Identification of S Haplotypes in Commercial F1 Hybrid Cultivars of Radish by PCR-RFLP Analysis

Abstract

Self incompatibility (SI) of Cruciferous crop has been studied not only to find out the evolution of the self incompat-ibility system, but also to identify the S haplotypes of the plant materials on the practical breeding programs. It has been reportedthat SRK and SCR/SP1 are the main components of the pistil and pollen interaction on the process of SI. In adition, SLG is also1 radish cul-tivars cultivated in Korea, SLG and SRK DNA of the 44 cultivars were analyzed with PCR-RFLP. Totally 12 S haplotypes werefound from the comercial F1 cultivars. S4 (II), S5 (II), S8 (I), S17 (I), and S21 (II) were frequently identified from over 10 cultivars.S11 (I), S13 (II), S18 (I), S30 (I), and S31tified from the cultivars, 79% of cultivars have only 5 different S-alleles. The frequency of the class II S haplotype (41/7) washigher than that of class I (36/77), but the number of class I haplotype was larger than that of class II. Surprisingly, 7 of the 44 F1hybrid cultivars have only one S-allele by this method. We could not decide whether this homozygosity of S-allele is originatedfrom the S-allele itself of the cultivars or limitation of PCR-RFLP analysis. To confirm this homozygosity on the F1 hybrid cul-