North American safflower cultivars can be considered as alternatives for cultivation in light of the limited improvement in the commercially grown and registered cultivars in Brazil. This study aimed to evaluate the initial growth and agronomic performance of North American safflower cultivars in Brazil. The experimental design for North American cultivars included random blocks with six cultivars (S-351, 3307, 8311, 0260, 0210 and S-323) and six replicates. The emergence percentage, emergence

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... peed index, average emergence time, and average emergence speed were determined at 15 days after emergence (DAE). Plant height, stem diameter, number of leaves per plant, fresh plant mass, and dry plant mass were determined at 30 DAE. Plant height, stem diameter, number of branches, number of chapters, number of leaves, fresh plant mass, dry plant mass, fresh root mass, and dry root mass were determined at the flowering stage. The final plant density, number of chapters per plant, 100-grain weight, grain yield, oil content, and protein content were determined at the harvest stage. Cultivar S-351 had the greatest initial growth and exhibited greater emergence and emergence speed index. At 30 DAE, the cultivars did not differ with respect to the accumulation of dry mass and number of leaves. During flowering, cultivars S-323 and 8311 had greater accumulation of plant and root dry mass, as well as a greater number of leaves, branches, and chapters. Cultivars 210 and 260 had higher grain yield, whereas cultivars 3307 and S-323 had higher oil content, and cultivar S-351 had higher protein content.