Performance inheritance and combining ability of spring barley accessions

Abstract

Purpose and objectives. To establish the gene interaction types in the performance inheritance, to evaluate the combining abilities and effects of genes for this trait in spring barley accessions.

Materials and methods. We investigated 75 F₁ spring barley hybrid combinations derived from crossing 25 female forms with three male ones (chaffy and naked). Crossing was conducted in accordance with topcross design. F₁ seeds and parents were sown with a cassette breeding planter SKS-6A. Grain pea was the forecrop. The plot area was 0.20 m². The interrow distance was 0.20 m; the inter-plot tracks were of 0.50 m. Crossings were performed in two replications. Plants were harvested manually, with roots.

For structural analysis, 20 typical plants were chosen from each F₁ hybrid population, and the performance inheritance was determined by dominance degree (h_p). The obtained data were grouped and gene interaction types were determined as per G.M. Beil and R.E. Atkins’s classification. Using two-factor analysis of variance in STATISTICA 10, we found significant differences between the GCA and SCA variances for the performance and evaluated the combining ability effects.

Results and discussion. In 2019–2020, the features of 22 spring barley cultivars and three lines were described in terms of the gene interaction types in the performance inheritance and combining ability. On this basis, the prospects of biotype selections were evaluated. In the arid conditions of 2019, F₁ only showed positive over dominance, while in favorable 2020 the inheritance types varied from positive to negative overdominance. In the two years, the general combining ability was high in female cultivars Khors and Troian. The male components did not show consistently high GCA for the both years. Hybrids between accessions with a high GCA and accessions with a lower or intermediate GCA may be promising in breeding due appearance of positive transgressions in the offspring. In 2019, the SCA effects were significantly strong in female forms Troian, Datcha, Gladys, Grace, Gatunok, Modern, and Herkules and in male forms Ahrarii and Scrabble.

Conclusions. The study found that the gene interaction types in the spring barley performance inheritance depended on cross combinations and growing conditions. In unfavorable 2019, F₁ only showed positive overdominance (heterosis), while in favorable 2020, positive overdominance, positive dominance and intermediate inheritance were observed. In 2019–2020, the high GCA was seen in female cultivars Khors and Troian. The strong SCA effects were noticed in female components Troian, Datcha, Gladys, Grace, Gatunok, Modern, and Herkules and male forms Agrarii and Scrabble. The hybrid combinations with the maximum probability of producing transgressive segregants have been selected