Data from: Who determines the timing of inflorescence closure of a sexual dandelion?: Pollen donors vs. recipients

Male-male competition for mating or fertilization opportunities may in
theory select for male manipulative adaptation that can harm males’ mates,
leading to sexual conflict. Evolutionary theory predicts that selection
will favor the manipulation by pollen of the duration of its recipients’
receptivity. However, there is insufficient evidence to show that pollen
can exert effects on the duration of receptivity, a prerequisite for the
evolution of pollen manipulative adaptation. Using a sexual diploid
dandelion, Taraxacum japonicum, we conducted hand pollination experiments
within and between populations to examine the effects of pollen on the
timing of inflorescence (flower head) closure. We also examined the
potential fitness consequences to the pollen recipients by field
observation of seed production in populations with different inflorescence
closure timing. Within-population experiments showed that pollination
induced inflorescence closure even when some of the florets in the
inflorescence were not yet pollinated with compatible pollen. Furthermore,
between-population crosses revealed that pollen donors, recipients, and
their interaction all influenced the timing of inflorescence closure.
Different populations differed in the timing of inflorescence closure,
which could affect the availability to the recipients of pollen for
fertilization and thereby seed production. However, there were no
significant differences in the rates of natural seed production in these
populations. Our results demonstrate that pollen donors, as well as
recipients, contribute to the duration of floral receptivity, confirming
that a prerequisite for sexually antagonistic adaptation is satisfied and
suggesting manipulative adaptation of pollen or its donor. We discuss the
implications of our findings to the evolutionary theory of plant
reproduction.