Vegetative propagation protocol of Hedeoma teyucuarensis endemic medicinal species in danger of extinction

Abstract

Hedeoma teyucuarensis is a microendemic species of the only fragment of the Cerrado Biome of Argentina developed on sandstones. It is critically endangered because it is used in folk medicine to combat intestinal parasites. The aim of the present study is to evaluate the feasibility of obtaining H. teyucuarensis mother plants from cuttings, using different concentrations of 1-naphthaleneacetic acid (NAA) in sand, perlite, and pine bark. Cuttings are harvested from plants located in its natural distribution area (San Ignacio, Misiones, Argentina). Subsequently, apical and subapical cuttings 7 cm long are obtained from the harvested plant material. The bases of these are immersed in a solution of NAA at doses of 0, 100 and 250 mg/kg-1for 30 minutes and then in a fungal solution for 20 minutes. The cuttings are placed in 200 cm3pots containing sand, perlite, and pine bark as substrate. The highest percentage of rooting is obtained in the cuttings of the control treatment. The concentration of NAA did not affect the rooting percentage but did affect the number of roots. This work has shown that the type of stake and substrate used affects rooting and therefore the obtaining of plants. This study provides a methodology of vegetative propagation to obtain plants, which can be used to conserve this endangered species.