Search

The present study evaluated and screened high quality dumpling flour using the analytical equipment, mixolab. The corresponding result aimed to provide theoretical support for high efficient dumpling flour blending. Totally, 30 commercial dumpling flour on shelf in the market were collected for measurement of physicochemical parameters such as flour whiteness, wet gluten content, rheological properties and gelatinization properties, besides sensory evaluation for dumpling-making. Divergence of dumpling-making characteristics were analyzed and the flour were graded through cluster analysis. Additionally, a target index cross section (TICS) for high quality dump-making flour was constructed through the standard curve of Chopin+ test protocol which was the built-in function software in Mixolab. The TICS was applied for dumpling-making flour blending using Zhengmai136, Zhengmai366 and Xinmai26 as the basic flour. Results showed that, the coefficient variation of dumpling-making associated quality traits were ranked: Formation time>stability time>farinogram quality number>weakening degree>gluten index>breakdown>final viscosity>peak viscosity>wet gluten content>gelinization temperature>water absorption>whiteness>peak time>sensory score. The thirty flour collected were classified into three groups at the Euclidean distance 5.0. The second group which including 16 samples was recognized as the elite quality dumpling-making flour due to the superior index in stability time, peak viscosity, final viscosity and sensory score. The water absorption of the elite flour was 8~9 in TICS, while the mixed index ranged 5~7, gluten+index ranged 5~6, viscosity index ranged 5~7, amylase index was 7~8, and retrograded index was 7~8. Taking the flour from wheat cultivars, Zhengmai 136, Zhengmai 366 and Xinmai 26 as the basic flour, 10 mixed flour were prepared in various proportion. The mixed flour with the ration of 7:2:1, 6:3:1, 6:2:2, 5:4:1 were accordance with the elite quality RICS of the above mentioned six parameters. Results obtained from the present study would provide theoretical basis and technical support for enterprises to produce high-quality dumpling flour and flour quality control.

Abstract Background Numerous studies have shown that gluten aggregation properties directly affect the processing quality of wheat, however, the genetic basis of gluten aggregation properties were rarely reported. Results To explore the genetic basis of gluten aggregation properties in wheat, an association population consisted with 207 wheat genotypes were constructed for evaluating nine parameters of aggregation properties on GlutoPeak across three-year planting seasons. A total of 940 significant SNPs were detected for 9 GlutoPeak parameters through genome-wide association analysis (GWAS). Finally, these SNPs were integrated to 68 non-redundant QTL distributed on 20 chromosomes and 54 QTL was assigned as pleiotropic loci which accounting for multiple parameters of gluten aggregation property. Furthermore, the peak SNPs representing 54 QTL domonstrated additive effect on all the traits. There was a significant positive correlation between the number of favorable alleles and the phenotypic values of each parameter. Peak SNPs of two novel QTL, q3AL.2 and q4DL, which contributing to both PMT (peak maximum time) and A3 (area from the first minimum to torque 15 s before the maximum torque) parameters, were selected for KASP (Kompetitive Allele Specific PCR) markers development and the KASP markers can be used for effectively evaluating the quality of gluten aggregation properties in the association population. Conclusion The rapid and efficient GlutoPeak method for gluten measurement can be used for early selection of wheat breeding. This study revealed the genetic loci related to GlutoPeak parameters in association population, which would be helpful to develop wheat elite lines with improved gluten aggregation through molecular marker-assisted breeding.

Abstract Background Hexaploid wheat (Triticum aestivum L.) is a leading cereal crop worldwide. Understanding the mechanism of calcium (Ca) accumulation in wheat is important to reduce the risk of human micronutrient deficiencies. However, the mechanisms of Ca accumulation in wheat grain are only partly understood. Results Here, a genome-wide association study (GWAS) was performed to dissect the genetic basis of Ca accumulation in wheat grain using an association population consisting of 207 varieties, with phenotypic data from three locations. In total, 11 non-redundant genetic loci associated with Ca concentration were identified and they explained, on average, 9.61–26.93% of the phenotypic variation. Cultivars containing more superior alleles had increased grain Ca concentrations. Notably, four non-redundant loci were mutually verified by different statistical models in at least two environments, indicating their stability across different environments. Four putative candidate genes linked to Ca accumulation were revealed from the stable genetic loci. Among them, two genes, associated with the stable genetic loci on chromosomes 4A (AX-108912427) and 3B (AX-110922471), encode the subunits of V-type Proton ATPase (TraesCS4A02G428900 and TraesCS3B02G241000), which annotated as the typical generators of a proton gradient that might be involved in Ca homeostasis in wheat grain. Conclusion To identify genetic loci associated with Ca accumulation, we conducted GWAS on Ca concentrations and detected 11 genetic loci; whereas four genetic loci were stable across different environments. A genetic loci hot spot exists at the end of chromosome 4A and associated with the putative candidate gene TraesCS4A02G428900. The candidate gene TraesCS4A02G428900 encodes V-type proton ATPase subunit e and highly expressed in wheat grains, and it possibly involved in Ca accumulation. This study increases our understanding of the genetic architecture of Ca accumulation in wheat grains, which is potentially helpful for wheat Ca biofortification pyramid breeding.

