Apple(Malus domestica Borka) is one of the most important fruit crops in the world, by long evolution, the gentic variability within each species is very abundant. In this study, mutants of cultivar‘Red Delicious’and‘Fuji’are test targets,and we carried out some works: establishment of the IRAP-PCR reaction system in Malus genus;construction of fingerprint in cultivar‘Red Delicious’and‘Fuji’, primary sport identifyication;a special fragment was generated with ARL5 primer, two primers were designed b...