Univrsity of Tehran Press Iranian Journal of Field Crop Science 2008-4811 56 1 2025 03 21 The Effects of Fe Fertilizer and Humic Acid on the Two Superior Rainfed Safflower Cultivars The Effects of Fe Fertilizer and Humic Acid on the Two Superior Rainfed Safflower Cultivars 143 155 101562 10.22059/ijfcs.2024.376438.655080 FA Aydin Tobeh Department of Plant Production and Genetics, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran. 0009-0004-6839-7208 Ahmad Tobeh Department of Plant Production and Genetics, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran. Salim Farzaneh Department of Plant Production and Genetics, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran. 0000-0003-1695-5592 Journal Article 2024 05 14 To evaluate the effects of two types of fertilizers (iron fertilizer and humic acid) on the yield and physiological traits of two safflower cultivars, this research was conducted during the 2021–2022 growing season at the Agricultural Research Center of Ardabil. The main factor consisted of two safflower cultivars: Goldasht and Chinese (XYS). The experiment was arranged as a split-plot design within a randomized complete block framework with three replications. The sub-factor was fertilizer application with nine levels, including a control group, two levels of 95% humic acid (2 mg/L and 4 mg/L), two levels of 12% EDTA-chelated iron fertilizer (1 mg/L and 2 mg/L), and four levels of combined iron and humic acid fertilizers. Observations showed that the Goldasht cultivar, with a yield of 1462.5 kg/ha, significantly outperformed the Chinese cultivar, which yielded 1406.3 kg/ha. Among the fertilizer treatments, the highest yield (1694.1 kg/ha) was achieved with the combined application of the second level of iron fertilizer and the second level of humic acid. None of the treatments had a significant effect on seed oil percentage. It was observed that the combined foliar application of the second levels of both iron and humic acid fertilizers resulted in the highest chlorophyll content both before and after flowering, with values of 66 and 55.3, respectively. Overall, the Goldasht cultivar outperformed the Chinese cultivar, and among the fertilizer treatments, the combined application of the second levels of iron and humic acid fertilizers was identified as the most effective treatment. To evaluate the effects of two types of fertilizers (iron fertilizer and humic acid) on the yield and physiological traits of two safflower cultivars, this research was conducted during the 2021–2022 growing season at the Agricultural Research Center of Ardabil. The main factor consisted of two safflower cultivars: Goldasht and Chinese (XYS). The experiment was arranged as a split-plot design within a randomized complete block framework with three replications. The sub-factor was fertilizer application with nine levels, including a control group, two levels of 95% humic acid (2 mg/L and 4 mg/L), two levels of 12% EDTA-chelated iron fertilizer (1 mg/L and 2 mg/L), and four levels of combined iron and humic acid fertilizers. Observations showed that the Goldasht cultivar, with a yield of 1462.5 kg/ha, significantly outperformed the Chinese cultivar, which yielded 1406.3 kg/ha. Among the fertilizer treatments, the highest yield (1694.1 kg/ha) was achieved with the combined application of the second level of iron fertilizer and the second level of humic acid. None of the treatments had a significant effect on seed oil percentage. It was observed that the combined foliar application of the second levels of both iron and humic acid fertilizers resulted in the highest chlorophyll content both before and after flowering, with values of 66 and 55.3, respectively. Overall, the Goldasht cultivar outperformed the Chinese cultivar, and among the fertilizer treatments, the combined application of the second levels of iron and humic acid fertilizers was identified as the most effective treatment. https://ijfcs.ut.ac.ir/article_101562_d06689b9dd27dd877ffc0d663b445f85.pdf