Micropropagation of the Medicinal Plant Eremanthus erythropappus (DC.) MacLeish

The aim of the present work was to establish appropriate conditions for the in vitro micropropagation of Eremanthus erythropappus (DC.) MacLeish through shoot multiplication on apical and nodal bud explants. Explants were excised from in vitro- grown seedlings and incubated on Murashige and Skoog medium containing different combinations of 6-benzylaminopurine (BAP) and 1-naphthalene acetic acid (NAA) (for apical buds) and gibberellic acid and NAA (for nodal segments). Proliferation of apical shoots was successfully achieved in the presence of BAP and NAA, each at 1.0 mg L -1 , while the elongation of apical shoots could only be attained on medium containing NAA at 1.0 mg L -1 . Elongation of nodal shoots was induced in the presence of NAA at 2.0 mg L -1 . The most suitable medium for inducing root proliferation on explants of E. erythropappus was NAA at 1.0 mg L -1 . Eremanthus erythropappus (DC.) MacLeish (Asteraceae), known in Brazil by the common name candeia, is an arboreous pioneer species distributed from the northeast of Argentina to the northern and eastern regions of Paraguay and Brazil (Carvalho, 1994). The wood of E. erythropappus is physically strong (hard) and is widely employed in the manufacture of stakes, fence posts, timber supports, and boats. The oil of the plant is also of commercial importance, being rich in the sesquiterpene a-bisabolol, and has a market value in the order of USD 60/kg (Perez, 2001). Candeia oil has anti- inflammatory properties and is also used in the production of a number of pharmaceut- icals employed in dermatology for the treat- ment of fungal and bacterial infections. Moreover, a-bisabolol can replace azulene, a monoterpene found in Chamomilla recu- tita, as a fixing agent in cosmetic products. The efficient multiplication and preserva- tion of valuable plants such as E. erythro- pappus can be achieved through in vitro micropropagation. Micropropagation of wild plants, however, can be labor-intensive and time-consuming owing to the difficulties of removing microbial contamination and of avoiding extensive oxidation of the explants. To overcome such problems, it is preferable to use explants derived from seedlings grown under aseptic conditions (Mantell et al., 1994). Because no reports are available concerning the in vitro micropropagation of E. erythropappus, we have investigated the conditions required for efficient shoot multiplication on apical bud and nodal explants obtained from seedlings cultivated aseptically.