A Database for Triticeae and Avena
II.44. Blue aleurone caused by complementary genes in very close
G. A. Wiebe, Collaborator, USDA, ARS, PSRD, Cereal Crops Research Branch,
Beltsville, Maryland 20705, U.S.A.
The blue aleurone color in barley shows xenia in the Fl when crossed
with white aleurone types, and normally homozygous blue and white lines
can be selected in the progeny. The type reported here is an exception
in that no homozygous blue line has been established after many attempts.
In this case, the xenia plants have 50% blue kernels and 50% have white
kernels. All blue kernels give only xenia plants and all white kernels
give only white kerneled plants. Every xenia plant repeats this cycle.
Crosses between white kerneled plants in some cases give xenia F1's, indicating
the presence of two different kinds of white plants and a complementary
gene action for blue. Further tests confirm this pattern indicating a very
close translinkage between the genes. No homozygous blue aleurone line
was established from more than 5,000 blue kernels tested. The locus of
these linked genes is unknown. Therefore, x and y will be used in the formulas.
The original xenia plant was selected from Composite Cross 5 CI 6620,
and therefore the parents are unknown. The genotype
of this plant is:
Where Blx + Bly are complementary and give blue, the two white types
breed true, but restore the xenia type when crossed.
BGN 2 toc
BGN Main Index