• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.1
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• pp.71-76
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• 1992

Starch gel electrophoresis was used to examine the banding pattern of Esterase isozyme in the leaf, root-nodule and seedling of four wild legume species, Trifolim repense, Glycine soja, Phaseolus nipponensis and Vigna uexillata. The number of band, enzyme activity and migrating rate of esterase isozyme varies depending on the species and tissues of legume plants. The isozyme banding pattern in the cotyledon and radicle of T. repense showed same pattern, however, the number of band were varible among the cotyledon of G. soja, P. nipponensis and V. vexzllata, respectively. Est-1 in the leaf of G. soja, V, vexillata. root-nodule of G. soja and seedling of V. vexillata expreesed the highest enzyme activity. The Est-1 showed the rapidest migrating rate among the isozymes.

• Journal of Plant Biology
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• v.37 no.2
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• pp.159-166
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• 1994

Direct current (DC) applied to cotyledons during a 16 h inductive dark period inhibited the flowering in the short-day plant, Pharbitis nil Choisy cv. Violet. The inhibitory effect of DC was more profound when the current flowed from roots to cotyledons, showing its polarity-dependent action. The second half on the inductive dark period was more sensitive to DC stimulus. The flowering was significantly depressed only when DC stimuli were applied to the translocation path of the floral stimulus from the induced cotyledon to the apex, suggesting that the transport of floral stimulus was damaged by the DC treatment. The vegetative apex culture bioassay system showed that a significant level of the floral stimulus activity existed in the phloem exudate from the cotyledons which would fail to form their own floral buds. These results strongly support the hypothesis that DC partially impede, at least temporarily, the transmission path of the floral stimulus from florally-induced cotyledon to the apex, rather than depressing in situ synthesis of the floral stimulus.

• Preventive Nutrition and Food Science
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• v.6 no.1
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• pp.29-37
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• 2001

The mobilization of food reserves and ultrastructural changes in th cotyledons of germinating soybean seeds (Glycine max L. Mer. Cultivar Amsoy) and seedlings were studied by using light and transmission electron microscopy. When germinating began, the cotyledon tissues were packed with protein an lipid bodies. Mobilization of the reserves started in epidermis and vascular bundles. After three days of seedling growth, significant reductions of protein and lipid bodies were observed; concurrently, the numbers of starch grains, glyoxysoms, and mitochondria were increased. These ultrastructural changes are discussed with reference to the metabolism of the germinating soybean seeds and seedlings.

• Journal of Plant Biotechnology
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• v.6 no.4
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• pp.253-258
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• 2004

Plant regeneration depending on explant type was inves-tigated with cotyledon, hypocotyl, and leaf explants of garland chrysanthemum (Chrysanthemum coronarium L.) cultured on MS basal medium supplemented with various concentrations of SAP and NAA combination. Among the three different types of explants, hypocotyl explants grown on MS medium containing $1.0{\mu}M\;NAA,\;1.0{\mu}M\;BA\;and\;6{\mu}M\;AgNO_3$ produced the highest adventitious shoots (4.67 per explant). Hypocotyl explants not only produced more vigorous shoots, which regenerated aster than the cotyledon and leaf explants. An efficient root formation was observed in MS medium containing $3\%$sucrose. The concentration of NAA did not show significant effects on root formation. Results from this experiment suggested that hypocotyl explants were efficient for the regeneration of garland chrysanthemum.

• Journal of Life Science
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• v.11 no.3
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• pp.254-258
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• 2001

The biochemical change during regeneration of perilla callus were investigated by comparing total protein and lipid contents, protein band pattern in SDS-PAGE, and fatty acid composition in the calli cultured for various period(0, 1, 3, 5 and 6 weeks) Calli were induced from cotyledon and hypocotyl explants of peplants of perilla on perilla on MS medium containing BA(0.5 mg/L) and NAA(0.5mg/L). The protein contents reached the peak at 3 weeks after induction of calli, and then was decreased. Total lipid contents was decreased as the culture period increased. The band pattern of polypeptides showed that 30KD and 45KD polypeptides and 22KD and 45KD polypetides were major proteins in the cotyledon and hypocotyl explants, respectively. However increase of culture period only 30KD protein was highly accumulated.

