Author
Submitted to: Genome
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/12/2017 Publication Date: 2/24/2017 Citation: Wang, R., Larson, S.R., Jensen, K.B. 2017. Differential transferability of EST-SSR primers developed from diploid species Pseudoroegneria spicata, Thinopyrum bessarabicum, and Th. elongatum. Genome. 60(6):530-536. Interpretive Summary: Simple sequence repeat marker technology based on expressed sequence tag (EST-SSR) is a useful genomic tool for genome mapping, characterizing plant species relationships, elucidating genome evolution, and tracing genes on alien chromosome segments. This technology is less utilized in perennial forage Triticeae species. Therefore, we developed EST-SSR primers from three perennial diploid species of the tribe Triticeae and tested on these three species to assess the transferability of primers in the nine (3 source species x 3 target species) primer source-target combinations. Data indicate that the Jb and Je genomes of Thinopyrum bessarabicum and Th. elongatum are more closely related to each other than either one is to the St genome of Pseudoroegneria spicata. The species-specific polymorphic markers identified will be used to fill the gaps in a molecular map of diploid bluebunch wheatgrass (P. spicata) that reveals the location of a QTL for drought/heat tolerance. These markers will also be useful to wheat breeders who want to transfer and trace alien genes from those three genomes for wheat improvement. The knowledge and tools from this study may lead to the development of drought/heat tolerant forage and cereal crops. Technical Abstract: Simple sequence repeat technology based on expressed sequence tag (EST-SSR) is a useful genomic tool for genome mapping, characterizing plant species relationships, elucidating genome evolution, and tracing genes on alien chromosome segments. EST-SSR primers developed from three perennial diploid Triticeae species, Pseudoroegneria spicata (Pursh) A. Love (St genome), Thinopyrum bessarabicum (Savul. & Rayss) A. Love (Jb), and Th. elongatum (Host) D.R. Dewey (Je) were used to produce amplicons in these three species to: (1) assess relative transferability; (2) identify polymorphic species-specific markers; and (3) determine genome relationships among the three species. Due to close relationship between Jb and Je genomes, EST-SSR primers derived from Th. bessarabicum and Th. elongatum had greater transferability to each other than those derived from the St-genome P. spicata. A large number of polymorphic species- and genome-specific EST-SSR amplicons were identified which will be used for construction of genetic maps of these diploid species, and tracing economically useful genes in breeding or gene transfer programs in various Triticeae species. |