Effect of Different Levels of Pruning and Nitrogen Fertilizer on the Quality and Quantity of the Volatile Oil of Rosmarinus officinalis L.

Abstract The experiment was performed in a greenhouse belonging to the Department of Horticulture and Landscaping gardening, College Agriculture, Tikrit University from November 2021 - May 2022. included two factors: level pruning (without pruning, moderate severe pruning); addition nitrogen fertilizer at levels (73.4 146.7 g N.L -1 form urea (46% N) according randomized complete block design (RCBD). results showed that fertilization treatment (F2) significantly excelled quantity oil (2.505 g. 50 plant ) specific weight (0.907 g.ml an increase active substances (Cinol, Limonene, α-Pinene), which amounted (32.701, 4.476, 8.407 mg. ).