Temporal Variation in Pollen Limitation of Montane Wildflower Individuals
PublisherThe University of Arizona.
RightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
AbstractPlant reproduction is highly dependent upon phenology, or biological timing, of flowering. However, little is known about how individuals vary in their flowering schedules relative to the population as a whole or how this variation could lead to differences in reproductive success of individuals. Here, it was shown that individuals of three species of montane wildflowers (Hydrophyllum fendleri, Boraginaceae; Linum lewisii, Linaceae; and Potentilla gracilis, Rosaceae) were aggregated in time. However, Hydrophyllum and Potentilla individuals that flowered later in the season matured a higher proportion of fruits while Linum individuals that flowered earlier had a higher reproductive success. I tested the hypothesis that pollen limitation was responsible for the temporal variation in reproduction observed in these species. It was found that Linum individuals are not pollen limited at any time throughout the season, Hydrophyllum individuals are pollen limited but the amount does not vary with time, and Potentilla individuals are more pollen limited at the beginning of the season. These results show that pollen limitation and reproduction vary significantly between species and within species, and therefore phenology of plants at the individual level plays an important role in ecological dynamics.
Degree ProgramHonors College
Ecology and Evolutionary Biology