Iranian Medicinal Plants Society Journal of Medicinal plants and By-products 2322-1399 8 2 2019 09 01 Effects of Fertilizer Treatments on Antioxidant Activities and Physiological Traits of Basil (Ocimum basilicum L.) under Water Limitation Conditions 143 151 120492 10.22092/jmpb.2019.120492 EN Hassan Mahdavikia Department of Medicinal Plants, Shahid Bakeri Higher Education Center of Miandoab, Urmia University, Urmia, Iran Esmaeil Rezaei-Chiyaneh Department of Plant Production and Genetics, Faculty of Agriculture and Natural Resources, Urmia University, Urmia, Iran Amir Rahimi Department of Plant Production and Genetics, Faculty of Agriculture and Natural Resources, Urmia University, Urmia, Iran Nayer Mohammadkhani Department of Medicinal Plants, Shahid Bakeri Higher Education Center of Miandoab, Urmia University, Urmia, Iran Journal Article 2018 12 05 Drought stress is a major environmental stress that restricts plant growth and production in the majority of agricultural fields of the world. The application of different fertilizers, especially biofertilizers and organic fertilizers, might play an important role in the production of medicinal plants in order to improve their resistance to deficit water stress. In order to evaluate the effects of fertilizer treatments on antioxidant enzyme activity and physiological characteristics of basils (<em>Ocimum basilicum</em> L.) under water-limited conditions, a study was arranged as a factorial layout based on a randomized complete block design with three replications. Two irrigation intervals (6, and 12 days) and six fertilizers levels [chemical fertilizers (N, P, K), vermicompost (10 t  ha^-1) + mycorrhizal fungi (<em>Glomus intraradices</em>), vermicompost +bacterial biofertilizer [Azetobarvar1 (<em>Azotobacter vinelandii </em>as nitrogen-fixing bacteria), Phosphatebarvar2 (<em>Pseudomonas putida </em>and <em>Bacillus lentus </em>as phosphorus solubilizing bacteria), Pota barvar-2 (<em>Pseudomonas koreensis </em>and <em>Pseudomonas vancouverensis </em>as potassium releasing bacteria)], bacterial biofertilizer+mycorrhizal fungi, chemical fertilizers 50% (Basic NPK fertilizer was applied at the rate of 90–120–100 kg/ha in the form of urea, triple super phosphate, and potassium sulfate, respectively)+ bacterial biofertilizer and control] were assigned as the first and second experimental factors, respectively. The results showed that water limitation decreased the chlorophyll content and relative water content, but carotenoids and antioxidantenzyme activities (catalase, superoxide dismutase, and peroxidase) and also osmolytes (proline and sugar) contents were increased. But, the application of fertilizer sources alleviated the drought effects, so the application of fertilizers (especially chemical fertilizers 50% + bacterial biofertilizer) increased these traits at all irrigation levels. Overall, in addition to cellular mechanisms, such as osmoregulation and antioxidant defense, fertilizers sources application can improve antioxidant activities and physiological traits of basil under water-limited conditions. https://jmpb.areeo.ac.ir/article_120492_05cc6b6e2cf2ab17ed3e87dd14ddd0a1.pdf