Comparative anatomy of leaves and stems in some species

MARIA DE LAS MERCEDES SOSA; GISELA M. VIA DO PICO; MASSIMILIANO DEMATTEIS

Nordic Journal of Botany

John Wiley & Sons Ltd

Año: 2014 vol. 32 p. 611 - 619

1756-1051

Vegetative anatomical features are poorly known in the South American genus Chrysolaena. In this study, leaves and stems of six Chrysolaena species were described and compared morphologically and anatomically using diaphanization, microtome serial sectioning and scanning electron microscopy. The species differed in leaf epidermis, type of stomata, shape of anticlinal walls of epidermal cells, trichome density, and presence or absence in stems of small air spaces in the cortical parenchyma and of druse-shaped oxalate crystals. Furthermore, glandular trichomes and three types of nonglandular trichomes with different number of basal cells were identified on leaves and stems. Collectively, these features proved instrumental to discriminate among the six studied species, suggesting that leaves and stems of Chrysolaena can represent a source for taxonomically useful characters. We also discuss anatomical features in relation to the environmental conditions in the species hábitats.