title: Hedysarum L. (Fabaceae: Hedysareae) Is Not Monophyletic - Evidence from Phylogenetic Analyses Based on Five Nuclear and Five Plastid Sequences.
abstract: The legume family (Fabaceae) exhibits a high level of species diversity and evolutionary success worldwide. Previous phylogenetic studies of the genus Hedysarum L. (Fabaceae: Hedysareae) showed that the nuclear and the plastid topologies might be incongruent, and the systematic position of the Hedysarum sect. Stracheya clade was uncertain. In this study, phylogenetic relationships of Hedysarum were investigated based on the nuclear ITS, ETS, PGDH, SQD1, TRPT and the plastid psbA-trnH, trnC-petN, trnL-trnF, trnS-trnG, petN-psbM sequences. Both nuclear and plastid data support two major lineages in Hedysarum: the Hedysarum s.s. clade and the Sartoria clade. In the nuclear tree, Hedysarum is biphyletic with the Hedysarum s.s. clade sister to the Corethrodendron + Eversmannia + Greuteria + Onobrychis clade (the CEGO clade), whereas the Sartoria clade is sister to the genus Taverniera DC. In the plastid tree, Hedysarum is monophyletic and sister to Taverniera. The incongruent position of the Hedysarum s.s. clade between the nuclear and plastid trees may be best explained by a chloroplast capture hypothesis via introgression. The Hedysarum sect. Stracheya clade is resolved as sister to the H. sect. Hedysarum clade in both nuclear and plastid trees, and our analyses support merging Stracheya into Hedysarum. Based on our new evidence from multiple sequences, Hedysarum is not monophyletic, and its generic delimitation needs to be reconsidered.
authors.affiliation: College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Pei-Liang
authors.initials: PL
authors.lastname: Liu
authors.affiliation: Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington D.C., United States of America.
authors.forename: Jun
authors.initials: J
authors.lastname: Wen
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Duan
authors.affiliation: Department of Biology, Faculty of Science, Selçuk University, Konya, Turkey.
authors.forename: Emine
authors.initials: E
authors.lastname: Arslan
authors.affiliation: Department of Biology, Faculty of Science, Selçuk University, Konya, Turkey.
authors.forename: Kuddisi
authors.initials: K
authors.lastname: Ertuğrul
authors.affiliation: College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Zhao-Yang
authors.initials: ZY
authors.lastname: Chang
mesh_terms: D002467:Cell Nucleus / Q000235:genetics; D018742:DNA, Chloroplast; D018744:DNA, Plant; D019143:Evolution, Molecular; D007887:Fabaceae / Q000235:genetics*; D010802:Phylogeny; D018087:Plastids
chemical_list: D018742:DNA, Chloroplast; D018744:DNA, Plant