Antioxidant Responses of Transplastomic Tobacco Plants with Chloroplast omega-3 Desaturase Gene under Low Temperature Stress

We studied the reaction to the oxidative component of low temperature stress in tobacco lines, transformed with gene coding for chloroplast ω-3 desaturase with their wild type. The levels of oxidative stress markers malondialdehyde as well as the activity of antioxidative enzymes catalase and peroxidase have been followed at acclimation, 3 and 6 days at 5°C treatment. Low temperature stress resulted in damage for the wild type and transplastomic plants. A corresponding increase of malondialdehyde contents in wild type plants, but the increase in transplastomic lines was significantly lower than that in wild type plants. A rise of peroxidase activity and catalase activity occurred in the wild type and transplastomic plants, but significantly higher trend of the same parameters has been found for the transplastomic lines. It could be suggested that transfer of chloroplast ω-3 desaturase gene is related to reduced intensity of low temperature-induced oxidative processes.