ESSENTIAL OIL COMPOSITION OF ARISTOLOCHIA CHILENSIS A HOST PLANT OF BATTUS POLYDAMAS

Abstract

In this communication we report the essential oil composition of Aristolochia chilensis Bridges ex Lindl. fresh leaves. This species is one of the larval food-plants of Battus polydamas Boisd., the only butterfly of the family Papilionidae (Lepidoptera) occurring in Chile. In order to determine possible chemical similarities among several of its host species distributed throughout the continent, we compared these results with data obtained from literature on the composition of other representative Aristolochia species occurring in Argentina, Paraguay, and Brazil. Instead of the expected, it was found that the essential oil of each species considered in this work exhibits a particular characteristic profile. 1 . Also, A. chilensis is one of the larval food-species of Battus polydamas Boisd. the only butterfly of the family Papilionidae (Lepidoptera) occurring in Chile 2,3 . Previous investigations of A. chilensis revealed the presence of aristolochic acids, 4,5-dioxoaporphines and aristolactams in its aerial parts 4-6 , and lignans as well as sesquiterpene hydrocarbons in its roots 7,8 . The essential oil of A. chilensis has not been previously studied, and the role of its volatile components in the recognition of this species as a host by the butterfly B. polydamas is not known. In this communication we report the essential oil composition of A. chilensis fresh leaves. We also compare these results with data obtained from literature on the composition of other seven Aristolochia species, distributed throughout the continent and representative to this work as they are all hosts of populations of B. polydamas 2 occurring in their distribution area. The selected species were: A. cymbifera, A.giganteae, A.macroura, and A.triangularis 9 , from Brasil; A. argentina 10 , A. gibertii 11 and A. elegans 12 , from Argentina; and again A. gibertii 13 from Paraguay. The purpose of this comparison was to determine possible chemical similarities among the essential oil of several host species of B. polydamas occurring in significantly different environments and, perhaps, elucidate common molecular candidates to host-recognition and host-acceptation kairomones for this butterfly 14 .