title: Genotyping-by-sequencing in an orphan plant species Physocarpus opulifolius helps identify the evolutionary origins of the genus Prunus.
abstract: BACKGROUND
  The Rosaceae family encompasses numerous genera exhibiting morphological diversification in fruit types and plant habit as well as a wide variety of chromosome numbers. Comparative genomics between various Rosaceous genera has led to the hypothesis that the ancestral genome of the family contained nine chromosomes, however, the synteny studies performed in the Rosaceae to date encompass species with base chromosome numbers x = 7 (Fragaria), x = 8 (Prunus), and x = 17 (Malus), and no study has included species from one of the many Rosaceous genera containing a base chromosome number of x = 9.
  
  
  RESULTS
  A genetic linkage map of the species Physocarpus opulifolius (x = 9) was populated with sequence characterised SNP markers using genotyping by sequencing. This allowed for the first time, the extent of the genome diversification of a Rosaceous genus with a base chromosome number of x = 9 to be performed. Orthologous loci distributed throughout the nine chromosomes of Physocarpus and the eight chromosomes of Prunus were identified which permitted a meaningful comparison of the genomes of these two genera to be made.
  
  
  CONCLUSIONS
  The study revealed a high level of macro-synteny between the two genomes, and relatively few chromosomal rearrangements, as has been observed in studies of other Rosaceous genomes, lending further support for a relatively simple model of genomic evolution in Rosaceae.
authors.affiliation: Research and Innovation Centre, Fondazione Edmund Mach, via Mach 1, 38010, San Michele All'adige, TN, Italy. matteo.buti@hotmail.it.
authors.forename: Matteo
authors.initials: M
authors.lastname: Buti
authors.affiliation: Research and Innovation Centre, Fondazione Edmund Mach, via Mach 1, 38010, San Michele All'adige, TN, Italy.|Driscoll's Genetics Ltd., East Malling Enterprise Centre, New Road, East Malling, Kent, ME19 6BJ, UK.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Sargent
authors.affiliation: ARC Infruitec-Nietvoorbij, Private Bag X5026, Stellenbosch, 7599, South Africa.
authors.forename: Khethani G
authors.initials: KG
authors.lastname: Mhelembe
authors.affiliation: Research and Innovation Centre, Fondazione Edmund Mach, via Mach 1, 38010, San Michele All'adige, TN, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Delfino
authors.affiliation: ARC Infruitec-Nietvoorbij, Private Bag X5026, Stellenbosch, 7599, South Africa.
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Tobutt
authors.affiliation: Research and Innovation Centre, Fondazione Edmund Mach, via Mach 1, 38010, San Michele All'adige, TN, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Velasco
mesh_terms: D032461:Chromosomes, Plant; D019143:Evolution, Molecular; D005838:Genotype; D027861:Prunus / Q000235:genetics*; D027824:Rosaceae / Q000235:genetics*
keywords: Comparative mapping; Genome evolution; Genomics; Plant breeding; Solanaceae