Abstract. The selection of primary material when creating and introducing into the production of new highly productive bread wheat varieties in the rainfed lands of the Republic is the main factor. At the same time, the assessment of lines created by the hybridization method in terms of the length of the growing season and productivity and the best lines and their transfer to the next stages of breeding is the most important task facing breeders, this article refers to the selection work carried out to determine the productivity indicators of new lines.