inhibitory effects of the ABA on the development of the seeds.

• Journal of Korean Society of Forest Science
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• v.101 no.4
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• pp.619-625
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• 2012

This study was conducted to investigate the variation of fruit, seed and germination characteristics among populations of Serrateleaf Pearlbush (Exochorda serratifolia S. Moore) distributed in Korea. Fruits collected from 96 trees in five natural populations and their five fruit, seven seed and three germination characteristics were analyzed. In 14 characteristics except for mean germination time, there were significant differences among populations and among individuals within population. Generally, fruit and seed characteristics showed higher values among population in total variance component. Coefficients of variations in weight of fruit (27.0%), length/thickness of seed (28.1%) and germination rate (52.5%) were relatively high compared to other traits. In seed germination behaviors, germination percentage, mean germination time and germination rate showed 62.9%, 64.0 days and 0.40 ea./day, respectively. As a result of simple correlation analysis, mean germination time showed a significant positive correlation with seed thickness, germination rate showed a significant positive correlation with height of parent tree and latitude, respectively. Also, latitude showed a positive correlation with fruit weight. The populations close geographically did not show the tendency of clustering into the same group. The results of principal component analysis showed that the first for principal components (PC's) explained 63.0% of the total variation. Primary 3 principal components appeared to be major variables because of the loading contribution of 97.0%.

• Korean Journal of Ecology and Environment
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• v.48 no.1
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• pp.32-37
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• 2015

Naturalized plants are invaded through various routes and distributed throughout the nation. They are also invaded in the sand dune ecosystem and poses a threat ecological niche of indigenous sand dune plants. We studied the effects of salt stress on the plant growth to suggest the management plans of naturalized plants in the sand dune ecosystem. As a result of germination experiment according to the salt gradient, germination rate decreased as the higher concentration and tolerance range was up to 160 mM. As a result of seedling experiment according to salt gradient, mortality rate was up to 90% from 0 mM to 200 mM and 100% over 300 mM. The day of first death with different concentration was 18.5 days in 100 mM and 6 days in 800 mM since the experiment has started. In addition, the day of last death with different concentration was 29.5 days in 100 mM and 6 days in 800 mM. Therefore, two stages of management plans would be effective. The first one is to suppress the germination by salt spray over 170 mM before germination. The other one is to wither seedlings in a short period by salt spray over 600 mM.

• Plant Biotechnology Reports
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• v.4 no.2
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• pp.117-123
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• 2010

We used a flow cytometer to investigate the variations in endopolyploidy (the frequencies of nuclei with DNA contents equivalent to 4C through 16C) during the short period of the early growing stage in vigorously growing young tissues of maize seedlings. We examined different portions of the root and leaves that had been growing for 7 (day 7) and 13 (day 13) days after germination. Endoreplication showed two opposing phenomena without aging. In one case, the endopolyploidy of the first leaf was higher on day 13 than on day 7. In the latter case, endopolyploidy decreased, as clearly revealed by a comparison of the endopolyploidy of the second leaves and the 160-170 mm portion of the seminal root on days 7 and 13. Endopolyploidy was also lower in the top of the leaf. In roots, endopolyploidy was increased by the exogenous application of abscisic acid for only 1 day. The levels of endopolyploidy increased without an increase in cell size in the roots. These results showed that endoreplication occurs in actively growing and young tissue and that the variation can be induced in the short period examined.

• Korean Journal of Medicinal Crop Science
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• v.9 no.1
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• pp.68-75
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• 2001

Reasonable seedling emergence is a prerequisite for successful crop cultivation especially in medicinal crops. The study was carried out to model the pretreatment or seed treatment of Codonopsis lanceolata seeds by evaluating the treatment effects of priming, $GA_3$, drying and water imbibition after drying on their germination and then their successive seed treatment on the basis of its seedling emergence. The priming using $Ca(NO_3)_2$ and $GA_3$ treatment under their different concentrations and light quality illuminated for 12 hours a day were separately done and the two best results from priming and $GA_3$ treatments were compared to determine the better one. The drying of imbibed seeds using the above best result and water imbibition of the dried seeds were successively done to measure the rates of germination and emergence. On the greatest germination rate of the first two individual treatments, priming was obtained at $Ca(NO_3)_2$ 150 mM under blue, red light or darkness for 2 days but $GA_3$ was done at 0.1 mM under blue light imposed for 3 days. However, the result of the latter $GA_3$ treatment was better than that of priming. $GA_3$ treated seeds were best desiccated under $35^{\circ}C$ and 4 hour red light illumination. A day water imbibition immediately before sowing increased the germination rate of seeds dried after $GA_3$ treatment. Seedling emergence tested after all 3 successive treatments, $GA_3$, drying and water imbibition before sowing was greater than the two others, only $GA_3$ treatment and the combination of $GA_3$ and drying, meaning that its pretreatment of seeds or seed treatment must follow the successive procedure of the above 3 ones.