• Journal of Plant Biology
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• v.37 no.3
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• pp.365-370
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• 1994

Excised cotyledon segments of ginseng zygotic embryos at various developmental stages were cultured on MS basal medium from which somatic embryos were directly induced. The frequency of somatic embryo formation on the segments declined with the advancing zygotic embryo maturity. All of the cells in the cotyledons of immature zygotic embryos were smaller and more densely cytoplasmic than those in mature embryos. Histological examinations revealed that the poly-somatic embryos formed on immature embryos were of multi-cell originand derived from the epidermal and subepidermal cell layers. However, in the cotyledon of germinating zygotic embryos, only theepidermal cells were densely cytoplasmic and singularly competent to develop into somatic embryos resulting into single embryos at a frequency of 100%.

• Journal of Plant Biology
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• v.26 no.4
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• pp.207-216
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• 1983

Mature embryo and developing seedlings of Ginkgo biloba L. were embedded in a paraplast and serially sectioned at 10${\mu}{\textrm}{m}$ to examine vascular differentiation and vascular transition. Procambium and protophloem formed a continuous system along the epicotylhypocotyl root axis and cotyledons in mature embryo, whereas protoxylem was differentiated discontinuously in the cotyledons and rarely in the upper hypocotyl. The traces of the first and second leaf primordia apeared almost at the same time oppositely to each otehr at the epicotyl and alternately with the cotyledon traces in the upper hypocotyl. The trace differentiated bidirectionally toward the epicotyl and root tips. the young root initially formed a diarch xylem. Then, as the traces of the first and second leaves were superimposed, the diarch xylem. Then, as the traces of the first and second leaves were superimposed, the diarch xylem of the root was changed totriarch and tetrarch xylem, respectively. On the formation of primary vascular system of Ginkgo biloba, it is suggested that the primary phloem forms a continuous system throughout the seedling, whereas the primary xylem of the epicotyl is formed independently from that of the root-hypocotyl cotyledon system.

• Animal cells and systems
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• v.9 no.3
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• pp.127-133
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• 2005

We investigated expression of cucumber senescence-associated genes (SAGs) from developing cotyledons and flower petals. Several cucumber SAGs have been reported in earlier reports. This is an extension of the previous findings. Semi-quantitative RT-PCR revealed that most of the cucumber SAG transcripts were consistently produced until the organ senescence. These results imply that many cucumber senescence-related genes are still active during the final development stage, playing some executive biological roles, possibly in remobilization of nutrients to the other parts of tissues or organs. These results were used to search for possible functions of senescence-related genes during organ development.

• Plant Resources
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• v.2 no.1
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• pp.16-21
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• 1999

An efficient regeneration system was established by using in vitro plantlets of germinated seedlings from different cultivars of lettuce (Lactuca sativa cv. Chongchima, Chongchuckmyun, Jeokchima, Jeokchuckmyun). Shoot formation were observed from all cultivars on MS medium supplemented with 0.1 mg/L NAA and 0.5 mg/L BA. In all cultivars, when cotyledon was cultured, the number of shoot per explant was more greater than that hypocotyl and leaf disc were cultured. Shoot formation rate (91.7%) was high in a cotyledon culture of cultivar, Chongchukmyun. The growth of multiple shoots derived from the cultivar, Chongchukmyun, was most effective on medium containing 0.5 mg/L BA and 1.0 mg/L GA$_3$. When shoots were transferred on MS medium without plant growth regulators, roots were effectively differentiated. Rooted plantlets were acclimated on pots for further propagation.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1998.06b
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• pp.309-314
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• 1998