Discrimination of repetitive sequences polymorphism in Secale cereale by genomic in situ hybridization-banding

Genomic in situ hybridization banding (GISH-banding), a technique slightly modified from conventional GISH, was used to probe the Chinese native rye (Secale cereale L.) DNA, and enabled us to visualize the individual rye chromosomes and create a universal reference karyotype of the S. cereale chromosome 1R to 7R. The GISH-banding approach used in the present study was able to discriminate S. cereale chromosomes or segments in the wheat (Triticum aestivum L.) background, including the Triticale, wheat-rye addition and translocation lines. Moreover, the GISH-banding pattern of S. cereale subsp. Afghanicum chromosomes was consistent with that of Chinese native rye cv. Jingzhou rye; whereas the GISH-banding pattern of Secale vavilovii was different from that of S. cereale, indicating that GISH-banding can be used to study evolutionary polymorphism in species or subspecies of Secale. In addition, the production and application of GISH-banding to the study of adenine-thymine-riched heterochromatin is discussed.