Summary: | Within the Cape Floristic Region many lineages are characterised by large floral diversity. The genus Erica is one of these lineages, making up -7% of the CFR. Surprisingly, even though pollinators have been suggested to be a driving force of floral morphology, the role of pollinators in the floral diversification and speciation of this genus is not yet well understood. Therefore the aim of this paper was to establish if Erica species can and do self-pollinate. Two Erica species, E. plukenetii and E. urnaviridis, were obtained from Kirstenbosch nursery, where hand-pollinations were performed on 15-20 flowers of each of three treatments (self-pollination, crosspollination and autogamous self-pollination. Additionally pollen tube analyses were performed on seven Erica species, which were collected from the Constantia Mountain. In E. plukenetii, self-incompatibility seems to be the predominant breeding system. It appears that, like E. urna-viridis, most of the other species analysed, via pollen tube analyses, have the potential to self-pollinate. However, more experiments are required to establish if these species are truly self-compatible. Autogamy, on the other hand, does not appear to set seed in the species studied. Therefore it would be fair to say that some ericas can self-pollinate but none actually do self-pollinate. These results indicate that ericas have a strong dependence on pollinators for seed set and in the past speciation may have occurred due to adaptation to different pollinators, when opllinators were scarce.
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