Phylogenetic relationships of Deschampsia antarctica (Poaceae): Insights from nuclear ribosomal ITS.

D. P. FERNANDEZ SOUTO, S. A. CATALANO, D. TOSTO, P. BERNASCONI, A. SALA, M. WAGNER, AND D. CORACH.

PLANT SYSTEMATICS AND EVOLUTION

Año: 2006 vol. 261 p. 1 - 9

0378-2697

Deschampsia antarctica. E. Desv. Is the only monocot in the Antartic floristic zone.  We evaluated the phylogenetic relationship of  Deschampsia antarctica to otheer grasses using parsimony as the optimatily criterion. Five different sets of gap, transversion and transitions costs were explored to analyze the effect of parameter choice on the phylogenetic results.. Both internal transcribed spacers (ITS1 and ITS2) and the 5.8S subunit of nuclear ribosomal DNA were included in the analysis. A totalof 43 species were analyzed including seven species of Deschmpsia. Deschampsia Antarctica forms a well supported group with five species of deschampsia. Deschampsia does not appear monophyletic as D. flexuosa (L) Trin. Is not included in this clade. The clade to which D. Antarctica belongs is sister to some Avenae in all analyses. This study is the first contribution that evaluates the phylogenetic position  of D. Antarctica in relation to other species of Deschampsia.