Homoeologous Heterozygosity and Recombination in the Fern Pteridium aquilinum

Abstract
The bracken fern, Pteridium aquilinum, which can form completely homozygous zygotes in a single generation of self-fertilization, has a genetic system that allows the storage and release of genetic variability in spite of this homozygosity. Analysis of the distribution of electrophoretically demonstrable genetic markers demonstrates that this system is based on recombination between duplicated, unlinked loci.