Polyploidy and Evolution in Plants

Summary Polyploidy played a significant role in the origin and evolution of many plant species. The primary phylogenetic effect of polyploidy is to stabilize selected hybrid genotypes. It also provides a mechanism by which daughter and parental populations become immediately isolated from each other. Isolation, however, is rarely complete, and introgression commonly takes place across partially sterile hybrids. Polyploidy also buffers genotypes against the shock of absorbing foreign genomes, making hybridization possible between species that are otherwise genetically isolated from each other. Traditional taxonomy can usually not adequately indicate the extent of variability that characterize polyploid complexes.