1st International and 10th National Iranian Conference on Bioinformatics

Home Accepted Papers

New insights into the evolutionary history of Bromus pumilio and Bromus gracillimus based on nuclear and plastome molecular data

Paper ID : 1085-ICB10

Authors:

Akram Nasiri *

PhD. candidate, Tarbiat Modares University

Abstract:

Bromus L., classified in its own tribe Bromeae, is a large and complicated grass genus containing about 165 annual to perennial species that is widely distributed in temperate regions of the world. To reassess the phylogenetic relationships among B. pumilio and B. gracillimus, species whose respectively classification within Bromus sects. Boissiera and Nevskiella, and other sections of the Bromus genus, the phylogenetic analyses of 46 Bromus accessions and 4 outgroup specimens were conducted based on DNA sequences from four molecular markers (nrDNA ITS and ETS and plastid rpl32-trnLUAG and matK) in this study. Sequences were assembled, trimmed, and visually assessed using Geneious 11.1.5 software and edited sequences for each gene were aligned separately using the MAFFT v7.388 alignment algorithm. Then, sequences were concatenated as two combined nuclear and plastid DNA dataset matrices using SequenceMatrix. Phylogenetic relationships of Bromus sections were eventually reconstructed by using maximum parsimony, Maximum Likelihood, and Bayesian analyses. In the phylogenetic trees derived from both nrDNA and plastid sequences, Bromus s.l. is monophyletic with strong support and B. pumilio and B. gracillimus are maximally supported as sister taxa. The relationship of the B. pumilio–B. gracillimus lineage to other Bromus lineages differs between the plastid and nrDNA trees. In the nrDNA trees, B. densus and B. pumilio–B. gracillimus are sister groups, whereas in the plastid trees B. pumilio–B. gracillimus and B. sect. Ceratochloa form a strongly supported clade, and this clade and B. densus are successive sister groups to the rest of the genus.

Keywords:

Bromus sect. Boissiera; Bromus sect. Nevskiella; grasses; molecular phylogenetics; evolutionary reconstruction

Status : Paper Accepted (Poster Presentation)