Abstract:
The purpose of this dissertation was to determine the reasons for the low seed set in D. eriantha. Aspects such as flower anthesis, pollen morphology, pollination, pollen viability, the morphology of the embryo sacs and seed set, were examined. While a high percentage of aborted pollen was found in the anthers, few problems exist in regard to pollen germination and viability. The reason for the low seed set in this species is probably to be found in the high percentage of sterile embryo sacs occurring here. This indicates a strong possibility of meiotic abnormality which may be related to the high percentage of aborted pollen in the anthers. On the strength of the 4-nucleate embryo sac found, it is also probable that facultative apomixis occurs in D. eriantha. An improved seed set could possibly be achieved by the use of clone selection and inbreeding.
