• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.42-48
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• 2017

This study was conducted to establish the optimal condition for in vitro propagation of Disporum sessile. In the experiments with different kinds of media (MS, B5 and WPM) and explant types for shoot induction and elongation, the highest number of shoot inductions (2.5/explant) was shown when the axillary bud explants were cultured on MS medium without plant growth regulators (PGRs). The best shoot elongation (7.2 cm) was also obtained when the apical buds were cultured on MS medium. The effect of BA pulse treatments with in vitro shoots was also examined. The highest in shoot induction (2.29/explant) and elongation (7.28 cm) was observed when the shoots from axillary buds were cultured on the media without PGRs. However, it decreased with increasing duration of BA pulse-treatment. The highest rooting rate (100%) and number of root inductions (21.3/explant) were achieved with 1.0 mg/L indole-3-butyric acid (IBA) treatment, whereas no differences were observed by different shoot types. The regenerated in vitro plantlets were hardened and successfully established in soil.

• Journal of the Korean Institute of Landscape Architecture
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• v.16 no.2
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• pp.9-21
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• 1988

This study was to obtain effect of stem leading time and angles on the growing and flowering in climbing rose. The results were as follows : In the rambler type, climber type and pillar type, differences of bud size were decreased between upper ports and lower parts as leading angles were close to the horizon. And bud type was like a long-egg shape. regardless of growing type, differences of stets diameter between upper parts and lower parts were decreased when the angles were leaded horizon. In order to increase rate of shooting and flowering, regardless of leading time, rambler type was shooted in a short period and flowered evenly, from upper to lower parts of stem as leading angles were horizon. But in the case of 45$^{\circ}$, the rate of lower parts was nearly zero. In climber type, shooting and flowering was only happened to the lower parts of stem when leaded during growth stage according to leaded horizon. These phenomena are supposed that shooting and flowering rate are influenced by not only apical dominance but degree of bud growth. Meanwhile, pillar type was shooted and flowered evenly to lower parts when the stem was leaded during growth stage or not leaded completely. But in creeper type, there was no connection with the leading. Therefore, this type had better not leaded. Length of flowering stem, regardless of growing type, was equaled when leaded during growth stage according to leaded horizon.

• Journal of Forest and Environmental Science
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• v.24 no.2
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• pp.79-88
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• 2008

Twenty-eight of 44 Indian Ceropegia species are endemic and their survival is threatened. As a step towards conservation, we implied in vitro methods for the sustainable propagule production in C. hirsuta, C. lawii, C. maccannii, C. oculata and C. sahyadrica. Effects of explant, growth regulators, sucrose and photoperiod were studied. High frequency microtuber production was achieved with the seedling-apical buds, grown on MS medium containing 4-6 mg $1^{-1}$ BAP, 3-8% (w/v) sucrose, under continuous illumination. Each microtuber, when subcultured proliferated to form a cluster of secondary microtubers. Every primary and secondary microtuber bore at least one shoot-bud and a root primordium. Each tuber (formed with any of the significantly effective treatments) weighed more than 500 mg, enough to plant directly in non-sterilized soils. Microtubers could be produced and proliferated round the year. Proliferation could be solely attributed to in vitro procedures as these plants bear solitary tubers in vivo. Microtubers could be sprouted in vitro to prepare ready to pot plantlets. As, this novel method succeeded for all five species, though they belong to different eco-physiological backgrounds, we recommend its implementation in the conservation programs for a broader range of Ceropegia species, supported by other integrated strategies.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.223-227
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• 1998

The objectives of this study were to find the sprouting condition and to establish the optimum production methods of plug seedlings in yacon (Polymnia sonchifolia Poepp. & Endl.). The sprouting ratio was greatest at $30\pm 1^{\circ}C$ at 20 days after planting. Crowns with single buds were more effective than those with two or more buds for sprouting, which might be due to the apical dominance. Planting the shoots separated from crown after sprouting in the single- and double-layer polyethylene-covered greenhouses reduced seedling period with 25% and 50%, respectively. Planting the shoots after sprouting was more effective than planting the crown buds. Double-layer polyethylene-covered green-house was good for plug seedling production than open field or single-layer polyethylene-covered greenhouse. The bed soils composed of clay loam : compost or sand : compost (1:l=v:v) were more effective to produce plug seedlings than only clay loam, sand or compost. Seedlings could be produced at 30 days after planting in our studies.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.233-236
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• 2006

