• Korean Journal of Plant Resources
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• v.33 no.2
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• pp.86-92
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• 2020

This study was conducted to analyze ripening characteristics of the seed according to days after flowering. The seeds were harvested on land located in the Department of Herbal Crop Research in Rural Development Administration in 2019. Seed weight and germination rate were investigated according to days after flowering and the embryo:seed ratio was examined during the fruiting process. The results showed that the weight increased significantly by the days after flowering at each inflorescence and the seed began to germinate at different time. Further, given the embryo:seed ratio, we found that embryo continue to grow in the seed. Because Angelica acutiloba (Siebold & Zucc.) Kitagawa bloom in various inflorescences, the stage of embryonic development of the seeds can affect the germination of seed. Based on our results, the key seed harvest period for good seed is 50 to 70 days after flowering.

• Korean Journal of Medicinal Crop Science
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• v.24 no.3
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• pp.207-213
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• 2016

Background: This study aimed to investigate the flowering and fruits formation characteristics of Korean Panax ginseng varieties. The results will provide basic data for ginseng seed production and breeding program. Methods and Results: The characteristics investigated included flowering date, seed setting rate, seed type and seed production. The ginseng variety Chungsun had the earliest emergency and flowering dates, whereas Sunhyang showed late emergence and flowering dates. The emergence date of Chunpoong was not later than that of the other varieties, but the flowering date was delayed. The seed setting rate was 64.6%, 75.8%, 78.5% and 74.4% for three, four, five and six-year-old varieties, respectively. The ratio of double seed (RD) for Sunhyang and Chungsun were higher than those for the others, whereas the RD for Chunpoong was the lowest. Yunpoong and Sunone had many stems per plant and a high seed production rate. Seed production was 21.7, 67.7, 74.4 and 89.0kg/10 a in three, four, five and six-year-old varieties, respectively. Conclusions: The emergence date ranged from April 15 to 25, and the flowering date was from May 10 to the 19 for the new ginseng varieties. The average seed multiplication of the ginseng varieties was about 8.5 and 21.1 times a year for varieties in which, seed-production occurs once a year for over four years and four times over six years, respectively.

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.343-347
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• 2013

BACKGROUND: Control of alternate bearing satsuma mandarin in Jeju is very important to maintain the optimum price of fruit and get the sustainable income of farmers. Unlike orange, Satsuma mandarin is well known to sensitive on alternate bearing. We carried out the experiment to know the effect of foliar application of $GA_3$ on the flowering and fruit quality of satsuma mandarin (C. unshiu Marc. cv. Miyagawa). METHODS AND RESULTS: To experiment, the treatments consist of control, different concentration of $GA_3$ (25, 50 and 100 mg/L), machine oil emulsion 100 times and mixture of various concentration of $GA_3$ (25 and 50 mg/L) with machine oil emulsion 100 times which it was applied on 15 year-old Miyagawa satsuma mandarin at December 29, 2011. Foliar application of $GA_3$ in winter reduced the flowering of satsuma mandarin. Flower-leaf ratio was significantly reduced at 100 mg/L $GA_3$, while no differences observed in low concentration of $GA_3$ (25 and 50 mg/L). However, it was significantly decreased to 0.19 in application of $GA_3$ 25 and 50 mg/L with machine oil emulsion 100 times mixture. Number of leaves per fruit was significantly increased as foliar application of $GA_3$ also it reduced the fruits remarkably. Soluble solid contents and Hunter's a of peel color ratio showed no difference among $GA_3$ single treatments, but it was reduced in $GA_3$ 25 and 50 mg/L with machine oil emulsion 100 times mixtures significantly. From the results, it has been found that higher $GA_3$ concentration can reduce the number of flowers on the alternate bearing of satsuma mandarin. However, it was found that lower concentration of $GA_3$ with machine oil emulsion mixture 100 times can reduce flowering. CONCLUSION(S): The foliar application of $GA_3$ (100 mg/L) can alleviate alternate beraring. Also, mixture of lower concentration of $GA_3$ with machine oil emulsion 100 times can retard flowering more significantly while it needs further confirmation.

