Carpellary appendages in Nymphaea and Victoria (Nymphaeaceae): evidence of their role as osmophores based on morphology, anatomy and ultrastructure

ZINI, L. M.; GALATI, B. G.; GOTELLI, M. M.; ZARLAVZKY, G; FERRUCCI, M. S

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2019 vol. 191

0024-4074

Inflowers of Nymphaea and Victoria, carpellary appendages areregarded as structures related to pollination by deceit of night-bloomingspecies. In this study, the anatomy,histochemistry and ultrastructureof carpellary appendages were analyzed to investigate their possible role inthe production of volatile compounds in nocturnalspeciesNymphaea amazonum, N. gardneriana, N. proliferaof the subgenus Hydrocallis, and Victoria cruziana, and in diurnal species N. caerulea of the subgenus Brachyceras. Carpellary appendages are analyzed under light microscopy, andscanning and transmission electron microscopy from pre-anthesis to the secondday of anthesis. Anatomical and ultrastructural features are characteristic ofosmophores. In all species, the most frequent components in secretory cells areamyloplasts, lipid bodies, mitochondria, rough endoplasmic reticulum, andelaioplasts. The epidermis and multilayered parenchymaaccumulate abundant starch grains and lipophilic substances, both of whichvanish during anthesis. Amorphous substances are deposited between plasmalemmaand the outer cell wall of epidermal cells, and are then released by cuticulardiffusion. Odor production incarpellary appendages might be an ancient role of primary importance both indiurnal and nocturnal species that are pollinated by deceit. Olfactory andvisual cues of small carpellary appendages in subgenus Brachyceras correspond to beepollination, and large carpellary appendages in subgenus Hydrocallis and in Victoria representparallel functional specializations of the flowers to the attraction and rewardfor the exclusive beetle pollination.