Biotechnologie, Agronomie, Société et Environnement (Jan 2002)
Processus de développement génératif chez le pommier cv Golden Delicious
Abstract
Generative development process of apple cv Golden Delicious. The meristem organogenesis of the ""bourse"" shoot, the morphologic and the histologic modifications were studied at the end of the growth stopping by means of histological techniques, microdissections of the apex and observations by scanning electron microscopy. These modifications are linked to the transition of the meristem from vegetative to flowering stage. The acquisition of the reproductive stage by the apical meristem occurs progressively in 2 phases : A vegetative phase during which the apical meristem begins to form the terminal bud where floral differentiation occur. The presence of a number of structures is necessary before the first sign of floral transition appears within the apex of the ""bourse"" shoot. A floral differentiation phase which begins by the swelling of the ""bourse"" shoot apical meristem at the end of July for short shoots and one month later for long shoots. This apex will produce at the same time vegetative (bourse bud, leaf primordial, scale) and generative (terminal and lateral flowers) structures.
