Improving Potato Plants Oxidative Stress and Salt Tolerance by Gene Transfer Both of Cu/Zn Superoxide Dismutase and Ascorbate Peroxidase / 中国生物工程杂志

ABSTRACT

In plants, oxidative stress is one of the major causes of damage as a result of various environmental stresses and it is primarily due to the excessive accumulation of reactive oxygen species. To develop transgenic potato plants with enhanced tolerance to environmental stress, transgenic potato plants (Solanum tuberosum L. cv. Atlantic) expressing the Cu/ZnSOD and APX genes in chloroplasts were generated under the control of the oxidative stress-inducible promoter. To investigate oxidative stress tolerance, transgenic plants were evaluated at the level of leaf discs and plantlets after methyl viologen (MV) and salt treatment. Leaf discs from transgenic potato plants showed 13% less membrane damage compared to non-transgenic (NT) plants suffering 10 μmol/L MV treatment of 48 h, and showed 1.6-fold higher chlorophyll contents than those of NT plants at 1.0mol/L NaCl treatment (31% vs. 19%). In addition, transgenic potato plants maintained higher rooting rates (75%) during 100mmol/L NaCl treatment than those (12%) from NT plants. Moreover, the tolerance to salt stress in transgenic plants was consistent to increased transcript levels and higher activities of SOD and APX compared to NT plants. These results suggest that expression of Cu/ZnSOD and APX in chloroplasts could be used in plants to enhance the tolerance to environmental stresses.