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Phyllotaxis in vegetative shoots and lamina rotation of Magnoliaceae are described. Most genera in Magnoliaceae investigated (except Parakmeria, Manglietiastrum and Pachylarnax) show lamina rotation. Paraphoric, a new type of lamina rotation differing from four other types depicted by Charlton is clarified. Manglietia, Parakmeria, Manglietiastrum, Talauma, section Gwillimia and Rytidospermum in subgenus Magnolia, shoots of Woonyoungia, section Theorhodon and Liriodendron have spiral phyllotaxis, however Magnolia section Oyama and Maingola, Alcimandra, Michelia, Paramichelia, Tsoogiodendron, buds of Woonyoungia, section Theorhodon and Liriodendron have distichous phyllotaxis. The systematic implication of vegetative shoot phyllotaxis and lamina rotation in Magnoliaceae is discussed in this paper.

The ndhF sequences of 99 taxa, representing all sections in extant Magnoliaceae, were analyzed to address phylogenetic questions in the family. Magnolia macrophylla and M. dealbata, North American species of Magnolia section Rytidospermum, are placed at the base in the subfamily Magnolioideae although its supporting value is low. In the remaining taxa, several distinctive lineages are recognized: (1) Magnolia, the biggest genus in the family, is not monophyletic; (2) Michelia, including section Maingola of Magnolia subgenus Magnolia, is closely related with Elmerrillia and sections Alcimandra and Aromadendron of Magnolia subgenus Magnolia; (3) the associates of Michelia are grouped with Magnolia subgenus Yulania and section Gynopodium of Magnolia subgenus Magnolia; (4) Pachylarnax forms a clade with sections Manglietiastrum and Gynopodium of Magnolia; (5) a well-supported Manglietia clade is recognized; (6) Caribbean species of section Theorhodon of Magnolia subgenus Magnolia, which are section Splendentes sensu Vazquez-Garcia, are closely allied with New World members of Magnolia subgenus Talauma; and (7) section Rytidospermum of Magnolia subgenus Magnolia and subgenus Talauma are polyphyletic. The separated clades in the molecular tree are considerably different from traditional taxonomic dispositions in the family. The molecular data strongly suggest that a taxonomic realignment of infrafamilial delimitations and compositions should be considered.