EVIDENCE OF GENE INTROGRESSION IN APPLE USING RAPD MARKERS

A genomic remnant of Malus floribunda clone 821 introgressed into the cultivated apple M. x domestica Borkh. was identified using randomly a mplified polymorphic DNA (RAPD) markers obtained by the polymerase cha in reaction (PCR). Using a set of 59 oligonucleotide decamer primers, polymorphic DNA markers were identified among three pooled DNA samples . Based on the presence or absence of bands among bulked apple scab-re sistant selections and cultivars, bulked scab-susceptible cultivars, a nd a M. floribunda clone 821 sample, one primer, A15, identified ampli fied fragments in the scab-resistant bulked sample that was also uniqu e to the M. floribunda clone 821. The unique band from M. floribunda c lone 821 was amplified in four out of 17 scab-resistant selections/cul tivars. This RAPD, designated OA15(900), identifies an introgressed fr agment that has as yet no known function.