Caratterizzazione agronomica e fitochimica di ecotipi liguri e toscani di origano ( Origanum vulgare L.)

In the year 2003-2004 from some localities of the Liguria (Levant Coast) and of the Tuscany some oregano biotypes, classified as Origanum vulgare L. ssp viride (brattee greens and flowers from white to white-rose-colored), have been collected and later estimated with the aim to supply some indications about their agronomic and chemical-qualitative characteristics. The Origanum vulgare species growing in a spontaneous state, coming from Liguria and Tuscany, have been classified according to morphologic parameters (colour and dimension of the corolla, the calix, the bracts and the basal leaves). The same ecotypes have been moreover analysed in order to know quantitative content and composition of essential oils in comparison with two cultivated species of Origanum vulgare L.. The qualitative analysis contributed to characterize chemically the different biotypes, dividing in some groups; according to the high content of the biosintetic way carvacrolo-timolo or with a high content of linalolo or with a different sesquiterpenic composition. The essential oil content was studied for each sample in the vegetative phase and during the blooming phase: more elevated oil percentages were found during blooming period. This observation is clearer in the species grown spontaneously respecting to the cultivated ones. In the Laboratory of Research and Analysis of the Seeds of the Department of Agronomy and of Ecosystem management of the University of Pisa germination trials have been carried out on seeds of spontaneous and cultivated ecotypes. Regarding the germinative characteristics, it can be observed that the seeds collected from spontaneous plants show, without treatments to break dormancy, a very low percentage of germination. This does not allow a plant nursery use. On the contrary oregano seeds in the trade have shown high germination percentage without any treatment to remove dormancy.