Organic fertilization and composition of oregano essential oil

Abstract

Origanum vulgare L. better known as oregano or marjoram in Europe and Brazil is a herbaceous plant which determines long-range chemical and morphological diversity. The composition of essential oil of herbs like oregano, depends on different factors such as climate, geographical origin, harvest season, nutrition that can significantly affect the oil production and quality. The objective of this work was investigate the oregano oil production and composition in differents conditions of crops and seasons in Cerrado of Brazil. The experimental was a randomized block design (RBD) in a factorial 2 x 2 x 2 with five replications, two systems of planting (greenhouse and field), two types of fertilizers (mineral and organic) and two seasons (autumn and spring). The results of essential oil presented the same composition for all the treatments. However, the relative proportion of some chemical constituents was altered according to the planting in greenhouse or in field and organic or mineral fertilizer. Carvacrol, terpinene, ortho-cymene were the major constituents. The spring season and the field conditions favored better essential oil yield and carvacrol production.