• Journal of Plant Biotechnology
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• v.1 no.2
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• pp.109-115
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• 1999

A linkage map of Capsicum annuum L. was constructed by random amplified polymorphic DNA (RAPD) markers followed in a backcross population of an intraspecific cross between cultivars HDA210 and Yatsufusa. A total of 420 random primers were tested and 311 polymorphic bands were generated by 158 random primers. Among them, 86 Yatsufusa specific bands generated by 52 primers were examined for mapping. Most bands except three segregated in Mendelian fashion fitting the expected 1:1 ratio. The total length of the map was 533 cM distributed in 15 linkage groups. The map distance between adjacent markers ranged 0 to 32.8 cM, with an average distance of 9.1 cM (63 markers). Some markers were clustered and this may be due to the amplification of a repetitive sequence by the RAPDs. Primer pairs for a sequence characterized amplified region (SCAR) were developed and the segregation scores by the SCAR primers were in accordance with the RAPD data. Two QTL markers for number of axillary shoots and for early flowering were developed. One QTL for early flowering located in the linkage group 3 and explained 61 "io of the phenotypic variation. The other QTL for the number of axillary shoots located in the linkage group 4 explained 55 % of the phenotypic variation.tion.

• Journal of the Korean Society of Food Culture
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• v.19 no.6
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• pp.598-604
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• 2004

This was aim to study the changes of components by different parts and maturity of tomato. We found that orally fed tomatine which induced a significant reduction in cholesterol in hamster in contrast to potato glycoalkaloids, the safety of tomatine was supported by our observation that pickled green tomatoes consumed widely in many countries has a high tomatine content. The tomatoes harvested during the first stage(10 days after flowering) contained tomatine $6333.49{\mu}g\;per\;100g$ and dohydrotomatine and ${\alpha}$-tomatine in a ratio of about 1:13.8. The tomatine content then decreased by about 85% during stage 2(20 days after flowering) an dehydrotomatine contene dropped to a value near zero during stage 3, 4 It on the tomatine content dropped to a value near zero during the final stage(50 days after flowering). With respect to health benefits at all stages of maturity, unripe tomato contain chlorophyll and ${\alpha}$-tomatine should consumed.

• Korean Journal of Plant Resources
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• v.34 no.5
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• pp.462-469
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• 2021

Maesa japonica (Thunb.) Moritzi & Zoll. is a rare evergreen shrub that occurs in west Gotjawal, Jeju island, Korea. This study was conducted to investigate effects of an artificial shading on flowering and growth characteristics of M. japonica seedlings. The level of shading had been set to be 35%, 55% and 75% using shading net. The stage of flowering and flowering ratio, seedling height, the number of leaves and stems, leaf area were measured. Flowering timings were delayed by shading. The number of flowering seedlings per plot and inflorescences per seedling were the most in 55% shading level. Tendency of decreased seedling height with increased shading level was shown. The number of leaves and stems were the fewest values in 75% shading level. The increased biomass with decreased shading level was statistically significant. Aboveground and underground biomass were 2.1 and 1.7 times higher in shading 35% than in shading 75%, respectively. Meanwhile, all seedlings in non-shading plots were dead in winter. Such might be speculated as results of the light stress. As a result, we conclude that M. japonica vitally demands the shading for growth and the optimal shading levels for growth and flowering are 35% and 55%, respectively.