This study was conducted to investigate somatic embryogenesis capacity using callus derived from bud meristems in sweetpotato. Shoot apical meristem explants $(height:150{\mu}m;base:\;350{\mu}m)$were cultured on MS medium supplemented with 1 mg/L 2/4-D. Embryogenic callus were observed in five cultivars when their shoot apices were cultured on MS medium supplements with 1 mg/L 2,4-D. After 6 weeks of culture, greater than 80% of the survived explants produced embryogenic calli and the calli gave rise to somatic embryos at frequencies of 72% (Yulmi), 60% (Shinhwangmi), 78% (Geonmi), 70% (KoKei 14), 40% (Sinjami). The regenerated plants developed into whole plantlets after they were transferred onto the fresh hormon-free MS medium of 74% (Yulmi), 82% (Shinhwangmi), 86% (Geonmi), 74% (Kokei 14), 41% (Sinjami) respectively.

• FLOWER RESEARCH JOURNAL
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• v.19 no.2
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• pp.89-95
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• 2011

This study was conducted to improve commercial quality of cut spray chrysanthemums 'Charming Eye' and 'Pink Pride' bred in Korea by foliar application of daminozide, suppressing excessive elongation of peduncle caused by high temperature in greenhouse. Applications were made at two floral-bud-developmental stages and concentrations used were 0, 500, 1000, and $2000mg{\cdot}L^{-1}$. As for 'Charming Eye', cut flower length, peduncle diameter, stem diameter, flower bud diameter, and the number of flower buds did not show any significant difference among all treatments including control. However, the suppressing effect of peduncle elongation, widening angle of flower cluster arrangement on apical part, and increasing parallel flower buds in stage I showed better than those in stage II regardless of daminozide concentration. As for 'Pink Pride', cut flower length, peduncle diameter, and stem diameter did not show any significant difference among all treatments including control but angle of flower cluster on apical part increased compared to control as daminozide was sprayed at stage I and II except $2,000mg{\cdot}L^{-1}$ daminozide-sprayed at stage II. The number of flower buds and flower bud diameter showed the greatest increment through $1,000mg{\cdot}L^{-1}$ daminozide-sprayed at stage I and did the least values as sprayed with $2,000mg{\cdot}L^{-1}$ daminozide at stage II. Daminozide also gradually reduced peduncle length in a concentration-dependant manner but elongation of peduncle foliar-sprayed at stage I showed the more suppressing effect than that at stage II. Increasing the number of parallel flower buds showed the best results when sprayed with $2,000mg{\cdot}L^{-1}$ at stage I. In conclusion, we recommended that foliar spraying with $500-1,000mg{\cdot}L^{-1}$ daminozide at stage I and foliar spraying with $1,000-2,000mg{\cdot}L^{-1}$ daminozide at stage I improved cut flower quality of 'Channing Eye' and 'Pink Pride', respectively.

• Journal of Plant Biotechnology
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• v.41 no.2
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• pp.100-106
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• 2014

In order to develop an efficient in vitro micropropagation technique for a rare plant species, Astragalus membranaceus Bunge var. alpinus N., shoot proliferation and in vitro or in vivo rootings were conducted and hyperhydrated leaf generated from cultures was histologically observed. During shoot induction, no distinct effect on multiple shoot induction was found between BA and kinetin treatment. BA enhanced the number of internodes, whereas kinetin stimulated shoot elongation. Hyperhydrated leaf composed of bigger cells and retarded palisade parenchyma and showed irregular cell arrangement compared to normal leaf. Especially starch content in hyperhydrated leaf was significantly reduced. The best rooting rate was achieved by B5 medium among three different medium (B5, MS and WPM) and 0.1mg/L IBA treatment induced the highest rooting ratio (80%). No statistical difference was induced by explant types (apical bud or axillary bud) in terms of rooting ratio. In vivo cutting induced rooting rate up to 65% by 0.5% IBA/Talc powder treatment. Although in vivo rooting rate was less efficient compared to in vitro rooting, better survival rate was observed after soil acclimatization. Present study suggested that above micropropagation techniques can be used for rapid multiplication as well as in vitro or in vivo conservation of the species.

