Données sur le contexte végétatif lié à la floraison chez le cerisier (Prunus avium)

Abstract

A unique feature of Prunus avium L. is the distribution of growth between two types of morphologically and functionally distinct branches: auxiblasts and brachyblasts. The first ones are perennial and bear flowers at the basis of annual growth units. They are determinant for the architecture of the tree. The second type, born as lateral ramifications on the previous ones, have a much shorter life and support the flowers. A morphometric study was conducted on the growth units of the different types of ramifications in their primary phase of growth, on young and aged trees. It was showed that floral zones are characterized by a predominance of the foliar components over the stem components of the ramification. On the opposite, the vegetative zone of the auxiblasts is characterized by a predominance of the stem component. To designate these two phenomena, the terms "foliarization" and "axialization" were coined. With gradual aging of the tree and parallel evolution of the auxiblasts, toward progressively shorter as well as less and less ramified structures, an increasing preponderance of the leaves over the stem was observed or, to use the new terminology, a foliarization of the ramifications. In the meantimes, these become invaded by flowers. This type of morphometric study allows to describe simultaneously the progressive aging of the vegetative system along with the evolution of the distribution of flowering on different types of ramifications. Key words: architecture, morphometry, Prunus avium, aging, flowering. [Journal translation]