Response of antioxidant compounds to selenium and salicylic acid in wheat cultivars under dry land conditions

In the present study, three dry land wheat cultivars, Azar 2, Sardary and Rasad, were tested for antioxidant enzyme activity, proline, malondialdehyde (MDA) and dityrosine (DT) content and grain yield after treatment with selenium and salicylic acid (SA). A factorial field experiment was carried out based on a completely randomized block design with three replicates. The experimental factors were three levels of salicylic acid (without SA; seed priming with 0.5 mM SA; seed priming + spraying with 1 mM SA) and two levels of selenium (0 and 20 g/ha). Significant increases in the activity of the superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) enzymes and in the proline level were observed after treatment in the leaves of the three genotypes investigated, but this was associated with reduced MDA and DT content. The application of SA as seed priming and the foliar application of Se also increased the grain yield. These results suggest that cultivars exhibiting high antioxidant enzyme activity and proline content under dry land conditions may provide better drought tolerance in wheat.