Trehalose-induced modulation of antioxidative defence system in radish (Raphanus sativus L.) plants subjected to water-deficit conditions

Fifteen-day-old radish seedlings were subjected to water-deficit conditions as well as well-watered conditions. After one month of water-deficit treatments, two (25 and 50 mM) trehalose concentrations together with control (water spray only) were applied as a foliar spray. Both concentrations of trehalose improved plant fresh and dry biomass, ascorbic acid (AsA), total phenolics and activity of catalase (CAT) under both water regimes. A not significant influence of exogenously-applied trehalose was found on the accumulation of hydrogen peroxide, glycinebetaine, malondialdehyde, proline and activities of peroxidase, CAT, and superoxide dismutase enzymes. Overall, water stress altered the growth and oxidative defence system of radish plants. Foliar-applied trehalose improved growth of radish plants, and this improvement is associated with trehalose-induced increase in total phenolics, AsA content and activity of CAT, particularly under stress conditions.