Abstract: The cut sunflower （Helianthus annuus L.） variety Paladin was used as the experimental material, and 80 mg/L polybulobulozole, 200 mg/L macrobutenol, 100 mg/L acetanilide, 20 mg/L enlobulobulozole and 800 mg/L butohydrazide were applied on the leaf surface with water as the control. After reaching harvest maturity, stem, leaf and flower characters of the cut sunflower were measured under different treatment conditions. The results showed that, compared with CK, each treatment reduced plant height, center of gravity, leaf area and petiole length to varying degrees, and increased stem ratio, leaf thickness, chlorophyll content and flower-to-total mass ratio. The flower plate diameter and stem diameter of 80 mg/L polybulobuzole treatment increased by 13.4% and 37.4%, and the flower plate diameter and stem diameter of 20 mg/L enlobuzole treatment increased by 7.3% and 17.3%, which improved the quality of cut flowers. Plant growth retarder could reduce plant height, decrease center of gravity, increase stem ratio, shorten petiole, shrink and thicken leaves, increase chlorophyll content and improve cut flower quality, among which the comprehensive effects of polybulobuzole and tenbulobuzole treatment were better.

Key words: cut sunflower（Helianthus annuus L.）, plant growth retarder, agronomic characters