The Genomic Quality of Rye B Chromosomes

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