| Abstract Detail
Systematics Section Berry, Paul E. [1], Riina, Ricarda [1], Van Ee, Benjamin [2]. A second-generation molecular phylogeny of the giant genus Croton (Euphorbiaceae) with evidence from three genomes. The first two-gene molecular phylogeny of Croton (Euphorbiaceae) published four years ago sampled 78 of the estimated 1250 species in the genus. It allowed us to properly circumscribe the genus and segregate from it the small genus Astraea, as well as to assess the sectional classification of Webster. However, the non-coding nuclear ITS and chloroplast trnL-F markers do not provide supported resolution along the backbone of the phylogeny, and there are a few notable incongruences between them. Evidence from three additional chloroplast markers (rbcL, ndhF, and matK) is consistent with the phylogenetic signal from trnL-F and did not increase support. To address this shortcoming, we have added DNA sequence data from a single- or low-copy coding nuclear marker and a coding mitochondrial marker. We have also greatly increased our sampling of the genus, to over 120 species and 150 accessions. Our second-generation phylogeny has led to much greater support at deeper nodes of the genus and a better circumscription of the sections or subclades within Croton. It also allows us to better understand the incongruences between nuclear and chloroplast markers in certain cases. Log in to add this item to your schedule
1 - University of Michigan, Herbarium & Dept. Ecology and Evolutionary Biology, 3600 Varisty Drive, Ann Arbor, MI, 48108, USA 2 - Harvard University, Arnold Arboretum, Harvard University Herbaria, 22 Divinity Avenue, Cambridge, MA, 02138, USA
Keywords: Croton Euphorbiaceae megadiverse low copy nuclear markers mitochondrial markers molecular phylogenetics gene incongruence.
Presentation Type: Oral Paper:Papers for BSA Sections Session: 57 Location: Maybird/Cliff Lodge - Level C Date: Wednesday, July 29th, 2009 Time: 9:45 AM Number: 57008 Abstract ID:825 |