Gene mutations in rye causing embryo lethality in hybrids with wheat: allelism and chromosomal localisation

Abstract

In crosses between hexaploid wheat and inbred lines of rye, a small number of rye genotypes produce seeds carrying undifferentiated, non-viable embryos. Hybrids between such lines and those not showing this phenotype were used as pollen donors in crosses with bread wheat in order to determine the genetic basis of disturbed embryo development. A single gene, designated Eml-R1b, is causing this character. Molecular markers associated with F2 genotypes derived from a contrasting rye inbred progeny were used for a linkage study. Recombinant inbred lines of an F5 population served as testers. Eml-R1b maps to chromosome arm 6RL, along with two co-segregating microsatellite loci, Xgwm1103 and Xgwm732. Complementary interactions of deleterious genes in wheat and rye are discussed.

Keywords

• genetic mapping
• genomic interaction
• incompatibility
• post-zygotic isolation
• secale cereale
• triticum aestivum