Development of dichotomous branching and axillary buds in Strelitzia (Monocotyledoneae)

Abstract

The morphology and development of branches and inflorescence buds in two species of Strelitzia are described and illustrated. Axillary buds develop similarly in each species, producing both inflorescences and suckers in the caulescent S. nicolai and only inflorescences in the acaulescent S. reginae. Bud initiation occurs in the axil of the first or second leaf primordium. A well developed shell zone is present. Branching in S. reginae occurs by the division of the apical dome above the first leaf primordium and is considered a true dichotomy. Fasciation occurs in 37% of leaves enclosing the two new shoots in S. reginae. It is concluded that dichotomous branching should not be interpreted as a phylogenetically primitive character in the monocotyledons.