Formation of New Original Material Based on the Genetic Heterogeneity of the Disomic Offspring of Aneuploid Wheat Plants

Abstract

A series of disomic lines of spring wheat Opal developed on the basis of monosomic lines of this cultivar has been studied. The lines have been tested for combining ability, and the heterosis effect has been studied in disomic lines of F1 hybrids obtained by topcrossing. The line have been demonstrated to differ both from one another and from cultivar Opal in the expression of quantitative traits, combining ability, and the degree of heterosis in F1. These data suggest that recombinations accompanying the formation of the monosomic series have changed their genetic program. To test this suggestion, intramolecular heterogeneity of 42-chromosome plants has been analyzed using polymerase chain reaction (PCR) and isoenzyme analysis. The results confirmed the differences at the DNA and protein levels. According to the results of molecular analyses, A-genome lines are the most polymorphic. Strong heterosis effects have been detected in hybrid combinations contributed by D- and B-genome lines, which are characterized by medium and low degrees of molecular genetic polymorphism. Lines that are promising in terms of breeding programs have been identified.