Research Training Program

Smithsonian Institution
National Museum of Natural History

PROJECT SUMMARY
1996

Fabiola Areces
Universidad de la Habana
Ciudad Habana, Cuba
Joan W. Nowicke, Ph.D.
Supervising Scientist
Department of Botany
"The experience that I received at the Palynology laboratory was one I could never have had without the Smithsonian Research Training Program and I'm grateful to have been a part of it."

Preliminary examination of pollen of Passiflora

ABSTRACT
Passifloraceae is a medium-sized family, comprising 20 genera and approximately 600 species native to the tropics and subtropics. The largest genus is Passiflora which has almost 450 species in the warmer parts of America and few species in Asia. Previous studies of the pollen have been based mostly on Light Microscopy (LM) and occasionally SEM. The pollen of 10 taxa of Passiflora, Adenia hastata and Tetrapathaea tetrandra were examined in LM, SEM and selected species in TEM. All taxa examined had a variously reticulate tectum. Within the ten taxa of Passiflora, two pollen types, both of which are thick walled, can be recognized: I. Pollen is 6-zonocolporate with fusiform opercula, and lacks free columellae in the lumina (not examined in TEM ); II. Pollen could be interpreted as 3-colpate with very large ovate opercula, has free columellae in lumina, a massive endexine and lacks foot layer. Pollen of Adenia hastata is thin walled, 5-6 zonocolpate, and lacks opercula. Pollen of Tetrapathaea tetranda is thin walled, 3-colpate with strap-shaped opercula, lacks free columellae, has prominent endexine only under aperture and has a foot layer. The four pollen types described above can be easily distinguished from each other even in LM. This study is one of the first attempts to document the structure of the exine of Passiflora using TEM.

This research was supported by a grant from the James Smithson Society.

Letter of Gratitude