Summary Wheat awn plays a vital role in photosynthesis, grain production, and drought tolerance. However, the systematic identification or cloning of genes controlling wheat awn development is seldom reported. Here, we conducted a genome‐wide association study (GWAS) with 364 wheat accessions and identified 26 loci involved in awn length development, including previously characterized B1, B2, Hd, and several rice homologs. The dominant awn suppressor B1 was fine mapped to a 125‐kb physical interval, and a C2H2 zinc finger protein Awn Length Inhibitor 1 (ALI‐1) was confirmed to be the underlying gene of the B1 locus through the functional complimentary test with native awnless allele. ALI‐1 expresses predominantly in the developing spike of awnless individuals, transcriptionally suppressing downstream genes. ALI‐1 reduces cytokinin content and simultaneously restrains cytokinin signal transduction, leading to a stagnation of cell proliferation and reduction of cell numbers during awn development. Polymorphisms of four single nucleotide polymorphisms (SNPs) located in ALI‐1 promoter region are diagnostic for the B1/b1 genotypes, and these SNPs are associated with awn length (AL), grain length (GL) and thousand‐grain weight (TGW). More importantly, ali‐1 was observed to increase grain length in wheat, which is a valuable attribute of awn on grain weight, aside from photosynthesis. Therefore, ALI‐1 pleiotropically regulates awn and grain development, providing an alternative for grain yield improvement and addressing future climate changes.

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The synthesis of seed storage protein (SSP) is mainly regulated at the transcriptional level. However, few transcriptional regulators of SSP synthesis have been characterized in common wheat (Triticum aestivum) owing to the complex genome. As the A genome donor of common wheat, Triticum urartu could be an elite model in wheat research considering its simple genome. Here, a novel NAC family transcription factor TuSPR from T. urartu was found preferentially expressed in developing endosperm during grain-filling stages. In common wheat transgenically overexpressing TuSPR, the content of total SSPs was reduced by c. 15.97% attributed to the transcription declines of SSP genes. Both in vitro and in vivo assays showed that TuSPR bound to the cis-element 5 0 -CANNTG-3 0 distributed in SSP gene promoters and suppressed the transcription. The homolog in common wheat TaSPR shared a conserved function with TuSPR on SSP synthesis suppression. The knock-down of TaSPR in common wheat resulted in 7.07%-20.34% increases in the total SSPs. Both TuSPR and TaSPR could be superior targets in genetic engineering to manipulate SSP content in wheat, and this work undoubtedly expands our knowledge of SSP gene regulation.

The endosperm storage protein of 46 European wheat (Triticum aestivum L.) landraces and obsolete cultivars have been fractionated by SDS-PAGE to determine the composition of high molecular weight glutenin subunits (HMW-GS) composition. It has been discovered that about 46% of the wheats were heterogeneous, comprising 2-11 different glutenin profiles. Eighteen of them were observed to be homogeneous. A total of 13 HMW-GS alleles, including 3 at the Glu-A1, 8 at the Glu-B1, and 3 at the Glu-D1 loci were revealed. HMW-GS null controlled by locus Glu-A1, subunits 7 + 8 by Glu-B1, and 2 + 12 by Glu-D1 predominated. However low frequented alleles such as 17 + 18, 20, 6, and 7 were observed. Furthermore, other new alleles encoding HMW-GS at the locus Glu-B1 have been found in one of France cultivar (Saumur d'Automne). The glutenin-based quality score ranged from 4 to 10.

In this study, a total of 299 grain samples of wheat were collected from four production regions: the maize, sugar beet, potato and feed sectors of Slovakia. The samples were analyzed for deoxynivalenol (DON) content by using an enzyme-linked immunosorbent assay Ridascreen® Fast DON. Analysis of variance revealed a significant difference between years in DON contents (p < 0.027). The occurrence of samples with DON was 82.2% in 2010, with maximum DON content of 7.88 mg kg−1, and 70.7% in 2011, with maximum DON content of 2.12 mg·kg−1. The total mean DON content was 0.62 mg·kg−1; in the feed region 0.22 mg·kg−1; 0.63 mg·kg−1 in the maize region; 0.78 mg·kg−1 in the sugar beet region; 0.45 mg·kg−1 the potato region. The limit of 1.25 mg·kg−1 imposed by the European Union (EU) for DON content was exceeded in 13.7% of the studied samples. The average monthly rainfall for May to June played a critical role in DON content of wheat grains for maize and sugar beet producing regions. The present results indicate that DON content was at a high level in grains from wheat grown during 2010.