In the dissertation, a theoretical analysis of the current state of heterosis selection of soft winter wheat in Ukraine and the world is carried out, scientific approaches to the selection of parental components are generalized, as well as the breeding value of collection samples as parental components for the creation of highly productive heterosis hybrids based on a comprehensive assessment of morpho-biological traits, anther extrusion intensity and combinability in the conditions of the Right-Bank Forest-Steppe of Ukraine is substantiated.
Modern hybridization systems and technologies for obtaining hybrid wheat seeds, including cytoplasmic male sterility (CMS), chemical castration (CHA) and alternative systems, are analyzed.
The describes the soil and climatic conditions of the research site. The research material is presented – 92 collection samples of soft winter wheat of various ecological and geographical origin. The research scheme is described, which included a preliminary assessment of the collection, the selection of 11 promising samples, the formation of a maternal and paternal pool on their basis and the creation of experimental hybrid combinations F1 by the topcross method. Methods of field and laboratory research, including the VAEX method for assessing the anthers extrusion, phytopathological assessment, determination of elements of the crop structure and grain quality, as well as methods of mathematical and statistical analysis (correlation, regression, cluster, dispersion, analysis of combinational ability) are described.
Рresents the results of the analysis of selection and valuable traits of 92 collection samples. Significant variability in the intensity of another extrusion (from 3 to 9 points) is established. Samples with the maximum and stable manifestation of this trait are allocated. A detailed morphobiological analysis of 11 selected genotypes was carried out, which made it possible to differentiate them by plant height, heading time, resistance to diseases, elements of the crop structure and grain quality. According to the totality of traits, the studied genotypes are divided into three groups, each of which has a clearly defined selection profile, which lays the foundation for the formation of parental pools. Using correlation-regression analysis, statistically significant inverse relationships between the intensity of anther extrusion and the length of the ear, the number of spikelets and grains in the ear were revealed, which indicates a morpho-physiological compensation between the ability to cross-pollination and the elements of ear productivity.
Рresents the results of the assessment of the manifestation of heterosis and combinational ability in 25 experimental F1 hybrids. Significant variability in the manifestation of true heterosis depending on the combination of crossing was established. The highest values of true heterosis in terms of yield were recorded in the combinations Metelitsa Kharkivska/Mescal (71.7 %), Zoreslava/Mescal (66.2 %), Taira/Mescal (54.6 %) and Soborna/Mescal (49.5 %), which identifies the Mescal variety as a valuable component for increasing productivity.
The general (GCC) and specific (SCS) combinability of the parental components were assessed. Mescal (+1.47), Metelitsa Kharkivska (+1.11) and Zoreslava (+0.91) have high yield values. Altigo and Urbanus were identified as donors of high-quality grain. In terms of resistance to diseases, the highest effects of GCS were shown by Soborna and Kyivska 17 (septoria), Mescal, Yubileyna Patona and Altigo (powdery mildew).
The manifestation of competitive heterosis is investigated and a comprehensive description of promising hybrid combinations is provided. The highest competitive heterosis in terms of yield was provided by hybrids Zoreslava/Mescal (+29.8 %, 12.4 t/ha) and Metelitsa Kharkivska/Mescal (+28.4 %, 12.3 t/ha). Hybrids with pronounced specialized properties have been identified: Taira/Mescal (high resistance to powdery mildew), Soborna/Mescal (exceptional resistance to septoria), Altigo/Urbanus (high content of protein and gluten), Zoreslava/Yubileyna Patona and Taira/Urbanus (high weight of 1000 grains). Based on a comprehensive assessment, a scientifically grounded model of the use of parental components in heterosis selection has been formed. The maternal pool includes undersized, early-ripening forms with high extrusion of anthers (Altigo, Zoreslava, Metelitsa Kharkivska, Soborna, Taira). The male pool includes tall forms with later flowering and high yield structure (Achim, Mescal, Urbanus, Kyivska 17, Lirika Bilotserkivska, Yubileyna Patona).
