essential oil content and composition of lemon verbena (lippia citriodora kunth.) during different phenological stages

in this study, aerial parts of lippia citriodora kunth were harvested at three phenological stages (i.e. vegetative, full flowering and fruit set). the essential oil isolated by hydro distillation for 3 h using a clevenger-type apparatus and the oil was analyzed by gc and gc-ms. the yields of oils (w/w%) in different stages was in the order of: full flowering (0.9%), vegetative (0.48%) and fruit set (0. 25%). in total, 13, 12 and 11 compounds of essential oil were identified in vegetative, full flowering and fruit set, respectively. the main compounds in three stages were geranial and neral. geranial was highest at vegetative (33.7%) and lowest at full flowering (32.7%) stages. the highest and lowest neral content was observed at vegetative (26.1%) and fruit set (25.06%) stages, respectively.