Abstract
Inbreeding in homosporous plants, unlike angiosperms, can consist of two potential components: (1) fusion of gametes from the same gametophyte (intragametophytic selfing) and (2) matings between different gametophyte of the same parent (intergametophytic selfing). Although some workers maintain that intragametophytic selfing predominates in these populations, no attempt has been made to evaluate these two components of inbreeding in natural populations of homosporous ferns or lycopods. This paper gives a method for joint estimation of these two selfing rates, which uses data from two unlinked loci and makes the assumption of inbreeding equilibrium. The procedure was used to estimate selfing rates in six populations of two fern species. Weakly significant levels of intergametophytic selfing were found in one population of each species. The validity of the assumption of inbreeding equilibrium is discussed, and the requirement for several polymorphic marker loci is emphasized.
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Ritland, K., Soltis, D. & Soltis, P. A two-locus model for the joint estimation of intergametophytic and intragametophytic selfing rates. Heredity 65, 289–296 (1990). https://doi.org/10.1038/hdy.1990.98
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DOI: https://doi.org/10.1038/hdy.1990.98
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