Abstract:Self-incompatibility in Cruciferous crop such as ornamental kale (Brassica oleracea var. acephala), is a critical reproductive barrier governed primarily by the multiple alleles at the S loci. Ornamental kale is a typical self-incompatibility member of this family. In this study, we constructed the fingerprint map of 20 inbred lines of ornamental kale using 20 pairs of SSR primers, identified a total of 65 allelic variations, averaging 3.25 variations per primer pair. The unweighted pair group method with arithmetic mean (UPGMA) clustered these into three district genetic groups: OK1, OK2, and OK3. Group OK1 is characterized by wrinkled, wavy leaves, with red and purple as the dominant colors. In contrast, group OK2 features smooth leaves that are either wavy or lobed, with white outer leaves. Group OK3 also presents smooth leaves, which may be wavy or lobed, with red and purple as the primary colors. Through the analysis of specific primers in the kinase region of SRK gene, nine SRK haplotypes were identified in these inbred lines including eight class I SRK haplotypes (SRK7, SRK13, SRK14, SRK16, SRK23, SRK36, SRK45, and SRK51) and one class II SRK haplotype (SRK15). The SRK15 haplotype was predominant in the group OK1 (50%), followed by the SRK23 haplotype (20%). In group OK2, the SRK15 and SRK16 haplotype were both major (at 40% each). In group OK3, the SRK23 was predominant (40%). Further analysis of self-incompatible indices confirmed compatibility among inbred lines from the same or different genetic groups, emphasizing the importance of considering both genetic groups and SRK haplotypes in hybrid development.