Segregation Distortion Through Female Gametophytes in Interspecific Hybrids of Tetraploid Wheat as Revealed by RAPD Analysis

摘要

Interspecific crosses were made among five tetraploid wheat species including three endemic species in Transcaucasia to study chromosome marker segregation. A reciprocal cross between Triticum turgidum and T. tirnopheevi produced sterile F1s, while three reciprocal F1s obtained from cross combinations of T. durum/T. persicurn, T. durum/T. paleocolchicum and T. turgidum/T. puleocolchicum were fertile and produced euploid F2 progeny after self fertilization. Twenty RAPD markers were is nuclear markers specific to one or two species by determining the genotypes of the three fertile reciprocal F1s, and six were assigned to individual chromosomes using the D genome chromosome substitution lines. Segregation analysis in the F2s showed that five among the 20 nuclear markers were almost completely or preferentially transmitted from single parents. A complete transmission through the female gametes of one T. durum marker on chromosome 3A was shown by the analysis of BC1 progeny from the cross combination of T. durum/T. persicum. This complete segregation distortion through the female gametes was correlated with markedly reduced selfed seed set in the F1s. Preferential transmission of a T. puleocolchicum marker associated with the cytoplasm was also detected in a cross of T. paleocolchicurn x T. turgidum.