Abstract:Allozymic variation of 113 loquate cultivars of Eriobotrya japonica Lindl.and 4 wild related species(E.prinoides Rehd.et Wils.,E.prinoides var.danduheensis H.Z.Zhang,E.serrata Vidal.and E.dayaoshanensis Chen) were investigated using isoelectric focuses in thin-layer po-(lyacrylamide) slab gel in present study.Fifty-nine alleles of 24 loci in 12 enzyme systems were detected 21 loci are polymorphic.The maxium number of alleles in a locus is five.The result demonstrated a rich genetic diversity in loquat germplasm.χ2 tests for homogeneity of allele frequencies across different cultivar groups revealved 15 of 19 ploymorphic loci are significant different among the groups.Moreover,some specific alleles were detected in different species,such as Dia-1c,(Dia-2b),Dia-3b were only found in E.dayaoshanensis and Est-2b,Est-3a only in E.prinoides var.daduheensis,while Idh-1d occurred in Lizhipipa,a cultivar of E.japonica.The result also indicated that genetic composition was highly differentiated among different species in genus Eriobotrya.Based on multi-locos genotype fingerprinting cultivars with 53 alleles at 22 loci,111 of 113 loquat cultivars or selections were clear identified,and each cultivar has its unique allozyme genotypy (fringerprint,)suggesting allozyme is a useful marker for loquat cultivars (identification,)although the fruit characteristics variations is independent of the isozyme genetic variations examined in a detailed analysis.