Impact of agronomic traits variability on grain yield of mid-oleic and standard sunflower hybrids vs. open-pollinated populations in Iran

This study compares three types of sunflower genotypes (standard hybrids, mid-oleic hybrids, and open-pollinated populations) regarding agronomic characteristics, using 16 standard hybrids, 9 mid-oleic hybrids, and 11 openpollinated populations. the genotypes were evaluated in 6×6 simple lattice experiments conducted in karaj and shahrood, iran, during the 2020-2021 growing season. the highest grain yield (3468 kg ha⁻¹) and oil yield (1462 kg ha⁻¹) were observed in standard hybrids, while the lowest values occurred in mid-oleic hybrids. standard hybrids also exhibited the earliest maturity (96 days) and the shortest plant height (124 cm). in contrast, mid-oleic hybrids were characterized by lower grain yield (2513 kg ha⁻¹) and oil yield (1108 kg ha⁻¹) compared to the other genotypes. open-pollinated populations showed similarities to standard hybrids in terms of grain and oil yield; however, the highest yields were consistently recorded among standard hybrids. these results indicate that not all crosses yield high-yielding hybrids with enhanced oil content. whilethe uniformity of hybrid cultivars facilitates agricultural operations, the higher yield observed in some open-pollinated populations justifies their cultivation in variable and unstable climatic conditions, particularly in marginal areas. given the significant yield reduction in mid-oleic hybrids in iran, their commercial production will depend on market demand and achieving a balance between yield and oleic acid content.