Position et orientation des mitoses dans la zone organogène de jeunes feuilles de Fraxinus excelsior, Glechoma hederacea et Lycopus europaeus

Abstract

Whether the leaf is simple (Lycopus, Glechoma) or compound (Fraximus), pinnate (Lycopus, Fraximus) or palmate (Glechoma) in its nervation or leaflet arrangement, and acropetal (Fraximus) or basipetal (Lycopus, Glechoma) in its development, the organogenetic zone of its primordium is characterized by a continuum of meristematic activity, a submarginal optimum mitotic density, a mitotic polarity (the main cause of lobation) and a very important individual variability.