Résumé
Pervenets is a sunflower mutant with a seed oil oleic acid content greater than 65%. It was obtained after mutagenesis treatment on VNIIMK 8931. Several commercial varieties derived from Pervenets and breeding materials with a high oleic acid content have been marketed. However, the genetics of this trait are still not fully understood by breeders. To characterize the Pervenets mutation, we studied RFLP in relation to high oleic acid content. We performed diversity analyses on 239 genotypes with cDNA sequences coding for Δ9- and Δ12-desaturases as probes. The Δ12 RFLPs enabled us to identify at least two independent loci. One Δ12 RFLP allele (Δ12HOS) was strictly correlated to high oleic acid content, whereas no correlation was found between Δ9-desaturase polymorphism and high oleic acid content. These results enabled to us estimate the genetic distance between the marker and the Pervenets mutation loci. An F2 segregating population of 107 plants confirmed the correlation between high oleic acid content and Δ12HOS, indicating tight genetic linkage. The nature of the Pervenets dominant mutation and the complexity of the high oleic acid content trait are discussed.