Potato Breeding through Ploidy Manipulations

The cultivated potato (Solanum tuberosum L.) is a clonally propagated autotetraploid (2n = 4x = 48) that represents the third most important crop in the world. Breeding e orts are complicated by some typical genetic features including, among the others, tetrasomic inheritance, chromatid segregation, high levels of heterozygosity and multiple allelism. However, unique reproductive characteristics of cultivated and wild potatoes may facilitate breeders’ work: the production of 2n gametes; the presence of an endosperm dosage system that predicts success of interspeci c crosses; the possibility to easily extract haploids. After illustrating the genetics and reproductive characteristics of this important autotetraploid and the signi cance of its wild relatives, our chapter describes main breeding targets and reviews results obtained in manipulating whole chromosome sets, from the monoploid to the hexaploid level. Finally, the perspectives of molecular breeding are discussed.