The Sicilian wild tetraploid oat Avena insularis is a close relative of A.
magna and A. murphyi and is more plausible than either of these two species
as the immediate tetraploid ancestor of A. sterilis and the other hexaploi
d oats. This report presents the C-banding karyotype of A. insularis. As in
A. magna and A. murphyi, the chromosomal complement can be divided into tw
o groups, one predominantly heterochromatic and the other predominantly euc
hromatic. The heterochromatic chromosome group of A. insularis consists of
three pairs of metacentric and four pairs of submetacentric chromosomes. Th
e euchromatic chromosome group consists of one pair of metacentric, five pa
irs of submetacentric, and one pair of subtelocentric chromosomes.