Abstract:The essential oil composition of Peumus boldus and Drimys winterii was analyzed by means of capillary GC-FID and GC-MS. More than 96% of the total oil components (43 and 54 compounds, respectively) were identified, with ascaridole (51.17 ± 9.51), p-cymene (16.31 ± 2.52) and 1,8-cineole (14.45 ± 2.99) as the main compounds in P. boldus and -eudesmol (21.65 ± 0.41), followed of elemol (12.03 ± 0.34) and terpinen-4-ol (11.56 ± 1.06) in D. winterii. The herbicidal activity was tested against Amaranthus hybridus and Portulaca oleracea. P. boldus essential oil was the most phytotoxic against both weeds, inhibiting seed germination and seedling growth at all concentrations assayed (0.125-1 µL/mL). D. winterii essential oil did not show any effect on A. hybridus germination and only affected P. oleracea germination at the highest concentration. The results suggest the possible use of the essential oil from P. boldus as a natural herbicide.

The chemical composition of essential oils from Satureja cuneifolia growing in east Spain was analyzed by GC, GC/MS. Forty-five compounds accounting for 99.1% of the total oil were identified. Camphor (47.6%), followed by camphene (13.6%) were the main compounds. Their herbicidal and antifungal activity was tested in vitro against three weeds (Amaranthus hybridus, Portulaca oleracea and Conyza canadensis) and eleven common pathogenic or saprophytic fungi (Phytophthora citrophthora, P. palmivora, Pythium litorale, Verticillium dahlia, Rhizoctonia solani, Penicillium hirsutum, Colletotrichum gloeosporioides, Phaeoacremonium aleophilum, Phaemoniella chlamydospora, Cylindrocarpon liriodendri and C. macrodidymum). The essential oil was very active against A. hybridus and C. canadensis significantly inhibiting their germination and seedling growth. Minor activity was shown against P. oleracea, depending on the concentration applied. P. palmivora, P. citrophthora and Pa. chlamydospora were the most sensitive fungi to the treatment with the essential oil, whereas R. solani showed no inhibition. Results showed that S. cuneifolia essential oil could be used for biocontrol of weeds and fungal plant diseases.