Enhanced drought tolerance in transgenic potato expressing the Arabidopsis thaliana Cu/Zn superoxide dismutase gene

All aerobic organisms must possess the means to protect themselves from the toxic effects of reduced oxygen species generated during the normal metabolic activity of cells or as a result of environmental stresses such as drought. Cells are protected from the deleterious effects of free oxygen radicals by Cu/Zn superoxide dismutase (SOD), which catalyses the initial step in neutralizing activated oxygen species. In the study reported here, the potato cultivar Aviva was transformed with a cytosolic Cu/Zn superoxide dismutase gene from Arabidopsis thaliana using Agrobacterium-mediated gene transformation. Four transgenic potato lines were identified and evaluated for drought tolerance in the greenhouse. Two transformed lines could withstand drought in the greenhouse for two weeks longer than the untransformed plants and one week longer than two other transformed lines. These findings were confirmed by data from enzyme activity as well as by 2,3,5-triphenyltetrazolium chloride reduction.