Hidrosystem anatomical features of principal woody plants of Chaco, Argentina

Abstract

Selected wood anatomy characteres of fourty six species of the principal trees of the Chaco Region were studied in order to analyze the hydraulic conductivity and safety of the xylem system, and compared with data from other habitats. Wood microscopic features considered were: ring porosity, vessel arrangement, tangential vessel diameter, number of vessels per mm2, Vulnerability Index, vessel element length, perforation plate, helical thickening and tracheas. A predominance of characters that probably contribute to hydraulic safety was observed: diffuse porous, numerous grouped or multiple vessels of small diameter, short vessel elements, with simple perforation plate. Maytenus vitis-idaea, Rupretchia apetala, Castela coccinea, Parkinsonia aculeata, Jodina rhombifolia species of the driest part of Chaco Region, present the most xerophytic features.