Genetic linkage maps of two apricot cultivars (Prunus armeniaca L.) compared with the almond Texas × peach Earlygold reference map for Prunus

• Published in: Theoretical and applied genetics 2004-04, Vol.108 (6), p.1120-1130
• Main Authors: Lambert, P, Hagen, L. S, Arus, P, Audergon, J. M
• Format: Article
• Language: English
• Subjects: Cultivars; DNA probes; Gene mapping; Genetic crosses; Genetic linkage; Genetics; Genomes; Homology; Hybrids; Progeny; Prunus; Simple sequence repeats; Species
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s00122-003-1526-3

Several genetic linkage maps have been published in recent years on different Prunus species suggesting a high level of resemblance among the genomes of these species. One of these maps (Joobeur et al., Theor Appl Genet 97:1034–1041 [(1998); Aranzana et al., Theor Appl Genet 106:819–825 (2002b)] constructed from interspecific almond Texas × peach Earlygold F₂ progeny (T×E) was considered to be saturated. We selected 142 F₁ apricot hybrids obtained from a cross between P. armeniaca cvs. Polonais and Stark Early Orange for mapping. Eighty-eight RFLP probes and 20 peach SSR primer pairs used for the ‘reference map’ were selected to cover the eight linkage groups. One P. davidiana and an additional 14 apricot simple sequence repeats (SSRs) were mapped for the F₁ progeny. Eighty-three amplified fragment length polymorphisms were added in order to increase the density of the maps. Separate maps were made for each parent according to the ‘double pseudo-testcross’ model of analysis. A total of 141 markers were placed on the map of Stark Early Orange, defining a total length of 699 cM, and 110 markers were placed on the map of Polonais, defining a total length of 538 cM. Twenty-one SSRs and 18 restriction placed in the T×E map were heterozygous in both parents (anchor loci), thereby enabling the alignment of the eight homologous linkage groups of each map. Except for 15 markers, most markers present in each linkage group in apricot were aligned with those in T×E map, indicating a high degree of colinearity between the apricot genome and the peach and almond genomes. These results suggest a strong homology of the genomes between these species and probably between Prunophora and Amygdalus sub-genera.