Caracterização de germoplasma e armazenamento de patchouli (Pogostemon sp.)

Abstract

The species Pogostemon cablin Benth. – Lamiaceae can be detached between the species of this genus because of the production of essential oil extracted from the dried leaves, which possesses medicinal, repellent and insecticide properties and is principally important for the perfume industry. The aim of this work was to install an Active Germplasm Bank of patchouli (Pogostemon sp.) at the Research Farm "Campus Rural da UFS", to evaluate the morphologic, agronomic and chemical characterization of the accessions, besides to test the influence of storage time of dry leaves on the essential oil content and chemical composition. The first chapter presents the general introduction, the literature review of botany and use of species of the genus Pogostemon, essential oil of P. cablin, conservation and morphological, agronomic and chemical characterization of vegetative germplasm, cultivation and post-harvest of P. cablin, and sustainability of agroecosystems. The second chapter presents and discusses the data of the morphological and agronomic characterization of 10 Pogostemon accessions of the Active Germplasm Bank (AGB) of the Universidade Federal de Sergipe (UFS) harvested in four seasons, may, august and november 2008 and february 2009. Variation between Pogostemon sp. accessions of the AGB of the UFS was observed for all qualitative morphologic characteristics. The descriptors color of stalks, veins, sepals and petals, and pilosity of leaves contributed to distinguish the accessions POG-001 and POG-006 from the others, which suggest that these two accessions are another species and not P. cablin. Significative differences between accessions were observed for the quantitative characteristics evaluated at each harvest, with exception for length of leaves (first harvest), essential oil yield (second harvest) and canopy diameter (third harvest). In the third chapter the chemical variation of the essential oil of 10 Pogostemon accessions of the AGB of the UFS, harvested in four seasons. Patchoulol was the major compound at the four harvests of all the P. cablin accessions. The principal compound of the accessions POG-001 and POG-006 was β-pinene. Two groups were detected by the multivariate analyses at the four harvests. Group 1 was formed by the accessions POG-001 and POG-006 (Pogostemon sp.), and group 2 was formed by the accessions of P. cablin (POG-002, POG-014, POG-015, POG-016, POG-017, POG-019, POG-021 and POG-022). In the fourth chapter the influence of storage time (0, 3, 7, 14 and 28 days) of dried leaves was analyzed on the essential oil content and chemical composition of two P. cablin accessions (POG-002 and POG-021) of the AGB of the UFS. Storage influenced significatively the essential oil content of accession POG-002. Patchoulol was the majority compound. Storage of dry leaves increased significatively the content of the compounds α-bulnesene (14 days) and germacrene A (3 and 7 days) at accession POG-021 and longicanfenilone (28 days), pogostol and patchoulol (3, 7, 14 and 28 days) at accession POG-002. However reduced significatively the content of the compounds cicloseichelene, β-cariofilene, α-guaiene, acifilene and α-bulnesene of the essential oil of the accession POG-002.