FIGURE 1.

From the formation toward the complete diploidization of polyploids: insights of meiotic pairing and recombination. Auto- and allotetraploids can be formed via many routes, which may involve intermediates (e.g., triploids and amphihaploids). While pairing and recombination are initially perturbed, as represented by multiple/illegitimate associations and by increasing number of crossovers, a diploid-like meiosis is setting up through a strict regulation of meiotic recombination, a process referred as partial diploidization. Following millions of years, diploidization becomes complete through a return at a diploid stage resulting in a chromosome number reduction. On this figure, insights of pairing and recombination mostly based on research performed in Arabidopsis, Brassica, Lolium, and Phlox genera are presented. Within each pollen mother cell drawn, the chromosomes of the same size and same color derive from the same species, while those of different colors derive from two different species.