title: Structural variation in the heterochromatin of rye chromosomes in triticales.
abstract: Although Giemsa C-banding techniques have been used extensively for assaying cereal heterochromatin, a more specific technique for analyzing cereal heterochromatin has been developed recently with the isolation of DNA sequences present in heterochromatin and their employment in in situ hybridization to cereal chromosomes. A number of triticales were examined for the occurrence of modified rye chromosomes using the in situ hybridization technique. With a heterogeneous sequence probe the amount of rye heterochromatin appears to be relatively constant in wheat backgrounds but when a specific sequence probe was employed variation was observed. Whether this variation reflects polymorphism in rye or whether it is a result of adaption of the rye genome to coexistence with the wheat genome in triticales is discussed. - The triticale Rosner was examined in detail and it was established that the rye chromosome 2R had been replaced by the wheat chromosome 2D.
authors.affiliation: Division of Plant Industry, CSIRO, Canberra, Australia.
authors.forename: R
authors.initials: R
authors.lastname: Appels
authors.forename: J P
authors.initials: JP
authors.lastname: Gustafson
authors.forename: C E
authors.initials: CE
authors.lastname: May