• FLOWER RESEARCH JOURNAL
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• v.17 no.2
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• pp.121-127
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• 2009

This study was conducted to improve commercial quality of a cut spray chrysanthemum 'Gama' bred in Korea by foliar application of daminozide (DMZ), suppressing excessive elongation of peduncle caused by high temperature in summer season production. Applications were made at three floral bud developmental stages (I, II, and III), and concentrations used were 0, 500, 1000, and $2000mg{\cdot}L^{-1}$. Both cut flower length and peduncle length showed the greatest suppression of elongation by DMZ treatments at stage II. DMZ also gradually reduced values of those in a concentration-dependant manner. Stem thickness and flower diameter reduced compared to control as DMZ was sprayed at later stage and those two characteristics decreased in a concentration-dependant manner. The number of paralleled flowers neighboring apical part of whole plant showed the best results at stage I and II. As for DMZ concentration, those increased effectively at $500-1,000mg{\cdot}L^{-1}$. Among all combinations, $1,000mg{\cdot}L^{-1}$ DMZ at stage II recorded the most paralleled flowers and showed 24.2% increment as compared to control. The number of fully expanded flowers and total floral buds also showed the highest values using $1,000mg{\cdot}L^{-1}$ DMZ at stage II than the other treatments. In cut spray chrysanthemum cultivar 'Gama' bred in Korea, foliar-spraying with $1,000mg{\cdot}L^{-1}$ DMZ at stage II most effectively suppressed excessive peduncle elongation, parallelled flower cluster arrangement, and increased the number of flowers in summer. However, this combination affected negatively the other commercial qualities, reducing cut flower length, stem thickness, and flower diameter. Therefore, we recommended that foliar-spraying stage and DMZ concentration was stage I and $1,000mg{\cdot}L^{-1}$, respectively, in a practical culture for 'Gama'.

• FLOWER RESEARCH JOURNAL
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• v.18 no.4
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• pp.231-237
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• 2010

This study was conducted to improve commercial quality of a cut spray chrysanthemum 'Ilweol' bred in Korea by foliar application of daminozide, suppressing excessive elongation of peduncle caused by high temperature in summer season production. Applications were made at three floral bud developmental stage (I, II, and III), and concentrations used were 0, 500, 1000, and $2000mg{\cdot}L^{-1}$. Cut flower length and peduncle length showed the greatest repression of elongation through daminozide treatments at stage III and stage II, respectively. Daminozide also gradually reduced values of those in a concentration-dependant manner. Flower diameter increased compared to control as daminozide was sprayed at later stage but decreased in daminozide concentration-dependant manner. Angle of flower cluster on apical part of whole plant showed the best results when sprayed with $2,000mg{\cdot}L^{-1}$ at stage III. Among all combinations, $2,000mg{\cdot}L^{-1}$ daminozide at stage II recorded the highest angle of flower cluster and showed 31.3% increment as compared to control. The number of fully expanded flowers showed the highest values using $2,000mg{\cdot}L^{-1}$ daminozide at stage III than the other treatments and total floral buds also showed the highest values using $2,000mg{\cdot}L^{-1}$ daminozide at stage I than the other treatments. In cut spray chrysanthemum cultivar 'Ilweol' bred in Korea, foliar-applying with $2,000mg{\cdot}L^{-1}$ at stage III most effectively suppressed excessive peduncle elongation, angle of flower cluster, and increased the number of flowers in summer. However, this combination affected negatively the other commercial qualities, reducing cut flower length and flower diameter. Therefore, we recommended that foliar application stage and daminozide concentration was stage III and $500mg{\cdot}L^{-1}$, respectively, in a practical culture and cut flower quality for 'Ilweol'.

• Journal of Plant Biotechnology
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• v.49 no.1
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• pp.82-89
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• 2022

In vitro techniques were developed for propagating Vaccinium oldhamii using shoots with apical buds. Explants having an apical bud were cultured on Murashige and Skoog (MS) medium supplemented with 1.0, 2.0, and 5.0 mg/L of each zeatin, thidiazuron, 6-benzylaminopurine (BA), and 6-(γ,γ-dimethylallylamino)purine (2-iP) in order to induce multiple shoots. Among the tested treatments, the 2.0 mg/L of 2-iP proved to be most suited for the multiplication and growth of shoots; the multiple shoot induction rate was 100.0%, the average number of shoots was 7.4 per explant, and the average shoot length was 51.7 mm. The in vitro elongated shoots were rooted on half-strength MS medium containing various concentrations of indole-3-butyric acid (IBA) and 1-naphthaleneacetic acid (NAA). However, overall callus overgrowth was observed in all treatments and resulted in necrosis and abnormal shoot growth in root formation. A low concentration (0.5 mg/L) of IBA was appropriate for normal root development and the in vitro rooting rate was 30%. Ex vitro treatments on root formation using various concentrations of IBA with Talc powder and two types of rooting substrates (Flexi-Plugs or Horticultural soil) were examined. The ex vitro rooting rate (80%) and length of roots (32.9 mm) were obtained when the cut ends of the shoots were treated with 1.0 mg/L IBA and cultivated in Horticultural soil for 2 months. These findings suggest that ex vitro rooting is the more effective method for improving root formation in Vaccinium oldhamii than in vitro rooting.