Introduction: Gliadins are the major components of gluten proteins with vital roles on properties of end-use wheat product and health-relate quality of wheat. However, the function and regulation mechanisms of γ-gliadin genes remain unclear. Objectives: Dissect the effect of DNA methylation in the promoter of γ-gliadin gene on its expression level and gluten strength of wheat. Methods: The prokaryotic expression and reduction–oxidation reactions were performed to identify the effect of TaGli-γ-2.1 on dough strength. Bisulfite analysis and 5-Aza-2′-deoxycytidine treatment were used to verify the regulation of TaGli-γ-2.1 expression by pTaGli-γ-2.1 methylation. The content of gluten proteins composition was measured by RP-HPLC, and the gluten strength was measured by Gluten Index and Farinograph. Results: TaGli-γ-2.1 was classified into a subgroup of γ-gliadin multigene family and was preferentially expressed in the later period of grain filling. Addition of TaGli-γ-2.1 protein fragment into strong gluten wheat flour significantly decreased the stability time. Hypermethylation of three CG loci of pTaGli-γ-2.1 conferred to lower TaGli-γ-2.1 expression. Treatment with 5-Aza-2′-deoxycytidine in seeds of strong gluten wheat varieties increased the expression levels of TaGli-γ-2.1. Furthermore, the accumulations of gliadin and γ-gliadin were significantly decreased in hypermethylated wheat varieties, corresponding with the increasing of gluten index and dough stability time. Conclusion: Epigenetic modification of pTaGli-γ-2.1 affected gluten strength by modulating the proportion of gluten proteins. Hypermethylation of pTaGli-γ-2.1 is a novel genetic resource for enhancing gluten strength in wheat quality breeding.

Abstract Background Peroxidase (POD) activity plays an important role in flour-based product quality, which is mainly associated with browning and bleaching effects of flour. Here, we performed a genome-wide association study (GWAS) on POD activity using an association population consisted with 207 wheat world-wide collected varieties. Our study also provide basis for the genetic improvement of flour color-based quality in wheat. Results Twenty quantitative trait loci (QTLs) were detected associated with POD activity, explaining 5.59–12.67% of phenotypic variation. Superior alleles were positively correlated with POD activity. In addition, two SNPs were successfully developed to KASP (Kompetitive Allele-Specific PCR) markers. Two POD genes, TraesCS2B02G615700 and TraesCS2D02G583000, were aligned near the QTLs flanking genomic regions, but only TraesCS2D02G583000 displayed significant divergent expression levels (P

Abstract Background Glutenin contents and compositions are crucial factors influencing the end-use quality of wheat. Although the composition of glutenin fractions is well known, there has been relatively little research on the genetic basis of glutenin fractions in wheat. Results To elucidate the genetic basis for the contents of glutenin and its fractions, a population comprising 196 recombinant inbred lines (RILs) was constructed from two parents, Luozhen No.1 and Zhengyumai 9987, which differ regarding their total glutenin and its fraction contents (except for the By fraction). Forty-one additive Quantitative Trait Loci (QTL) were detected in four environments over two years. These QTL explained 1.3% - 53.4% of the phenotypic variation in the examined traits. Forty-three pairs of epistatic QTL (E-QTL) were detected in the RIL population across four environments. The QTL controlling the content of total glutenin and its seven fractions were detected in clusters. Seven clusters enriched with QTL for more than three traits were identified, including a QTL cluster 6AS-3, which was revealed as a novel genetic locus for glutenin and related traits. Kompetitive Allele-Specific PCR (KASP) markers developed from the main QTL cluster 1DL-2 and the previously developed KASP marker for the QTL cluster 6AS-3 were validated as significantly associated with the target traits in the RIL population and in natural varieties. Conclusions This study identified novel genetic loci related to glutenin and its seven fractions. Additionally, the developed KASP markers may be useful for the marker-assisted selection of varieties with high glutenin fraction content and for identifying individuals in the early developmental stages without the need for phenotyping mature plants. On the basis of the results of this study and the KASP markers described herein, breeders will be able to efficiently select wheat lines with favorable glutenin properties and develop elite lines with high glutenin subunit contents.

