Comparative analysis of genomes of six species of Hedysarum L. (Fabaceae) by the rapidGISH technique

A comparative analysis of genomes of six Hedysarum species was carried out using the rapid genomic in situ hybridization (rapidGISH) technique, which makes it possible to identify common highly repetitive DNA sequences, and also shows the patterns of their distribution on chromosomes of the studied species. Dispersed localization of genomic DNA of H. flavescens (sect. Hedysarum) was found on chromosomes of H. alpinum and H. theinum (both belonged to sect. Hedysarum). On chromosomes of H. neglectum from the section Hedysarum, clustered hybridization signals of genomic DNA of H. flavescens were observed. The localization of H. alpinum genomic DNA was found along the all chromosomes of H. flavescens and H. theinum. On chromosomes of H. grandiflorum and H. dahuricum (both from sect. Multicaulia), small clustered and dispersed hybridization signals of genomic DNA of H. flavescens and H. alpinum were found. Thus, in the studied species, common highly repetitive DNA sequences of different types of their chromosome organization were revealed. Our findings indicate the presence of common origin of the species from the sections Hedysarum and Multicaulia with different degree of their relationship.