The Interaction Effect Between PGPR Bacteria, Mycorrhizae, and Oyster Mushroom Residues on Soil Biological Traits, Yield, and Quantity of Coriander Oil (Coriandrum sativum L.)

A factorial experiment was carried out in a sandy mixture soil using a completely randomized design (CRD) in the field of the Department of Soil Sciences and Water Resources, College of Agriculture, University of Diyala, in the agricultural season 2022-2023, in order to study the effect of adding Azotobacter, Pseudomonas, Mycorrhizae, and oyster mushroom residues in improving soil biological characteristics, quantity, and yield of aromatic oil of the medicinal coriander plant. The treatment of a mixture of bacteria and fungus residues with the presence of mycorrhizae achieved the highest amounts in oil yield, total yield, biomass carbon, numbers of Azotobacter and Pseudomonas bacteria, and the percentage of mycorrhizae infection, which recorded (153 L.ha^-1, 632.50 kg.ha^-1, 222.65 mg C kg soil^-1, 15.66 * 10⁷ CFU g^-1 dry soil, 30.00 * 10⁷ CFU g^-1 dry soil, and 90.66%), respectively, compared to the comparison treatment, which recorded (13.65 L.ha^-1, 270.50 kg.ha^-1, 133.33 mg C kg.soil^-1, 2.33 * 10⁷ CFU g^-1 dry soil, 10.00 *10⁷ CFU g^-1 dry soil, and 17.33%), respectively, and the treatment of fertilizer recommendation, which recorded (47.22 L.ha^-1, 540.00 kg.ha^-1, 150.75 mg C kg.soil^-1, 5.00 * 10⁷ CFU g^-1 dry soil, 14.66 *10⁷ CFU g^-1 dry soil, and 26.66%), respectively.