Ultrastructural aspects in the rhizome of Drosera Rotundifolia L. vitroplantules
Authors: Dorina CACHIŢĂ-COSMA1, Violeta TURCUŞ1, Constantin CRĂCIUN2
Affiliation: 1 “Vasile Goldiş” Western University, Arad, Romania, 2 Electron Microscopy Center, Babes-Bolyai University, Cluj-Napoca, Romania
ABSTRACT. The transmission electronic microscopy studies made on the Drosera rotundifolia L. vitroplantules – at cell and tissue level – allowed us point out the presence of some tissue elements in the stem, specific for the reserve parenchyma, in the present case in the rhizome, situated in the basal zone of the foils rosettes. In the cortex tissue cells of this organ, we have remarked rich starch deposits, the leucoplasts being transformed in starch cells. At the same time, we observed a significant difference between the sections made through the D. rotundifolia green vitroplantules rhizome, of which vacuoles were missing stains (both in the epidermis and the external bark cells), meanwhile in the vitroplantules with foil rosettes, red, the cell vacuom of most cells presented corpuscle like formations, strongly electron dense, or the entire vacuole mass appeared dark coloured. Experiments made previously by us, with different categories of phytoinculs (but also following cell researches made on divers epidermis of coloured petals), to which tissues were contrasted with osmic acid and uranil acetate, in vacuoles with antocians (leuco- or stains), their content was corpusculated, alike the phenomenon produced in the D. rotundifolia vitroplantules rhizome cell vacuoles, of red colour. Antocians, in the D. rotundifolia vitroplantules, are present not only in the leaf cell vacuom, but in the rhizome cells.
Keywords: D. rotundifolia vitrocultures, rhizome ultra-structure, starch corpuscle, antocians