Floral development in Hura crepitans L. (Euphorbiaceae)

Abstract

Euphorbiaceae, comprising 300 genera and about 6000 species, is considered a complex and morphologically diverse group having a large variety of habits and sorts of flowers and inflorescence. For this reason, the family has gone through a reassessment of his circumscription due to phylogenetic analyzes based on molecular data in recent years. The number of flowers per inflorescence in this group is quite varied and the position of the staminate and pistillate flowers, while in the same inflorescence, is also quite diverse. Based on these evolutionary changes of flowers, the objective of this study is to analyze the floral ontogeny, the activity of meristems and the modification of organs and whorls in Hura crepitans, and to investigate how these factors act in the formation of floral structures and in the inflorescence as a whole. Flower buds and flowers in various stages of development will be collected, fixed, dehydrated in alcohol series, embedded in paraffin, cut on a rotary microtome and blades will be stained according to conventional techniques. To assist in the investigation of floral ontogeny, will be held SEM analysis in the floral meristems and inflorescence. With this study is expected to understand the ontogeny of flowers in Hura crepitans and provide means for the understanding of phylogenetic relationships of Euphorbiaceae and patterns of development and diversification of the flowers in the family.