Influence of Green Synthesized Silver and Zinc Nanoparticle on Seed Quality Attributes in Red Sander (Pterocarpus santalinus Linn.)

Red Sanders (Pterocarpus santalinus), or Rakta chandana, is an endangered tree native to the Southern Indian Peninsula, valued for its medicinal and dye properties. However, its germination is hindered by a hard seed coat, phenolic compounds and hormonal imbalances. Nanotechnology in forestry enhances product innovation, paper processes and sustainability through plant-based nanoparticle biosynthesis. The experiment used a completely randomized design (CRD) with three replications and evaluated seven presowing treatments: T1 (AgNPs at 1000 ppm for 24 hours), T2 (ZnNPs at 2000 ppm for 24 hours), T3 (Conc. H2SO4 for 12 minutes), T4 (NaDC 500 ppm), T5 (Dewinging), T6 (soaking in hot water at 100°C for 5 minutes) and T7 (control). The results indicated that seeds treated with ZnNPs at 2000 ppm (T2) exhibited highest germination rate (56%), germination speed (1.04), root length (17.05 cm), shoot length (16.33cm) and highest dry weight (6.22 g) and highest seedling vigour Index-I (1869). In comparison H2SO4 treatment (T3) delivered 51.67 per cent germination and a speed of germination (0.95), with root length (15.28 cm), shoot length (16.22 cm), dry weight (5.24 g) and seedling vigour Index (1628) slightly lower but still significant. The control (T7) had the lowest performance with 31 per cent germination, a speed of 0.36, root length (15.28 cm), shoot length (16.22 cm), lower dry weight (1.63 g) and the lowest Seedling Vigour Index (649). Overall, ZnNPs at 2000 ppm (T2) were the most effective in enhancing germination, seedling growth and overall vigour in Red sanders.