Abstract
BACKGROUND AND OBJECTIVE: Recently, silicon (Si) has been demonstrated to be an important element in agriculture. Its significance in plant growth has prompted numerous studies. However, the knowledge about its role in plant tissue cultures is still limited. In an attempt to understand the role and effect of silicon on plant growth, morphologically and physiologically, in vitro, regenerated fig (Ficus carica var. Sultany) was used to study this purpose. MATERIALS AND METHODS: Silicon as potassium silicate (K(2)O.4SiO(2); PS) was added to the MS medium at 0 (PS0), 0.1 (PS1), 1.0 (PS2), and 10.0 (PS3) mg L(- 1). After four subcultures, morphological measurements and contents of element compounds, including N, P, K, Na, Ca, Fe, Mn, Zn, Cu, Ni, Cr, Cd, Pb, and As, were determined in treated shoots, high-performance liquid chromatography (HPLC) was used to identify and quantify phenolic compounds, total phenolic, and flavonoid contents, while free radical scavenging activities were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. RESULTS: Results showed that adding silicate at 1.0 mg L(- 1) enhanced shoot number, leaf number, chlorophyll, growth vigour, leaf area, fresh and dry weight, and significantly reduced vitrification. Nineteen compounds were identified, with fig shoot extracts showing significant variation in the contents of phenolic acids and flavonoids. CONCLUSION: The use of potassium silicate enhanced fig growth, elemental content, and pharmacological components; however, a high rate (10.0 mg L(- 1)) diminished most parameters, with the exception of Na and Cr. Further studies using low rates of traditional and nanoparticles of silicate are recommended.