• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.134-137
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• 1999

An experiment was carried out to determine the effects of priming and growth regulator treatment of seeds on the emergence and seedling growth of rice, Oryza sativa L. (cv. 'Ilpumbyeo'). Normal seeds were primed in a -0.6 MPa polyethylene glycol solution at 15$^{\circ}C$ for four days with air-bubbling. Then both primed and non-primed seeds were soaked in water, 100 ppm GA$_3$, 2 ppm ABA, and 10 ppm kinetin solutions for 24 hours. The seeds were planted in soil at 3 and 5 cm depths and allowed to germinate in a growth cabinet at 2$0^{\circ}C$. Generally, the emergence rate at the 3 cm seeding depth was higher and emerged faster compared with the 5 cm seeding depth. The emergence rate of primed seeds was higher and emerged faster compared to non-primed seeds. GA$_3$ and kinetin treatments were the most effective to improve the emergence rate of non-primed seeds. Coleoptile length at the 5 cm seeding depth was longer than that at the 3 cm seeding depth. Leaf number, plant height, and root length of primed seedlings were higher compared with non-primed seeds. GA$_3$ promoted the elongation of plant height and mesocotyle length.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.138-142
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• 1999

An experiment was carried out to find out the changes in morphology, sugars, and $\alpha$-amylase activity during the priming of rice seeds (Oryza sativa L. cv. ＇Ilpumbyeo＇). For priming, seeds were soaked in -0.6 MPa PEG solution at 15$^{\circ}C$ for 4 days (properly primed) and at $25^{\circ}C$ for 4 and 10 days (over-primed) and dried at room temperature. The size of coleoptile and differentiated leaves of properly primed seeds were bigger and coleoptile was separated from the other part of embryo compared with non-primed and over-primed seeds. As priming of seeds advanced, compound starch grains in the endosperm disintegrated into tiny starch granules, and small holes were found in the tiny starch granules and a cavities developed between embryo and endosperm. The radicle and plumule of properly primed germinating seeds developed faster than non-primed and overprimed germinating seeds. Sucrose, maltose, and raffinose contents of properly primed seeds decreased, while content of glucose and fructose and $\alpha$-amylase activity increased. However, sugar content and $\alpha$-amylase activity of over-primed seeds were lower compared with non-primed seeds or properly primed seeds.

• Journal of Plant Biology
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• v.39 no.4
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• pp.287-293
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• 1996

The effect of taxol and ethyl-N-phenylcarbamate (EPC) on the growth and gravitropism of maize roots and coleoptiles was studied. Taxol is known to promote the assembly of microtubules (MTs) and stabilizes MTs by preventing depolymerization. EPC, on the contrary, is an anti-microtubule drug that promotes disassembly of MTs. Taxol, at 1 $\mu$M, inhibited gravitropic response of maize roots to about 40%, but did not inhibit growth; at 10 $\mu$M, it inhibited the gravitropic response of coleoptile segments of maize by approximately 50%, but did not inhibit growth, while 0.5 mM EPC inhibited both the gravitropic response and growth of maize roots by approximately 50%. Taxol, which inhibited the gravitropic response of maize roots and coleoptile segments, had no effect on either the polar or the bilateral transport of auxin. These results indicated that MT polymerization could not occur normally with taxol or EPC, so that if there was any abnormal rearrangement of MT, the gravitropic response was inhibited, which resulted from the inhibition of neither growth nor auxin transport. This results suggested that gravitropic response was related to the MT arrangement, and that both straight growth and the differential growth in gravitropic response could be regulated by different mechanisms.

• Korean Journal of Environmental Agriculture
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• v.14 no.1
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• pp.55-71
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• 1995

Wheat (Triticum aestivum L.) seeds were used to study a possible relationship between strontium and polyamines (PAs) in the coleoptile, root, and endosperm during germination. When $Sr^{2+}$ (0.001 mM + 10 mM) was applied to the incubation medium with $10\;{\mu}M$ $GA_3$, great increases in putrescine (Put) were observed in root and spermidine (Spd) in the coleoptile, depending on the concentration. In germinating seeds, putrescine accumulation was induced even at a low concentration (0.01 mM Sr), whereas spermidine accumulation was stimulated considerably at a high concentration (10 mM Sr). The putrescine levels, on a gram fresh weight (g-fr-wt) basis, in the roots which were growth-inhibited by 1 and 10 mM $Sr^{2+}$ were 22.4 and 15.3 fold higher respectively than at the same concentrations of $Ca^{2+}$. The accumulation of total polyamine (TA), in particular Put and Spd, induced by Sr seemed to be an important physiological response not only on a g fr wt basis but also on an RNA basis. In contrast, the levels of agmatine (Agm) and cadaverine (Cad) were notably enhanced by 10 mM $Ca^{2+}$ in the coleoptile and root. Cadaverine was detected only in $Ca^{2+}-treated$ seedlings. However, $Ca^{2+}-treatment$ in the range of 0.001 mM to 1.0 mM resulted in reduction of TA content. The distinction of accumulated polyamines and the change in diamine (DA) / TA and tri- and tertiary (tPA) / TA ratios were likely to be a physiological difference between $Sr^{2+}$ and $Ca^{2+}$ during germination in wheat.

