Seed Priming with Salicylic Acid Minimizes Oxidative Effects of Aluminum onTrifoliumSeedlings

Aluminum (Al) toxicity is one of the main aspects restricting the development of fabaceous plants grown in soils with spontaneous vegetation prevalence in temperate climate zones. Salicylic acid (SA) minimizes the effects of stress on plants. Therefore, the aim of the current study was to evaluate the ability of SA seed priming to mitigate the effects of Al on seed germination and seedling performance in twoTrifoliumspecies.Trifolium vesiculosum(annual) andTrifolium repens(perennial) seeds were primed in solution added, or not, with SA (25 mu M) and placed on germination paper moistened with aluminum sulfate (Al-2(SO4)(3)) solutions at three different doses: 0 mM (control), 0.25 mM (moderate dose), and 1.25 mM (high dose). Seed priming with SA has mitigated the global toxicity effects of Al onT. vesiculosumandT. repensseedlings. Inferior damages were observed inT. vesiculosumroot length and dry mass and inT. repensshoot dry mass, after SA pretreatment.T. vesiculosumseed priming with SA in the presence of Al has significantly reduced the osmotic potential of seedling sap. Salicylic acid (SA) has also enabled increased antioxidant activity of enzymes such as superoxide dismutase (SOD) in the two investigated plant species and ascorbate peroxidase (APX) inT. repens. In addition to the increased antioxidant activity, SA-primed seeds reduced the malondialdehyde content inT. vesiculosumseedlings exposed to Al. Overall, seed priming with SA mitigates oxidative effects of Al and improvesT. vesiculosumandT. repensseedling performance in the presence of this element.