Open AccessThe S outh A merican radiation of L epechinia ( L amiaceae): phylogenetics, divergence times and evolution of dioecy
Author(s) -
Drew Bryan T.,
Sytsma Kenneth J.
Publication year - 2013
Publication title -
botanical journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.872
H-Index - 68
eISSN - 1095-8339
pISSN - 0024-4074
DOI - 10.1111/j.1095-8339.2012.01325.x
Subject(s) - biology , internal transcribed spacer , cladogenesis , evolutionary biology , dioecy , lamiaceae , genus , phylogenetic tree , botany , genetics , gene , clade , pollen
L epechinia ( L amiaceae) is a diverse and widespread genus that is important in indigenous N ew W orld culture. We present a phylogenetic analysis of 72 accessions representing 31 species of L epechinia using data from three plastid ( trnL ‐ F , ycf1 , ycf1‐rps15 spacer) and four nuclear [internal transcribed spacer ( ITS) , external transcribed spacer ( ETS) , granule‐bound starch synthase I ( GBSS)I , pentatricopeptide repeat region ( PPR ) ‐ AT3G09060 ] DNA regions. Data were analysed using parsimony, maximum likelihood and B ayesian approaches. Divergence time estimation using BEAST shows L epechinia had a mid/late M iocene origin, perhaps as a response to global cooling patterns. Cladogenesis in most S outh A merican L epechinia is shown to have occurred within the past 5 Myr, presumably as a response to climatic and orogenic events. Dioecy has arisen multiple times in L epechinia , once in N orth A merica and at least twice in S outh A merica, and not necessarily involving gynodioecy as an intermediary step. Dioecy and gynodioecy are demonstrated to be associated with several floral characters, including flower size, number and colour. © 2012 The Linnean Society of London