Heterosis level and dominance degree of economic characters in F1 tobacco hybrids

Abstract

Aims. To determine the heterosis effect and the dominance degree of economic characters in F1 tobaco hybrids in comparison with parental forms. Methods. Intraspecific hybridization, self pollination and selection. Field (phenological observations and biometric measurements), laboratory (structural analysis of breeding material, yield accounting), mathematical and statistical (dispersion analysis, calculation effect of true heterosis and the degree of phenotypic dominance). Results. On the basis of the obtained experimental data, heterosis effect and the types of character inheritance of F1 tobacco hybrids by productivity elements were determined. A high level of heterosis and inheritance by the type of positive overdominance was observed in 62.5% according to plant height; 87.5% according to the number of leaves; 62.5% according to the leaf surface area and 75.0% according to the yield of tobacco raw materials. Conclusions. According to the investigated characters, the best hybrid combinations were selected: by plant height – Hostrolyst Yuvileinyi × Berley 38 (Htrue = 29.2%, Hp = 3.3), Berley 46 × Ternopilskyi 14 (Htrue = 18.0%, Hp = 2.0); by the number of leaves – Berley 46 × Virginia 27 ( Htrue = 8.7%, Hp = 1.8), Hostrolyst Rubin × Berley 46 (Htrue = 8.7%, Hp = 1.8); by leaf surface area – Berley 46 × Ternopilskyi 14 (Htrue = 25.6%, Hp = 7.6), Hostrolist Yuvileinyi × Ternopilskyi 14 (Htrue = 21.7%, Hp = 3.1), Ternopilskyi 14 × Berley 46 (Htrue = 11.6%, Hp = 4.0); by the yield of tobacco raw materials – Berley 46 × Ternopilskyi 14 (Htrue = 26.9%, Hp = 8.0), Berley 46 × Virginia 27 (Htrue = 18.5%, Hp = 4.3). The created highly heterosis combinations and combinations with high coefficients of character inheritance are promising for their further use in the selection process.