Isozyme electrophoresis was used to study the origin of Bromus pectinatus (Poaceae, Pooideae). The morphological characteristics of B. pectinatus are intermediate between B. japonicus of sect. Bromus and B. tectorum of sect. Genea. Previous authors have suggested that sects. Bromus and Genea may be linked through B. pectinatus, a species that has been classiﬁed in sect. Bromus, though this placement has been questioned. Isozyme data support the allotetraploid nature of B. pectinatus and its position between sects. Bromus and Genea. Several heterozymes are consistent with the view that B. pectinatus may have arisen through polyploidization of a hybrid between B. japonicus of sect. Bromus and B. tectorum of sect. Genea.
"Preliminary Isozyme Evidence on the Hybrid Origin and Diploid Progenitors of Bromus pectinatus (Poaceae),"
Aliso: A Journal of Systematic and Evolutionary Botany:
1, Article 36.
Available at: http://scholarship.claremont.edu/aliso/vol23/iss1/36