Morphoagronomic characterization of ornamental sunflower progenies from open-pollination

The ornamental sunflower has stood out in the national market for flowers and ornamental plants. The species widely cultivated for grain production is also exploited as a cut flower, but on a smaller scale. The cultivation of sunflower as a cut flower is due to its beauty and its agronomic characteristics such as wide adaptation to different climates and photoperiod and the possibility of cultivation throughout the year. With the expansion of ornamental sunflower cultivation, there is a need for improvement programs aimed at selecting cultivars with the characteristics required by the ornamental sector. In this sense, the aim of this study was to characterize morphoagronomically four open-pollinated progenies of ornamental sunflower. The four progenies (A2, A4, A5, and A8) were cultivated in beds with a spacing of 25 x 25 cm, and 12 plants per progeny were evaluated. These progenies were obtained from open pollination between plants of the 'Anão de Jardim' cultivar. The characteristics evaluated were: plant height, total fresh mass, fresh stem mass 50 cm long, stem diameter at 10 cm from the head, the diameter of the closed head, and diameter of the open head. The data obtained were submitted to descriptive analysis, obtaining the mean, variance, standard deviation, and coefficient of variation. The evaluated progenies showed high variability, plant height ranged from 61.90 to 125.38 cm, for stem diameter the mean values ranged from 11.62 to 13.99 mm. The A8 and A5 progenies had values of open chapter diameter of 12.99 and 14.99 cm, respectively, meeting the standards for ornamental sunflower. The other progenies had a diameter less than 10 cm. The evaluated sunflower cultivars showed high variability, which could be explored in an ornamental sunflower genetic improvement program.