University of Tabriz Journal of Agricultural Science and Sustainable Production 2476-4310 Articles in Press 2027 07 22 The effect of chemical and biological fertilizers on some morphological traits and the advantages of intercropping safflower (Carthamus tinctorius) with fenugreek The effect of chemical and biological fertilizers on some morphological traits and the advantages of intercropping safflower (Carthamus tinctorius) with fenugreek 21478 10.22034/saps.2026.67916.3378 FA Yaeghoub Raei Department of Ecophysiology, Faculty og Agriculture, University of Tabriz Parisa Rostami Bonab Ph.D student of Plant Ecophysiology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran Younes Kheirizadeh Arough Department of Plant Ecophysiology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran Journal Article 2025 06 29 Intercropping systems, as a kind of sustainable production, can make better use of available resources. The experiment was carried out as a factorial experiment in a randomized complete block design with three replications at the Faculty of Agriculture's research farm in Tabriz. The experimental treatments consisted of a two-level cropping pattern (pure safflower and 100:50 additive intercropping (safflower to fenugreek)) and a six-level fertilizer treatment. (control, 100% urea recommended by soil test, foliar application of NPK, Barvar 2 phosphate + 100% urea, Barvar 2 phosphate + 50% urea, Barvar 2 phosphate + NPK). The application of 100% urea was more effective than the other treatments in increasing the grain and oil yield of safflower under pure cultivation conditions; therefore, the highest grain yield (332.6 g m-2) and oil yield (85.18 g m-2) were obtained from pure cultivation of this plant in conjunction with the application of 100% urea. However, the treatment of applying 50% urea along with Barvar 2 phosphate demonstrated the best efficiency in grain yield and oil yield under safflower and fenugreek intercropping conditions.The 100% urea application treatment had the highest land equivalency ratio (2.1), while the NPK foliar application treatment had the lowest index (1.5). According to the study's findings, the most effective nutritional treatments for boosting safflower's grain and oil yields were 50% urea + Barvar 2 phosphate in intercropping and 100% urea in pure cultivation. As a result, these treatments can be suggested for use. Intercropping systems, as a kind of sustainable production, can make better use of available resources. The experiment was carried out as a factorial experiment in a randomized complete block design with three replications at the Faculty of Agriculture's research farm in Tabriz. The experimental treatments consisted of a two-level cropping pattern (pure safflower and 100:50 additive intercropping (safflower to fenugreek)) and a six-level fertilizer treatment. (control, 100% urea recommended by soil test, foliar application of NPK, Barvar 2 phosphate + 100% urea, Barvar 2 phosphate + 50% urea, Barvar 2 phosphate + NPK). The application of 100% urea was more effective than the other treatments in increasing the grain and oil yield of safflower under pure cultivation conditions; therefore, the highest grain yield (332.6 g m-2) and oil yield (85.18 g m-2) were obtained from pure cultivation of this plant in conjunction with the application of 100% urea. However, the treatment of applying 50% urea along with Barvar 2 phosphate demonstrated the best efficiency in grain yield and oil yield under safflower and fenugreek intercropping conditions.The 100% urea application treatment had the highest land equivalency ratio (2.1), while the NPK foliar application treatment had the lowest index (1.5). According to the study's findings, the most effective nutritional treatments for boosting safflower's grain and oil yields were 50% urea + Barvar 2 phosphate in intercropping and 100% urea in pure cultivation. As a result, these treatments can be suggested for use.