October 2009 to present, collaborative research project

To understand better the polyphyletic nature of the genus Hydrangea and its close relationship with eight other genera, we have been working towards resolution of the relationships within the tribe Hydrangeeae, including the genera Broussaisia, Cardiandra, Decumaria, Deinanthe, Dichroa, Hydrangea, Pileostegia, Platycrater and Schizophragma. Consequently, we focus on the relationships between and within the sections, subsections, botanical species and infraspecific taxa of Hydrangea s.s., based on micromorphological, anatomical and molecular studies of an extensive sampling and with the revision of McClintock (1957) as starting reference.

An especially poorly know group within Hydrangea s.s. is section Cornidia consisting of root-climbing species in Latin America. The section currently consists of about 12 accepted species, but our field and herbarium work has shown incorrect synonimization and revealed many species yet unknown to science. For more information, see the Hydrangea section Cornidia webpage.

Representatives of section Cornidia are being used to obtain an insight in the evolution of growth forms in the tribe Hydrangeeae by biomechanical and anatomical studies. The lianous growth form is unique in the order Cornales and has several times independently evolved within Hydrangeeae, namely in Hydrangea section Cornidia and in the genera Pileostegia, Decumaria en Schizophragma. Based on this study, evolutionary trends in growth forms in the order Cornales will be proposed in a phylogenetic framework.

Combination of morphological and molecular studies will act as a starting point for a better understanding of the parallel evolution of the conspicuous morphological characters on which the classification of the tribe Hydrangeeae is currently based. In addition, we will recircumscribe the existing genera in the tribe as well as define new monophyletic groups previously classified in paraphyletic genera. This will be the basis for a new classification reflecting the phylogenetic relationships and interpreting the observed biomechanical, morphological and anatomical characters in a molecular framework.
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Relevant publication:
Samain MS, Wanke S, Goetghebeur P. (2010) Unraveling extensive paraphyly in the genus Hydrangea s.l. with implications for the systematics of tribe Hydrangeeae. Systematic Botany 35: 593-600.

Principal investigator:
Prof. Dr. Marie-Stéphanie Samain

Associated researchers:
Dr. Carolina Granados Mendoza - Instituto de Biología, UNAM, Mexico
Drs. Yannick De Smet

Laboratory technician:
Pieter Asselman

Prof. Dr. Paul Goetghebeur

Dr. Stefan Wanke - TU Dresden, Germany

Dr. Nick Rowe - CNRS (Centre National de la Recherche Scientifique), UMR AMAP, Montpellier, France
Dr. Sandrine Isnard - IRD (Institut de Recherche pour le Développement), UMR AMAP, New Caledonia

BOF (Special Research Fund) PhD research grant (n° 01J03309)

Research Foundation Flanders PhD grant (project n° 1151811N) & international mobility grants

King Léopold III Foundation for the Exploration and Protection of Nature international mobility grant

TU Dresden, Biology Department, Germany (grant for lab work performed at the TU Dresden)
BMBF (Bundesministeriums für Bildung und Forschung) - KMU-innovativ 9: Biotechnologie - BioChance, Germany (grant to German partner)

COMECYT (Consejo Mexiquense de Ciencia y Tecnología), Mexico

Ghent University
Department of Biology
Research Group Spermatophytes
Ghent University Botanical Garden