University of Tehran Press Iranian Journal of Soil and Water Research 2008-479X 54 1 2023 03 21 The effect of deficit irrigation methods on growth characteristics and water productivity of safflower under Arid climate The effect of deficit irrigation methods on growth characteristics and water productivity of safflower under Arid climate 155 171 92256 10.22059/ijswr.2023.354250.669435 FA Seyed Mohammad Saeed Mousavi Department of Irrigation and Drainage, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran Mohammad Albaji Department of Irrigation and Drainage, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran Atefeh Sayadi Shahraki Department of Irrigation and Drainage, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran Mona Golabi Department of Irrigation and Drainage, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran. Mohammad Reza Moradi Telavat Department of Plant Production and Genetics, Agricultural Sciences and Natural Resources University of Khuzestan, Ahvaz, Iran Journal Article 2023 01 24 Safflower (Carthamus tinctorius L.) is a multipurpose crop that is widely grown in arid and semi-arid regions of the world, mainly to produce high-quality edible oil rich in unsaturated fatty acids. The objective of this study is to investigate the effects of regulated deficit irrigation (RDI) and partial root zone drying (PRD) methods on yield, yield components and water productivity efficiency of safflower. This study was conducted in the Experimental Research Station located in Agricultural and Natural Resources Sciences University of Khuzestan during the 2020 to 2021 and 2021 to 2022 growing seasons. The experiment was designed as a completely randomized block with one control treatment (Conventional irrigation) and 4 deficit irrigation treatments and in four replications. The results showed that the different irrigation methods had a significant and decreasing effect on plant height, number of seeds per plant, thousand seed weight, seed yield, biological yield and oil yield traits. Comparing RDI80 and PRD80 treatments, the highest seed yield (3.4 tons/ha) and oil yield (845.7 kg/ha) and the highest value of water productivity index was obtained from RDI80 treatment. Also, comparing RDI60 and PRD60 treatments, the highest seed yield (2.2 tons/ha) and oil yield (584 kg/ha) was obtained from PRD60 treatment. Therefore, according to the obtained results, it is recommended to use the RDI80 regulated deficit irrigation method to reduce 20% and the PRD60 partial root zone drying method to save 40% of water requirement for safflower cultivation in hot and dry areas with limited water resources. Safflower (Carthamus tinctorius L.) is a multipurpose crop that is widely grown in arid and semi-arid regions of the world, mainly to produce high-quality edible oil rich in unsaturated fatty acids. The objective of this study is to investigate the effects of regulated deficit irrigation (RDI) and partial root zone drying (PRD) methods on yield, yield components and water productivity efficiency of safflower. This study was conducted in the Experimental Research Station located in Agricultural and Natural Resources Sciences University of Khuzestan during the 2020 to 2021 and 2021 to 2022 growing seasons. The experiment was designed as a completely randomized block with one control treatment (Conventional irrigation) and 4 deficit irrigation treatments and in four replications. The results showed that the different irrigation methods had a significant and decreasing effect on plant height, number of seeds per plant, thousand seed weight, seed yield, biological yield and oil yield traits. Comparing RDI80 and PRD80 treatments, the highest seed yield (3.4 tons/ha) and oil yield (845.7 kg/ha) and the highest value of water productivity index was obtained from RDI80 treatment. Also, comparing RDI60 and PRD60 treatments, the highest seed yield (2.2 tons/ha) and oil yield (584 kg/ha) was obtained from PRD60 treatment. Therefore, according to the obtained results, it is recommended to use the RDI80 regulated deficit irrigation method to reduce 20% and the PRD60 partial root zone drying method to save 40% of water requirement for safflower cultivation in hot and dry areas with limited water resources. https://ijswr.ut.ac.ir/article_92256_7631cd0e77ce97bf714435284b12aa3c.pdf