Caracterização morfo-anatômica e metabólica de espécies do gênero Cymbopogon: uma contribuição para o melhoramento das espécies

Abstract

Medicinal plants have always been used by humans as an alternative in the fight against diseases. To avoid the use of species wrongly, is necessary perform the correct identification of plants of interest, as well as meet morphological, anatomical and even metabolic details, enabling the differentiation of species in a correct and safe manner. The objective this work was to identify botanical, morphological, anatomical and chemistry traits of plants of the genus Cymbopogon, establishing specific traits of each species, for future use in a breeding program and for plant growers medicinal products. The growth was conducted at plantbed located in the Capão do Leão – RS city on the campus of the Universidade Federal de Pelotas, in the years of 2016/2017, being used Cymbopogon citratus, Cymbopogon distans, Cymbopogon flexuosus and Cymbopogon winterianus species. This study described some morphological traits (plant height, leaf length and leaf width and stem length), anatomical traits (stoma index and size, transversal cuts of the main vein) and the chemical profile of the four species (volatile and non-volatile compounds present infusions and essential oil). The studied species show several structural traits in common, however, leaf size (width and length), arrangement and size of the midrib, size and location of the stomata, are of great importance for the differentiation. Based on the analyzes carried out in this study, it was concluded that, in general, the C. distans specie presented a greater number of distinct traits, differing in plant height, leaf size, number and location of stomata, arrangement of conducting vessels and chemical profile of the essential oil, being distinguished by its high levels of citral. C. citratus, C. flexuosus and C. winterianus species presented several morphological and anatomical traits in common, making the metabolome analysis an effective tool for species discrimination. In the analysis of the infusions, C. flexuosus showed a differentiated chemical profile, with small number of compounds identified. As for the essential oil, it was possible to identify the citral as the main component of C. citratus, C. distans and C. flexuosus. Citronellal, citronellol, geraniol and elemol are predominant in C. winterianus. The C. citratus specie is distinguished by the high concentration of myrcene, which distinguishes it from C. flexuosus, which are known by the same popular name.