Investigation on the possibility to efficiently use Ukrainian cultivars for developing of early winter wheat lines

I. Grain productivity
N. Tsenov, T. Petrova, E. Tsenova
Abstract. Situation and aims. This investigation was carried out with the aim to determine the suitability of some Ukrainian wheat cultivars for improvement of the productivity of the Bulgarian ecotype of winter wheat. The economic traits and properties of promising breeding lines from crosses between them were studied. The focus was on the breeding possibilities of compromise combining early maturation with grain yield.
Methods. A total of 50 genotypes were investigated: 40 of them were lines (from 4 hybrid combinations), 8 parental lines and several standard cultivars for comparison. Data were obtained from competitive varietal trials after growing for several successive years. The main traits directly or indirectly related to productivity were analyzed. The combination of earliness with the other economic traits and indices is discussed from the point of view of the combining ability of the early parents involved in the combinations.
Key results. Although each studied combination involved an early parent, it was found that early forms were obtained with the participation of cultivars Obriy and Mironovskaya 29. The percent of early lines was highest in the combinations with their participation. In the crosses involving Albatros odeskiy and Mironovskaya 27, the productivity of the early lines was lower than the productivity of the parental lines. Cultivar Obriy was most promising for breeding work, especially for combining early heading with higher grain yield through high values of number of productive ears and grain size.
Conclusions. Cultivars Albatros odeskiy and Obriy were most suitable for obtaining higher productivity in combination with earliness. The deriving of lines with earlier date to heading and higher productivity from the early cultivars Mironovskaya 29, Galateya and Enola was completely successful. By using specific cultivars, there is the possibility to combine high yield with earliness but within the limits of the specific parental cultivars for each individual combination.