Inheritance of ‘plant height’ in F1–F2 grain sorghum combinations obtained between parental fоrms distant in ecological and geographical origin

In the grain sorghum breeding programs, much attention is paid to the trait ‘plant height’. New varieties and hybrids of this crop must be technologically advanced and, above all, meet the requirements for mechanized cultivation according to plant height. In this regard, the purpose of the current research was to establish the patterns of inheritance of ‘plant height’ in grain sorghum hybrid combinations of the first and second generation obtained between samples that were of distant ecological and geographical origin. In order to develop new breeding material adapted to mechanized cultivation, in the hybridization scheme of 2020 there were included varieties ‘Luchistoye’ and ‘Ataman’ of the FSBSI “ARC “Donskoy”, adapted to local conditions, as well as the Ugandan varieties ‘Seso 1’ and ‘Narosorg 1’. The study was carried out on the experimental plots of the FSBSI “ARC “Donskoy” in 2020–2022. The trait ‘plant height’ was estimated at the stage of full plant maturity. To analyze the inheritance of the trait in F 1 hybrids, there have been estimated dominance degrees, true and hypothetical heterosis values. Hybridological analysis of plant height in F 2 hybrids was conducted using Polygen A segregation model search program. In grain sorghum hybrid combinations of the first generation, obtained between ecologically and geographically distant parental forms, there was an overdominance of the trait ‘plant height’ (hp = 7.8–61.0), as well as the manifestation of true (24.2–37.1 %) and hypothetical (25.3–39.8 %) heterosis. The analysis of second-generation hybrids made it possible to establish differences between parental forms in two pairs of genes, which allowed in most cases to combine them with genes of other quantitative traits.