ABSTRACT Biosynthesized from very long-chain fatty acid wax precursors, n-alkanes make a valuable contribution to the taxonomy of plants. The alkane components of foliar epicuticles of seven Neotropical species of Lecythidaceae were investigated: Bertholletia excelsa, Cariniana legalis, Couroupita guianensis, Eschweilera alvimii, Eschweilera ovata, Gustavia augusta and Lecythis pisonis. Specimens were collected in the metropolitan area of Recife, Pernambuco, and their n-alkane fractions were analyzed by gas chromatography. The chemical relationships among the species were then evaluated using cophenetic correlation and UPGMA. Among the seven species, a total of 15 n-alkanes, with 21-35 carbon atoms, were identified and formed a consistent group of B. excelsa, C. guianensis, E. ovata, G. augusta, and L. pisonis with n-C31. The greatest similarities were found between B. excelsa and L. pisonis, and between C. guianensis and G. augusta. Nevertheless, a phenetic analysis based on a larger number of species is needed to better understand the chemotaxonomic value of epicuticular n-alkanes within the Lecythidaceae.

O objetivo deste trabalho foi avaliar os perfis de n-alcanos epicuticulares foliares de genótipos de Arachis hypogaea domesticados e selvagens. Os perfis de n-alcanos epicuticulares foliares de A. hypogaea de quatro genótipos domesticados e de duas espécies selvagens - A. monticola e A. stenosperma - foram analisados por cromatografia gasosa. A similaridade química entre eles foi avaliada pelo coeficiente de Dice e pelo método UPGMA. Dois agrupamentos foram formados: um com os quatro genótipos de A. hypogaea e o outro com as duas espécies selvagens. Há maior similaridade entre os genótipos BR1 e LIGO PE06 e entre BRS 151 L-7 e BRS Havana.

The objective of this work was to analyze the epicuticular n-alkane profile of domesticated and wild peanut genotypes. Foliar epicuticular n-alkanes of four Arachis hypogaea genotypes and two wild species - A. monticola and A. stenosperma - were analyzed by gas chromatography. Chemical relationships between them were evaluated using the Dice coefficient and UPGMA method. Two clusters were formed: one with four A. hypogaea genotypes and the other with the two wild species. There is more similarity between the BR1 and LIGO-PE06 genotypes and between the BRS 151 L-7 and BRS Havana genotypes.