• Journal of Plant Biology
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• v.19 no.1
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• pp.7-13
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• 1976

Biological activities of decursin and decursinol, natural coumarin derivatives, on the germination, growth and adventitious root formation of several plants were observed. In 10 ppm of decursin or decursinol, the growth of Avena coleoptile sections was inhibited, and the activity of IAA-oxidase was gradually enhanced by the increase of its concentrations. Inhibition effect on seed germination was observed from 100 ppm of each chemcials, and the activity of amylase in the germinating seeds was also gradually decreased. However, in the higher concentrations of decursin, the inhibited germination rate of wheat was slightly reduced. Decursin and decursinol also promoted the adventitious root formation in seeds of Phaseolus vulgaris.

• Proceedings of the Korean Society of Crop Science Conference
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• 2001.09a
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• pp.132-133
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• 2001

• Journal of Plant Biology
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• v.33 no.4
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• pp.321-323
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• 1990

Membrane proteins isolated from the coleoptile and mesocotyl tissues of corn seedlings were solubilized with Triton X100 and reconstituted with phosphatidylcholine at 2$0^{\circ}C$. The proteoliposomes were incubated and proton uptake into the vesicles was measured with a spectrophotometer. Addition of ATP to the reaction mixture was found to result in an active accumulation of proton into the vesicles. These results indicate that the preparation contains tightly bound phosphatidylcholine vesicles with reconstituted H+ -ATPase from the plant cell membranes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.16-23
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• 1987

This experiment was conducted to determine the isozymic differences between normal maize and maize inbreds of multiple ears and tillers (MET). Two maize inbreds Euisung, Iri and their hybrid having tillers and multiple ears were compared with normal maize. With usual electrophoresis using 6% polyacrylamide gel, peroxidase and esterase enzymes were studied. Matured leaf, culm, leaf sheath, root and young ear tissues showed different isozymic patterns between METs and normal maize in peroxidase. The Euisung inbred grown for 7 days under dark condition showed typical peroxidase. bands compared with checks in the tissues of coleoptile and stele. Better observation of isozymic bands was made during early part of maize growth. Parental inbreds showed more active and apparent band differences than their hybrids in esterase. Bands for esterase were also apparently different in the stele, coleoptile and young ear tissues of the METs and the checks. The maize lines infected with black streaked dwarf virus showed obvious differences in peroxidase and esterase isozymes.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.192-192
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• 2017

Direct-seeding cultivation of rice is increasing in Asia instead of transplanting system, because of its lower cost and operational simplicity. Low-temperature germinability (LTG) and anaerobic germinability (AG) are important characters for breeding of varieties for wide-spread adoption of direct-seeding cultivation in rice. This study was performed to characterize LTG and AG of seven rice varieties and identify varieties with strong germinability on both low-temperature and anaerobic conditions. The mean germination rate and germination vigor of seven varieties were 51.7% and 6.0 under low-temperature condition, respectively. Among these varieties, Cheongcheongjinmi and Hwanggeumnodeul had the highest germination rate of 80%, indicating that Cheongcheongjinmi and Hwanggeumnodeul have a good LTG. In anaerobic conditions, the germination rate and coleoptile length for all varieties were 47.6% and 3.2 cm, respectively. Of them, the highest germination rate and coleoptile length were observed in Subo and Hopum, respectively, suggesting that these two varieties are tolerant to anaerobic during germination stage. Molecular characterization by SDS-PAGE revealed that the protein patterns differed at 50 kDa, 40 kDa, and 22 kDa between low-temperature and anaerobic conditions. Varieties identified as good LTG or AG in this study may be used for developing new direct-seeding rice cultivars through pyramiding these traits in the breeding program.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.58-64
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• 1990

This study was conducted to investigate the interaction effect of a new plant growth regulator brassinolide and auxins using several bioassay methods such as rice lamina inclination test, oat coleoptile segment growth test and radish hypocotyl elongation test. For rice lamina inclination test, the antagonistic response showed at low concentration combinations of homobrassinolide and auxins (IAA and 2,4-D), while the combinations of high concentration responsed mostly synergistic or additive effects, IAA was generally higher than 2,4-D for combination effect with homobrassinolide. For oat coleoptile segment growth test, the synergistic effect showed at IAA concentrations less than 0.1ppm while additive response exhibited above 0.3ppm regardless of homobrassinolide concentrations. In radish hypocotyl elongation test, the interaction response varied with cotyledon. The sections removed cotyledon showed mostly antagonistic effects, except for combination of homobrassinolide with IAA 3ppm. Interaction responses were Quite different from bioassay methods, particularly using experimental materials: antagonistic responses were usually shown at the section that attached growing point while these for sections that removed growing point were responded synergistic or additive effect due to unstable endogenous hormones.