Mapping and Tagging of Simply Inherited Traits - Genetics, Genomics and Breeding of Crop Plants - page 131

control in sunflower hybrid seed production. Yue et al. (2008a) showed that
the lemon ray flower color was controlled by two recessive genes and mapped
one of the genes yf1 to LG 11 of the public SSR map. Yue et al. (2008b)
identified and mapped a major gene ( yl ) conferring chlorophyll deficiency,
which generated a yellow leaf phenotype. TRAP and SSR markers were
used to map the recessive gene using BSA to LG 10 of the public SSR map.
Furthermore, both traits could be useful to understand the genetic factors,
which control the carotenoid biosynthesis and the process of chlorophyll
metabolism, respectively.
4.6 Seed Quality
4.6.1 Oil Quality
Sunflower seed oil is a naturally rich source of oleic and linoleic acid,
accounting for about 900 g/kg of oil. Linoleic acid contents range from
about 600-800 g/kg and oleic acid contents range from 150-350 g/kg (Miller
and Fick 1997). Soldatov (1976) developed Pervenets, a high oleic acid
sunflower germplasm, by treating seeds with dimethyl sulfate and selecting
among progeny with elevated oleic acid contents. In the last years, the
cultivation of mid oleic or high oleic sunflower cultivars increased year by
year in most countries. The inheritance of the high oleic acid phenotype in
sunflower has been widely studied with crosses between different high
oleic stocks originating from Pervenets and different low oleic sources. The
oleic acid increase in Pervenets was subsequently discovered to be partly
caused by an incompletely dominant mutation ( Ol ). Ol greatly increases
oleic acid concentrations in sunflower seed oils, produces discrete (non-
overlapping) or non-discrete (overlapping) oleic acid classes in different
genetic backgrounds and is necessary but not always sufficient for
producing high oleic acid concentrations (for references see Schuppert et al.
2006). The mutant Ol allele identified through phenotypic analyses seems
to be a duplicated FAD2-1 (oleoyl-phosphatidyl choline desaturase) allele
identified through molecular analyses (Hongtrakul 1998; Lacombe and
Bervillé 2001; Lacombe et al. 2002; Pérez-Vich et al. 2002; Schuppert et al.
2003, 2006). FAD2 is necessary for the synthesis of linoleic from oleic acid
(Mekhedov et al. 2000). FAD2-1 has been mapped to LG 14 (Lacombe and
Bervillé 2001; Pérez-Vich et al. 2002; Schuppert et al. 2003, 2006).
In addition to high oleic sunflower lines, mutant lines with a high stearic
acid content (>25%) in their seed oil have been developed. This high stearic
acid oil is demanded for producing a wide range of margarine and spread
products (Pérez-Vich et al. 2004b). Two high stearic acid lines have been
characterized in more detail: CAS-3 exhibiting a high stearic acid content of
26% (Osorio et al. 1995) and CAS-14 showing a very high stearic acid content