Homeostasis in terms of grain weight of the main ear of soft winter wheat varieties in 2021-2023.

Here is the scientific English translation: The results of evaluating the homeostatic stability of winter wheat varieties of different ecotypes (forest-steppe, steppe, and Western European) based on the grain mass per main spike are presented for the period 2021–2023. A higher level of homeostatic stability (Hom = 106) and minimal trait variability (S² = 0.002) were established in the Western European ecotype variety Fidelius. Among the forest-steppe ecotype varieties, a higher homeostatic index was recorded in Zoреpad Bilotserkivskyi (Hom = 24), whereas the steppe ecotype variety Lisova Pisnia was characterized by lower adaptive capacity to environmental conditions. The data obtained allow for the identification of the most stress-tolerant genotypes for application in breeding programs aimed at improving 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.