• Korean Journal of Medicinal Crop Science
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• v.16 no.1
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• pp.39-43
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• 2008

The effect of colchicine treatment on the agronomic performance and polyploid formation of Bupleurum falcatum using flow cytometry technique was investigated. The roots of 4-leaf stage plants were treated with colchicine (0.5%) for 3, 6, 12, and 24 hours and then transplanted in the field. Agronomic characters (survival rate, plant height, chlorophyll content, bolting rate) were recorded at 4 weeks and 6 months after transplanting while flow cytometry technique was conducted for determination of polyploid formation. Flow cytometry technique revealed polyploid nuclear DNA formation in colchicine treated plants. The highest number of polyploids was obtained at the shortest colchicine treatment time indicating an inverse relationship between colchicine treatment time and polyploid formation. Results also showed that survival and bolting rates were inversely related with the treatment time while plant height and chlorophyll were not significantly affected by the treatment. This study showed a convenient method for determination of colchicine-induced polyploid in B. falcatum and its superior agronomic performance at shorter treatment time.

• Journal of the Korea institute for structural maintenance and inspection
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• v.2 no.2
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• pp.202-208
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• 1998

To investigae the effect of anchorage type of carbon fiber sheet (CFS) on flexural behavior of RC beams, the loading test of RC beams reinforced with CFS was conducted in variable of anchorage Type such as bolting anchorage and U type anchorage using CFS. This study can be summarized as follows ; It is confirmed experimentally that the bolting anchorage and U type anchorage with CFS is very effective to delay the bond failure and prevent the peeling of CFS. Also, the anchorage type applied with this study is very effective to improve the ductility compared with the improving of maximum flexural strength of RC beams. It is believed that the anchorage type used this study must secure the ductile capacity of above 3 for the flexural strengthening of RC beams. In the future, it is required to obtain the data about anchorage type of CFS for utilization of field work as well as investigate the ductile capacity of conventional study of anchorage type

• Korean Journal of Medicinal Crop Science
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• v.10 no.5
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• pp.419-422
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• 2002

Korean angelica(Angelica gigas Nakai), a oriental medicinal plants is important and in great demand in Korea. This crop is a biennial which is to die after flower, so as could not harvest the root. A new variety 'Anpung' was developed from the selection of the local collecting population by medicinal crop team at NCES in 2001. This showed stable bolting during its cropping year and have high quality and yield potential. The color is greenish purple in stem and red purple in flower. It was longer in plant height and root length, thicker in root diameter, more leave and latheral roots comparing with the check variety 'Manchu'. The dry root was 72 g/plant showing heavier than check variety of 65 g/plant. It showed such low bolting rate as 0.5%, on the other hand 49.3% in landrace when it cultured by transplanting with heating nursery seedlings, and $0{\sim}15%$ with field nursery seedlings. The dry root yield of the variety was averaged 3,630 kg/ha out yielding the check variety by 11% at the three regional yield test from 1999 to 2001. Finally, 'Anpung' showed higher content of extracts up to 46.3% in 'Anpung' and 45% in check variety, decursin and decursinol contents was 3.48% and 2.79%, showing slightly higher than check variety.

• Korean Journal of Medicinal Crop Science
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• v.6 no.2
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• pp.160-164
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• 1998

Angelica gigas has been a major medicinal crop in Korea for a long time. This study was to determine optimum seeding time and bolting response by shifting seeding time between November 10, 1993, and August 10, 1994 using promising line, Suwon 2. Days to emergence were similar among seeding times from April 10 to August 10 in Suwon. Seedling duration was shortened 92 days when seeded on July 10 compared with the conventional seeding time of April 10. Productivity of seedling ranging from 0.31 to 0.70cm in diameter was highest of 730 plants per $m^2$ in July 10 seeding. When seeded in July 10, bolting rate was 2.4 percent as compared with 2.6 percent in conventional seeding (April 10). The optimum seeding time was July 10. Seedling quality, survival rate after planting in field, and root yield were greatly influenced by seeding time.

