Ontogenetic studies of the nutlets in some Mentha species (Lamiaceae) from Argentina

BONZANI, N.; BRAVI, V. & G. BARBOZA

Sao Paulo

Congreso; XX Simpósio de Plantas Medicinais do Brasil & X International Congress of Ethnopharmacology; 2008

Universidade Federale Sao Paulo, Universidade Federale RGS, Sociedade Brasileira de Plantas Medicinales

Ontogenetic studies of the nutlets in some Mentha species (Lamiaceae) from Argentina Bonzani, N., Bravi, V. and G. Barboza Bonzani, N., Bravi, V. and G. Barboza Instituto Multidisciplinario de Biología Vegetal (CONICET-Universidad Nacional de Córdoba), and Facultad Cs. Químicas (UNC). Córdoba, Argentina. nbonzani@imbiv.unc.edu.ar Instituto Multidisciplinario de Biología Vegetal (CONICET-Universidad Nacional de Córdoba), and Facultad Cs. Químicas (UNC). Córdoba, Argentina. nbonzani@imbiv.unc.edu.ar Mentha L. (subfam. Nepetoideae) is naturalized in Argentina with 5 species (Bonzani et al. 2007), which are used as folk remedies, in medicine, in phytoteraphy, and in many commercial industries (Lawrence, 2006). As part of a broad study to contribute to the delimitation of the species and quality control as herbal drug (Bonzani et al. 2007), we deal in this opportunity with the ontogenetic aspects of the nutlets and analysis of the myxocarpy phenomenon in the Argentinean Mentha species (M. citrata Ehrh., M. spicata L., M. pulegium L., M. x piperita L., M. x rotundifolia (L.) Hudson. Cross and longitudinal section of the gynoecium pre- and postfertilization up to mature fruit were carried out according to D’Ambrogio de Argüeso (1986) techniques. Myxocarpy has been tested after Mosquero et al. (2006). The species showed several morphological and anatomical differences, such as the shape and ornamentation of the nutlets, the type of cells in the epicarp, and the shape and type of sclereids (differential width of the cell walls and size of the lumen) in the mesocarp. The most relevant and constant features are: the presence of a gynophoric nectary (nectary at the base of the ovary which extends to the short gynophore), the mesogyne style, the constant number of layer in the pericarp, the sinuate cell walls of the sclereids in surface view, and the sclereids arranged in a palisade layer with a prismatic crystal inside in cross section. The myxocarp is confirmed in all the species with a weak but distinct to moderately strong mucilaginous reaction. The results are discussed within the subfamily context (Duletiæ-Lauševiæ & Marin, 1999). Thanks to Secyt-UNC for financial support. Mentha L. (subfam. Nepetoideae) is naturalized in Argentina with 5 species (Bonzani et al. 2007), which are used as folk remedies, in medicine, in phytoteraphy, and in many commercial industries (Lawrence, 2006). As part of a broad study to contribute to the delimitation of the species and quality control as herbal drug (Bonzani et al. 2007), we deal in this opportunity with the ontogenetic aspects of the nutlets and analysis of the myxocarpy phenomenon in the Argentinean Mentha species (M. citrata Ehrh., M. spicata L., M. pulegium L., M. x piperita L., M. x rotundifolia (L.) Hudson. Cross and longitudinal section of the gynoecium pre- and postfertilization up to mature fruit were carried out according to D’Ambrogio de Argüeso (1986) techniques. Myxocarpy has been tested after Mosquero et al. (2006). The species showed several morphological and anatomical differences, such as the shape and ornamentation of the nutlets, the type of cells in the epicarp, and the shape and type of sclereids (differential width of the cell walls and size of the lumen) in the mesocarp. The most relevant and constant features are: the presence of a gynophoric nectary (nectary at the base of the ovary which extends to the short gynophore), the mesogyne style, the constant number of layer in the pericarp, the sinuate cell walls of the sclereids in surface view, and the sclereids arranged in a palisade layer with a prismatic crystal inside in cross section. The myxocarp is confirmed in all the species with a weak but distinct to moderately strong mucilaginous reaction. The results are discussed within the subfamily context (Duletiæ-Lauševiæ & Marin, 1999). Thanks to Secyt-UNC for financial support. Duletiæ-Lauševiæ, S. & P. Marin. Nordic J. Bot. 19: 435. 1999 Lawrence, B. Mint: The genus Mentha. 2006. Bonzani, N. et al. Arnaldoa 14: 77. 2007 D’Ambrogio de Argüeso, A. Manual de Técnicas en Histología Vegetal. 1986 Mosquero, M. et al. Lagascalia 27: 13. 2006