Leaf shape in South American Nothofagus. A combination of traditional and new methods in morphometrics

PREMOLI A.C.

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Año: 1996 p. 25 - 40

0024-4074

Leaf morphology has been the subject of several studies in Nothofagus especially in the context of the taxonomy and evolutionary relationships of taxa within the genus, which are still controversial. The leaf architecture of N. dombeyi, N. betuloides and N. nitida, dominant trees of temperate forest in southern South America, is compared using venation patterns, landmarks, and entire outlines. In terms of venation patterns N. dombeyi and N. betuloides were more similar to each other than to N. nitida. Similar results were found when differences in shape were analysed by discriminant analyses of shape coordinates (landmarks) and Fourier coefficients (outlines). For both analyses, the first discriminant function separated N. nitida from the other two species; these were also distinguished but showed greater overlap with each other. This study, in concert with information from allozyme data confirms the hypothesis of a more ancestral position for N. nitida with N. dombeyi and N. betuloides being more recently derived. In addition to differences in shape, the size component of leaf morphology indicated that whereas N. betuloides had the smallest leaves, N. dombeyi spanned the greatest range and has the biggest leaves. Giventhat the data shown here were obtained from seedlings grown under common-garden conditions,differences in both shape and size, seem to be important components of leaf morphology that may warrant consideration in characterizing these and other species of Nothofagus.