• Korean Journal of Medicinal Crop Science
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• v.8 no.3
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• pp.283-289
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• 2000

This study was to determine optimal sizeof root top using Suwon 2 selected from the Jinbu local population though pure line selection and five root head diameters of $0.11{\sim}0.30,\;0.31{\sim}0.50,\;0.51{\sim}0.70,\;0.71{\sim}0.90\;and\;0.91{\sim}1.10cm$. Emergence rate, characteristics of top, and root were increased with increasing diameterof seedling root. In the group of root head diameter from 0.51cm to 0.70cm, bolting rate was the lowest being less than 3.3% and root yield was the highest being more than 300kg/l0a. Bolting rate was positively correlated with plant height while showed negatively correlated with root yield. The study showed that the optimum of root head diameter raised seedlings in the open field appeared to be from 0.31 to 0.70cm.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.579-582
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• 2009

A new red leaf lettuce (Lactuca sativa L.) cultivar, "Mihong" which has late bolting and deep red leaf color was developed from a cross of "Danhongongchukmyeon" (deep red but early bolting and low yield) and "Hajicheongchukmyeon" (late bolting and high yield). The selection and breeding of advanced lines were done by pedigree method during 2000-2006. The advanced lines were evaluated for yield and adaptability in Korea (Gangwon, Kyunggi, Chungbuk, Kyungnam, Jeonnam, Jeonbuk, and Jeju) from 2007 to 2008. The "Mihong" has gray seed color, traverse elliptic leaves and deep red color. Compared to "Dukseomjeokchukmyeon", marketable yield of "Mihong" was higher by 2% (at 291 g per plant) as a 17.3 ton/ha, but with particularly improved good expression of deep red leaf color in high temperature cultivation in the field. The shelf-life of "Mihong" was three weeks longer than "Dukseomjeokchukmyeon" at $4^{\circ}C$. The amount of anthocyanin content of "Mihong" were higher than with "Dukseomjeokchukmyeon" at 28.9 mg/100 g. Especially the degree of leaf hardness in "Mihong" showed $26.9kg/cm^2$ compared to "Dukseomjeokchukmyeon". therefore, its taste is better, more crispy, and sweeter than "Dukseomjeokchukmyeon" This new cultivar "Mihong" can be cultivated in all year around even if summer time cultivation.

• Korean Journal of Medicinal Crop Science
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• v.2 no.2
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• pp.146-148
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• 1994

The most important subject in cultivation of A. gigas NAKAI would be how to decrease the bolting rate. Belcause the decrease and poor of the yields and quality is imevitable in such field where the bolting rate is high. This study was carried out to investigate the time of flower-bud differentiation as a part of improvements of cultivation method. Shoot apex was fixed in Farmer's solution(ETOH 3:Acetic acid 1), thin paraffin ribbon was made, and the tissue was stained by Safranin solution. Differentiation time of flower-bud in A. gigas differed greatly from individuals by the seedling size, generally begun from middle of May to late of June, it was time that two leaves spread. In this results, Photoperiocid types of A. gigas NAKAI were regarded as LI type or LS type of dull-photosensitivity.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.650-656
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• 2012

The aims of the experiment, conducted over three years in the Central Europe field conditions, were (1) to investigate the effect of growing period (plantings in the middle and at the end of August: $1^{st}$ and $2^{nd}$ term, respectively) on yield and chemical composition of the non-heading Chinese cabbage (Brassica rapa var. chinensis) cultivars 'Taisai', 'Pak Choy White', and 'Green Fortune', and (2) to develop regression models to evaluate the changes in crop yields as a function of weather conditions. A highest marketable yield was obtained from 'Taisai' (65.71 and 77.20 $t{\cdot}ha^{-1}$), especially in the $2^{nd}$ term of production. Low yield, observed for 'Pak Choy White' was due to its premature bolting. Almost 39% ($1^{st}$ term) and 70% ($2^{nd}$ term) of plants of this cultivar formed inflorescence shoots before harvest. The highest dry matter level was observed in the leaf petioles of 'Taisai', while 'Green Fortune' was the most abundant of carotenoids and L-ascorbic acid. The content of soluble sugars was the lowest for 'Pak Choy White'. In a phase of harvest maturity, more of the analyzed constituents were gathered by plants from earlier plantings, and differences were as follows: 4.7% (dry matter), 26.3% (carotenoids) and 22.1% (L-ascorbic acid), in comparison to $2^{nd}$ term of production. Significant increase of soluble sugars level was observed for plants from later harvest. The regression model for marketable yield of Chinese cabbage cultivar 'Taisai' as a function of maximum air temperature can predict the yield with accuracy 68%. The models for yield or bolting of 'Pak Choy White', based on extreme air temperatures and sunshine duration, were more precise (98%). It should be pointed out that Taisai could be recommended for later growing period in Central Europe conditions with regard to maximum yield potential. 'Green Fortune' was notable for its uniform yielding. To obtained plants of higher nutritional value, earlier time of cultivation should be suggested. Described models can be successfully applied for an approximate simulation of Chinese cabbage yielding.

