Ecological foliar fertilization effects on essential oil composition of sweet basil (Ocimum basilicum L.) cultivated in a field system

Ocimum basilicum L. (basil) is a valuable aromatic plant, widely used in traditional and modern medicine, perfumery, the food industry, cosmetics and landscaping. In order to study the effect of organic foliar fertilization on essential oil (EO) content and composition, a field experiment was conducted. Treatments including four different organic foliar fertilizers: Fylo® (F1), Geolino Plants&Flowers® (F2), Cropmax® (F3), Fitokondi® (F4) and control were set up in a factorial experiment based on split plot design with three replications. Recovery of the EO ranged from 0.2% to 0.42% for basil leaves and 0.52-0.69% for basil flowers. GC-MS analysis of the essential oils revealed the presence of linalool, α-muurolol, methyl chavicol, eugenol, γ-cadinene, α-bergamotene, eucalyptol, germacrene D, cubenol, β-elemene and α-bulnesene as main compounds in all the samples but their percentages in each part of the plant (leaves and flowers) were greatly different. Moreover, certain variations in the content of particular compounds in EO were found, depending on the fertilization applied. Accordingly, it can be concluded that organic foliar fertilization can considerably improve the essential oil content, without drastic effects on the chemical composition.