Role of rye chromosomes in the genetic control of equational division of univalents in wheat-rye di-monosomics

Division and segregation of univalent chromosomes in the course of meiosis was studied in the wheat-rye dimonosomics 1R-1A, 1R-1D, 2R-2D, 2R-2W, 5R-5A, 5R-5D, 6R-6A, 6R-W, and 7R-W (Triticum aestivum L., cultivar Saratovskaya 29-Secale cereale L., cultivar Onokhoiskaya). The di-monosomics showed significant differences in the frequency of equational division of univalents at meiotic anaphase 1. In di-monosomics with rye chromosomes 5R, 6R, 7R, the univalents mainly divided in the equational manner; the presence of 2R favored the reductional type of division. Di-monosomics in 1R showed the equational-reductional type of division. On the basis of these results, it was concluded that Edu genes controlling equational division of univalents at meiotic AI, were located on several nonhomologous rye chromosomes. P(Edu) genes, which define the high level of the equational division of univalents, are located on rye chromosomes 5R, 6R, and 7R.