title: Polyphyly, gene-duplication and extensive allopolyploidy framed the evolution of the ephemeral Vulpia grasses and other fine-leaved Loliinae (Poaceae).
abstract: The fine-leaved Loliinae is one of the temperate grass lineages that is richest in number of evolutionary switches from perennial to annual life-cycle, and also shows one of the most complex reticulate patterns involving distinct diploid and allopolyploid lineages. Eight distinct annual lineages, that have traditionally been placed in the genus Vulpia and in other fine-leaved ephemeral genera, have apparently emerged from different perennial Festuca ancestors. The phenotypically similar Vulpia taxa have been reconstructed as polyphyletic, with polyploid lineages showing unclear relationships to their purported diploid relatives. Interspecific and intergeneric hybridization is, however, rampant across different lineages. An evolutionary analysis based on cloned nuclear low-copy GBSSI (Granule-Bound Starch Synthase I) and multicopy ITS (Internal Transcribed Spacer) sequences has been conducted on representatives of most Vulpia species and other fine-leaved lineages, using Bayesian consensus and agreement trees, networking split graphs and species tree-based approaches, to disentangle their phylogenetic relationships and to identify the parental genome donors of the allopolyploids. Both data sets were able to reconstruct a congruent phylogeny in which Vulpia was resolved as polyphyletic from at least three main ancestral diploid lineages. These, in turn, participated in the origin of the derived allopolyploid Vulpia lineages together with other Festuca-like, Psilurus-like and some unknown genome donors. Long-distance dispersal events were inferred to explain the polytopic origin of the Mediterranean and American Vulpia lineages.
authors: Departamento de Ciencias Agrarias y del Medio Natural (Botánica), Escuela Politécnica Superior-Huesca, Universidad de Zaragoza, Ctra. Cuarte km 1, 22071 Huesca, Spain.
authors: A J
authors: AJ
authors: Díaz-Pérez
authors: Departamento de Ciencias Agrarias y del Medio Natural (Botánica), Escuela Politécnica Superior-Huesca, Universidad de Zaragoza, Ctra. Cuarte km 1, 22071 Huesca, Spain.
authors: M
authors: M
authors: Sharifi-Tehrani
authors: Departamento de Ciencias Agrarias y del Medio Natural (Botánica), Escuela Politécnica Superior-Huesca, Universidad de Zaragoza, Ctra. Cuarte km 1, 22071 Huesca, Spain.
authors: L A
authors: LA
authors: Inda
authors: Departamento de Ciencias Agrarias y del Medio Natural (Botánica), Escuela Politécnica Superior-Huesca, Universidad de Zaragoza, Ctra. Cuarte km 1, 22071 Huesca, Spain; Department of Botany, Institute of Biology, Tomsk State University, Lenin Av. 36, Tomsk 634050, Russia. Electronic address: pcatalan@unizar.es.
authors: P
authors: P
authors: Catalán
mesh_terms: D001499:Bayes Theorem; D018744:DNA, Plant / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D019143:Evolution, Molecular; D020440:Gene Duplication; D010802:Phylogeny; D006109:Poaceae / Q000145:classification* / Q000235:genetics; D011123:Polyploidy; D017422:Sequence Analysis, DNA; D013214:Starch Synthase / Q000235:genetics
chemical_list: D018744:DNA, Plant; D021903:DNA, Ribosomal Spacer; C434607:granule-bound starch synthase I; D013214:Starch Synthase
keywords: Fine-leaved Loliinae; Interspecific hybridization; Mediterranean and American silver grasses; Nuclear (ITS, GBSSI) genes; Polyploid speciation; Species tree reconstruction