• Journal of Plant Biology
• /
• v.36 no.1
• /
• pp.19-27
• /
• 1993

Effects of polyamines on DNA synthesis were studied in synchronized culture of Nicotiana tabacum L. When DFMO and DFMA, inhibitors of ornithine decarboxylase and arginine decarboxylase, respectively were initially applied to the cells, the polyamine contents were rapidly dropped and [methyl-3H] thymidine incorporation into DNA was markedly reduced during the early stage of culture period. Inhibition of DNA synthesis, however, was partially reversed when these inhibitors were applied simultaneously with putrescine. In addition, exogenous administration of putrescine also increased the DNA synthesis during the all over the culture period. In vitro activity of DNA polymerase from Nicotiana tabacum L. was promoted by increasing concentrations of polyamines in the reaction mixture. Maximal activity was shown at 5 mM putrscine, 0.5 mM spermidine and spermine, respectively. Lack of Mg2+ ion in the reaction buffer resulted in an inhibition of the enzyme activity by about 30%. The inhibition could not be completely reversed by application of polyamines at optimal concentrations. These results suggest that polyamines promote the DNA synthesis in vivo and in vitro by stabilizing the DNA-helix upon binding to negatively charged groups on DNA or increasing the activity of DNA polymerase in Nicotiana tabacum L.

• Journal of Plant Biology
• /
• v.30 no.4
• /
• pp.287-298
• /
• 1987

The regenerative capacities of protoplasts isolated from potato (Solamum tuberosum L.) tubers and tobacco (Nicotiana tabacum L.) mesophyll tissues were examined, and then their intergeneric protoplast fusion was carried out. The potato tuber-derived protoplasts proliferated into the calli some of which showed rudimentary shoot-like structures, which had not been attempted before from tubers, while the tobacco protoplasts were regenerated into the whole plants. Intergeneric protoplast fusion between potato and tobacco was carried out and the heteroplasmic fusion products were formed. The first cell division of some of them was observed after 5 days of culture.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.11
• /
• pp.11-80
• /
• 1972

• Proceedings of the Korean Society of Crop Science Conference
• /
• 1990.10a
• /
• pp.42-43
• /
• 1990

• Natural Product Sciences
• /
• v.7 no.1
• /
• pp.17-20
• /
• 2001

The activity of the lipase and phospholipase extracted from the seed meal of Nicotiana tabacum L. was studied with the help of Spectrophotometer at different pH, Temperatures and Solvents. Both lipase and phospholipase shown optimum activity at pH 6 and $45^{\circ}C$. Their activities also maximize when n-heptane was used as solvent media.

• Natural Product Sciences
• /
• v.7 no.4
• /
• pp.110-113
• /
• 2001

The lipid classes constituents; hydrocarbons, wax esters, sterol esters, triacylglycerols, free fatty acids, 1,3-diacylglycerols, 1,2-diacylglycerols, free sterols, 2-monoacylglycerols, 1-monoacylglycerols, phosphatidylethanolamines, phosphatidylcholines, lysophosphatidylethanolamines and phosphatidylinositols of Nicotiana tabacum L. seeds oil were investigated by thin layer and gas chromatography. Palmitic, oleic and linoleic acids were the major components in all lipid classes studied.

• Journal of the Korean Society of Tobacco Science
• /
• v.1 no.1
• /
• pp.9-13
• /
• 1979

Dihaploid lines of tobacco (Nicotiana Tabacum L.) were developed from vitro anther culture of single cross F 1, "SC 72"X "Hicks". All genetic materials were evaluated for agronomic performance and chemical composition. Compared with midparent value, pollen derived dihaploid progenies showed reduced vigor in all measured features of plant growth, and increased total alkaloids as well as decreased reducing sugar content.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 1988.02a
• /
• pp.94-95
• /
• 1988

• Korean Journal of Plant Tissue Culture
• /
• v.27 no.6
• /
• pp.469-474
• /
• 2000

Effect of the antibiotic carbenicillin on callus and shoot formation from the leaf disc culture of tobacco (Nicotiana tabacum L. cv. BY-4) was examined. The number of shoot induced from the leaf explants was decreased as the amount of carbenicillin increased from 250 mg/L to 2,000 mg/L on MS medium containing 0.5 mg/L of BAP or kinetin. In addition, calli formation from the leaf explants was increased by the treatment of 250 mg/L ∼ 500 mg/L carbenicillin with or without 0.5 mg/L of 2,4-D or NAA. However, the fresh weight of 4-week-cultured explants was decreased with increasing carbenicillin from 250 mg/L to 2,000 mg/L on MS medium containing 0.5 mg/L of 2,4-D or NAA. These results indicate that carbenicillin has an auxin-like effect, such as promoting callus formation and inhibiting shoot induction. It leads to the conclusion that the auxin-like property should be taken into account for the production of transgenic plants via Agrobacterium-mediated transformation.

• Journal of the Korean Society of Tobacco Science
• /
• v.1 no.1
• /
• pp.46-50
• /
• 1979

Four cytoplasmic male-sterile lines of burley tobacco (Nicotiana tabacum L. ) and their male- fertile counterparts were evaluated for their characteristics in replicated field trials. Cytoplasmic male -sterile lines were comparable to the male- fertile varieties for agronomic and chemical traits and these suggest that the cytoplasmic male - sterility can be used in the production of hybrid seed without loss of vigour or undesirable changes On other characteristics.