Phylogenetic relationships in Rosaceae inferred from chloroplast matK and trnL-trnF nucleotide sequence data

 Phylogenetic relationships in Rosaceae were studied using parsimony analysis of nucleotide sequence data from two regions of the chloroplast genome, the matK gene and the trnL-trnF region. As in a previously published phylogeny of Rosaceae based upon rbcL sequences, monophyletic groups were resolved that correspond, with some modifications, to subfamilies Maloideae and Rosoideae, but Spiraeoideae were polyphyletic. Three main lineages appear to have diverged early in the evolution of the family: 1) Rosoideae sensu stricto, including taxa with a base chromosome number of 7 (occasionally 8); 2) actinorhizal Rosaceae, a group of taxa that engage in symbiotic nitrogen fixation; and 3) the rest of the family. The spiraeoid genus Gillenia, not included in the rbcL study, was strongly supported as the sister taxon to Maloideae sensu lato. A New World origin of Maloideae is suggested. The position of the economically important genus Prunus and the status of subfamily Amygdaloideae remain unresolved. Received February 27, 2001 Accepted October 11, 2001     

Phylogeny and Classification of Prunus sensu lato （Rosaceae）

The classification of the economically important genus Prunus L. sensu lato （s.L） is controversial due to the high levels of convergent or the parallel evolution of morphological characters. In the present study, phylogenetic analyses of fifteen main segregates of Prunus s.I. represented by eighty-four species were conducted with maximum parsimony and Bayesian approaches using twelve chloroplast regions （atpB- rbcL, matK, ndhF, psbA-trnH, rbcL, rpL 16, rpoC1, rps16, trnS-G, trnL, trnL-F and ycfl） and three nuclear genes （ITS, s6pdh and Sbel） to explore their infrageneric used to develop a new, phylogeny-based classification relationships. The results of these analyses were of Prunus s.I. Our phylogenetic reconstructions resolved three main clades of Prunus s.I. with strong supports. We adopted a broad-sensed genus, Prunus, and recognised three subgenera corresponding to the three main clades： subgenus Padus, subgenus Cerasus and subgenus Prunus. Seven sections of subgenus Prunus were recognised. The dwarf cherries, which were previously assigned to subgenus Cerasus, were included in this subgenus Prunus. One new section name, Prunus L. subgenus Prunus section Persicae （T. T. yu ＆ L. T. Lu） S. L. Zhou and one new species name, Prunus tianshanica （Pojarkov） S. Shi, were proposed.