A special focus on Thottea from India

Speakers : Sandrine Isnard & Juliana Prosperi, UMR AMAP, Montpellier, France.

Piperales represent virtually the whole diversity of growth and life forms in angiosperms including herbs, shrubs, trees, parasites, epiphytes and climbers. This diversity is symptomatic for the success of Piperales in many ecosystems. Despite the importance of plant life and growth forms for ecosystem complexity and biodiversity, few studies have evaluated their evolutionary occurrence and patterns across major groups of angiosperms. This project aims at analyzing life and growth form evolution in the order Piperales, which represents the largest clade of basal angiosperms. The project will combine (i) functional biology with (ii) recent molecular phylogenetic approaches to study traits and their evolution in different lineages within Piperales.

This talk will present our sub-project on Aristolochiaceae, where we are interested in the evolution of growth forms and particularly in the evolution of treelets/shrubs within a family dominated by herbaceous and climbing forms. Self-supporting woody growth forms (treelets and shrubs) occur in two taxa within Aristolochiaceae, in the genus Thottea (southern Asia) and in Aristolochia subgenus Isotrema (in central America). The aims of this project on Thottea in Western Ghats are to describe the architecture of different species in the genus (from herbaceous to woody species) and to combine architectural method with biomechanical measurements on few specimens. We will present architectural and biomechanical method used to characterized growth form development.

Sur le site de l'Ifp.