Development, polymorphism, and cross-taxon utility of EST-SSR markers from safflower (Carthamus tinctorius L.)

• Main Authors: Chapman, Mark A. (Author), Hvala, John (Author), Strever, Jason (Author), Matvienko, Marta (Author), Kozik, Alexander (Author), Michelmore, Richard W. (Author), Tang, Shunxue (Author), Knapp, Steven J. (Author), Burke, John M. (Author)
• Format: Article
• Language: English
• Published: 2009-12-01.
• Subjects: Article
• Online Access: Get fulltext; Get fulltext

 Due to their highly polymorphic and codominant nature, simple-sequence repeat (SSR) markers are a common choice for assaying genetic diversity and genetic mapping. In this paper, we describe the generation of an expressed-sequence tag (EST) collection for the oilseed crop safflower and the subsequent development of EST-SSR markers for the genetic analysis of safflower and related species. We assembled 40,874 reads into 19,395 unigenes, of which 4,416 (22.8%) contained at least one SSR. Primer pairs were developed and tested for 384 of these loci, resulting in a collection of 104 polymorphic markers that amplify reliably across 27 accessions (3 species) of the genus Carthamus. These markers exhibited a high level of polymorphism, with an average of 6.0 ± 0.4 alleles per locus and an average gene diversity of 0.54 ± 0.03 across Carthamus species. In terms of cross-taxon transferability, 50% of these primer pairs produced an amplicon in at least one other species in the Asteraceae, and 28% produced an amplicon in at least one species outside the safflower subfamily (i.e., lettuce, sunflower, and/or Gerbera). These markers represent a valuable resource for the genetic analysis of safflower and related species, and also have the potential to facilitate comparative map-based analyses across a broader array of taxa within the Asteraceae.