• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.1
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• pp.10-17
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• 1987

In order to investigate the effects of growth regulators on the formation of capsaicinoids in callus of Capsicum annuum L. tissues were cultured in the Linsmaier and Skoog RM 1964 medium containing various growth regulators. Production of capsaicinoids during culture was monitored by gas chromatography. In the presence of $10^{-6}M$ of 2,4-D and kinetin in the medium, $1182{\mu}g$ of capsaicinoids were formed per 100g dry wt. of tissue, of which was greater than with any of three other growth regulators. IAA, NAA, and kinetin of same concentrations had 65%, 38%, 68% effect of 2.4-D in capsaicinoids formation, respectively. Production of capsaicinoids increased gradually in the presence of 2,4-B as culture period was proceeded. Of phenylpropanoids formed, cinnamic acid and coumaric acid were not significantly different in their levels, although growth regulators were varied. On the other hand, caffeic acid and ferulic acid formation were highest in the presence of 2,4-D. Effects of kinetin and IAA were about 70 percent of that of 2,4-D, whereas NAA had only about 30 percent effect. Phenylalanine ammonia-lyase activity in cultured tissue was increased during the periods; 52, 81, and 209 n moles of cinnamic acid per g fresh wt. were formed after 5, 15, and 25 days of culture, respectively.

• Molecules and Cells
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• v.39 no.8
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• pp.587-593
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• 2016

As sessile organisms, plants must be able to adapt to the environment. Plants respond to the environment by adjusting their growth and development, which is mediated by sophisticated signaling networks that integrate multiple environmental and endogenous signals. Recently, increasing evidence has shown that a bHLH transcription factor PIF4 plays a major role in the multiple signal integration for plant growth regulation. PIF4 is a positive regulator in cell elongation and its activity is regulated by various environmental signals, including light and temperature, and hormonal signals, including auxin, gibberellic acid and brassinosteroid, both transcriptionally and post-translationally. Moreover, recent studies have shown that the circadian clock and metabolic status regulate endogenous PIF4 level. The PIF4 transcription factor cooperatively regulates the target genes involved in cell elongation with hormone-regulated transcription factors. Therefore, PIF4 is a key integrator of multiple signaling pathways, which optimizes growth in the environment. This review will discuss our current understanding of the PIF4-mediated signaling networks that control plant growth.

• Journal of Plant Biotechnology
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• v.6 no.2
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• pp.97-102
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• 2004

This study was carried out to establish The regeneration of healthy seedlings from the nodal segment culture of Chinese yam (Dioscorea opposita cv. Danma), cultivated in Korea. Different explants such as leaves, petioles, roots and nodal pieces, excised from the in vitro grown seedlings of Chinese yam, were cultured on MS medium supplemented with various combinations of growth regulators. All the growth regulators used induced plantlet regeneration from the nodal segments at a high frequency, while there was no induction of shoot or callus from leaf, petiole or root tissues. The medium supplemented with 0.01mg/L NAA, 0.5mg/L BA, 0.5-1.0mg/L kinetin and without plant growth regulator was effective for shoot development of buds from the nodal segment culture. The concentration of BA and NAA was an important factor in the bud induction of buds from the nodal segments of Chinese yam. Nodal segments cultured on the medium containing 1.0mg/L NAA and 0.5-1.0mg/L BA gave the best response to bud formation. The addition of GA$_3$ to the culture medium suppressed shoot induction and growth, while it increased microtuber formation. The shoot growth and microtuber formation were also affected by medium strength and solidity. The MS basal medium containing 1 g/L gelrite was suitable for microtuber formation from the nodal segment of Chinese yam.

