The Genomic Quality of Rye B Chromosomes

DNA preparations from rye plants containing 0 and 6B chromosomes were very similar when assessed by analytical ultraoentrifugation, renaturation kinetics and thermal denaturation. There was a suggestion that B chromosome DNA was slightly richer in sequences of high cytosine and guanine content than that of the A complement. In situ hybridization showed that the DNA of the rye B chromosomes was not all highly repetitious. The DNA of these B chromosomes is therefore concluded to be representative of a broad spectrum of DNA similar to the normal genome from which it was presumably derived.