Phylogeny of Camellia sects. Longipedicellata,Chrysantha and Longissima(Theaceae) Based on Sequence Data of Four Chloroplast DNA Loci

Abstract

We focused on the systematic positions and relationships of three sections of Camellia subgen.Thea of Theaceae,i.e.,sect.Longipedicellata,sect.Chrysantha (golden camellias) and sect.Longissima by using four chloroplast DNA regions (rpl16,psbA-trnH,trnL-F rpl32-trnL). We sampled 28 species representing four subgenus,11 sections in Camellia and two outgroups. Combined analyses of chloroplast DNA sequence data sets are performed with the neighbor-joining,maximum-parsimony and Bayesian inference methods,and the gene trees are constructed. The topologies of gene trees revealed that:1) sect. Chrysantha is paraphyletic or polyphyletic,containing three parallel lineages and Camellia longipedicellata (type of sect.Longipedicellata) nested inside; 2) all four species from Vietnam,together with C. longipedicellata,forming a well-supported monophyletic clade,which implies the close relationship between sect.Longipedicellata and sect.Chrysantha; and 3) sect.Longissima is not monophyletic because C.hekouensis is the sister to the rest of Camellia species. The systematic position of C.longissima and the relationship between sect.Longissima and sect.Longipedicellata are unsolved.