• Journal of Life Science
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• v.14 no.4
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• pp.614-619
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• 2004

This study was undertaken to investigate the different responses of cultured plant cells to paraquat treatment and nucleus-DNA damage in relation to enzyme activity of superoxide dismutase (SOD). Furthermore, this study was also carried out to understand the antioxidative mechanism of plant cells to environmental stress. We selected two different species of plant cultured cells, Ipomoea batatas as high-SOD species and Lonicera japonica as low-SOD species. The total activity and specific activity of SOD in a chlorophyllous cell of I. batatas were 3,736 unit/gㆍfresh weight and 547 unit/mgㆍprotein, respectively, and those in L. japonica were 23 unit/gㆍfresh weight and 13 unit/mgㆍprotein, respectively SOD activity in chlorophyllous I. batatas cells reached its maximum level at 10 to 15 days after subculture, whereas that in L. japonica remained at a very low SOD level during the whole period of subculture. In comparison to L. japonica, I. batatas, a high-SOD species, showed high tolerance to paraquat 10 and 50 mg/l treatment in terms of cell viability and electrolyte leakage. Based on the result of comet assay, the nucleus-DNA damage of two species by paraquat 50 mg/l treatment was not significantly different. However, I. batatas cells repaired their damaged DNA more effectively than the cells of the low-SOD species, L. japonica.

• Korean Journal of Weed Science
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• v.11 no.2
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• pp.137-141
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• 1991

This study was conducted to determine the response of newly developed chlorophyllous cells against photosynthesis inhibitory herbicides in LS medium. Inhibition of the growth of the selected chlorophyllous cells in the LS medium containing sucrose 1%, NAA $10^{-5}$ M and BA $10^{-6}$ M under light condition increased as the concentrations of paraquat increased from $10^{-6}$ M to $10^{-4}$ M. The calli died in $10^{-4}$ M paraquat treatment and the inhibition of calli growth was greater when $CO_2$ was supplied. In the treatment of herbicide diuron, the inhibition of calli growth also increased as the concentrations of diuron increased from $10^{-6}$ M to $10^{-3}$ M and more inhibition was observed at 1% sucrose than 2% sucrose.