Structure and ontogeny of inflorescence and flower of Bactris simplicifrons Mart. (Arecaceae, Arecoideae, Bactridinae)

Abstract

Abstract The paper investigates the ontogeny and morphoanatomy of flowers and inflorescences of Bactris simplicifrons Mart. The objective was to provide useful biological information and add features that may be of interest in the taxonomy of the genus. To achieve this, we use light and scanning electron microscopy. The ontogenetic study reveals the acropetal development of the inflorescences, as well as the formation of one subtending bract for each flower of the triad and one for each triad, the latter being connate. Similarly, the sequence of centripetal development of the flower parts and the formation of the gynoecium were evident, synascidiate at the base, symplicate at the top and assimplicate at the apex. Additionally, the histological arrangement of each floral organ was characterized and all the appendages observed were described. The characters of possible diagnostic value are: length of stigmatic lobes, indumentum and morphology of trichomes, absence of rigid emergence, content of phenolic compounds, morphology of the staminal filament, among others.