Generation of amphidiploids from hybrids of wheat and related species from the genera Aegilops, Secale, Thinopyrum, and Triticum as a source of genetic variation for wheat improvement

Abstract

We aim to improve diversity of domesticated wheat by transferring genetic variation for important target traits from related wild and cultivated grass species. The present study describes the development of F1 hybrids between wheat and related species from the genera Aegilops, Secale, Thinopyrum, and Triticum and production of new amphidiploids. Amphidiploid lines were produced from 20 different distant relatives. Both colchicine and caffeine were successfully used to double the chromosome numbers. The genomic constitution of the newly formed amphidiploids derived from seven distant relatives was determined using genomic in situ hybridization (GISH). Altogether, 42 different plants were analysed, 19 using multicolour GISH separating the chromosomes from the A, B, and D genomes of wheat, as well as the distant relative, and 23 using single colour GISH. Restructuring of the allopolyploid genome, both chromosome losses and aneuploidy, was detected in all the genomes contained by the amphidiploids. From the observed chromosome numbers there is an indication that in amphidiploids the B genome of wheat suffers chromosome losses less frequently than the other wheat genomes. Phenotyping to realize the full potential of the wheat-related grass germplasm is underway, linking the analyzed genotypes to agronomically important target traits.

Transfer of a starch phenotype from wild wheat to bread wheat by deletion of a locus controlling B-type starch granule content

“…Herein, we have described the deletion of a locus, Bgc-1 in bread wheat ( T. aestivum ), whose existence and location in the genome were inferred from work on wild wheat ( Aegilops spp.). Similar approaches include the direct introgression of genes/traits from wild species to bread wheat, as in Nemeth et al (2015) , and the identification of genes common to both types of wheat by positional cloning of the wild wheat gene, as in Yan et al (2003) . The Paragon deletion mutant population was also used previously to identify the Ph1 locus in bread wheat ( Al-Kaff et al , 2008 ).…”

Development of Stable Homozygous Wheat/Amblyopyrum muticum (Aegilops mutica) Introgression Lines and Their Cytogenetic and Molecular Characterization

“…After 14–21 days embryos were excised and cultured. Colchicine treatment was carried out as described in Nemeth et al (2015).…”

Past and Future Use of Wild Relatives in Crop Breeding

“…1). Rice (Oryza sativa L.), tomato (Solanum lycopersicum L.), and wheat in particular have sizable and well established prebreeding programs that focus specifically on CWR, leveraging advanced genomic tools and diverse characterization and evaluation data (Hajjar and Hodgkin, 2007;Kilian et al, 2011;Nemeth et al, 2015). ] have yet to benefit from largescale investment in prebreeding programs and are therefore in the earlier stages of developing varieties using CWR.…”