Molecular cytogenetic analysis of wheat–barley hybrids using genomic in situ hybridization and barley microsatellite markers

Abstract

In the present investigation, genomic in situ hybridization (GISH) and barley microsatellite markers were used to analyse the genome constitution of wheat–barley hybrids from two backcross generations (BC1and BC2). Two BC1plants carried 3 and 6 barley chromosomes, respectively, according to GISH data. Additional chromosomal fragments were detected using microsatellites. Five BC2plants possessed complete barley chromosomes or chromosome segments and six BC2plants did not preserve barley genetic material. Molecular markers revealed segments of the barley genome with the size of one marker only, which probably resulted from recombination between wheat and barley chromosomes. The screening of backcrossed populations from intergeneric hybrids could be effectively conducted using both genomic in situ hybridization and molecular microsatellite markers. GISH images presented a general overview of the genome constitution of the hybrid plants, while microsatellite analysis revealed the genetic identity of the alien chromosomes and chromosomal segments introgressed. These methods were complementary and provided comprehensive information about the genomic constitution of the plants produced.Key words: wheat–barley hybrids, introgressive hybridization, recombination, molecular markers, genomic in situ hybridization (GISH).