Towards premium rapeseed oil: leveraging allelic variation in BnaFAD2.A5, BnaFAD3.A4 and BnaFAD3.C4 for molecular design breeding

BACKGROUND: Improving the quality and frying stability of rapeseed oil has long been an important goal in rapeseed quality breeding. This goal can be achieved through molecular marker-assisted selection (MAS) combined with speed breeding strategies. In this study, genomic data from the high-oleic-acid, low-linolenic-acid material L3 and the recessive genic male sterile (RGMS) line RG430A were used to identify functional variation sites underlying key quality traits: one governing oleic acid content and two controlling linolenic acid content. Additionally, Kompetitive Allele-Specific PCR markers were developed to efficiently genotype these oleic and linolenic acid-related variants. RESULTS: By integrating speed breeding with MAS and phenotypic screening, a new RGMS line was developed with high oleic acid, low linolenic acid content, and favorable agronomic performance. Compared with the original RG430A, the new line shows an approximately 15.0% increase in oleic acid content (reaching 78.0%) and an approximately 52.6% reduction in linolenic acid content (decreasing to 3.6%), with no significant alterations in major agronomic traits. CONCLUSIONS: Our study offers strategic insights for rapeseed quality breeding, and the developed RGMS line represents a promising germplasm resource for future high-quality hybrid breeding.