Characterization of some Italian types of wild fennel (Foeniculum vulgare Mill.).

Wild samples of Foeniculum vulgare Mill. (fennel) were collected from thirteen Italian localities at different latitudes and grown in field trials to evaluate their morphological and agronomic characteristics and essential oil compositions. All the parameters were recorded at full bloom stage, and the essential oils (obtained by steam distillation) were characterized by gas chromatography (GC) and GC/mass spectrometry (GC/MS). The morphological characteristics showed positive relations among the number of umbels per plant, the plant weight, and the umbel weight percentage, and between these three parameters and the oil content. The essential oils evidenced five chemical groups characterized by (1) alpha-phellandrene, methyl chavicol, and trans-anethole; (2) alpha-pinene, limonene, and trans-anethole; (3) methyl chavicol and alpha-phellandrene; (4) methyl chavicol and alpha-pinene; and (5) alpha-phellandrene.