• Applied Biological Chemistry
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• v.12
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• pp.107-114
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• 1969

In order to elucidate the effects displayed by the plant growth regulators on the senecence of tobacco leaves, the author applied gibberellic acid, Kinetin, Indole-acetic acid, uracil, and malefic hydrazide to the excised leaves in concentration of 25mg/l of each regulators. And author obtained the results as following, 1. Parallel to the decreases of chlorophyll, the amounts of protein and RNA were decreased. 2. The supression of decrease of the amounts of RNA and protein was displayed by the plant growth regulators, G.A., I.A.A.. The decrease of them in M.A. treatments was more than in non-treatments. 3. The ratio changes of chlorophyll a/b and the changes of protein and RNA content seemed to be no relations.

• Applied Biological Chemistry
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• v.38 no.2
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• pp.123-128
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• 1995

Several factors affecting on transformation efficiency were studied to establish a Agrobacterium rhizogenes mediated system for the transformation of Populus species, and We could obtaine tansgenic plantlets expressing the introduced gene. Leaf sections were more sensitive than stem sections to kanamycin and thought to be better material for transformant screening. The bacterial density did not affect on the efficiency of transformation over the range of $4{\times}10^5{\sim}7{\times}10^9\;cfu$. The optimum period for co-cultivation was one day or shorter. Both of the optimum concentrations of cefotaxime and ampicillin in the medium were $250\;{\mu}g/ml$ for elimination of bacteria from the inoculated leaf sections. The addition of acetosyringone in the bacterial culture medium increased transformation rate, and the highest rate was obtained at $50\;{\mu}M$ of acetosyringone. The transformed galls could be selectively induced and gown on the growth regulator-free medium or on the medium containing $100\;{\mu}g/ml$ or higher contrition of kanamycin. The roots were induced from the galls incited by A. rhizogenes within 3 weeks on the growth regulator-free medium as well as on the medium containing growth regulators. The plantlets were regenerated from the galls cultured for 6 weeks on the medium containing 0.05 mg/ml of NAA and 0.5 mg/ml of BA. The expressions of the introduced opine gene in the transformed galls and plantlets were confirmed by the analysis of agropine and mannopine.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.1
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• pp.31-37
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• 1993

It is important to improve the germination of grass seeds because they are poor germination under water stress. This experiment was conducted to investigate the response of seeds pre-treated individually with Polyethylene glycol 6000 (PEG) and growth regulators(GA$_3$, Kinetin, NAA) on the germination characteristics when two levels of osmotic potential (0, -5 bar) were put to seeds of Orchardgrass. In the untreated seeds, the total germination rate was decreased under water stress, and the mean germination time was delayed. Priming of Orchardgrass seeds using PEG or GA$_3$ resulted in improved germination under water stress(-5 bar), whereas the opposite was true of kinetin or NAA. The response of seeds primed in solutions of either -15 bar PEG or 100 ppm GA$_3$ was particulary marked compared with the untreated seeds. It is suggested that PEG and GA$_3$ may have positive regulatory effects in triggering the system for water stress alleviation. But the inhibitory effect of the water stress was not completely removed by allowing the seeds to pre-treat in solution of PEG or GA$_3$.

• Korean Journal of Environmental Agriculture
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• v.37 no.2
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• pp.87-96
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• 2018

BACKGROUND: The vigorous shoot growth in upper part of apple tree canopy leads to poor fruit quality and flower bud formation in lower part of canopy. So, this study was conducted to develop the proper control method about the shoot growth in upper part of apple tree canopy. METHODS AND RESULTS: Trunks of 'Fuji'/M9 apple trees were cut (back pruned) to 2.5 m in tree height on 11 February (dormant) or 12 April (full bloom). Naphthalene acetic acid (NAA) was applied at 2.0% to cut surface when trunk was pruned. Prohexadione-calcium (Pro-Ca) was sprayed at 250 mg/L above 2.0 m in tree height at 23 April (petal fall). The NAA or Pro-Ca application after trunk was pruned at dormant (TR-2 and TR-3) significantly reduced shoot growth in upper part of canopy compared with the control (tree was only pruned at dormant, TR-1), but the percent of shoots showing the secondary growth of TR-3 was higher over 2 times than that of TR-2. The reduction of shoot growth in upper part of canopy by TR-2 and TR-3 increased the fruit red color from the lower part in the treating year and blooming of the lower part in the following year. CONCLUSION: Applying 2.0% NAA to cut surface of pruned apple trunk at dormant was the most effective way for stabilization of the tree vigor in upper part of the canopy in a high density apple orchard.

