The effect of previous pollination on pollen tube growth of later deposited pollen in Hibiscus moscheutos.

Abstract

Two experimental treatments were performed on cut flowers of Hibiscus moscheutos to examine the effect of previous compatible pollination on the germination and pollen tube growth rate of a seconed load of compatible pollen applied three hours later. In both treatments, the first pollen load consisted of 30 grains of compatible pollen applied to half of one of the five stigmas per flower of H. moscheutos. In the first experimental treatment, the second pollen load was applied to the unpollinated half of the same stigma receiving the first load (Single-Stigma Treatment), and in the second experimental treatment, the second load was applied to a different stigma in the same flower (Separate-Stigma treatment). For each experimental treatment, pollen tube length of the late arriving pollen was compared to the growth of 30 grains deposited on flowers in which no previous pollination had occurred (Control Treatment). Paired t-tests indicated no differences in either pollen germination of pollen length after 2.25 hours between the experimental treatments and the Control.