Abstract
Pots experiment was carried out in the greenhouse of Horticulture Department College of Agriculture Engineering Sciences/ University of Duhok to investigate the influence of three levels of P2O5 fertilizer (0, 260 and 520 mg ) per pot , humic acid at (0, 0.6 and 0.8 mg.L-1) and magnetic water with three group, group (1) irrigated with tap water, group (2) irrigated with magnetized water remain in the container for 12 hours and group (3) irrigated with magnetized water remain in the container for 24 hours on the growth and oil yield of Black cumin Nigella sativa L. The experimental treatments consisted of five replications in Random Complete Block Design (RCBD). The results revealed that P2O5 fertilizer at 520 mg.pot-1 significantly increased all the studied characteristics. Humic acid at 0.6 and 0.8 mg.L-1 had no significant effect on most of the studied characteristics except total chlorophyll and volatile oil. The group of plants that irrigated with magnetic water for 24 h caused significant increasing in all studied characteristics. Double and triple interactions among studies factors showed significant influence on all the studied characteristics as compared to untreated plants including (plant height, number of branches per plant, stem diameter, number of capsule/plant, dry weight, total chlorophyll, fixed oil percentage, volatile oil percentage and total carbohydrates percentage).