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Abstract: The StH genome species in Triticeae exhibit different morphological variations and extensive geographic distribution. To estimate the phylogenetic relationship of the StH genome species in Triticeae, mitochondria COXII intron and chloroplast trnL-F sequences of 16 StH genome species were analyzed with those of four Pseudoroegneria species (St) and four Hordeum species (H). Sequence diversity and genealogical analysis suggested that (1) the trnL-F and COXII sequence may evolve faster in the polyploid species than in the diploids; (2) the COXII intron has a high evolutionary rate compared to trnL-F sequence and would provide potentially useful phylogenetic analysis in the StH genome species; (3) different Pseudoroegneria species might serve as the maternal donor during the polyploid speciation of the StH genome species; (4) phylogenetic relationships of the StH genome species may be not linked with the inter-continental disjunction between Eurasian and North American. [Copyright &y& Elsevier]

Mitochondrial CoxII and ITS sequences of 29 tetraploid species with St genome were compared with their related genera and species of Pseudoroegneria (Nevski) Á. Löve (St), Hordeum L. (H), Thinopyrum bessarabicum (Savul. & Rayss) Á. Löve (Eb), Lophopyrum elongatum (Host) Á. Löve (Ee), Agropyron Gaertner (P), Australopyrum (Tzvelev) Löve (W) and Psathyrostachys Nevski (Ns). The results indicate that: (1) the maternal donors of North American and Eurasian StStHH tetraploid species may have acquired their St genome from distinct Pseudoroegneria gene pools, with Pse. spicata (Pursh) Á. Löve potentially the maternal donor of North American species; (2) Lophopyrum is the maternal donor of StStEeEe tetraploid species, hence, Pse. geniculata ssp. scythica (Nevski) Á. Löve, Elytrigia caespitosa (K. Koch) Nevski and El. caespitosa ssp. nodosa (Nevski) Tzvelev should be identified as species of Trichopyrum Á. Löve; (3) tetraploid species with the same maternal donors were more closely related to each other than those with different maternal donors. [ABSTRACT FROM AUTHOR]

Abstract: To evaluate phylogeny of tetraploid with St genome, phylogenetic analyses of RNA polymerase II (RPB2), a member of the nuclear gene family encoding the second largest subunit, were performed. Our results showed that: (1) Roegneria magnicaespes and Roegneria alashanica are related to Pseudoroegneria. (2) Roegneria elytrigioides has StStStSt genomes and should therefore be classified as Pseudoroegneria elytrigioides. (3) Pseudoroegneria tauri and Pseudoroegneria deweyi which have StStPP genomes should be transferred to Douglasdeweya and be renamed as Douglasdeweya wangii and Douglasdeweya deweyi, respectively. (4) Pseudoroegneria geniculata ssp. scythica is related to Pseudoroegneria and Lophyrum, and hence should be identified as a species of Trichopyrum. (5) Pseudoroegneria libanotica might be a parental donor for Elytrigia caespitosa rather than Elytrigia caespitosa ssp. nodosa. It is unreasonable to recognize El. caespitosa ssp. nodosa as a subspecies of El. caespitosa. (6) Interspecific and intergeneric variations are detected in St genome of these tetraploid species. [Copyright &y& Elsevier]

Abstract: To evaluate the phylogenetic relationships of questionable tetraploid species Roegneria alashanica Keng, Roegneria magnicaespes (D.F. Cui) L.B. Cai, Roegneria elytrigioides C. Yen et J.L. Yang, Roegneria grandis Keng and Pseudoroegneria geniculata (Trin.) Á. Löve, the single copy sequences of the plastid acetyl-CoA carboxylase gene (Acc1) were analyzed among the five species and the related diploid and tetraploid species. The results indicated that: (a) R. alashanica contained one set of modified St genome which was closely related to the Ee genome, and the other set of genome was closely related to the P genome; (b) R. magnicaespes contained one set of St genome, the other set of genome might be closely related to the P genome. There are close affinities between R. magnicaespes and R. alashanica; (c) R. elytrigioides contained two sets of St genomes, and it is reasonable to be treated as Pseudoreogneria elytrigioides (C. Yen et J.L. Yang) B.R. Lu; (d) the genome of R. grandis should be designed as StgY. The Stg genome was a differentiated form of the St genome in Pseudoroegneria and was homoeologous with the Y genome in Roegneria; (e) the genomic constitution of P. geniculata was similar to that of R. magnicaespes and R. alashanica and distinctly related to P. geniculata ssp. scythica (EeSt). They should be treated as different species in different genera; and (f) the Y genome was possibly originated from the St genome, and was sister to the St, Ee , Eb and W genomes. [Copyright &y& Elsevier]