Clonal gametes enable polyploid genome design

[...]APH has been difficult to implement in plant breeding - despite evidence for it in maize, potato and alfalfa - because meiosis reassorts hybrid genotypes and genetically uniform seeds (which could benefit from additional heterosis) cannot be produced. [...]new routes to perform precise, polyploid genome design - the controlled combination of multiple pre-defined genome haplotypes - are needed to unleash heterosis in current and entirely novel polyploid crops. [...]we crossed hybrid MiMe plants that produce clonal gametes to generate '4-haplotype' plants that contained the complete grandparental genetic repertoire (Fig. la). The MiMe system we developed leads to reduced plant fertility owing to the incomplete penetrance of mutating SITAM for skipping the second meiotic division (a mixture of viable clonal gametes and non-viable gametes are produced). [...]it will be crucial to uncover novel ways for skipping meiosis II entry.