• Applied Biological Chemistry
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• v.28 no.2
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• pp.82-87
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• 1985

Aiming at the improvement of accuracy and sensitivity of gibberellin analysis by gas chromatography-selected ion monitoring (GC-SIM), the mass spectra of two types of 29 gibberellin derivatives, methyl ester-trimethylsilyl ethers and trimethylsilyl ester-trimethylsilyl ethers, were obtained and their advantages and disadvantages in GC-SIM analysis are discussed.

• Journal of Plant Biology
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• v.17 no.2
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• pp.95-98
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• 1974

This experiment was undertaken with the purpose of investigating effect of gibberellin on the growth and electron microscopic ultrastructure of hop(Humulus lupulus var. Hallertau) shoot apex. The results are as follows. 1) The growth of stem in the plots treated with GA(10, 25, and 50ppm) is more predominant than control. The leaves and cones of treated plots turn to pale green. 10ppm plot of GA treatment is the most effective in growth and yield than the others. 2) Under the GA-treated condition, it is believed that the nucleoplasmic index (NP) are higher than the control, and so nucleus, nucleolus, mitochondria, primary cell wall, middle lamella, and etc. tends to be larger than the control. 3) Mitochondria contained in the cell of shoot apex treated with concentration of 10ppm GA was seemed to increases in number and be larger in size than the control.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.213-218
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• 1993

An experiment was carried out to investigate the effects of plant growth regulators on the growth and fiber yield of ramie. Gibberellin (GA) and Atonic acid were applied at the various levels of application dates, application frequencies and concentration. Stem growth of ramie increased greatly by applying GA on the meristem of shoot apex. Among three treatments of application frequencies of GA, that is, one time application at the stage of stem length with 50cm, twice applications at the stem length of 50cm and 100cm, and three times applications at stem length of 50cm, 100cm and 150cm, stem growth increased more as application frequency increased. GA application is more effective on stem growth at the later stage of growth than the earlier growth stage. GA treatment of 100 to 300 ppm is more effective on stem elongation than 50 ppm, which was due on the elongation of internodes without increase in number of nodes. One time application of GA enhanced leaf growth more or less regardless of concentration, but GA was applied more frequently, leaf growth was inhibited more at higher concentration. Fiber yield was the highest at the treatment of three times application of GA with 100 ppm. This treatment also showed the highest percentage of fiber with 5.3%, which is much higher value compared with that of control treatment with 4.6%. Atonic acid was less effective on stem elongation than GA, but it also seemed to be effective on the enhancement of fiber development.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.3
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• pp.317-322
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• 1997

In order to investigate vigor of rice seed pregerminated, some organic and inorganic component content, response of ecotypes, and effect of gibberellin treatment, under different levels of hastening of germination, were examined. Protein content was high in dried seed, the larger size in length of pregerminated seed, the less protein content, but lipid content was a reverse tendency to protein one. Potassium content was low in dried seed, the larger size in length of pregerminated seed, the more potassium content, but increase dramatically at above 10 mm in length of sprout. Magnesium content showed a same tendency to potassium one. The ability of regermination was high in early maturing cultivar, but almost lost in the pregerminated seeds with above 5 mm in length of sprout. The regermination percentage of dried seed was lower than that of pregerminated seed with 0.1∼0.5 mm in length, but was similar to that of pregerminated one with 1∼3 mm in length of sprout. The effect of gibberellin on regermination percentage was highest at 10 ppm and showed high with small sized one of pregerminated seed. The effect of gibberellin on plant height, fresh weight, and dry weight showed a same tendency to regermination percentage.

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.99.1-99.1
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• 2008

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.99.2-99.2
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• 2008

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.100.2-100.2
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• 2008

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.360-365
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• 1993

The infant seedling of rice(8-to 10-day-old) has often suffered from submergence just after transplanting due to the too short seedling height, 5 to 8cm, This experiment was conducted to elucidate the effect of gibberellic acid($GA_3 : 25% soluble liquid) with the application methods of foliar spray and seed-soaking on the elongation of seedling height of infant rice seedling in machine transplanting, We used a japonica rice variety, Hwaseongbyeo, and the seeding rate was 200g per seed tray(30$\times60$\times3cm). Generally,$GA_3 and Metalaxyl increased the elongation of seedling height of infant seedling while Tetracycle decreased the seedling height, To increase the seedling height of infant seedling, the foliar spary application of $GA_3 was better than seed-soaking treatment. The optimum concentration of $GA_3 for the foliar spray was about l0ppm and the optimum application time of $GA_3 was 3 to 4 days after sowing.

• Korean Journal of Medicinal Crop Science
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• v.3 no.3
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• pp.240-245
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• 1995

This study was conducted to find out environment conditions in order to increase of growth and yield of tuberlets in pinellia ternata (Thunb.) Breit. The optimal temperature conditions for the growth of tuberlets were good rather temperature fluctuations than constant one and the optimal photoperiod was a 6hr-photoperiod. The growth of tuberlets to the kinds and concentration of growth regulators was good for 0. lppm 2.4- D, 10ppm kinetin and 50ppm gibberellin treatment. In colchicine soaking treatment, the growth of tuberlets was bad, but bulblets formation was good for 0. 05% colchicine treatment for 48hr. -soaking. In colchicine dropping treatment, dry tuber yield was good for 0. 1% colchicine treatment with once dropping for one day.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.5
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• pp.548-555
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• 1997

Sorghum seedlings lacking one of the phytochromes, phyB, have elongated internode, suggesting that they may have an alteration in gibberellin physiology. To test the possibility that phyB mutations affect seedling gibberellin perception and metabolism, the responsiveness of wild-type and phyB-1 seedlings to exogenous $GA_3$ was investigated. The phyB-1 showed higher internode elongation rate than the wild type in response to lower concentrations of exogenous $GA_3$ application, showing that the mutation causes an increase in responsiveness to GA. However, at the higher concentrations of $GA_3$ application, phyB-l and wild-type showed similar elongation rate, impling that responsiveness to higher concentrations of GA is not controlled by phytochrome. These results suggest that, although GAs are required for internode elongation, phyB does not act primarily by changing absolute levels of GAs but rather by decreasing seedling responsiveness to GAs at lower concentrations.