Gynoecial anatomy and development in Cyperoideae (Cyperaceae, Poales): congenital fusion of carpels facilitates evolutionary modifications in pistil structure
Reynders, Marc × Vrijdaghs, Alexander Larridon, Isabel Huygh, Wim Leroux, Olivier Muasya, A. Muthama Goetghebeur, Paul #
Royal Botanical Society of Belgium
Plant Ecology and Evolution vol:145 issue:1 pages:96-125
Background and aims - In Cyperaceae, the single-ovuled, usually triangular gynoecia are widely considered to have a basic number of three carpels, often reduced to two, resulting in dimerous pistils. However, laterally flattened dimerous pistils cannot be explained by any existing carpel reduction theories, because a single stigma in median position replaces the two adaxial stigmata. This paper presents a comparative study of the ontogenetic and anatomical adaptations facilitating the origin of new pistil forms in Cyperoideae, focusing on modified gynoecia. It includes a re-evaluation of Blaser's (1941) anatomical studies in Cyperaceae. We aim to test Blaser's hypothesis that is based on an acropetal developmental model of the floral vasculature and the general Cyperoid ontogenetic model of Vrijdaghs et al. (2009), which states that cyperoid ovaries originate from an annular primordium.