Development of consistently crossable wheat genotypes for alien wheat gene transfer through fine-mapping of the Kr1 locus

• Published in: Theoretical and applied genetics Vol. 119; no. 8; pp. 1371 - 1381
• Main Authors: Bertin, Isabelle, Fish, Lesley, Foote, Tracie N, Knight, Emilie, Snape, John, Moore, Graham
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.11.2009; Springer-Verlag; Springer; Springer Nature B.V; Springer Verlag
• Subjects: Agriculture; Biochemistry; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Chromosome Mapping; Chromosomes; Chromosomes, Plant; Classical genetics, quantitative genetics, hybrids; Cloning; Crosses, Genetic; Expressed Sequence Tags; Fundamental and applied biological sciences. Psychology; Gene Transfer Techniques; Genes; Genes, Plant; Genetic diversity; Genetic Markers; Genetics; Genetics of eukaryotes. Biological and molecular evolution; Genomics; Genotype; Germplasm; Life Sciences; Methods, theories and miscellaneous; Original Paper; Plant Biochemistry; Plant Breeding/Biotechnology; Plant Genetics and Genomics; Pteridophyta, spermatophyta; Recombination, Genetic; Research parks; Triticum - genetics; Triticum aestivum; Vegetals; Wheat; United Kingdom; China; United Kingdom > UK; Bacterial Artificial Chromosome Library; Recombinant Line; Crossability Region; Brachypodium; Wheat Line; Genetic mapping; Monocotyledones; Gramineae; Angiospermae; Development; Genotype; Genetics; Spermatophyta; Agriculture; Triticum aestivum; Genetic transfer; GENETIQUE
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s00122-009-1141-z

Breeders can force sexual hybridisation between wheat and related grass species to produce interspecific hybrids containing a dihaploid set of wheat and related chromosomes. This facilitates the introgression of desirable genes into wheat from the secondary gene pool. However, most elite European wheat varieties carry genes that suppress crossability, making the transfer of novel traits from exotic germplasm into elite wheat varieties difficult or impossible. Previous studies have identified at least five crossability loci in wheat. Here, the crossability locus with the largest effect, Kr1 on chromosome arm 5BL, was fine-mapped by developing a series of recombinant substitution lines in which the genome of the normally non-crossable wheat variety ‘Hobbit sib' carries a recombinant 5BL chromosome arm containing segments from the crossable variety ‘Chinese Spring'. These recombinant lines were scored for their ability to cross with rye over four seasons. Analysis revealed at least two regions on 5BL affecting crossability, including the Kr1 locus. However, the ability to set seed is highly dependent on prevailing environmental conditions. Typically, even crossable wheat lines exhibit little or no seed set when crossed with rye in winter, but show up to 90% seed set from similar crosses made in summer. By recombining different combinations of the two regions affecting crossability, wheat lines that consistently exhibit up to 50% seed set, whether crossed in the UK winter or summer conditions, were generated, thus creating a very important tool for increasing the efficiency of alien wheat transfer programmes.