Intraspecific Variation in Pollen-Ovule Ratios and Nectar Secretion- Preliminary Evidence of Ecotypic Adaptation

Abstract

Because pollen-ovule ratios (P/O's) reflect the predictability of pollinators in a habitat and the efficiency of pollination, large intraspecific differences in P/O's suggest differences in pollinator numbers and/or their efficiency.Plants of Heracleum lanatum, which is andromonoecious, from forests have larger percentages of male flowers than those outside of forests, hence a higher P/O.This difference is associated with differences in the kinds of flower visitors.I