Effects of silicon nano-chelate on Tetranychus urticae populations and plant structural and physiological traits in rose cultivars

Roses are among the most economically important cut flowers globally, yet their production is severely impacted by two-spotted spider mites (Tetranychus urticae), which cause extensive damage and reduce marketability. This study evaluated the efficacy of silicon nano-chelate (N-Si) in suppressing mite populations and enhancing plant defenses in two rose cultivars, 'Jumilia' and 'Samurai', under controlled greenhouse conditions. A factorial experiment with six replicates was conducted. N-Si was applied at 2 mL L⁻¹ as a foliar spray every 10 days, while untreated plants served as controls. Results showed that N-Si significantly reduced mite populations, with egg, nymph, and adult counts declining by up to 67.5%, 98.4%, and 73.5%, respectively, after eight applications. Principal component analysis (PCA) revealed clear separation between treated and control samples, highlighting N-Si's significant influence on both pest suppression and plant physiological traits. N-Si application increased cell wall thickness by 64.4%, contributing to mechanical resistance against mite feeding, with 'Jumilia' showing the highest structural reinforcement. Nutrient concentrations of silicon, calcium, and boron were significantly elevated in treated plants, particularly in 'Samurai'. Photosynthetic pigments, including chlorophyll a, b, total chlorophyll, and carotenoids, increased by up to 28.3%, indicating improved physiological performance. Leaf area also expanded by 13.4% with N-Si, with 'Jumilia' exhibiting greater growth than 'Samurai'. These findings demonstrate that N-Si enhances plant resilience through multiple defense mechanisms while effectively managing spider mite infestations, offering a sustainable, eco-friendly alternative to synthetic pesticides in rose cultivation.