Sunflower (Helianthus annuus L.) seed color is determined by pigmentat
ion of three layers of the pericarp (hull): epidermis, hypodermis, and
phytomelanin layer. A gene with major effects on hypodermis color was
reported previously. How ever, genetic factors that determine the pre
sence or absence of pigment in the hypodermis have not been reported.
We identified RFLP markers linked to factor(s) affecting hypodermis pi
gmentation and assessed the relationship between this trait and oil pe
rcentage in sunflower seed. An F-2 single-cross population was produce
d from homozygous and homogeneous inbred parents ZENB8 and HA89, with
pigmented and unpigmented hypodermis, respectively. Two hundred sixty-
seven F-2 plants and their F-3 families were evaluated. A dominant fac
tor (Hyp) determining the presence of white pigments in the hypodermis
was located to Linkage group 'G'. Seeds with white hypodermis had low
er oil percentage than those with unpigmented hypodermis. The Hyp fact
or was Located in the same map interval as one QTL with major effects
on seed oil percentage in this population. Knowledge of genetic linkag
e among DNA markers, hypodermis pigmentation, and oil percentage shoul
d enhance breeding programs.