Silicon in the Embriogenic Potential of Callus in vitro of Passiflora edulis

Adding silicon to the culture medium may contribute, to improve many growth parameters including embryogenesis and organogenesis. The objective of this study was to evaluate the embryogenic potential of passion fruit in vitro (Passiflora edulis f. Flavicarpa O. Deg), submitted to different concentrations of silicon. Nodal segments of plants were inoculated at five concentrations of silicic acid added to the culture medium, 0.0; 0.5; 1.0; 1.5 and 2.0 g L-1. After 60 days, the visual characteristics (% contamination, callus, bud, root and oxidation), cytochemical test and microanalysis of X-rays evaluated. Concentrations of 0.5; 1.0 and 2.0 g L-1 of silicon did not differ in relation to callus formation. By the cytochemical test, all treatments presented embryogenic cells indicated by the reaction to acetic Carmine and, little reaction to the Evans blue associated with cell death. By the microanalysis of X-rays, the nutrients sulfur and phosphorus, presented significant absorption responses at the concentration of 1.5 g L-1 of silicon in comparison to the other concentrations. The silicon added to the culture medium has a response in the formation of cells with embryogenic potential in nodal segments of passion fruit. The concentration of 2.0 g L-1 of silicon acid (H4SiO4) has a high embryogenic potential in passionflower cells, Passiflora edulis f. Flavicarpa O. Deg.