© 1994 Heron Publishing—Victoria, Canada
Endogenous polyamine concentrations in juvenile, adult and in vitro reinvigorated hazel
Manuel Rey (1, 2), Antonio F. Tiburcio (3), Carmen Díaz-Sala (1, 4) and Roberto Rodríguez (1)
1. Laboratorio de Fisiología Vegetal, Departamento Biología de Organismos y Sistemas, Universidad de Oviedo, 33005 Oviedo, Spain / 2. Divisione Ingegneria Genetica (026), Settore Agricoltura e Biotecnologie, Dipartimento Innovazione, ENEA - C.R.E. Casaccia,
C.P. 2400, 00100 Roma A.D., Italy / 3. Laboratori de Fisiologia Vegetal, Facultat de Farmàcia, Universitat de Barcelona, 08028 Barcelona, Spain / 4. Department of Forest Biology, University of Maine, Orono, Maine 04469, USA / Received April 8, 1993
Summary
We investigated endogenous polyamine concentrations in leaves from juvenile and mature hazel (Corylus avellana L.) shoots, as well as leaves from shoots obtained by both forced outgrowth and micropropagation of adult tissues. To determine
if the observed in vitro reinvigoration was associated with polyamine metabolism, we tested the effect of serial subcultures
on polyamine concentrations. Polyamines, mostly free putrescine, were higher in juvenile tissues. Adult tissues micropropagated
for 14 subcultures had polyamine concentrations characteristic of juvenile tissues. However, with additional subcultures,
total polyamine concentrations decreased. The putrescine to spermidine plus spermine ratio was higher in juvenile and micropropagated
tissues than in adult tissues, but decreased in micropropagated tissues after 20 subcultures. This ratio may reflect a balance
between vegetative growth and reproductive processes. Thus, an analysis of polyamine concentrations may provide a simple assay
for determining the juvenility of plant tissues and, hence, their suitability for micropropagation.
Keywords:
micropropagation, morphogenetic potential, putrescine, spermidine, spermine, subculture.