• Korean Journal of Plant Resources
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• v.29 no.5
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• pp.625-629
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• 2016

A new Gomchwi cultivar ‘Gommany’ was bred by crossing between Gomchwi (Ligularia fischeri (Ledeb.) Turcz.) and Handaeri-gomchwi (Ligularia fischeri var. spiciformis Nakai). The selection and investigation of growth and yield characteristics were conducted from 2006 to 2011 in field and greenhouse of Highland Agriculture Research Institute, NICS, Rural Development Administration. The color of petiole ear was purple. Petiole trichome existed, but light of leaf back did not. Density of leaf vein was 5 degree in a newly developed cultivar ‘Gommany’. Plant height, leaf length, leaf width and petiole length were 47.7, 16.3, 21.2, and 31.4 ㎝, respectively in the 3 year of growth characteristics. Plant size was also higher than that of ‘Gondalbi’. Bolting and flowering time were Aug. 5 and Sept. 10, respectively. In contrast, Bolting time of ‘Gondalbi’ showed 25 days quite earlier bolting time compared to ‘Gommany’, Which led to earlier flowering time. ‘Gommany’ showed higher number of leaves (138) per plant compared to ‘Gondalbi’ (130). Furthermore, yield was 97% higher in ‘Gommany’ (1,575 g/plant) than in ‘Gondalbi’ (798 g/plant). ‘Gommany’ showed higher leaf thickness (0.69㎜) than ‘Gonalbi’ (0.46 ㎜), and consequently showed more hardness in leaf characteristics (24.3 ㎏/㎠) compared to ‘Gondalbi’ (23.0㎏/㎠). ‘Gommany’ showed higher resistance in the susceptibility of powdery mildew compared to ‘Gondalbi’. ‘Gommany’ cultivar was registered as a novel variety with number 90 in The Minister of the Korea Forest Service on December 2015.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.1
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• pp.58-65
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• 1993

The purpose of this study is to determine the evolution of carbon and nitrogen concentrations in relation to dry matter and crude protein accumulation in the leaves of forage rape(Brassica napus Subsp. oleifera, CV. Swiss) during the growth period. Field-grown plants were sampled at intervals throughout fall, winter, early and late spring. During over-wintering period(from Nov. 7 1991 to Feb. 4 1992), the carbon concentration in the leaves increased from 382 mg to 435 mg g DM$^{-1}$ , while the concentrations of nitrogen and crude protein significantly decreased. There was little accumulation of fresh and dry matter in the leaves. On early spring growth from 4 Feb. to 30 Mar. marked carbon loss 37 mg. day$^{-1}$ and slight nitrogen accumulation occurred with the increase of fresh weight in the leaves. From spring growth to bolting stage(from 31 Mar. to 16 Apr.) the greatest accumulation of fresh and dry matter was observed and carbon and crude protein concentrations increased with a linear manner. After bolting stage the concentrations of carbon, nitrogen, hydrogen and crude protein in the leaves significantly decreased until late blooming stage, and the decreasing rate was prominent in nitrogen (45.7%) and crude protein(46%). From the results above it is recommended that fertilizer will be applied before early spring growth, and that optimal utilization period is a bolting stage. For the serious modification of the internal C/N balance during the overwintering period.