Improving vegetative growth and loral performance of tuberose (Agave amica medik. L. cv. ‘Single’) through combined soil and foliar applications of silica oxide (SiO2)

Silicon (Si) plays a crucial role in enhancing plant growth, structural integrity, and stress tolerance; however, its role in tuberose (Agave amica Medik.) remains insufficiently explored. A major challenge in tuberose cultivation is the limited understanding of how different modes and concentrations of Si application influence vegetative growth and floral quality under field conditions. Additionally, evidence-based recommendations on the optimal concentration and method of SiO₂ application are still lacking. The present study aimed to evaluate the effects of soil and foliar applications of silica oxide (SiO₂) on the growth, flowering, and postharvest attributes of tuberose. A factorial randomized block design (FRBD) comprising different combinations of soil and foliar SiO₂ treatments was employed, and vegetative as well as floral parameters were recorded at successive growth stages. Statistical analysis revealed significant (p < 0.05) main and interaction effects of SiO₂ treatments on all measured parameters. Among the treatments, T₁₅ (S₃F₃: 8.8 g/m² soil + 3% foliar) exhibited superior performance, achieving the maximum plant height (46.43 cm), leaf count (20.78 at 60 DAP), spike length (46.43 cm), and the earliest spike emergence (73.00 days). Postharvest evaluation showed that T₁₉ (S₄F₃) recorded the longest vase life (12.89 days), followed by T₁₅ (12.67 days), indicating a notable enhancement in floral longevity. These improvements may be attributed to silicon-mediated strengthening of cell walls, better water retention, and delayed senescence. Overall, this study provides new evidence on the optimised application of SiO₂ in tuberose, demonstrating that integrated soil and foliar supplementation at higher concentrations significantly improves morpho-physiological traits, postharvest performance, and ornamental value. The findings highlight the potential of SiO₂ application as a sustainable strategy for commercial tuberose production.