Genetic determinism of δ3-carene in maritime pine using RAPD markers.

An F2 progeny of maritime pine (Pinus pinaster Aïton) was used to investigate the mode of inheritance of δ3-carene using a quantitative and a qualitative approach. A previously reported genetic map constructed with random amplified polymorphic DNA (RAPD) markers made it possible to locate one major quantitative trait locus (QTL) accounting for most of the phenotypic variation of this trait on linkage group 5. In the qualitative approach, the "C" locus that controls the relative quantity of δ3-carene (C+ for the richness allele and C− for the poorness allele) was found to be strongly associated with RAPD markers in the same genomic region of linkage group 5. The colocation between the QTL and the "C" locus suggests that a major gene or closely linked loci affect the variation in δ3-carene expression. Key words : Pinus pinaster, terpenes, QTL, RAPD, linkage analysis.