Osmotic pretreatment promotes axillary shooting from cauliflower curd pieces by acting through internal cytokinin level modifications

• Published in: Journal of plant physiology Vol. 158; no. 2; pp. 221 - 225
• Main Authors: Vandemoortele, Jean-Luc, Kevers, Claire, Billard, Jean-Pierre, Gaspar, Thomas
• Format: Journal Article Web Resource
• Language: English
• Published: Jena Elsevier GmbH 2001; Elsevier; Urban & Fischer
• Subjects: acclimatization; Agronomy. Soil science and plant productions; Biological and medical sciences; Biologie végétale (sciences végétales, sylviculture, mycologie...); Biotechnology; Brassica oleracea L. var botrytis; Economic plant physiology; Fundamental and applied biological sciences. Psychology; In vitro culture; Life Sciences; micropropagation; Phytobiology (plant sciences, forestry, mycology...); Phytopathology and phytopharmacy; Plant physiology and development; Sciences du vivant; sucrose; Tissue cultures, protoplasts; Vegetal Biology; zeatin; zeatin riboside; zeatin riboside; Brassica oleracea L. var. botrytis; acclimatization; sucrose; micropropagation; zeatin; Brassica oleracea var. botrytis; Culture medium; Auxin; Tissue culture; Micropropagation; Growth regulator treatment; Cytokinin; Morphogenesis; Vegetable crop; Cruciferae; Dicotyledones; Angiospermae; Plant growth substance; Above ground plant part; Spermatophyta; Hyperhydration; Osmotic pressure
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1078/0176-1617-00197

In vitro propagation of cauliflower has generally been achieved through axillary shoot proliferation of curd explants on Murashige and Skoog (MS) medium supplemented with an auxin and a cytokinin. Recently, it has been shown (Vandemoortele 1999) that a soaking in sucrose (-2 MPa for 24 h) of cauliflower curd explants, before culture without any growth regulator, also induced axillary branching. The later procedure avoids the phenomenon of hyperhydricity in the shoots formed. Axillary shooting obtained by the two methods appears to be mediated by modifications of internal cytokinin levels. The osmotic pretreatment did not influence auxin levels, but induced a zeatin and a zeatin riboside levels increase. Curd explants cultured with the usual procedure (on MS medium supplemented with 5 μmol/L BA and 0.5 μmol/L NAA) showed a zeatin and zeatin riboside levels increase of the same magnitude and a higher one for isopentenyl adenine and isopentenyl adenosine. The modification of the cytokinin status in the curd explants subjected to a short osmotic pretreatment thus should be less favourable for hyperhydricity.