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Pre-harvest sprouting (PHS) induced by the absence of seed dormancy causes a severe reduction in crop yield and flour quality. In this study, we isolated and characterized TaABI4, an ABA-responsive transcription factor that participates in regulating seed germination in wheat. Sequence analysis revealed that TaABI4 has three homologues, located on chromosomes 1A/1B/1D. TaABI4 contains a conserved AP2 domain, and AP2-associated, LRP and potential PEST motifs. Putative cis-acting regulatory elements (CE1-like box, W-box, ABRE elements and RY elements) were identified in the TaABI4 promoter region that showed high conservation in 17 wheat cultivars and wheat-related species. Expression profiling of TaABI4 indicated that it is a seed-specific gene accumulating during the middle stages of seed development. Transcript accumulation of TaABI4 in wheat cultivar Chuanmai 32 (CM32, PHS susceptible) was 5.07-fold and 1.39-fold higher than that in synthetic hexaploidy wheat SHW-L1 (PHS resistant) at 15 and 20 DPA, respectively. Six expression quantitative trait loci (eQTL) of TaABI4 on chromosomes 2A, 2D, 3B and 4A were characterized based on the accumulated transcripts of TaABI4 in SHW-L1 and CM32-derived recombinant inbred lines. These QTLs explained 10.7 to 46.1% of the trait variation with 4.53–10.59 of LOD scores, which contain genes that may affect the expression of TaABI4.

The PLATZ (plant AT-rich protein and zinc-binding protein) transcription factor family is a class of plant-specific zinc-dependent DNA-binding proteins. PLATZ has essential roles in seed endosperm development, as well as promoting cell proliferation duration in the earlier stages of the crops. In the present study, 62 TaPLATZ genes were identified from the wheat genome, and they were unequally distributed on 15 chromosomes. According to the phylogenetic analysis, 62 TaPLATZ genes were classified into six groups, including two groups that were unique in wheat. Members in the same groups shared similar exon-intron structures. The polyploidization, together with genome duplication of wheat, plays a crucial role in the expansion of the TaPLATZs family. Transcriptome data indicated a distinct divergence expression pattern of TaPLATZ genes that could be clustered into four modules. The TaPLATZs in Module b possessed a seed-specific expression pattern and displayed obvious high expression in the earlier development stage of seeds. Subcellular localization data of TaPLATZs suggesting that they likely perform a function as a conventional transcription factor. This study provides insight into understanding the structure divergence, evolutionary features, expression profiles, and potential function of PLATZ in wheat.

Map-based cloning of plant disease resistance (R) genes is time-consuming. Here, we reported the isolation of blast R gene Pid4 using comparative transcriptomic profiling and genome-wide sequence analysis. Pid4 encodes a coiled-coil nucleotide-binding site leucine-rich repeat (CC-NBS-LRR) protein and is constitutively expressed at diverse developmental stages in the rice variety Digu. The Pid4 protein is localized in both the nucleus and cytoplasm. Introduction of Pid4 into susceptible rice cultivars confers race-specific resistance to leaf and neck blast. Amino acid sequence comparison and blast resistance spectrum tests showed that Pid4 is a novel R gene, different from the previously reported R genes located in the same gene cluster. A Pid4 Indel marker was developed to facilitate the identification of Pid4 in different rice varieties. We demonstrated that a plant R gene can be quickly isolated using transcriptomic profiling coupled with genome-wide sequence analysis.

Summary Wheat was introduced to China approximately 4500 years ago, where it adapted over a span of time to various environments in agro‐ecological growing zones. We investigated 717 Chinese and 14 Iranian/Turkish geographically diverse, locally adapted wheat landraces with 27 933 DArTseq (for 717 landraces) and 312 831 Wheat660K (for a subset of 285 landraces) markers. This study highlights the adaptive evolutionary history of wheat cultivation in China. Environmental stresses and independent selection efforts have resulted in considerable genome‐wide divergence at the population level in Chinese wheat landraces. In total, 148 regions of the wheat genome show signs of selection in at least one geographic area. Our data show adaptive events across geographic areas, from the xeric northwest to the mesic south, along and among homoeologous chromosomes, with fewer variations in the D genome than in the A and B genomes. Multiple variations in interdependent functional genes such as regulatory and metabolic genes controlling germination and flowering time were characterized, showing clear allelic frequency changes corresponding to the dispersion of wheat in China. Population structure and selection data reveal that Chinese wheat spread from the northwestern Caspian Sea region to South China, adapting during its agricultural trajectory to increasingly mesic and warm climatic areas.

Pre-harvest sprouting (PHS) causes serious damage that leads to deterioration in overall quality and decreased yield and reduction of grain yield in cereal. In this study, two major quantitative trait loci (QTLs), qPHS.sicau-3D and qPHS.sicau-1B, were detected in synthetic wheat (SHW-L1) and were derived from Aegilops tauschii AS60 (deep dormant) and Triticum turgidum AS2255 (medium PHS-resistant). qPHS.sicau-1B is located in the region near the telomere of 1BS, and qPHS.sicau-3D is located on the end of 3DL; these QTLs explain approximately 20.99% and 42.47% of the phenotypic variation. Pyramiding of both QTLs showed superior PHS resistance in recombinant inbred lines (RILs). The array-based SNP markers AX-94924265 for qPHS.sicau-1B and AX-94415259 for qPHS.sicau-3D were successfully converted to Kompetitive Allele Specific Polymerase Chain Reaction (KASP) and STS markers. L10-1580 is a light red breeding materials selected from SHW-L1-derived breeding lines that harbors the PHS-tolerant elite alleles which showed similar germination level with SHW-L1 and better resistance than other common wheat parents. L10-1580 harbors the elite alleles AX-94924265_GG/AX-94415259_B which showed similar PHS resistance as SHW-L1 and better resistance than other common wheat parents. Therefore, these QTLs for PHS resistance obtained from synthetic wheat could combine or coexist with other elite agronomic traits in high-yield wheat cultivars.

Summary Rice feeds half the world's population, and rice blast is often a destructive disease that results in significant crop loss. Non-race-specific resistance has been more effective in controlling crop diseases than race-specific resistance because of its broad spectrum and durability. Through a genome-wide association study, we report the identification of a natural allele of a C 2 H 2 -type transcription factor in rice that confers non-race-specific resistance to blast. A survey of 3,000 sequenced rice genomes reveals that this allele exists in 10% of rice, suggesting that this favorable trait has been selected through breeding. This allele causes a single nucleotide change in the promoter of the bsr-d1 gene, which results in reduced expression of the gene through the binding of the repressive MYB transcription factor and, consequently, an inhibition of H 2 O 2 degradation and enhanced disease resistance. Our discovery highlights this novel allele as a strategy for breeding durable resistance in rice.