Development and identification of new syntheticT. turgidum–T. monococcumamphiploids

Abstract

Triticum monococcum ssp. monococcum has useful traits for bread wheat improvement. The synthesis of Triticum turgidum–T. monococcum amphiploids is an essential step for transferring genes from T. monococcum into bread wheat. In this study, 264 wide hybridization combinations were done by crossing 60 T. turgidum lines belonging to five subspecies with 83 T. monococcum accessions. Without embryo rescue and hormone treatment, from the 10,810 florets pollinated, 1983 seeds were obtained, with a mean crossability of 18.34% (range 0–89.29%). Many hybrid seeds (90.73%, 923/1017) could germinate and produce plants. A total of 56 new amphiploids (AABBAmAm) were produced by colchicine treatment of T. turgidum × T. monococcum F1 hybrids. The chromosome constitution of amphiploids was characterized by fluorescence in situ hybridization using oligonucleotides probes with different chromosome and sub-chromosome specificities. Sodium dodecyl sulphate polyacrylamide gel electrophoresis analysis indicated that the Glu-A1m-b, Glu-A1m-c, Glu-A1m-d and Glu-A1m-h proteins of T. monococcum were expressed in some amphiploids. Despite resistance reduction in several cases, 45 out of 56 amphiploids exhibited resistance to the current predominant Chinese stripe rust races at both the seedling and adult plant stage. These novel amphiploids provide new germplasm for the potential improvement of bread wheat quality and stripe rust resistance.

Molecular cytogenetic identification of a new synthetic amphiploid (Triticum timococcum, AtAtGGAmAm) with a seed setting rate comparable with that of natural Triticum zhukovskyi

“…monococcum accessions expressed two HMW glutenin subunits (Figure 5). Based on earlier research, the Glu‐A1 m x subunits were 1Ax2.1 b for PI 418582 and 1Ax2.1 d for PI 573524 (Li et al, 2016, 2018). Only two subunits were expressed in the tetraploid PI 119442 and were also expressed in the T .…”

“…FISH is a valid method for distinguishing the A and G genomes of T . timopheevii and the A m genome of cultivated einkorn (Badaeva et al, 2016; Li et al, 2018; Liu et al, 2018; Mikó et al, 2015). In this research, the chromosome constitutions of the newly synthesized T .…”

“…Evaluation of hybridization signals and acquisition of photographic images was consistent with the methods of Liu et al (2018). The identification of A t and G genome chromosomes depended on Mikó et al (2015) and Liu et al (2018), and identification of A m genome chromosomes followed Megyeri et al (2012) and Li et al (2018).…”

Improvement and Re-Evolution of Tetraploid Wheat for Global Environmental Challenge and Diversity Consumption Demand

“…They could be used to transfer alien genes into durum wheat through inter-ploidy hybridization. Moreover, desirable genes or traits can also be introduced into durum wheat via 'bridge-crossing' using synthesized amphiploids, for instances AASS, AABBA m A m , and AABBSS [168,170,[210][211][212][213].…”

Exploring the diversity of promoter and 5′UTR sequences in ancestral, historic and modern wheat

“…The distribution of the selected genes across the Chinese Spring (CS) chromosomes (IWGSC_refseq_v1.0) are shown in Figure S1. For the germplasm to be analysed, 69 historic and modern commercial hexaploid wheat (Triticum aestivum) cultivars including CS, 15 wheat landraces (T. aestivum) from the A. E. Watkins collection (Winfield et al, 2018;Wingen et al, 2014), eight T. monococcum (2n = 2x = 14; A m A m ) accessions (Jing et al, 2007;Li et al, 2018;McMillan et al, 2014;Simons et al, 2021) and single accessions for T. durum (2n = 4x = 28; AABB), Aegilops tauschii (2n = 2x = 14; DD), Ae. speltoides (ASP) (2n = 2x = 14; SS) and the wild species Ae.…”