• Korean Journal of Soil Science and Fertilizer
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• v.42
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• pp.153-177
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• 2009

• Journal of Forest and Environmental Science
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• v.30 no.2
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• pp.218-225
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• 2014

Studies were carried out to standardize and develop a suitable macro-propagation technology for large scale production of superior clonal stock through stem cuttings in Commiphora wightii Arnott (Bhandari), a data deficient medicinal plant of arid region. For the purpose, three experiments were conducted. The first experiment was tried to elucidate the impact of various cutting diameters (0.50-0.75 cm, 0.75-1.00 cm, 1.00-1.50 cm, and >1.50 cm) in combination with varying growing conditions (sunlight, shade house and mist chamber) on shoot sprouting and rooting without using exogenous plant growth regulators. Cutting diameter (size 0.75-1.00 cm) in mist chamber has shown maximum sprouting (90.00%) and rooting (73.33%), primary root (6.67) and secondary root (16.67) followed by 1.00-1.51 cm in mist chamber. Minimum sprouting (40.00%), rooting (33.33%), number of shoot (1.33), primary root (1.00) and number of secondary root (1.00) was recorded in cutting diameter (size >1.50 cm) in sunlight. Second experiment was performed to find out optimum growth regulator concentration of rooting hormone (100, 200, 500 and 1000 ppm) of Indole-3-acetic acid (IAA) and Indole-3-butyric Acid (IBA) on adventitious root formation on cuttings diameter (size 0.25-0.50 cm) in comparison to control. Maximum rooting percentage (93.33%) was recorded in 200 ppm followed by 500 ppm (86.66%) of IBA as compared to control, which showed only 60 per cent sprouting. Third experiment was performed with newly formed juvenile micro-cuttings treated with varying concentrations of IAA and IBA. The juvenile cuttings (size 6-10 cm, basal dia <0.25 cm) were selected as micro-cuttings. The cuttings treated with IBA (500 ppm) showed 64.30% rooting as compared to other treatments. Results of above experiments indicate that cuttings (size 0.75-1.00 cm dia) may be developed in mist chamber for better performance. While using heavier cuttings, no growth promoting hormones is required however; growth regulator 200 ppm concentration of IBA rooting hormone was observed optimum for promoting macro-propagation in stem cuttings of lower diameter class (0.25-0.50 cm).

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.2
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• pp.1-11
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• 2004

The purpose of this study was to determine usability as potted flowers and garden plants by controlled plant height using growth retardants. There was no significant difference on the dwarfing effect according to the degree of exposure the sun, but growth was well under full exposure to the sun. The plant height was decreased by application of Cycocel (CCC), Bonzi (paclobutrzol), Ancymidol, and Uniconazole compared to the control group, and treatment of Bonzi $5mg{\cdot}L^{-1}$ was most dwarfing effect for both full sun exposure or 70% controlled shading condition. No consistent different was found in stem diameter, leaf color change, the content of chlorophyll and anthocyanin when the concentration of plant growth retardants was altered. These factors were affected only by light intensity. In comparison to the results of the control group, leaf length, leaf width, plant width and petiole length were all reduced by the application of growth retardants.

• Journal of Plant Biotechnology
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• v.34 no.4
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• pp.293-298
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• 2007

Robinia pseudoacacia var. umbraculifera, commonly called umbrella black locust were regenerated after co-cultivation of internode segments with Agrobacterium tumefaciens which included yeast cadmium factor 1 (YCF 1) gene. The tolerance to cadmium and lead for plants can be increased by the YCF1 gene expression. Moreover, the recent studies have shown that YCF1 gene transgenic plants increase the accumulation of cadmium and lead into plant vacuoles. The effect of plant growth regulator such as 2,4-dichlorophenoxyacetic acid (2,4-D), ${\alpha}$-naphthaleneacetic acid (NAA), 6-benzyladenine (BA), and thidiazuron (TDZ) were studied to evaluate the propagation of plants through internode explants. The efficient induction of multiple adventitious shoots and callus were observed on a medium supplemented with 0.1 mg/L TDZ + 0.2 mg/L BA. To induce shoot elongation and rooting, regenerated shoots were transferred into basal MS medium without any plant growth regulator. Successful Agrobacterium tumefaciens mediated transformation was obtained by 20 min vacuum-infiltration with $50{\mu}M$ acetosyringone on the optimal multiple shoot induction medium with 30 mg/L hygromycin and 300 mg/L cefotaxime. To confirm the integration and expression of transgene, Polymerase Chain Reaction (PCR) and Reverse Transcriptase PCR (RT-PCR) were performed with specific primers. The frequency of transformation was approximately 18.94%. This study can be used to genetic engineering of phytoremediator.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.30-36
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• 2011

