Abstract: In this study , an AFLP marker of Co gene of apple was converted into a SCAR marker successfully. After sequencing of the AFLP marker fragment , two pairs of primers CoA1/ CoA2 and CoA1/ CoA3 were designed according to the nucleotide sequence. PCR results from apple genomic DNA showed that CoA1/ CoA2 could amplify two bands with the size of 216bp and 148bp respectively , and the one of 216bp was the character band of columnar phenotype ; CoA1/ CoA3 could amplified two bands too , and the size was 273bp and 205bp respectively , the former one was the character band of columnar phenotype. Both of the two pairs of primers have high correct rate in judgment of columnar growth habit ( > 90 %) , so either of them can be served as special primers of this SCAR marker for rapid selection.

Key words: Apple, Columnar gene (Co), AFLP marker, SCAR marker