Seed laser priming enhances defensive responses in milk thistle under Pb toxicity.

Heavy metal stress negatively affects the growth of medicinal plants. While the effects of Helium-Neon (He-Ne) laser on seed germination and stress tolerance in plants has garnered significant attention, little is known concerning the impacts of He-Ne laser irradiation on heavy metal tolerance in plants. Therefore, the current study was conducted to appraise the effect of different durations (0, 20, and 40 min) of seed priming with He-Ne laser (10 mW mm) on the antioxidant system of Silybum marianum L.