title: Introgression potential between safflower (Carthamus tinctorius) and wild relatives of the genus Carthamus.
abstract: BACKGROUND
  Safflower, Carthamus tinctorius, is a thistle that is grown commercially for the production of oil and birdseed and recently, as a host for the production of transgenic pharmaceutical proteins. C. tinctorius can cross with a number of its wild relatives, creating the possibility of gene flow from safflower to weedy species. In this study we looked at the introgression potential between different members of the genus Carthamus, measured the fitness of the parents versus the F1 hybrids, followed the segregation of a specific transgene in the progeny and tried to identify traits important for adaptation to different environments.
  
  
  RESULTS
  Safflower hybridized and produced viable offspring with members of the section Carthamus and species with chromosome numbers of n = 10 and n = 22, but not with n = 32. The T-DNA construct of a transgenic C. tinctorius line was passed on to the F1 progeny in a Mendelian fashion, except in one specific cross, where it was deleted at a frequency of approximately 21%. Analyzing fitness and key morphological traits like colored seeds, shattering seed heads and the presence of a pappus, we found no evidence of hybrid vigour or increased weediness in the F1 hybrids of commercial safflower and its wild relatives.
  
  
  CONCLUSIONS
  Our results suggest that hybridization between commercial safflower and its wild relatives, while feasible in most cases we studied, does not generate progeny with higher propensity for weediness.
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada.
authors.forename: Marion
authors.initials: M
authors.lastname: Mayerhofer
authors.forename: Reinhold
authors.initials: R
authors.lastname: Mayerhofer
authors.forename: Deborah
authors.initials: D
authors.lastname: Topinka
authors.forename: Jed
authors.initials: J
authors.lastname: Christianson
authors.forename: Allen G
authors.initials: AG
authors.lastname: Good
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D031187:Carthamus tinctorius / Q000145:classification / Q000235:genetics*; D018556:Crops, Agricultural / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D019143:Evolution, Molecular; D051456:Gene Flow; D056084:Genetic Fitness; D005838:Genotype; D006824:Hybridization, Genetic; D030821:Plants, Genetically Modified / Q000235:genetics
chemical_list: D018744:DNA, Plant