Production and Molecular Cytogenetic Characterization of a Durum Wheat-<b><i>Thinopyrum elongatum</i></b> 7E Disomic Addition Line with Resistance to Fusarium Head Blight

Abstract

Wheatgrass, Thinopyrum elongatum (2n = 2x = 14, EE), is an important wild relative of wheat with many excellent traits, including resistance to Fusarium head blight (FHB), that can be used for durum wheat improvement. Through hybridization of the durum cultivar “Langdon” with the amphiploid 8801 (AABBEE), a disomic alien addition line (2n = 30) with a pair of Th. elongatum 7E chromosomes was obtained and confirmed using chromosome-specific molecular markers of Th. elongatum and genomic in situ hybridization (GISH). This line is meiotically and reproductively stable, generally forming 15 bivalents at meiosis including 14 pairs from Langdon and 1 from Th. elongatum with 2 chiasmata each as revealed by GISH analysis. At the adult growth stages under field conditions, this addition line shows high resistance to FHB, with less than 16% infection on visual observation in 2 years (2014 and 2015). This addition line is shorter in height and has narrower leaves and shorter spikes as compared to its parent Langdon. So the linkage group 7E might be a further source of wheat improvement by targeted introgression approaches.

Equipping Durum Wheat—Thinopyrum ponticum Recombinant Lines With a Thinopyrum elongatum Major QTL for Resistance to Fusarium Diseases Through a Cytogenetic Strategy

“…This locus has been shown to confer the same protection against FHB to different bread wheat lines, from the standard CS to the Italian elite cultivar Blasco (Ceoloni et al, 2017a), and to unrelated durum wheat genotypes, such as the Italian cv. Simeto (this work) and Langdon, an old North Dakota variety and laboratory line to which the complete chromosome 7E was recently added (Liu et al, 2017). Moreover, comparing the resistance demonstrated by the latter work with the results presented here confirms that the exceptional FHB resistance associated with Th.…”

Genome mapping of quantitative trait loci (QTL) controlling domestication traits of intermediate wheatgrass (Thinopyrum intermedium)

“…Species of the genus Thinopyrum, including IWG, are considered the closest perennial relatives of common wheat (Triticum aestivum) and comprise a useful part of its tertiary gene pool (Ceoloni et al 2015;Lang et al 2018;Li et al 2017;Liu et al 2017;Uzma et al 2015;Zair et al 2018). Common wheat and IWG have similar allohexaploid genomes (2n=6x=42).…”

Identification of 5P Chromosomes in Wheat-Agropyron cristatum Addition Line and Analysis of Its Effect on Homologous Pairing of Wheat Chromosomes

“…Furthermore, they are favorable materials to identify the relationship between alien and wheat chromosomes, which could also be used for gene mapping. At present, most of the wheat wild relatives have been successfully hybridized with wheat, such as Aegilops ( Gong et al, 2017 ; Du et al, 2019 ; Liu et al, 2019 ; Yi et al, 2019 ), Secale cereal L. ( Li et al, 2016a , 2020 ; Schneider et al, 2016 ; An et al, 2019 ), Hordeum vulgare L. ( Szakacs and Molnal-Lang, 2010 ; Fang et al, 2014 ), Haynaldia villosa ( Zhang et al, 2015a , 2018a , b ), Leymus racemosus ( Yang et al, 2017 ; Zhang et al, 2017a ), and Elytrigia repens ( Liu et al, 2017 ). Meanwhile, a large number of disomic addition lines and substitution lines were identified, which were used to create translocation lines and introgression lines containing desirable genes.…”