Abstract:

The molecular phylogenetics of sect. Parrya Myre of Pinus L. was analyzed based on chloroplast matK gene sequence data. The section was resolved as paraphyletic because members of the sect. Strobus were nested within a clade composed by the Asian members of the section, including the Vietnamese P. krempfii Lecomte, which was strongly supported with a bootstrap value of 92%. In this topology, the three sampled species of sect. Strobus formed a strongly supported monophyletic group, while their relationships of Asian species of sect. Parrya were not clear. P. krempfii was grouped with P. gerardiana Wall. ex D. Don with low bootstrap support. The relationships among the Asian members of the sect. Parrya, i.e. P. bungeana Zucc. ex Loud., P. gerardiana and the recently described endangered pine, P. squamata X. W. Li, was not resolved, although the monophyly of the three pines was strongly supported in the combined analysis of four cpDNA sequences. The topology of the neighbor joining tree revealed an assemblage of the American members of the section, which also appeared in the majority rule tree with weak bootstrap support. However, this assemblage was not resolved in the consensus tree of the parsimonious analysis. The American subsect. Balfourianae Engelm. formed a weakly supported group including P. aristata Engelm., while the relationships among and within the other two American subsections, Cembroides Englem. and Rzedowskianae Carv., were not resolved, as the members of them formed a polytomy in the consensus tree of the parsimonious analysis. The biogeographical implications of the results are also discussed in this paper.

Key words: Sect. Parrya Mayr, Pinus, molecular phylogeny, matK gene