Biología floral de Passiflora foetida (Passifloraceae)

AMELA GARCÍA, M. T. & HOC, P. S.

REVISTA DE BIOLOGíA TROPICAL

Universidad Nacional de Costa Rica

Lugar: San José; Año: 1998 vol. 46 p. 9 - 20

0034-7744

A reproductive experiment shows that Passiflora foetida is self-compatible. Observations of floral characteristics and visitors during anthesis, plus the analysis of pollen allowed identification of floral syndrome (melittophily) and functions for each visitor. Anthesis occurs from 6 to 11 AM. Three floral phases were identified: 1) stigmas above anthers, 2) stigmas at anther level, 3) stigmas above anthers; radii, petals and sepals become incurved. The stigmas are receptive during the whole anthesis. The concentration of sugars in nectar is 34 %. The predominant color in the visible spectrum is white. The stamens and the gynoecium contrast against the limen and androgynophore in the UV spectrum, maybe a nectar guide. Three species of hymenopterans are the most frequent and constant visitors: Ptiloglossa tarsata (Colletidae) always contact the anthers and the stigmas while sucking nectar, carry a high percentage of P. foetida pollen and visit flowers in phases 1 and 2;  they can be considered the main pollinators. Pseudaugochloropsis sp. (Halictidae) rarely contact anthers and stigmas while puncturing the limen to access nectar, and visit flowers in phases 2 and 3; they are nectar robbers that rarely pollinate. Augochlorella sp. (Halictidae) collect pollen without touching the stigmas and visit flowers in phases 2 and 3; they are pollen thieves.