Superoxide Dismutase Transgenes in Sugarbeets Confer Resistance to Oxidative Agents and the Fungus C. beticola

Sugarbeets carrying superoxide dismutase transgenes were developed in order to investigate the possibility of enhancing their resistance to oxidative stress. Binary T-DNA vectors carrying the chloroplastic and cytosolic superoxide dismutase genes from tomato, were used for Agrobacterium-mediated transformation of sugarbeet petioles. The transgenic plants were subjected to treatments known to cause oxidative stress, such as the herbicide methyl viologen and a natural photosensitizer toxin produced by the fungus Cercospora beticola, namely cercosporin. The transgenic plants exhibited increased tolerance to methyl viologen, to pure cercosporin, as well as to leaf infection with the fungus C. beticola.