<p>Pregermination seed treatment has become an interesting technique for agricultural improvement. One of these pretreatment techniques involves soaking seeds in solutions containing chemical substances known as biostimulants. Silicon is an inorganic biostimulant with many advantages, conferring tolerance to abiotic and biotic stresses on plants. However, while many studies have investigated the impact of silicon on whole plants, very few studies have focused on seed pretreatment with silicon, particularly under favorable conditions. In this study, we focused on investigating the effects of silicon pretreatment at different concentrations on the germination, development, nitrogen metabolism, and redox status of <i>Vigna unguiculata</i> seeds. Moreover, we focused on the colorimetric determination of silicon at the embryonic level to test its penetration into seed embryos during treatment. Our results indicated that pregermination treatment with Si at moderate concentrations significantly improved germination performance and radicle development. However, at high doses, silicon becomes toxic, completely inhibiting germination, following the induction of oxidative damage and the progressive inhibition of some hydrolytic and antioxidant enzymes. Our study also revealed that silicon penetrated the tissues of seed embryos in a gradual and steady manner but in small quantities. However, silicon transporters in this organ are currently poorly understood, hence the importance of a molecular study in this regard.</p>