Reproductive biology of duodichogamous Koelreuteria elegans (Sapindaceae): the rare case of a female-male-female flowering sequence,

A. AVALOS; E.C. LATTAR; M.S. FERRUCCI; TORRETTA, JUAN PABLO

AUSTRALIAN JOURNAL OF BOTANY

CSIRO PUBLISHING

Lugar: Collingwood; Año: 2019 vol. 67 p. 149 - 158

0067-1924

Monoecious species are common within Sapindaceae and among them a large variation in sexual expression has been reported. In this work weevaluate the sexual expression, phenology, floral biology, and mating system in eight to sixteen individuals of the duodichogamous Koelreuteria elegans (Seem.) A.C. Sm.subsp. formosana (Hayata) F.G. Mey. Our results showed that all individuals exhibited a pattern of flowering characterized by two phases cycles of pistillate flowers with anintervening one of staminate flowers. The inflorescences presented ahigh synchronization between the male and female phases at the individual level. Therefore, very little functional overlap was observed between pollen receipt and pollen dispatch with inindividuals. Pollination was by bees, and the manual pollination experiments showed that this species is a xenogamous although self-compatible species. Nevertheless, seed set increased significantly with hand cross-pollination and open pollination experiments. Decrease of fruits and seeds set by geitonogamy could favor the establishment of duodichogamy with interfloral protogynypromoting cross-pollination. In the family this is the first report of a pattern of flowering in which there are two cycles of female with an intervening cycle of male flowers. The importance of detailed these studies for understanding mechanisms underlying duodichogamy was demonstrated. It could help to broaden our understanding about this rare sexual system to generalize the specific ecological factorsthat explain its evolutionary meaning.p { margin-bottom: 0.1in; line-height: 115%; }p { margin-bottom: 0.1in; line-height: 115%; }