Existing data in the literature on polyteny in plants and in eukaryotes in general, data on the structure of interphase chromosomes and their association with the nuclear membrane are analyzed in the paper. In light of these data, the results of our studies on the ratios of phenotypic classes of marker enzymes in agamospermy (apomictic) progeny of sugar beet are considered. The given data allow to state that chromosome polyteny and their association with nuclear membrane provide not only hereditary information, but also determine the ratio of genotypes and phenotypes in progeny.