Comparative mapping of Prunus armeniaca, Prunus cerasifera x Prunus armeniaca and Prunus reference map

Apricot and plum x apricot genetic linkage maps were constructed taking as a reference the almond 'Texas' x peach 'Earlygold' map (Joobeur et al., 1998; Aranzana et al., 2003) named IT x V. The apricot mapping population was an intraspecific cross between 'Polonais' and 'Stark Early Orange'. The plum x apricot mapping population (P xdasycarpa) was issued from an interspecific cross between Myrobalan plum (Prunus cerasifera Ehrh.) and apricot (Prunus armeniaca L.). The apricot parent (A3923) was a hybrid between 'Screara' and 'Stark Early Orange' (clone A669). These populations are part of breeding programs which aim at creating new genotypes combining several important traits: mainly fruit quality traits and disease resistance including sharka for apricot cultivars, graft compatibility, and pest and disease resistance for rootstocks. Apricot and Myrobalan maps were constructed by selecting a set of codominant markers on the 'T x E' map and by adding dominant markers. A total of 232 markers were distributed in the Myrobalan and apricot 'A3923' maps and 251 in the integrated apricot map ('P x S'). A set of common markers allowed anchoring of the 8 groups of the apricot maps ('P x S' and 'A3923') and 6 groups of the Myrobalan map to the homologous groups of the IT x El map and displayed a good colinearity. The remaining linkage group of the Myrobalan map was found to be composed of two linkage groups of the reference map.