Polyploidization has played an important role in the evolution of vertebrates, particularly at the base of Teleostei-an enormously successful ray-finned fish group with additional genome doublings on lower taxonomic levels. The investigation of post-polyploid genome dynamics might provide important clues about the evolution and ecology of respective species and can help to decipher the role of ...

The effect of the gene dosage on the expression of rRNAs was studied in Hypericum perforatum. The methylation levels of rDNA were analysed using the isoschizomers MspI and HpaII and eleven additional methylation-sensitive enzymes. No differences in rDNA methylation were observed between diploids and tetraploids at an early ontogenetic stage.

Abstract The grass Deschampsia cespitosa is a variable taxon out of which many varieties, subspecies and endemic species have been separated. In this paper, the variation in genome size (GS) ploidy including several its two related Eurasia was investigated by flow cytometric (FCM) measurements. GS data were also to specific environments reproduction mode. Ploidy levels found FCM confirmed chrom...

BACKGROUND AND AIMS Polyploidization, the doubling of chromosome sets, is common in angiosperms and has a range of evolutionary consequences. Newly formed polyploid lineages are reproductively isolated from their diploid progenitors due to triploid sterility, but also prone to extinction because compatible mating partners are rare. Models have suggested that assortative mating and increased rep...

With respect to the maternally inherited large subunit of fraction I protein, Chen et al. (1) found that Triticum boeoticum and T. urartu had identical polypeptide patterns, and Aegilops speltoides had a different one identical with that of the tetraploid wheats. From this evidence they inferred that Ae. speltoides. but neither T. boeoticum nor T. urartu, could have been the maternal parent of ...

HE selfand cross-incompatibilities of a number of obligately cross-polliT nated species of flowering plants are genetically determined by series of multiple oppositional alleles. The oppositional or personate incompatibility system was first described, with substantiating data, by EAST and MANGELSDORF (1925) for Nicotiana species. The existence of oppositional alleles has been subsequently demo...