• Journal of radiological science and technology
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• v.44 no.3
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• pp.253-260
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• 2021

The purpose of this study is to measure of growth and chlorophyl in barley exposed by X-ray. Barley seed was soaked 24h duration in water, then was classified into two group; pre-seed germination group (Pre-G) or post-seed germination group (Post-G). Also, divided as control subgroup and experimental subgroup(10Gy, 20Gy, 30Gy) in each group. Experimental subgroups were exposed by X-ray using linear accelerator (Clinac IS, VERIAN, USA). Expose condition was 6 MV X-ray, SSD 100 cm, 18×10 cm, 600 MU/min. Length was measured every day for 10 days and 10th day for weight. Chlorophyl was analyzed using spectrophotometer(uv-1800, shimadzu, japan) in l0th day. Data analysis was performed using SPSS ver 22.0(Chicago, IL, USA), ANOVA test (Dunnett_T3) between control subgroup and experimental subgroup in group and Independent T-test between Pre-G and Post-G in subgroup. In Pre-G, length of barley was significantly difference between control and 30Gy in 4th day (4.3 vs. 1.5, p= 0.011). Length of 30Gy was statistical difference with control(10th day; 14.4 vs. 6.3, p < 0.01), and was not in 10Gy or 20Gy in all day. In experimental subgroup, length was shorter as increasing radiation dose. In Post-G, length of barley was not difference statistically between control and experimental subgroup in first day, but more difference between two subgroup with increasing duration after exposing. Length of experimental subgroup was shorter significantly compared with control in 10th day, and no significant difference between experimental subgroup. Density of chlorophyl was increasing with increasing radiation dose in Pre-G and Post-G. Chlorophyl density of control was lower than 30Gy; 0.26ppm in Pre-G, 0.29ppm in Post-G). Growth and chlorophyl of barley was effected by X-ray. It is expected to be used as basic data for future radiobiological research.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.85-93
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• 1984

This research was carried out to study the seed dormancy of radishes which were used for summer vegetation. The differences of dormancy of cultivars, maternal effects, the effect of full day length to mother plants, and the effects of chemical treatments for breaking the seed dormancy were considered for this study. These results sere summarized as follows; 1. The germination percentage of 7 cultlvars sown just after harvest were as follows;SP70-:0, PS11-:37.5, GJ75-:75.5, JD127-:77.5, YH85-:81.0, M55-:96.5, and JC73-:98.0%. 2. The dormany of $F_1$ seed of radish was severe when SP70-was used for mother plant. 3. Germination behavior was different by the maturity of plants grown for seed production. The dormancy of seed harvested from immature field-grown plants sown Nov. 10 was deeper than mature plants sown Mar. 22. 4. The germination ratio of tire seed of SP70-radish was increased by treatment of full day length to tire mother plant during full period of growing or since first flowering stage, while that was 0% by treatment since yellow ripening stage. 5. GA 200 ppm+thiourea 0.2% treatment was most effective for breaking of radish seed dormancy.

• Journal of Korean Society of Forest Science
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• v.100 no.2
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• pp.226-231
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• 2011

Ulmus davidiana var. japonica is a deciduous tree species used for traditional medicine. This study was conducted to investigate the variation of samara, seed, germination and growth characteristics among populations and among individuals within five natural populations of U. davidiana var. japonica distributed in Korea. The ten characteristics of samara and seed, the three germination behaviors as well as the two growth traits were studied in samaras collected from total 32 trees. Statistical analysis of all characteristics showed that there were significant differences among populations as well as among individuals within populations. In this study, the mean characteristics of this species were 13.0 mm in samara length, 9.7 mm in samara width, 1.37 in samara index, 0.015 g in samara weight, 3.07 mm in samara stalk length, 3.85 seed length, 2.66 mm in seed width, 1.46 in seed index, 1.29 mm seed thickness, 0.0062 g in seed weigh, 34.8% in germination percentage, 8.6 days in mean germination time, 3.5 ea./day in gemination rate, 37.7 cm in height and 4.90 mm in root collar diameter. Especially, coefficients of variations in samara weight, germination percentage, germination rate, height and root collar diameter were relatively high (${\geq}30.0%$) compared to other traits. There was no significant relationship between population association and geographical distribution. The results of principal component analysis for 15 characteristics showed that primary four principal components (PC's) explained 100% of the total variation. The first PC accounted for 41.8% of the variability which correlated with morphological traits, the second PC accounted for 32.9% of the variability which correlated with germination behaviors and the third PC accounted for 16.3% of the variability which correlated with growth traits.