Abatract: Miniature inverted-repeat transposable elements (MITEs) are a group of DNA transposable element (TE) which preferentially distributed with gene associated regions. Tens of MITEs families have been revealed in Brassica napus genome, they scatter across the genome with tens of thousands copies and produce polymorphisms both intra- and inter-species. Our previous studies revealed a Tourist-like MITE, Monkey King, associated with vernalization requirement of B. napus, however there are still few studies reveal MITE association with agricultural traits in B. napus.In the present study, 80 polymorphic markers were developed from 55 MITEs, and used to evaluate genetic diversity in a panel of B. napus accessions consisting of 101 natural and 25 synthetic genotypes. Five agricultural traits, oil content, glucosinolate content, erucic acid content, weight of thousand seeds (WTS) and plant height, were investigated across 3-years field experiments, in addition, two traits, hypocotyl length and root length, were evaluated at the 4-leaf stage in the laboratory. Correlations between the MITE-based markers and seven traits were analyzed, finally, 10 polymorphic markers produced by 6 pairs of MITE specific primers were revealed relatively high correlation with 5 traits. Two polymorphic markers were anchored with two candidate genes, BnaA02g13530D and BnaA08g20010D, respectively, which may contribute to glucosinolate content and WTS. This research may contribute to genetic improvement through utilization of MITE-induced polymorphisms in Brassica species.

Iron (Fe) is an essential micronutrient of the body. Low concentrations of bioavailable Fe in staple food result in micronutrient malnutrition. Wheat (Triticum aestivum L.) is the most important global food crop and thus has become an important source of iron for people. Breeding nutritious wheat with high grain-Fe content has become an effective means of alleviating malnutrition. Understanding the genetic basis of micronutrient concentration in wheat grains may provide useful information for breeding for high Fe varieties through marker-assisted selection (MAS). Hence, in the present study, genome-wide association studies (GWAS) were conducted for grain Fe. An association panel of 207 accessions was genotyped using a 660K SNP array and phenotyped for grain Fe content at three locations. The genotypic and phenotypic data obtained thus were used for GWAS. A total of 911 SNPs were significantly associated with grain Fe concentrations. These SNPs were distributed on all 21 wheat chromosomes, and each SNP explained 5.79–25.31% of the phenotypic variations. Notably, the two significant SNPs (AX-108912427 and AX-94729264) not only have a more significant effect on grain Fe concentration but also have the reliability under the different environments. Furthermore, candidate genes potentially associated with grain Fe concentration were predicted, and 10 candidate genes were identified. These candidate genes were related to transport, translocation, remobilization, and accumulationof ironin wheat plants. These findings will not only help in better understanding the molecular basis of Fe accumulation in grains, but also provide elite wheat germplasms to develop Fe-rich wheat varieties through breeding.

Gliadin is a group of grain storage proteins that confers extensibility/viscosity to the dough and are vital to end-use quality in wheat. Moreover, gliadins are one of the important components for nutritional quality because they contain the nutritional unprofitable epitopes that cause chronic immune-mediated intestinal disorder in genetically susceptible individuals designated celiac disease (CD). The main genetic loci encoding the gliadins were revealed by previous studies; however, the genes related to the content of gliadins and their fractions were less elucidated. To illustrate the genetic basis of the content of gliadins and their fractions comprehensively, a recombinant inbred line (RIL) population that consisted of 196 lines was constructed from the two parents, Luozhen No.1 and Zhengyumai 9987. Quantitative trait loci (QTL) controlling the content of total gliadins and their fractions (ω-, α-, and γ-gliadin) were screened genome-widely under four environments across 2 years. Totally, thirty QTL which explained 1.97–12.83% of the phenotypic variation were detected to be distributed on 17 chromosomes and they were gathered into 12 clusters. One hundred and one pairs of epistatic QTL (E-QTL) were revealed, among which five were involved with the total gliadins and its fractions content QTL located on chromosome 1AS, 1DS, 4DS, 1DL, and 6AS. Three Kompetitive Allele-Specific PCR (KASP) markers were developed from three major QTL clusters located on chromosomes 6A, 6D, and 7D, respectively. The present research not only dissects the genetic loci for improving the content of gliadins and their three fractions, but may also contribute to marker-assisted selection of varieties with appropriate gliadin fractions content for end-use quality and health benefit at the early developmental stages and early breeding generations.

Resistant starch (RS) is a special group of starches which are slowly degraded and rarely digested in the gastrointestinal tract. It was recognized as a new type of dietary fiber that improved cardiovascular, cerebrovascular, and intestinal health. Breeding high-RS-content wheat is one of the most efficient and convenient approaches for providing an adequate amount of RS for a healthy diet. However, studies which aim to genetically illustrate RS content in wheat are still rare. In the present study, a panel of 207 wheat varieties were collected world-wide and planted under three locations. The RS content of each variety was measured, and 14 additive genetic loci were found to stably exist under more than two environments. Meanwhile, four genes were recognized as the putative candidates with annotated functions of β-amylase, α-1,4 glucan phosphorylase, sucrose transporter, and NAC domain protein. A kompetitive allele-specific PCR (KASP) marker was developed from the SNP AX-94546744, representing the genetic locus of β-amylase located. The AX-94546744-T allele can significantly increase the RS content compared to the AX-94546744-C allele. The genetic loci and KASP marker associated with RS content may be useful for wheat germplasm cultivation and variety breeding with a high RS content, further helping to improve the nutritional quality in wheat.

