Molecular cytogenetic analysis of wheat – Elymus repens introgression lines with resistance to Fusarium head blight

Abstract

Elymus repens (L.) Gould (2n = 6x = 42, StStStStHH) is a hexaploid perennial wheatgrass species from the tribe Triticeae, distantly related to bread wheat Triticum aestivum L. (2n = 6x = 42, AABBDD). As a potential source of resistance to Fusarium head blight (FHB), E. repens was crossed to common wheat to transfer resistance genes. The progeny were advanced to homozygosity by single seed descent. A total of eight BC(1)F(9) progeny lines were selected and characterized in this study. The chromosome numbers of these derived lines ranged from 42 to 56, including lines with 44, 52, and 54 chromosomes. All of the lines were cytologically stable in terms of meiotic chromosome behavior. The univalent frequency in the lines varied between 0.34 and 2.36 per cell. Similarly, the multivalent frequency did not exceed 1% in any of the lines. GISH analysis revealed that the number of intact wheat chromosomes in the various lines varied between 40 and 44. Numerous translocated chromosomes were detected in all lines. The translocations involved chromosomal segments from wheat, and the St and H genomes of E. repens. Furthermore, trigenomic translocated chromosomes were detected in some of the lines. The introgression into wheat chromosomes included not only terminal types but also interstitial segments. The Fusarium head blight resistance of the eight lines, following point inoculation, varied from 5.65% infected florets to 11.46% compared with the check cultivars T. aestivum 'Roblin' and T. aestivum 'Crocus' at 100% and 85%, respectively.

A novel assembly of Thinopyrum ponticum genes into the durum wheat genome: pyramiding Fusarium head blight resistance onto recombinant lines previously engineered for other beneficial traits from the same alien species

“…Among them, species belonging to the Thinopyrum, Roegneria, Leymus and Elymus genera were mainly targeted (e.g. Wan et al 1997;Jauhar and Peterson 1998;Chen and Liu 2000;Cai et al 2005;Chen et al 2005;Oliver et al 2005;McArthur et al 2012;Turner et al 2013;Zeng et al 2013). Despite the observed occurrence of spontaneous translocations or recombination events in a number of hybrid combinations between wheat and perennial Triticeae species (e.g.…”

“…Despite the observed occurrence of spontaneous translocations or recombination events in a number of hybrid combinations between wheat and perennial Triticeae species (e.g. Jauhar and Peterson 2001;Fedak and Han 2005;Zeng et al 2013), deployment of such species, whose genomes share only partial homology (i.e. homoeology) with those of cultivated wheats, usually requires the recourse to cytogenetic strategies enabling ''chromosome engineering'' of the alien donor and the wheat recipient chromosome(s).…”

Emerging Methods for Biological Control of Barley Diseases Including the Role of Endophytes

“…Some studies isolated endophytes from related taxonomic groups of a crop species and tested the eff ect in the crop (Maciá-Vicente et al , 2008 ). CWRs are valuable resources in crop breeding programmes and have been used to transfer disease resistance (Zeng et al , 2013 ;Brar and Hucl, 2017 ;Fedak et al , 2017 ). Likewise, CWRs can be a unique source of potential biocontrol agents (Maciá-Vicente et al 2008 ;Murphy et al 2015b ).…”

Microsatellite analysis of chromosomes from the fifth homoeologous group in the introgressive Triticum aestivum/Amblyopyrum muticum wheat lines

“…The gene pool of today's common wheat cultivars contains many resistance genes against unfriendly environmental factors, whose origin is associated with the introgression of chromatin from wild relatives of common wheat [1], and the latter's genes continue to be attracted to the process of the wheat gene pool enrichment [2][3][4][5]. One of the diploid relatives of wheat that has been so far uninvolved in introgressive hybridization is the annual wild species Amblyopyrum muticum (Boiss.)…”