ENRICHMENT OF THE GENETIC DIVERSITY OF INITIAL MATERIAL IN BREAD SPRING WHEAT BREEDING BY ATTRACTING THE WINTER WHEAT
The expansion of genetic diversity based on spring-winter and-winter-spring hybrids reveals the possibilities of obtaining genotypes most adapted to unfavorable environmental factors in the Forest- Steppe of Ukraine, which is especially important in the crop breeding. The aim of the study was to create new initial material of bread spring wheat when using crosses of samples with different growth habit. Based on the results of the study, the effectiveness of using winter forms with spring ones was established. It is determined that in the simple F<sub>1</sub> hybrids the spring growth habit is dominant. Splitting into spring and winter forms in F<sub>3</sub>-F<sub>4</sub> was observed in 3-58 % of individual selections depending on the origin. In subsequent generations, the appearance of winter forms was not observed. High productive, resistant to lodging and basic fungal diseases, with good bread- baking grain quality spring wheat lines were distinguished, which indicates the prospects of using winter forms in spring wheat breeding. The varieties (Simkoda мyronivska, MIP Zlata, Dubravka, MIP Svitlana, MIP Dana) and various source material of bread spring wheat has been created which was involved in breeding process of the spring wheat breeding laboratory of MIW which provide a broad formative process in subsequent generations.