Abstract
Cell suspension cultures of potato ( Solanum tuberosum , cv. Tamasha) were treated with fusaric acid (FA), a nonspecific fungal toxin produced by Fusarium species to study the effects of FA on H 2 O 2 generation, lipid peroxidation, and activities of antioxidant enzymes, i.e., superoxide dismutase (SOD), catalase, and ascorbate peroxidase (APX). The toxicity of various FA doses was evaluated from viability of cultured cells of S. tuberosum . The toxic concentration of FA (10 −3 M) reduced cell viability by 32% after 48-h incubation and induced alkalinization of the medium; the nontoxic concentration of FA (10 −6 M) had no effect on cell viability and pH of the culturing medium. The treatment of cells with FA caused rapid reversible accumulation of H 2 O 2 in cells, promoted lipid peroxidation, and elevated the activity of antioxidant enzymes. The toxic FA concentration elevated the intracellular H 2 O 2 content by 51–59% and stimulated lipid peroxidation rate by 35–40%. The nontoxic FA concentration raised the H 2 O 2 content by 84–91% and enhanced lipid peroxidation rate by 18–24%. The addition of FA induced transient biphasic induction of the antioxidant enzymes; the action of toxic and nontoxic concentrations differed in terms of the response amplitudes and dynamics. The results confirm the well-known toxic impact of high doses of FA on the cultured cells, which is determined by membrane transport disorders. In addition, the results reveal that toxic and nontoxic concentrations of FA are able to induce pro- and antioxidant systems in the cultured cells of S. tuberosum .