Unveiling the stimulatory effect of silicon nanoparticles on the direct regeneration and micro-structural developments in Cadaba trifoliata (Roxb.) Wight & Arn.

Abstract

Nanosilicon positively affects the growth and development of plants. Investigations were carried out to analyse the effect of applied silicon nanoparticles (SiNPs) on the multiplication and rooting of the shoots of Cadaba trifoliata (Capparaceae). In vitro-raised shoots were cultivated on Murashige and Skoog (MS) medium with 0.5 mg L⁻¹meta-Topolin (mT) and 0.25 mg L⁻¹ indole-3 acetic acid (IAA) along with various concentrations of SiNPs. 2.0 mg L⁻¹ nano-silicon along with optimal plant hormones improved multiplication of shoot numbers and morphology (25 shoots and 13.0 leaves per shoot), leaf area (1.3 × 0.9 cm), biomass (647 mg fresh weight; 114 mg dry weight) production, and photopigments (Chl a: 378.0, Chl b: 513.0, and C_x+c: 60.0 μg g⁻¹ fresh weight). Cent percent of the shoots were rooted in half-strength MS medium with 1.25 mg L⁻¹ indole-3-butyric acid (IBA). Incorporation of 2.0 mg L⁻¹ SiNPs in the medium promoted rooting (8.3 roots per shoot, each 4.93 cm long). Analyses of qualitative microscopic data revealed that the leaves developed from the cloned shoots exhibited well-organized stomatal guard cells and epidermal cells, thick cuticle and epidermis, and increased tissue density in mesophyll and vascular tissues. The stem and root anatomy revealed improvements in vascular tissue density and lignification in xylem vessels and phloem elements. The plantlets were acclimatized under ex vitro conditions for 8 weeks in soilrite and vermicompost mixtures. These findings highlight the potential of SiNPs in improving the regeneration potential for clonal propagation of C. trifoliata.