Comparison of aspartate aminotransferase isozymes between three wild evergreen azaleas and Kurume azalea

The variation on aspartate aminotransferase (AAT) isozymes of flower buds of Rhododendron kiusianum, R. kiusianum var. sataense, and R. kaempferi, which are considered to be the parental species of Kurume azalea (R. obtusum), and Kurume azalea cultivars was studied by polyacrylamide gel electrophoresis. AAT isozymes of Kurume azalea were compared with those of three wild evergreen azaleas to seek information on the origin of the domestic cultivars. Three loci (Aat-1, Aat-2, and Aat-3) were identified for AAT. The Aat-2 locus in the three wild evergreen azaleas had two common presumptive alleles (Aat-2(100) and Aat-2(80)), and two species-specific presumptive alleles; Aat-2(86) for R. kiusianum var. sataense and Aat-2(90) for R, kaempferi. Aat-3 locus shared the common presumptive alleles (Aat-3(67), Aat-3(58), and Aat-3(49)) with three species. Aat-2 locus of Kurume azalea contained four alleles detected in the above three species and also Aat-2(112) and Aat-2(104) alleles which were not found in R. kiusianum, R. kiusianum var. sataense, and R. kaempferi. These results indicate that Kurume azalea contains genes from R, kiusianum var. sataense and R. kaempferi, and some other related species than the above three wild ones.