Summary
An allele or genotype is called protected if for all initial genotype frequencies positive it cannot be lost or does not remain at very low frequencies indefinitely. An analysis of protectedness was made for gynodioecious populations (populations with both female and hermaphrodite individuals) with four different types of one-locus two-allele models for the inheritance of gynodioecy. Ovule and pollen fertilities, together with selfing rates may differ between hermaphrodite genotypes. Such factors have not been considered previously, and lead to new conditions for the maintenance of the sex polymorphism. In particular, the mode of genetic control, and the hermaphrodite ovule and pollen fertilities, together with their selfing rates, may determine whether the female genotype is protected. Differential selfing among hermaphrodites may lead to overdominance and allow the maintenance of the polymorphism, and such differential selfing probably occurs in natural gynodioecious populations. In this connection the significance of models of inbreeding depression was considered.
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Gregorius, HR., Ross, M. & Gillet, E. Selection in plant populations of effectively infinite size: III. The maintenance of females among hermaphrodites for a biallelic model. Heredity 48, 329–343 (1982). https://doi.org/10.1038/hdy.1982.47
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DOI: https://doi.org/10.1038/hdy.1982.47
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