Influence of growth stimulants on the elements of sunflower hybrids productivity in the conditions of the Southern Steppe of Ukraine

Abstract

Yaroslav Hadzalo, Rayisa Vozhehova, Yaroslav Likar, Tetiana Marchenko*, Oksana Tonkha

This study investigates the impact of plant growth stimulants on the yield performance of sunflower hybrids under the agroecological conditions of the Southern Steppe of Ukraine. Field experiments were conducted to evaluate different hybrid compositions and the application of biostimulants, using standardized agronomic practices and statistical analysis. Significant genotypic responses to growth regulators were observed across the tested hybrids. The highest seed yield-3.82 t/ha-was achieved by the hybrid Charodiy following treatment with the biopreparation Vympel. The application of STIMPO and Vympel led to yield increases ranging from 7.9% to 37.2% compared to the untreated control. Variance analysis revealed that hybrid composition accounted for 68.2% of yield variability, while growth stimulants contributed 20.5%. These results emphasize the synergistic potential of genotype selection and biostimulant application for optimizing sunflower productivity under steppe conditions.