Breeding value based on the length of the main ear of soft winter wheat varieties in 2021-2023.

The results of a comparative analysis of the breeding value of winter wheat varieties of different ecotypes (forest-steppe, steppe, and Western European) based on main spike length during 2021–2023 are presented. It was established that the greatest mean spike length was formed by the Western European ecotype varieties Acratos (10.5 cm) and Actor (10.0 cm). Analysis of the breeding value index (Sc) allowed for the identification of varieties with the most stable parameters within their respective groups: Moulan in the Western European ecotype and Zorepad Bilotserkivskyi in the forest-steppe ecotype. The data obtained may be applied in breeding programs for the development of new source material of soft winter wheat. Breeding value (Sc) was calculated according to V. V. Khangildyn and M. A. Lytvynenko (1981): Sc = X × (Xlim / Xopt), where: Sc – breeding value; X – the mean value of the studied trait; Xlim – the minimum value of the trait; Xopt – the maximum value of the trait.