Bread wheat is one of the most important crops worldwide, supplying approximately one-fifth of the daily protein and the calories for human consumption. Gluten aggregation properties play important roles in determining the processing quality of wheat (Triticum aestivum L.) products. Nevertheless, the genetic basis of gluten aggregation properties has not been reported so far. In this study, a recombinant inbred line (RIL) population derived from the cross between Luozhen No. 1 and Zhengyumai 9987 was used to identify quantitative trait loci (QTL) underlying gluten aggregation properties with GlutoPeak parameters. A linkage map was constructed based on 8,518 SNPs genotyped by specific length amplified fragment sequencing (SLAF-seq). A total of 33 additive QTLs on 14 chromosomes were detected by genome-wide composite interval mapping (GCIM), four of which accounted for more than 10% of the phenotypic variation across three environments. Two major QTL clusters were identified on chromosomes 1DS and 1DL. A premature termination of codon (PTC) mutation in the candidate gene (TraesCS1D02G009900) of the QTL cluster on 1DS was detected between Luozhen No. 1 and Zhengyumai 9987, which might be responsible for the difference in gluten aggregation properties between the two varieties. Subsequently, two KASP markers were designed based on SNPs in stringent linkage with the two major QTL clusters. Results of this study provide new insights into the genetic architecture of gluten aggregation properties in wheat, which are helpful for future improvement of the processing quality in wheat breeding.

Tapetal programmed cell death (PCD) is essential in pollen grain development, and cysteine proteases are ubiquitous enzymes participating in plant PCD. Although the major papain-like cysteine proteases (PLCPs) have been investigated, the exact functions of many PLCPs are still poorly understood in PCD. Here, we identified a PLCP gene, BnaC.CP20.1, which was closely related to XP_013596648.1 from Brassica oleracea. Quantitative real-time PCR analysis revealed that BnaC.CP20.1 expression was down-regulated in male-sterile lines in oilseed rape, suggesting a connection between this gene and male sterility. BnaC.CP20.1 is especially active in the tapetum and microspores in Brassica napus from the uninucleate stage until formation of mature pollen grains during anther development. On expression of BnaC.CP20.1 prior to the tetrad stage, BnA9::BnaC.CP20.1 transgenic lines in Arabidopsis thaliana showed a malesterile phenotype with shortened siliques containing fewer or no seeds by self-crossing. Scanning electron microscopy indicated that the reticulate exine was defective in aborted microspores. Callose degradation was delayed and microspores were not released from the tetrad in a timely fashion. Additionally, the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay indicated that BnaC.CP20.1 ectopic expression led to premature tapetal PCD. Transmission electron microscopy analyses further demonstrated that the pollen abortion was due to the absence of tectum connections to the bacula in the transgenic anthers. These findings suggest that timely expression of BnaC.CP20.1 is necessary for tapetal degeneration and pollen wall formation. [ABSTRACT FROM AUTHOR]

Multienzyme associations localized to specific subcellular sites are involved in several critical functions in cellular metabolism, such as plant survival and reproduction. To date, few multienzyme complexes involved in male fertility have been examined in Brassica napus. Here, we reported that in B. napus, the members of a multienzyme complex work in an interaction pattern different from that in Arabidopsis thaliana for sporopollenin biosynthesis. 7365A, a male-sterile mutant with a relatively smooth anther cuticle, was found to have a dramatic reduction in both cutin monomers and wax composition. Proteomic comparison between the mutant 7365A and wild-type 7365B showed down-regulation of three sporopollenin biosynthetic enzymes, namely BnPKSA, BnPKSB and BnTKPR; these enzymes were tightly co-expressed with BnACOS5. BnPKSA and BnPKSB showed similar expression patterns but distinct accumulation levels, suggesting that they had partially distinct functions during sporopollenin biosynthesis. In vitro and in vivo analyses demonstrated that BnPKSB directly interacted with BnPKSA and BnACOS5, but no such interactions were found in the present investigation for BnTKPR1. Interestingly, the interaction between PKSA and PKSB has not been discovered in Arabidopsis, which may indicate a new interaction representing an additional efficient regulation method in B. napus. Taken together, we propose that BnPKSA and BnPKSB may comprise a heterodimer combined with BnACOS5, constituting a sporopollenin metabolon in tapetal cells that is related to male reproductive development in B. napus. [ABSTRACT FROM AUTHOR]