Homeostasis in terms of grain number from soft winter wheat plants in 2021-2023

The results of evaluating the homeostatic stability of winter wheat varieties by the number of grains per plant during 2021–2023 are presented. Twelve varieties belonging to three ecotypes — Forest-Steppe, Steppe, and Western European — were studied. It was established that the highest mean grain number per plant (89.5 and 88.0 grains, respectively) and greater homeostatic stability indices were demonstrated by the varieties Fidelius (Western European ecotype) (Hom = 1015) and Zorepad Bilotserkivskyi (Forest-Steppe ecotype) (Hom = 828). Considerable variability of the trait was revealed depending on genotype and year conditions, which is confirmed by variance analysis. The data obtained allow the identification of the most adaptive varieties for further use in breeding programmes aimed at increased productivity. Homeostatic ability (Hom) was calculated according to V. V. Khangildyn and M. A. Lytvynenko (1981): Hom = x² / S, where: Hom – homeostatic ability; x² – the mean value of the studied trait squared; S – standard deviation.