Biomass production and essential oil content of lemon verbena in response to organic manure application

This work evaluated the influence of organic manure in biomass production and in essential oil content of Aloysia triphylla (L'Herit) Britton. Plants growing under greenhouse received five tanned cattle manure rates: 0, 3, 6, 9 and 12 kg m-2 with four pots per replication, in randomized complete design. After 198 days of growth, plants were dried and the essential oil was extracted from leaves by the Clevenger's modified apparatus. The highest biomass was presented by plants cultivated with 12 kg m-2 and the highest oil yield was obtained from A. triphylla treated with 9 kg m-2 of cattle manure.