Effect of daminozide concentration and application methods, in combination with different planting period, on the growth of chrysanthemum was investigated for small pot-plant production. Daminozide, a plant growth regulator widely used for plant height control, was applied by drench or sub-application. For pot chrysanthemums of first planting time, plant height was reduced over $4,000mg{\cdot}L^{-1}$, when daminozide was drenched directly into the pot medium. However, $5,000mg{\cdot}L^{-1}$ of daminozide drench affected plant height reduction for secondarily planted pot chrysanthemum. Analysis of variance revealed the plant height was affected by planting time. For sub-application experiment of daminozide, it showed that the daminozide affected the number of flower buds formation and fresh and dry weight. These results suggest that planting period affected growth retardation of chrysanthemum. Therefore, application of growth retardant in combination with planting time and application methods may provide more efficient growth control for pot-chrysanthemum production.

• Journal of Plant Biotechnology
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• v.36 no.2
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• pp.174-178
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• 2009

Presently, we report a simple, reproducible and high frequency plant regeneration in Hibiscus syriacus L. using axillary buds. H. syriacus was regenerated from axillary buds directly or through a callus phase. Regenerated shoots were directly induced from young and fresh axillary buds cultured on Murashige and Skoog medium (MS) supplemented with 0.01 mg/L of the growth regulator thidiazuron (TDZ) after 2 weeks of culture. Directly induced shoots were transferred to hormone-free MS medium and root development was observed after 6 weeks. On the other hand, old and stale axillary buds were regenerated to shoots via callus induction on MS medium containing 0.01–2 mg/L TDZ after 4 weeks. A TDZ concentration of 0.01 mg/L was most effective in callus formation. Green callus was transferred to MS medium containing 0.01 mg/L α-naphthalene acetic acid (NAA) and 0.5 mg/L benzylaminopurine (BA). After 4 weeks, callus had developed into multiple shoots. Plantlets were formed from 10 week cultures of single shoots on hormone-free MS medium. Regenerated plantlets were cultured on MS medium for one month and then transferred to pots containing garden soil. Potted plants were acclimatized for one month and grown to maturity under greenhouse conditions. The present study has shown that various concentrations of plant growth regulator can be effective for in vitro plant regeneration of H. syriacus. The direct and indirect regeneration protocol presented here will be useful for understanding the manipulation and propagation of H. syriacus.

• Journal of Life Science
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• v.9 no.5
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• pp.564-569
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• 1999

This study was conducted to determine the concentrations of plant growth regulators required for regeneration and the concentrations of antibiotics for the selection of transformed regenerants from lettuce, musk melon and tomato. The optimal concentrations of plant growth regulators for shoot formation were NAA 0.1 mg/$\ell$ +BA 0.1 mg/$\ell$ for lettuce, NAA 0.01 mg/$\ell$ +BA 2.0 mg/$\ell$ for melon and NAA 0.1 mg/$\ell$ +BA 0.5 mg/$\ell$for musk melon. Shoot induction from tomato, lettuce and melon was completely inhibited by 30 mg/$\ell$ or higher concentrations of kanamycin. Shoot formation from mu나 melon was not affected by kanamycin up to 40 mg/$\ell$, but was reduced in the presence of 50 mg/$\ell$ and completely inhibited by 100 mg/$\ell$. Shoot formation of all four crops was completely inhibited by higromycin at 10 mg/$\ell$. Both carbenicillin and cefatoxinme did not show any negative effects on shoot formation.