Edinburgh Journal of Botany



TRIBES AND CLADES WITHIN APIACEAE SUBFAMILY APIOIDEAE: THE CONTRIBUTION OF MOLECULAR DATA


S. R. DOWNIE a1, G. M. PLUNKETT a2, M. F. WATSON a3, K. SPALIK a4, D. S. KATZ[hyphen]DOWNIE a1, C. M. VALIEJO[hyphen]ROMAN a5, E. I. TERENTIEVA a6, A. V. TROITSKY a5, B.[hyphen]Y. LEE a1, J. LAHHAM a7 and A. EL[hyphen]OQLAH a7
a1 Department of Plant Biology, University of Illinois, Urbana, IL 61801, USA
a2 Department of Biology, Virginia Commonwealth University, PO Box 842012, Richmond, VA 23284, USA
a3 Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh EH3 9NL
a4 Department of Plant Systematics and Geography, Warsaw University, Aleje Ujazdowskie 4, 00[hyphen]478 Warsaw, Poland
a5 A. N. Belozersky Institute of Physico[hyphen]Chemical Biology, Moscow State University, Moscow 119899, Russia
a6 Botanical Garden, Moscow State University, Moscow 119899, Russia
a7 Department of Biological Sciences, Yarmouk University, Irbid, Jordan

Phylogenetic analyses of chloroplast gene (rbcL, matK), intron (rpl16, rps16, rpoC1) and nuclear ribosomal DNA internal transcribed spacer (ITS) sequences and chloroplast DNA restriction sites, with supplementary data from variation in size of the chloroplast genome inverted repeat, have been used to elucidate major clades within Apiaceae (Umbelliferae) subfamily Apioideae Drude. This paper summarizes the results of previously published molecular cladistic analyses and presents a provisional classification of the subfamily based on taxonomic congruence among the data sets. Ten tribes (Aciphylleae M. F. Watson & S. R. Downie, Bupleureae Spreng., Careae Baill., Echinophoreae Benth., Heteromorpheae M. F. Watson & S. R. Downie, Oenantheae Dumort., Pleurospermeae M. F. Watson & S. R. Downie, Pyramidoptereae Boiss., Scandiceae Spreng. and Smyrnieae Spreng.) are erected or confirmed as monophyletic, with Scandiceae comprising subtribes Daucinae Dumort., Scandicinae Tausch and Torilidinae Dumort. Seven additional clades are also recognized but have yet to be treated formally, and at least 23 genera examined to date are of dubious tribal or clade placement. The utility of these different molecular markers for phylogenetic inference in Apioideae is compared based on maximum parsimony analyses of subsets of previously published molecular data sets. Of the six loci sequenced, the ITS region is seen to be evolving most rapidly and rbcL is the most conservative. Intermediate in rate of evolution are matK and the three chloroplast introns; with rpl16 and rps16 evolving slightly faster than matK or rpoC1. The analysis of restriction sites, however, provided 2–4 times more parsimony informative characters than any single DNA locus sequenced, with estimates of divergence just slightly lower than that of the ITS region. The trees obtained from separate analyses of these reduced data sets are consistent with regard to the major clades inferred and the relationships among them. Similar phylogenies are obtained by combining data or combining trees, representing the supermatrix and supertree approaches to phylogenetic analysis, respectively. The inferred relationship among the tribes and informally recognized major clades within Apioideae is presented.

(Received January 27 2000)
(Accepted October 1 2000)


Key Words: Chloroplast intron; internal transcribed spacer; molecular systematics; nuclear rDNA; phylogeny; suprageneric classification; Umbelliferae.