Hybridization as a source of genetic variability in winter wheat breeding

Abstract

Purpose. Creation of basic material, sources with a set of valuable traits, and varieties of winter wheat being adapted to the conditions of the Forest-Steppe of Ukraine, when using double pollination in intraspecific hybridization. Methods. The studies were carried out in 1988–2019 on the experimental fields of breeding crop rotation of the V. M. Remeslo Myronivka Institute of Wheat of NAAS. There were created 4275 hybrid combinations using double pollination method. Results. The average hybrid seed-setting rate over the years of the research was 60.1 % with range of variation 8.1–100 %. The maximal index was noted in mid-ripening / mid-ripening crosses (in 58.1 % of cases) and the minimal one was in mid-, late ripening ↔ early ripening (61.3 % of cases). The average seed-setting rate under conditions of eight years was less than the general average (60.1 %). For four years (2002, 1991, 2019, 1998), the difference was from 5.8 % (1998) to 11.3 % (2002), while the weather conditions during hybridization period in 1991 and 2002 were favorable. Statistically significant decrease in seed-setting rate (21.5–34.3 %) was noted in unfavorable conditions in 2000, 2016, 1999, 2012. In addition, it was during these years that targeted selection of contrasting in cropping season duration components for crosses was carried out. The mid-ripening / mid-ripening group of crossing predominated in the most years. 1999, 2002 were the exceptions in which the mid-ripening ↔ early-ripening groups prevailed. The effectiveness of using the double pollination method for intraspecific hybridization is confirmed by winter wheat varieties created during the research period, namely Myrych, Myrliena, Berehynia myronіvska, Hospodynia myronіvska, MIP Vyshyvanka, MIP Kniazhna, MIP Assol, Balada myronivska, Avrora Myronivska. Conclusions. Hybrid seed-setting rate depended on weather conditions during hybridization and the convergence between flowering periods in components of crossing. The use of double pollination method made it possible to shorten winter bread wheat hybridization, to reduce time and dependence on adverse weather conditions during pollination, and thus to increase efficiency of crossings.