Impact of Sulfur and Ammonium Sulfate on Dragonhead Plants Grown in Newly Reclaimed Soil

To determine whether dragonhead (Dracocephalum moldavica L.) could be grown successfully in arid and semiarid conditions, field experiments were done in newly reclaimed soil at Nubaria, Behira Province, west of the Nile Delta. The plants were treated with agricultural sulfur (0, 150, and 300 kg S/ha) and ammonium sulfate (0, 100, and 200 kg N/ha) using a drip irrigation system. In general, the sulfur and nitrogen treatments increased herb and essential oil yields and changed the level of secondary metabolites in dragonhead plants. Highest oil yields were obtained with agricultural sulfur at 150 kg S/ha combined with ammonium sulfate at 200 kg N/ha. The highest concentrations of geraniol in the essential oil was from plants in plots treated with agricultural sulfur at 150 and 300 kg S/ha. Ammonium sulfate at 100 kg N/ha increased the relative concentration of neral, geranyl acetate, and geraniol.