Özet:

This study aimed to investigate the effect of the combination of mycorrhizal fungi, vermicompost, and humic acid application on ornamental sunflower growth. The study employed ornamental sunflower (Helianthus annuus L. cv. ‘Sunsantion’) as the plant material. Seedlings, acquired from a local ornamental production company at the four-true-leaf stage, were planted in plastic pots (2 L) containing peat perlite medium (1:1 v/v). The research incorporated three distinct doses of humic acid (10, 20, and 30 ml/L) and vermicompost (10, 20, and 30 ml/L). Humic acid (HA) and vermicompost (VC) were applied by soil drenching with 200 ml solution per pot. After one week, the seedlings were transferred into the pots. In all Mycorrhizae applications, 2 g/pot mycorrhizae inoculated during seedling transferred into the pots. Additionally, 20 ml of humic acid (HA20/M2) and vermicompost (VC20/M2) were combined with mycorrhiza application and applied to the plants. No application was made to the control group. Relative growth rate (RGR) was calculated from harvested samples of individuals from the same application group at 15 and 30 days after plants were transferred into the pots. The highest RGR obtained from HA20/M2 and vermicompost VC20/M2 treatments was 3.55 and 3.48, respectively. Additionally, the highest values of flower diameter (11.71 cm), stem length (41.13 cm), stem diameter (8.46 cm), and flower longevity (10.4 days) were observed in VC20/M2 treatment.