Phylogenetic analysis of Papaver L.

Abstract

The phylogenetic relationships of Papaver L. were investigated using morphological, molecular and phytochemical characters. Such information is of great utility because Papaver species produce highly valuable secondary metabolites, including morphine thebaine and codeine. Two molecular regions have been implemented in this analysis, the internal transcribed spacer region (ITS) of 18S-26S nuclear ribosomal DNA and the trnL intron and the trnF intergenic spacer region of plastid origin. The resulting phylogenetic trees based on parsimony analysis demonstrate that the genus is not monophyletic unless a number of closely related genera (such as Roemeria and Stylomecon) and Meconopsis cambrica are included in Papaver. Three distinct clades are resolved: Clade 1 consists of section Argemonidium and Roemeria heterophylla, Clade 2 consists of section Meconella and Clade 3 consists of all remaining sections of Papaver including Meconopsis cambrica and Stylomecon. A number of diagnostic indels and characteristic sets of nucleotide sequences support these groupings.