Reproductive systems of Hammarbia paludosa (Orchidaceae)

POSTERS

reproductive biology 96

REPRODUCTIVE SYSTEMS OF HAMMARBIA PALUDOSA (ORCHIDACEAE) Elena A Bragina, Vladimir V Nazarov, Tatyana B Batygina (Komarov Botanical Institute, St Petersburg, Russia)

Many plants during the course of evolution have acquired the tendency to viviparity. The status of viviparity in flowering plant reproduction has been under discussion for a long time. Viviparity is certainly a special mode of reproduction, where dissemination is effected via diaspores (propagules) of different origin: generative - embryoviviparous (heterophasic): vegetative - embryoidoviviparous and gemmorhizogenous (homophasic reproduction). Viviparity (sensu lato) is the process of propagule formation on a plant via embryogenesis, embryoidogenesis, gemmorhizogenesis. It is an intermediate form between the typical seed reproduction and the typical vegetative propagation. The data on repboductive biology of the unique orchid Hammarbia paludosa, having propagules on the leaf margins are presented. Special attention was paid to the morphology and anatomy of the propagules. The propagule number on the leaves of different tiers varies. The correlation between propagule appearance and leaf age and time of generative shoot differentiation was established. The potential and actual seed productivity was estimated. Elena A Bragina, Department of Embryology and Reproductive Biology Komarov Botanical Institute Prof Popov Street 2 197376 St Petersburg

Russia

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