Reappraisal of vegetative morphology and architecture in plant differentiation: the case of South American Nothofagus.

PUNTIERI, JAVIER GUIDO; STECCONI, MARINA; GROSFELD, JAVIER; BRION, CECILIA; GHIRARDI, SOLEDAD; TORRES, CRISTIAN; BARTHÉLÉMY, DANIEL

Bariloche

Congreso; Southern Connection Congress; 2010

CONICET, Universidad Nacional del Comahue

Since early botanical research, the relevance of reproductive morphological traits for species differentiation has been emphasized, with the explicit argument that such traits exhibit little variablility. Simultaneously, variability of vegetative morphology following environmental factors has been highlighted. But in recent decades, plant vegetative traits have been used with success in the evaluation of plant form and its mathematical modelling. Here we reassess the role of vegetative-morphological and architectural traits in the differentiation of South American Nothofagus species. For these species, the morphological criteria most frequently used so far have been, almost exclusively, leaf and reproductive traits. A promising use of vegetative morpho-architectural traits for the descrimination of Nothofagus species must start with the identification of: (a) the ontogenetic stages of the species concerned, (b) the structural units making up the individuals (metamers, growth units, annual shoots and axes), (c) the morphogenetic gradients linking the structural units among them and (d) the nature of the reiterations these species develop.