Plant Genome III Conference Plant Genome III Conference
About 350 random sequence 10-mer primers were screened against two DNA bulks from red- and yellow- fruited 'Rome Beauty' x'White Angel' progeny to identify markers linked to gene(s) for fruit color. One primer was found which generated two fragments present in the red fruit bulk and absent in die yellow fruit bulk. The smaller fragment (1160 bp) is from 'Rome Beauty' (Malus xdomestica) and the larger fragment (1180 bp) is from White Angel' (a Crab apple believed to derive from Asian species). Either one or two fragments are present in the red-fruited progeny. Another two fragments (1210 bp and 1230 bp) are found to be associated with yellow fruit. In three other crosses tested only the smaller fragment (1160 bp) cosegregated with red color. After cloning and sequencing the four fragments, we found that three of them (1160, 1180, and 1230 bp) displayed high sequence homology, while the other one (1210 bp) is totally different in sequence. The three homologous fragments were amplified successfully by designing two universal primers based on the sequencing information. The potential of these codominant DNA fragments in apple breeding and genetic studies will be discussed.