• Korean Journal of Plant Tissue Culture
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• v.21 no.4
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• pp.247-252
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• 1994

The effects of explant sources, plant growth regulators on callus induction and plantlet differentiation from leaf blade, petiole, and meristem tissue of Pelalgonium citrosa were investigated under illumination or in dark condition Leaf blade explants cultured on Murashige and Skoog's medium containing 2,4-D and kinetin did not form callus or organ. But those cultured on medium with NAA and BA produced callcus and shoots. Dark condition was more effective than light condition to callus induction and showed that some of shoot were differentiated directly from leaf blade explane. Callus proliferated vigorously on meristem tissue after 7 days of culture, and multiple shoots were obtained Sum callus on medium with 0.5 mg/L NAA and BA. Roots formed readily from about 80% of the shoots cultured on medium with 1.0 mg/L NAA. Regenerated plantlets regenerated had phenotypically normal leaves and roots.

• Journal of Plant Biotechnology
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• v.35 no.1
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• pp.47-53
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• 2008

Effects of growth regulators and culture conditions on seed germination, haustorium development, and callus formation of Korean mistletoe (Viscum album var. coloratum (Kom.) Ohwi) were described. Histological examination showed that seed of V. album contained one or two zygotic embryos with rod shape, and actively dividing cells were mainly distributed in radicle region rather than cotyledon of zygotic embryo. The most significant factor for seed germination and haustorium development of V. album was the requirement of the light. Various growth regulators examined in this study failed to substitute the effect of the light on seed germination. The frequency of callus formation was highest at 27.3% when flower buds were cultured onto B5 medium containing $0.1\;mgl^{-1}$ IAA. Explants from other organs were recalcitrant in forming calluses. Culture conditions described in this study could be applied for production of useful metabolites and multiplication of V. album in future.

• Journal of Sericultural and Entomological Science
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• v.35 no.2
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• pp.79-85
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• 1993

Winter dormancy of the mulberry(Morus species) in Suwon was investigated with regards to mulberry varieties, such as Kaeryangppong, Daeryunppon, Yongchionppong and Hongolppong application of fertilizers and growth hormone. In general, It initiated at late September and it subsequently became deeper and reached the highest degree through late October to early November. After that early November it gradually turned into the breaking state and was terminated by late November. Intensity and duration of dormancy were lower and shorter in Kaeryangppon. The standard application of N. P. K(30-13-18kg/10a) affects it delayed, but terminated earlier. On the other hand, the double amount of nitrogen affects the dormancy fast, but terminated late. The treatments of GA3 at the early and termination stages increased the bad sprouting. The contents of RNA and protein in the bark gradually increased as the dormancy becomes deeper.

• Journal of Ginseng Research
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• v.13 no.1
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• pp.79-83
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• 1989

This study was conducted to determine the effect of growth regulators, IBA, GA, and BA, on the adventitious bud formation, shoot differentiation, and inflorescence development in embryo culture of Korean ginseng. The adventitious bud formation and shoot differentiation were significantly promoted by application of a combination of 1 ma/l IBA and 5 mg/l GA. The adventitious buds had the primordial shoots and were differentiated as to plantlets. About 5 to 10 adventitious buds developed around the basal axis of the epicotyle of the ginseng embryo, and development of inflorescence was possible only after shoot differentiation. The MS medium supplemented with a combination of 3 mal 1 each of IBA, GA, and BA was most effective for in vitro inflorescence development, and the ratio of inflorescence formation was 18.4%.

• Journal of Environmental Science International
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• v.3 no.2
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• pp.141-155
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• 1994

The effect of growth regulators (NAA, BA and $ extrm{GA}_3$) and light (blue, red and far-red) on the changes in total protein and thylakoid membrane protein pattern of callus from intergeneric protoplast fusion between Nicotiana tabacum and Solanum nigrw were investigated. When the callus were irradiated with different wavelengths of light, blue and red light accelerated the synthesis of total proteins and thylakoid membrane proteins. Particularly, red light led to an increase in the protein synthesis compared to blue light. When the callus were subjected to various combinations of growth regulators, NAA+$ extrm{GA}_3$ and NAA+BA treatments induced remarkable increase of total proteins and thylakoid membrane proteins accumulation, particularly in the combination of NAA+$ extrm{GA}_3$. NAA.$ extrm{GA}_3$ treatment with irradiation of red ligh showed highest value in the accumulation of total proteins and thylakoid membrane proteins. We conclude that simultaneous application of red light and NAA+$ extrm{GA}_3$ treatment may induce synergistic effect in the synthesis of total proteins and thylakoid membrane Proteins.

• KSBB Journal
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• v.10 no.2
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• pp.143-148
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• 1995

The effects of various elicitors, metabolic inhibitors and growth regulators on the production of diterpenoid anticancer agent taxol were investigated in cell suspension cultures of Taxus brevifolia. Cell cultures of T. brevifolia were treated by 5 kinds of biotic elicitors, 5 kinds of abiotic elicitors, 2 kinds of metabolic inhibitors and 8 kinds of growth regulators at the end of exponential growth phase. Among those treatments, chlorocholine chloride-an inhibitor of plant steroid metabolism-increased the taxol production most significantly. From a series of optimization studies, it was found that the addition of 1mM of chlorocholine chloride at the 9th day of culture was the best for taxol production. Taxol yield under this condition was 0.72mg/$\ell$.