Comparative genome mapping between apple and pear by apple mapped SSR markers.

摘要

Twenty nine apple-mapped SSRs were screened out to construct pear segment map of 'Mishirazi' (Pyrus pyrifolia x P. communis) x 'Jinhua' (P. bretschneideri). Synteny between apple and pear was adopted to conclude the linkage group number. The 'Jinhua' was primary taken as representative Chinese pear to compare genetic map of apple and European pear (P. communis), Japanese pear (P. pyrifolia) and Chinese pear (P. bretschneideri). The alignment of the species maps based on JoinMap analysis made it possible to verify the degree of synteny between the apple and pear genomes. The apple SSR loci showed the same order and corresponding distances in the pear and apple maps, strongly suggesting the presence of highly conserved regions between the two genomes and that apple SSRs were more preferable to transfer and conserve to European pears than Asian pears. The most conserved segments of linkage group between apple and pear were located in LG 9, LG 11 and LG 14 relying on 101 apple-mapped SSRs. The SSRs in LG 10 and 12 wouldn't like to link each other in the cultivar of P. bretschneideri in China and P. pyrifolia in Japan, respectively.