• Korean Journal of Plant Tissue Culture
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• v.25 no.2
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• pp.135-139
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• 1998

Reciprocal interspecific hybrids between N. glauca(2n=24) and N. langsdorffii(2n=18) were obtained by intercrossing. One hundred percent of F$_1$ seeds was produced from intercrossing of N. glauca $\times$ N. langsdorffii, whereas the frequency of F$_1$ hybrid seed formation from N. langsdorffii $\times$ N. glauca was very low. However, all the hybrid seeds were germinated well and then grown to normal plantlets. All the plants of F$_1$ hybrids have chromosome number of interspecific hybrids (2n=21). From observation of morphological characteristic, the structure of petrol, leaf, flower, and the morphology of pollen have characteristics of F1 hybrid. Spontaneous tumors (genetic tumor) were formed from each F$_1$ hybrid; the genetic tumor arose at the reproductive phase when the maternal type of F$_1$ hybrid came from N. glauca, while the genetic tumor arose only after reproductive phase when the maternal type of F$_1$ hybrid came from N. langsdorffii. The genetic tumor actively proliferated on hormone-free medium and produced numerous teratoma shoots. In addition, normal leaf or stem explants of F$_1$ hybrid produced calli on hormone-free medium after 15 days of culture, the calli produced new numerous teratoma shoots after 30 days. The frequency of teratoma shoot formation from rnterspecific hybrid was higher in the N. glauca $\times$ N. langsdorffii than in the N. langsdorffii $\times$ N. glauca. Root development from the teratoma shoots was hardly obtained. Teratoma shoots without roots in vitro can form genetic tumor at the vegetative growth phase after tissue culture.

• Korean Journal of Plant Tissue Culture
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• v.26 no.1
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• pp.31-35
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• 1999

Morphological characteristic during formation of tobacco crown gall tumor and genetic tumor, and their differential response to growth regulator were investigated in in vitro culture. Crown gall tumor was induced from tumor tissue transformed by infecting Agrobacterium tumefaciens C58. Genetic tumor was induced from tumor tissue which was induced spontaneously from reciprocal interspecific hybrids between Nicotiana glauca (2n=24) and Nicotiana langsdorffii (2n=18). Morphological characteristic of crown gall tumor, genetic tumor, and teratoma shoot was very similar, and they were actively proliferated on hormone-free medium. Typical tumor callus and teratoma shoot formed from crown gall tumor on the hormone-free medium. On the contrary, tumor callus derived from genetic tumor formed as a crown gall tumor callus on the medium supplemented with 0.5 mg/L of 2,4-D, and lots of teratoma shoots without any root formed on the hormone-free medium. Root development from the teratoma shoots was hardly obtained on the medium with IAA, GA and active carbon. However, teratoma shoots with roots, as normal shoots, were initiated occasionally on the hormone-free medium. These shoots also formed new genetic tumor on the stem, which leaves formed lots of teratoma shoot on the hormone-free medium in in vitro culture.

• Journal of Wetlands Research
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• v.2 no.2
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• pp.117-131
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• 2000

The flora and vegetaion of the high moor in Mt. Daeam($128^{\circ}07^{\prime}E$, $38^{\circ}13^{\prime}N$) was investigated by the phytosociological method of Braun-Blanquet's from 13 - 14th June to 7 - 8th August, 1998. The flora of plants recorded in high moor was 191 taxa belonging to 53 families, 131 genera, 160 species, 30 varieties, 1 formas. The high moor vegetation of Sanguisorba tenuifolia var. alba community group in this survey trip was classified into 11 communities as follows : Carex dispalata community and Sphagnum palustre community at the interior of moor, Carex biwensis community and Juncus papillosus community at the regenerated area and Malinia japonica community, Spiraea salicifolia community, Geranium eriosteman var. megalanthum - Calamagrostis langsdorffii community, Juncus effusus var. decipiens community, Salix koreensis community, Caltha palustris var. membranacea community and Sparganium stoloniferum community at the margin of moor. As a result of this study, the change of plant communities on high moor was closely influenced by landization in relation to the disturbance of human since 1969.