Productivity of winter rape depends on the morphostructure of plants in the conditions of the Steppe of Ukraine

The aim of the study was to determine the morpho-structural indicators of the productive organs of winter rapeseed that influence yield, and to establish, on this basis, a strategic direction for the development of a promising assortment for cultivation in the conditions of the Southern Steppe of Ukraine. Using the hybrids Dario, Oriolus, and Blackstone (produced by VNS), a comparative analysis was conducted of the morpho-structure of vegetative and generative plant organs and their influence on yield. It was noted that the seed purity used in the study was 100.0%, and laboratory germination ranged from 91.6% to 94.0%. The total number of shoots at harvest time was largely determined by the biological properties of the hybrid and varied within the range of 9.8 to 15.3 shoots per plant. It was substantiated that the productivity of the crops was primarily determined by the number of pods on first-order branching shoots, which accounted for 75.7-78.5% of the total number of pods, depending on the biological characteristics of the hybrids. The number of pods located on the shoots of zero and secondorder branching was minimal, amounting to 12.8% and 9.5%, respectively. The average weight of 1,000 seeds showed no significant difference among the studied hybrids, ranging between 3.69 and 3.81 grams. Differences in yield among the hybrids were determined by a combination of productivity indicators, particularly the total number of pods per plant and the number of seeds per pod. The highest number of pods was observed in the Dario hybrid – 249.4 pods per plant, and the lowest in the Blackstone hybrid – 198.8 pods per plant. The Dario hybrid demonstrated the most optimal plant morpho-structure, contributing not only to the highest yield (4.89 t/ha) but also to the greatest realisation of the hybrid’s biogenetic potential (69.9%). Lower comparative indicators were observed in the Blackstone hybrid, with yield and biogenetic potential realisation at 3.11 t/ha (56.6%), respectively