Inheritance and transgressive variability of the number of grains per ear in F1 – F2 soft spring wheat

Abstract

The research was conducted in the experimental field of Bila Tserkva NAU with reciprocal F1 – F2 hybrids obtained from crossing modern soft spring wheat varieties of different genealogical origin: Elehiia Myronivska, Simkoda Myronivska, Struna Myronivska, Kollektyvna 3, Heroinya, Leguan, Azhurnaia. The standard variety was Elehiia Myronivska. The research program included the study of the nature of inheritance in F1 of the number of grains in the main spike and the establishment of the degree and frequency of transgressions in F2 in order to identify valuable breeding material for this trait. According to the trait "number of grains per ear", we identified hybrid combinations with high performance: Struna Myronivska/Simkoda Myronivska (52.7 pcs.) and Struna Myronivska/Elehiia Myronivska (51.8 pcs.). It was found that the inheritance of the number of grains in the ear in the studied hybrids was of the type of positive superdominance, the degree of dominance in direct crosses was in the range from +1, 9 in the hybrid combination Struna Myronivska/Heroinya to +87.0 in Struna Myronivska/Leguan, and in reciprocal crosses it ranged from +3.4 in Simkoda Myronivska/Struna Myronivska to +62.3 in Leguan/Struna Myronivska. The smallest range of variability in the number of grains in the ear is characterized by the hybrid combination Struna Myronovska/Azhurnaia (15 pcs.) with a variance index of 27.1. Indicators of coefficients of variation characterize F1 as an active formative process on the basis of the trait "number of grains in the ear". In F2 transgressive forms were identified in the combinations of crosses Heroinya/Struna Myronivska, Struna Myronivska/Elehiia Mironovska and Kollektyvna 3/Struna Myronivska, the degree of transgression of which was 51.4, 45.6 and 39.4 % at a frequency of 68.1, 38.6 and 14.4 %, respectively. It has been proved that the results of transgressive variability can increase the diversity of the soft spring wheat gene pool and provide valuable selection material. Key words: spring wheat, number of grains of the main ear, inheritance, variability, transgressions, adaptability, productivity.