Inheritance of resistance of spring barley to Erysiphe graminis f. sp. hordei in F1 and variability in F2 in the conditions of the Right-Bank Forest-Steppe of Ukraine

Abstract

The nature of the inheritance of resistance to Erysiphe graminis f. sp. hordei in the crosses of genotypes of spring barley in F1 and transgressive variability in F2 populations are investigated. Inheritance of the trait of resistance to Erysiphe graminis f. sp. hordei in F1, by hybridization of genotypes of spring barley with known genes of resistance to Erysiphe graminis f. sp. hordei in European varieties Eunova (mlo11) and Barke (mlo9), which are located on chromosome 1H, was positively dominated. Inheritance of the F1 trait in Aspen (mlo11) and Adonis (mlo9) cultivars was partially positive. The influence of parental pairs for hybridization on the indicators of the degree of phenotypic dominance, hypothetical and true heterosis was established. Resistance to Erysiphe graminis f. sp. hordei in F1 hybrids was observed heterosis (positive dominance) in fve hybrid combinations (hp = 1.1–1.9 %): Barke/Badoryi, Barke/Sanktrum, Parnas/Rostentsii, Badoryi/ Barke, Eunova/Zvershennia. Hypothetical heterosis (Ht) in F1 was observed in 13 of 16 hybrids (from +2.8 % to +97.6 %). A positive value of true heterosis (Htb) in F1 was observed in 15 hybrids out of 16 (from +1.9 % to +98.8 %). Inheritance of the trait of resistance to Erysiphe graminis f. sp. hordei in all studied hybrids was influenced by the cytoplasm of the mother plant, except for the hybrid Eunova / Triangel, where the influence of the nuclear apparatus was detected. Hybrids were found in the F 2 population with high resistance to Erysiphe graminis f. sp. hordei, which exceeded the parental components, which indicates a signifcant shaping process and the possibility of selection on the basis of the studied trait. The degree of positive transgression ranged from 16.0 % to 73.0 % in hybrids Aspen / Skarlet, Adonis / Vanja, Barke / Badoryi, Barke / Sanktrum, Eunova / Triangel and Eunova / Zvershennia, where highly resistant varieties were used for the mother form. The combinations in which the frequency of transgression was observed in more than 50.0 % of plants are hybrids: Eunova / Triangel, Barke / Sanktrum, Eunova / Zvershennia, Parnas / Rostentsii and Barke / Badoryi. Key words: spring barley, resistance, Erysiphe graminis f. sp. hordei, combinations of crossing, inheritance, F1, true and hypothetical heterosis, degree of phenotypic dominance, F 2, degree and frequency of transgressions.