Inflorescence Structure in Primitive Angiosperms

Abstract

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Estructura, ontogenia y vascularización de las flores e inflorescencias de Drimys granadensis (Winteraceae)

“…En Drimys las inflorescencias han sido tradicionalmente consideradas como monotélicas proliferantes (Weberling, 1988) o monotélicas truncadas (Weberling, 1992). La condición proliferante o truncada implica que el eje principal del sistema inflorescencial culmina en un meristema que luego de la floración retoma el crecimiento vegetativo.…”

“…La presencia en D. granadensis de uniflorescencias con flores terminales diferentes a las laterales (por ser ebracteadas y más simétricas), sumado a su desarrollo acrópeto podría tener una explicación alternativa a la propuesta por Weberling (1988;1992) : Sokoloff, Rudall, & Remizowa (2006) proponen tres posibles tipos de estructura terminal en las inflorescencias: (a) una verdadera flor terminal, (b) un pseudanto por unión de flores laterales y (c) una flor lateral que ha cambiado a posición pseudoterminal. En Drimys, varios criterios señalados por Sokoloff et al (2006) apuntan a que se presenta una verdadera flor terminal: (1) aunque su origen es tardío (desarrollo acrópeto), sufre antesis antes que las flores laterales superiores, (2) carece de bractea (varias brácteas indicarían Q.).…”

“…con crecimiento simpodial debido a la presencia de inflorescencias terminales (vink, 1993) y Drimys, Pseudowintera y Tasmannia con crecimiento monopodial, debido a la proliferación del eje inflorescencial en los dos primeros géneros (Weberling, 1988); o a la presencia de inflorescencias caulifloras en Tasmannia (Sampson, 1963;vink, 1970).…”

“…Forst. : vascularización (Nast, 1944), estructura (Weberling, 1988), ontogenia de flores e inflorescencias (Tucker, 1959;vink, 1970;Doust, 2001).…”

“…Con el fin de unificar terminología, en esta investigación los términos inflorescencia y uniflorescencia son utilizados en el sentido de Doust (2001 ; Fig. 1A); por lo tanto, inflorescencia es equivalente a rama inflorescencial (sensu Tucker, 1959) y uniflorescencia equivale a inflorescencia sensu Nast (1944) y Tucker (1959 o a paracladio sensu Weberling (1988).…”