The influence of genotype and year conditions on the transgressive variability of stem length in popu-lations of the second generation of soft winter wheat

In 2019–2020, in the conditions of experimental field Bila Tserkva National Agrarian University, populations F2 hybrids, created by crossing soft winter wheat varieties that differ duration growing season, were studied. The aim work was to establish degree and frequency transgressions length main stem depending on meteorological year parental forms selected for hybridization, select selectively valuable recombinants further research. 2019, 40 out 42 populations, only a positive transgression established terms stem, from 2.5 % (Myronivsk early/Kolchuga) 53.8 (Zolotokolosa/Shchedra nyva). With use maternal cytoplasm early ripening four all plants exceeded extreme maximum values parents, with hybridization mid-early, mid-ripening, mid-late varieties, 13 such combinations 2020, transgressive isolated six 20 based form early-ripening negative ones – nine. Negative 21 mid-maturing, varieties. At same time, no found. selection pairs differing precociousness before expands morphogenesis promotes both stem. A significant influence initial formation manifestation minimum second generation established. has greater effect variability compared medium-early, medium-maturing medium-late forms. Key words: transgressions, wheat, maturity groups, parent forms, length, populations.