EFFECT OF ORGANIC FERTILIZER AND EGYPTIAN ROCK PHOSPHATE ON THE GROWTH, CHEMICAL COMPOSITION AND OIL PRODUCTION OF TARRAGON (Artemisia dracunculus, L.)
Journal of Productivity and Development
This study was carried out during the two successive seasons of 2004 and 2005, to investigate the response of tarragon (Artemisia dracunculus) plants to fertilization using different levels of Egyptian rock phosphate (ERP) at rates of 0, 25 or 50 kg/fad/season, and/or cattle manure (CM) at rates of 0, 20, 40 or 60 m 3 / faddan/ season. The results showed that although all the applied treatments improved the growth and yield parameters of tarragon, Egyptian rock phosphate (ERP) at 50 kg/fed.,
... ) at 50 kg/fed., combined with cattle manure (CM) at 40 m 3 /feddan proved to be the best treatment in increasing the fresh and dry herb yields (per plant and per faddan), as well as the oil percentage and oil yield. Application of ERP at 25 kg/fed., combined with CM at 40 m 3 /feddan gave the highest content of limonene in the essential oil, and decreased the estragole (which is an undesirable component) and anethol contents, compared to the control. The different CM treatments had a favourable effect on oil quality, by decreasing the estragole content. All the tested fertilization treatments tended to increase the contents of total carbohydrates in the herb. Among the three cuts harvested each season, the second cut gave the highest values for herb yield, oil percentage, oil yield, as well as the chemical parameters.