Summary Flour colour, kernel hardness, grain protein content and wet gluten content are important quality properties that determine end use in bread wheat. Here, a wheat 90K genotyping assay was used for a genome‐wide association study (GWAS) of the six quality‐related traits in Chinese wheat cultivars in eight environments over four years. A total of 846 significant single nucleotide polymorphisms (SNPs) were identified, explaining approximately 30% of the phenotypic variation on average, and 103 multienvironment‐significant SNPs were detected in more than four environments. Quantitative trait loci (QTL) mapping in the biparent population confirmed some important SNP loci. Moreover, it was determined that some important genes were associated with the six quality traits, including some known functional genes and annotated unknown functional genes. Of the annotated unknown functional genes, it was verified that TaRPP13L1 was associated with flour colour. Wheat cultivars or lines with TaRPP13L1‐B1a showed extremely significantly higher flour redness and lower yellowness than those with TaRPP13L1‐B1b in the Chinese wheat natural population and the doubled haploid (DH) population. Two tetraploid wheat lines with premature stop codons of the TaRPP13L1 gene mutagenized by ethyl methanesulfonate (EMS) showed extremely significantly higher flour redness and lower yellowness than wild type. Our data suggest that the TaRPP13L1 gene plays an important role in modulating wheat flour colour. This study provides useful information for further dissection of the genetic basis of flour colour and also provides valuable genes or genetic loci for marker‐assisted selection to improve the process of breeding quality wheat in China.

Protein ubiquitination, which is a major post-translational modifications that occurs in eukaryotic cells, is involved in diverse biological processes. To date, large-scale profiling of the ubiquitome in common wheat has not been reported, despite its status as the major cereal crop in the world. Here, we performed the first ubiquitome analysis of the common wheat (Triticum aestivum L.) variety, Aikang 58. Overall, 433 lysine modification sites were identified in 285 proteins in wheat seedlings, and four putative ubiquitination motifs were revealed. In particular, 83 of the 285 ubiquitinated proteins had ubiquitination orthologs in Oryza sativa L., and Arabidopsis thaliana. Ubiquitylated lysines were found to have a significantly different preference for secondary structures when compared with the all lysines. In accordance with previous studies, proteins related to binding and catalytic activity were predicted to be the preferential targets of lysine ubiquitination. Besides, protein interaction network analysis reveals that diverse interactions are modulated by protein ubiquitination. Bioinformatics analysis revealed that the ubiquitinated proteins were involved in diverse biological processes. Our data provides a global view of the ubiquitome in common wheat for the first time and lays a foundation for exploring the physiological role of lysine ubiquitination in wheat and other plants.

BackgroundThe extensive adaptability of polyploidy wheat is attributed to its complex genome, and accurately controlling heading stage is a prime target in wheat breeding process. Wheat heading stage is an essential growth and development processes since it starts at a crucial point in the transition from vegetative phase to reproductive phase.Main bodyHeading stage is mainly decided by vernalization, photoperiod, hormone (like gibberellic acid, GA), and earliness per se (Eps). As a polyploidy species, common wheat possesses the abundant genetic variation, such as allelic variation, copy number variation etc., which have a strong effect on regulation of wheat growth and development. Therefore, understanding genetic manipulation of heading stage is pivotal for controlling the heading stage in wheat. In this review, we summarized the recent advances in the genetic regulatory mechanisms and abundant variation in genetic diversity controlling heading stage in wheat, as well as the interaction mechanism of different signals and the contribution of different genetic variation. We first summarized the genes involved in vernalization, photoperoid and other signals cross-talk with each other to control wheat heading stage, then the abundant genetic variation related to signal components associated with wheat heading stage was also elaborated in detail.ConclusionOur knowledge of the regulatory network of wheat heading can be used to adjust the duration of the growth phase for the purpose of acclimatizing to different geographical environments.Electronic supplementary materialThe online version of this article (10.1186/s12870-018-1591-z) contains supplementary material, which is available to authorized users.

SummaryTo investigate the population structure and genetic diversity of Henan indigenous pig breeds, samples from a total of 78 pigs of 11 breeds were collected, including four pig populations from Henan Province, three Western commercial breeds, three Chinese native pig breeds from other provinces and one Asian wild boar. The genotyping datasets were obtained by genotyping‐by‐sequencing technology. We found a high degree of polymorphism and rapid linkage disequilibrium decay in Henan pigs. A neighbor‐joining tree, principal component analysis and structure analysis revealed that the Huainan and Erhualian pigs were clustered together and that the Queshan black pigs were clearly grouped together but that the Nanyang and Yuxi pigs were extensively admixed with Western pigs. In addition, heterozygosity values might indicate that Henan indigenous pigs, especially the Queshan black and Huainan pigs, were subjected to little selection during domestication. The results presented here indicate that Henan pig breeds were admixed from Western breeds, especially Nanyang and Yuxi pigs. Therefore, establishment of purification and rejuvenation systems to implement conservation strategies is urgent. In addition, it is also necessary to accelerate genetic resources improvement and utilization using modern breeding technologies, such as genomic selection and genome‐wide association studies.

Black point is a common disease in wheat all over the world. The disease could downgrade wheat quality and cause human health problems. In this study, 406 wheat cultivars were used to investigate black point resistance. In the field tests, 20, 65.5, and 14.5% of the tested cultivars were resistant, moderately resistant, and susceptible, respectively, suggesting that improving black point resistance is necessary in Chinese wheat breeding. A genome-wide association study (GWAS) identified 386 single-nucleotide polymorphisms (SNPs) significantly related to black point resistance in the tested wheat cultivars, and they were located on all chromosomes. Linkage mapping in a biparental population identified three quantitative trait loci (QTL) for black point resistance—QBP.hau-3A, QBP.hau-6D, and QBP.hau-7D—with 6.76, 7.79, and 8.84% phenotypic variation explained, respectively. Based on both the GWAS and linkage analyses, QBP.hau-6D covered six significant SNPs from the GWAS, and the position of these SNPs indicated that this QTL is a new locus for black point resistance. This study provides valuable germplasm for breeding wheat cultivars with resistance to black point and information for further understanding of molecular and genetic basis of black point resistance.