Ribosomal DNA variation and its phylogenetic implication in the genusBrachypodium (Poaceae)

  title={Ribosomal DNA variation and its phylogenetic implication in the genusBrachypodium (Poaceae)},
  author={Ying Shi and John Draper and Clive A. Stace},
  journal={Plant Systematics and Evolution},
The structure of ribosomal DNA ofBrachypodium and several other grass species was investigated using a heterologous rDNA probe from wheat. Several different rDNA families were present among perennial and annual species within the genus. In contrast to the annual species the perennial species exhibited a very low degree of repeat length variation. An extra Eco RI site and a Hin dIII site were observed in the IGS, which distinguishedBrachypodium from other grass genera. The restriction fragment… 
Compact genomes and complex evolution in the genus Brachypodium
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Comparative cytogenetic analysis of the genomes of the model grass Brachypodium distachyon and its close relatives.
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Evolution and taxonomic split of the model grass Brachypodium distachyon.
The substantial phenotypic, cytogenetic and molecular differences detected among the three B. distachyon sensu lato cytotypes are indicative of major speciation processes within this complex that allow their taxonomic separation into three distinct species.
Phylogeny and Evolution of the Genus Brachypodium
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Laying the Cytotaxonomic Foundations of a New Model Grass, Brachypodium distachyon (L.) Beauv.
In situ hybridization using genomic DNA probes and rDNA markers uncovers a hybrid origin of several of the polyploid ecotypes, and sheds light upon the complex evolution of this species and its close relatives.
EST sequencing and phylogenetic analysis of the model grass Brachypodium distachyon
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The variation in the intergenic spacer of ribosomal DNA (rDNA) of tetraploid wild emmer wheat, Triticum dicoccoides, in Israel was examined in 112 individual plants representing 12 populations tested
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The restriction site variability seen between these three genera demonstrated that sorghum and sugarcane are more closely related to each other than either is to maize, and spacer size variation was found to provide a highly sensitive assay for the genetic contribution of different S. bicolor races and other Sorghum species to a Sorghums population.
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Analysis of inheritance indicates that copy number change is rapid, occurring even among somatic cells of individual plants, and that up to 90% or more of the gene copies are superfluous.
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Cloning and characterization of ribosomal RNA genes from wheat and barley.
Comparison of Hae III and Hpa II digestion of cereal rDNAs and the cloned repeats suggests that most methylated cytosines in natural rDNA are in -CpG-.
The organization and genetics of rDNA length variants in peas
Length variation of pea rDNA is organized between long tandem arrays of rDNA repeat, and the rDNA length classes show simple Mendelian inheritance.