title: Molecular phylogeny revealed distinct origin of the Y and St genome in Elymus longearistatus (Triticeae: Poaceae).
abstract: Cytogenetic data has indicated the presence of St and Y genome in Elymus longearistatus (Boiss.) Tzvelev. However, a random amplified polymorphic DNA (RAPD) based sequence tagged site (STS) study suggested one accession of Pseudoroegneria spicata (Pursh) Á Löve (St genome) as a potential Y genome donor candidate in tetraploid E. longearistatus. To examine the origin of Y genome in and the phylogeny of tetraploid E. longearistatus, sequences of cpDNA (RPS16 and TrnD/T intergenic spacer) and single copy nuclear genes (EF-G and HTL) from eight accessions of E. longearistatus, six StY genomic Elymus species and 62 accessions of diploid in Triticeae were analyzed. The cpDNA data suggested that P. stipifolia (St) is the most likely maternal donor of these six Iranian accessions of E. longearistatus, although P. strigosa could not be excluded. Two nuclear gene data convincingly showed that tetraploid E. longearistatus contains two distinct genomes, St and Y genome. The phylogenetic analyses from both the EF-G and HTL rejected the previous suggestion that accession PI232134 of Pseudoroegneria spicata (Pursh) Á Löve (St genome) was potential Y genome donor to E. longearistatus. Phylogenetic analyses revealed a separation of the Y genome sequences in Iranian accessions of E. longearistatus from the sequences in the Pakistan accession, indicating that geographic isolation might influence the evolution of the Y genome in E. longearistatus.
authors.affiliation: Biology Department, Saint Mary's University, 923 Robie Street, Halifax, Nova Scotia B3H 3C3, Canada.
authors.forename: Qianni
authors.initials: Q
authors.lastname: Hu
authors.affiliation: College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Dongfa
authors.initials: D
authors.lastname: Sun
authors.affiliation: Biology Department, Saint Mary's University, 923 Robie Street, Halifax, Nova Scotia B3H 3C3, Canada. Electronic address: genlou.sun@smu.ca.
authors.forename: Genlou
authors.initials: G
authors.lastname: Sun
mesh_terms: D001499:Bayes Theorem; D002467:Cell Nucleus / Q000235:genetics; D018742:DNA, Chloroplast / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D031749:Elymus / Q000145:classification* / Q000235:genetics; D019143:Evolution, Molecular; D018745:Genome, Plant; D007492:Iran; D016013:Likelihood Functions; D008957:Models, Genetic; D010154:Pakistan; D020653:Peptide Elongation Factor G / Q000235:genetics; D010802:Phylogeny; D006109:Poaceae / Q000145:classification / Q000235:genetics; D019105:Random Amplified Polymorphic DNA Technique; D017422:Sequence Analysis, DNA
chemical_list: D018742:DNA, Chloroplast; D018744:DNA, Plant; D020653:Peptide Elongation Factor G
keywords: Elymus longearistatus; Geographical differentiation; Multiple origins; Polyploidy; Y genome