Effects of seed priming on growth and antioxidant components of hairy vetch (Vicia villosa) seedlings under chilling stress

Abstract

Hairy vetch (Vicia villosa) is an important cover crop and green manure in dryland cropping system of Mediterranean regions. A delay in the onset of rainfall during autumn can inhibit hairy vetch seed germination, which exposes its early growth stages to low-temperature stress. The present study was carried out in a completely randomized design with four replications to evaluate the effects of seed priming on germination of hairy vetch under chilling stress. The treatments were seed-priming type (unprimed, hydro-priming, halo-priming, and osmopriming) and temperature (3, 6, 9, 12, and 15 °C). The results indicated that a decrease in temperature produced a linear decline in the germination rate of seeds treated with halo-priming and osmopriming (p < .01). The seedling length, seedling dry weight, and vigor index decreased in plants experiencing chilling stress (quadratic; p < .01) for hydro-priming, halo-priming, and osmopriming. The maximum germination rate was achieved using hydro-priming. Osmopriming prevented a decrease in the rate of germination at 3 °C. A decrease in temperature increased the proline and the soluble protein contents in all the seed priming treatments, but, decreased catalase and guaiacol peroxidase activity (p < .01). In brief, halo-priming, and hydro-priming enhanced establishment and growth of hairy vetch under chilling stress primarily through improvements in the physiological parameters and germination rate. This finding can increase the potential for cultivation of the hairy vetch in late planting date.