This study aimed to verify whether the harvest time of the "Brazilian erva-cidreira" [Lippia alba (Mill.) N. E. Br.], limonene-carvone chemotype, influences leaf mass production and essential oil yield and composition. Five different harvest times were evaluated at 145 days after transplanting: 8:00, 10:00, 12:00, 14:00 and 16:00, with five replicates, distributed in randomized blocks. The experiment was carried out at Lageado Experimental Farm of the School of Agronomical Sciences FCA-UNESP/Botucatu, Horticulture Sector, Department of Plant Production. Harvest was conducted from 15 cm above the soil surface and essential oil was obtained through steam distillation in a Clevenger-type apparatus. Both the agronomical factors and the yield obtained through steam distillation were considered. The essential oil was analyzed in a gas chromatographer coupled to a mass spectrometer (GC/MS). Results were subjected to analysis of variance (F Test) and means were compared according to Tukey's test. There was no statistical difference for leaf mass production, essential oil content and essential oil yield in fresh and dry matter. However, considering the major essential oil compounds, carvone and limonene, the best yield was obtained at 10:00 for carvone in fresh (2050 L ha-1) and dry matter (2068 L ha-1), and at 16:00 for limonene in fresh (1068 L ha-1) and dry matter (1060 L ha-1).
Lippia alba; secondary metabolism; harvest time; essential oil