• Journal of Ginseng Research
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• v.25 no.1
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• pp.41-44
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• 2001

This study aimed to identify the flowering and fruiting characteristics of 2 varieties (Chunpoong and Yunpoong), 3 superior lines (KG103, KG104, KG105) and Hwangsookjong selected for development of varieties of Panax ginseng C.A. Meyer. The flowering date of Yunpoong and KG103 line showed earlier than any other lines or variety. Fertility ratio of KG104 was higher than others and the lowest with KG103 showing over 60% in all varieties and lines tested. On the fruiting type of lines, ratio of single ovary type of Chunpoong and KG105 was higher than double ovary type while Yunpoong, KG104 and Hwangsookjong were formed more double ovary type. Seed yield of KG104 per stem was the highest but Yunpoong showed the highest per kan (90 ${\times}$ 180 cm). Seed size of KG103 was the biggest among the lines tested, meanwhile that of Chunpoong and Hwangsookjong were smaller.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.91-95
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• 2001

Propagules grown at different in vitro culture conditions such as heterotrophic, mixotrophic and photoautotrophic conditions were investigated for growth, total photosynthesis ratio and flowering. Survival rate of propagules after transplanting was higher in photoautotrophic propagules than in the heterotrophic and mixotrophic ones. Total photosynthesis was higher plantlets growth in photoautotrophic (154 mg$CO_2$.mgDW$^{-1}$ h$^{-2}$ ) those grown than in mixotrphpic (148 mg$CO_2$.mgDW$^{-1}$ h$^{-2}$ ) and heterotrophic (102 mg$CO_2$.mgDW$^{-1}$ h$^{-2}$ ) 30 days after transplanting into fields. Day to flowering of the plant cultured in photoautotrophic condition was shortened by 7~10 days than those of heterotrophic and mixotrophic ones. Length of the petiole, number of leaves, leaf area and chlorophyll content were also increased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.304-312
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• 2023

Plant breeding is a time-consuming process, mainly due to the limited annual generational advancement. A speed breeding system, using LED light sources, has been applied to accelerate generational progression in various crops. However, detailed protocols applicable to soybeans are still insufficient. In this study, we report the optimized protocols for a speed breeding system comprising 12 soybean varieties with various maturity ecotypes. We investigated the effects of two light qualities (RGB ratio), three levels of light intensity (PPFD), and two soil conditions on the flowering time and development of soybeans. Our results showed that an increase in the red wavelength of the light spectrum led to a delay in flowering time. Furthermore, as light intensity increased, flowering time, average internode length, and plant height decreased, while the number of nodes, branches, and pods increased. When compared to agronomic soil, horticultural soil resulted in an increase of more than 50% in the number of nodes, branches, and pods. Consequently, the optimal conditions were determined as follows: a 10-hour short-day photoperiod, an equal RGB ratio (1:1:1), light intensity exceeding 1,300 PPFD, and the use of horticultural soil. Under these conditions, the average flowering time was found to be 27.3±2.48 days, with an average seed yield of 7.9±2.67. Thus, the speed breeding systems reduced the flowering time by more than 40 days, compared to the average flowering time of Korean soybean resources (approximately 70 days). By using a controlled growth chamber that is unaffected by external environmental conditions, up to 6 generations can be achieved per year. The use of LED illumination and streamlined facilities further contributes to cost savings. This study highlights the substantial potential of integrating modern crop breeding techniques, such as digital breeding and genetic editing, with generational shortening systems to accelerate crop improvement.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.2
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• pp.39-46
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• 1983

In order to obtain the basic information for the most successful breeding of Burley tobacco, these studies were performed on the correlations among agronomic characters and on the heterosis and combining ability in $F_1$ generation. Heterosis ratio was highly variable in different $F_1$ combinations. Positive heterosis was observed in all characters except days to flowering and yield showed the highest heterosis ratio. As the results of analysis of dialled table, the general combining ability (GCA) in all characters was shown to be significant . All characters except the number of leaves in the specific combining ability (SCA) were significant, Variety, L8, contributed negative GCA for all characters. Burley 21, ky 10 and ky 14 contributed negative GCA for leaf width, quality and yield, respectively. Hybrid of ky 10 x ky 14 showed negative SCA and hybrids of ky I0x L8 and ky 14 x L8 showed positive SCA for all characters. There were significant correlations between yield and number of leaves, leaf length, leaf width or leaf area. Correlation between yield and days to flowering was non- significant .