[Abstract]

Hybrid cultivars of Korean peppers (Capsicum annuum L.) have been developed using the cytoplasmic-genic male sterility (CGMS) or genic male sterility (GMS) system for economical seed production. More than 20 GMS genes have been reported in pepper, and the naturally occurring msk has been widely used for pepper breeding in Korea. In this study, we aimed to construct a fine map near the msk locus by developing high-resolution melting (HRM) markers and identified candidate genes for the msk gene. A total of 806 F2 plants was used for marker development and fine map construction. A fine map was constructed using 14 HRM markers developed from SNPs identified through next-generation resequencing of male-fertile (MskMsk) and male-sterile (mskmsk) plants. The genetic linkage map was compared to the physical map of reference pepper chromosome 10, and marker order of the map was syntenic. The five HRM markers HRM1524718, HRM1530835, HRM1531314, HRM1534857, and HRM1535009 co-segregated with phenotypes of male-fertility. The result delimited to a region of 142 kb (693 to 835 kb) on chromosome 10, and 12 candidate genes were identified with the region. A strong candidate gene, T459_24638 (CaMYB80), encodes transcription factor MYB80, which was reported to be required for pollen development and regulation of tapetal programmed cell death in Arabidopsis thaliana. Sequence comparison of the T459_24638 gene between the male-fertile (MskMsk) and -sterile (mskmsk) plants revealed a 163-bp insertion in the third exon of the msk allele, resulting in a premature stop codon, implying that disruption of this gene might cause male sterility. Based on the insertion, msk-HRM markers were developed to distinguish between Msk and msk alleles. These results suggest that the gene-based marker may accelerate hybrid pepper breeding using GMS. Our identification of the candidate gene contributes to the understanding of the molecular mechanism of pollen development in pepper.

[Article Information]

 - Source title:  Horticulture, Environment, and Biotechnology, 66, 879-888

- DOI: 10.1007/s13580-025-00693-z

[Author PURE profile]

 Professor Jundae Lee

- Department of Horticulture

- ORCID: https://orcid.org/0000-0002-2029-5702