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Structural chromosome variations (SCVs) are large-scale genomic variations that can be detected by fluorescence in situ hybridization (FISH). SCVs have played important roles in the genome evolution of wheat (Triticum aestivum L.), but little is known about their genetic effects. In this study, a total of 543 wheat accessions from the Chinese wheat mini-core collection and the Shanxi Province wheat collection were used for chromosome analysis using oligonucleotide probe multiplex FISH. A total of 139 SCVs including translocations, pericentric inversions, presence/absence variations (PAVs), and copy number variations (CNVs) in heterochromatin were identified at 230 loci. The distribution frequency of SCVs varied between ecological regions and between landraces and modern cultivars. Structural analysis using SCVs as markers clearly divided the landraces and modern cultivars into different groups. There are very clear instances illustrating alien introgression and wide application of foreign germplasms improved the chromosome diversity of Chinese modern wheat cultivars. A genome-wide association study (GWAS) identified 29 SCVs associated with 12 phenotypic traits, and five (RT4AS•4AL-1DS/1DL•1DS-4AL, Mg2A-3, Mr3B-10, Mr7B-13, and Mr4A-7) of them were further validated using a doubled haploid population and advanced sib-lines, implying the potential value of these SCVs. Importantly, the number of favored SCVs that were associated with agronomic trait improvement was significantly higher in modern cultivars compared to landraces, indicating positive selection in wheat breeding. This study demonstrates the significant effects of SCVs during wheat breeding and provides an efficient method of mining favored SCVs in wheat and other crops.

Genetic architecture controlling grain lutein content of common wheat was investigated through an integration of genome-wide association study (GWAS) and linkage analysis. Putative candidate genes involved in carotenoid metabolism and regulation were identified, which provide a basis for gene cloning and development of nutrient-enriched wheat varieties through molecular breeding. Lutein, known as 'the eye vitamin', is an important component of wheat nutritional and end-use quality. However, the genetic manipulation of grain lutein content (LUC) in common wheat has not previously been well studied. Here, quantitative trait loci (QTL) associated with the LUC measured by high performance liquid chromatography (HPLC) were first identified by integrating a genome-wide association study (GWAS) and linkage mapping. A Chinese wheat mini-core collection (MCC) of 262 accessions and a doubled haploid (DH) population derived from Jinchun 7 and L1219 were genotyped using the 90K SNP array. A total of 124 significant marker-trait associations (MTAs) on all 21 wheat chromosomes except for 1A, 4D, and 5B that formed 58 QTL were detected. Among them, six stable QTL were identified on chromosomes 2AL, 2DS, 3BL, 3DL, 7AL, and 7BS. Meanwhile, three of the ten QTL identified in the DH population, QLuc.5A.1 and QLuc.5A.2 on chromosome 5AL and QLuc.6A.2 on 6AS, were stable and independently explained 5.58-10.86% of the phenotypic variation. The QLuc.6A.2 region colocalized with two MTAs identified by GWAS. Moreover, 71 carotenoid metabolism-related candidate genes were identified, and the allelic effects were analyzed in the MCC panel based on the 90K array. Results revealed that the genes CYP97A3 (Chr. 6B) and CCD1 (Chr. 5A) were significantly associated with LUC. Additionally, the gene PSY3 (QLuc.5A.1) and several candidate genes involved in the methylerythritol 4-phosphate (MEP) pathways colocalized with stable QTL regions. The present study provides potential targets for future functional gene exploration and molecular breeding in common wheat.

Flag-leaf-related traits including length (FLL), width (FLW), area (FLA), thickness (FLT), and volume (FLV) of flag leaves are the most important determinants of plant architecture and yield in wheat. Understanding the genetic basis of these traits could accelerate the breeding of high yield wheat varieties. The present study used a doubled haploid (DH) population to identify quantitative trait loci (QTL) for five flag-leaf-related traits and to analyze their correlation with grain-yield-related traits. Leaf thickness at two-thirds of the leaf length from tip to collar represented the average leaf thickness as measured with freehand sections and was used to calculate the leaf volume. This approach is a new means to easily measure FLV. A total of 79 QTL controlling the five traits were detected, explaining 3.09%-14.52% of the phenotypic variation. Among them, 15 stable QTL were identified, including two major QTL for FLT, six for FLW, three for FLA, two for FLT and two for FLV. QFLL-4A, QFLW-4B, QFLA-5D.1, QFLA-7A, QFLA-7D.1, QFLT-2B, QFLT-6A, QFLV-2A and QFLV-7D are likely novel loci. In addition, flag-leaf-related traits and grain-yield-related traits were significantly correlated. Taken together, these results provide a better understanding of the genetic basis underlying flag-leaf-related traits. Also, target regions for fine mapping and marker-assisted selection were identified and these will be valuable for breeding high yielding bread wheat.

The layout of the navigable junction on the curved river was relatively difficult. The combination of the curved flow and the oblique flow would increase lateral flow velocity in the entrance area, which affected the navigable safety of the ship. There was a bend in the entrance area of the Zhaoxian Junction downstream and a large area of flood plain on the right bank of the downstream channel, which contributed to hardly meet the navigation requirements due to flow coming straight towards waterway affected by flood plain squeezed and river bend. In this paper, normality hydraulic model with 1/80 scale was employed to experimentally optimize the influence of different river regulation measures on navigable flow conditions considering the characteristics of river bend and another situation. The effective river regulation measures were proposed by moving sluice to the left, dredging flood plain on the right bank of sluice downstream and adjusting the operation mode of sluice gate. It was verified that dredging the downstream flood plain to 65 m elevation combined with the operation of left sluice can meet navigable flow conditions requirements. The research results could be used as a reference for relevant junction projects.

Hot deformation behavior of high-strength Mg-2.5Nd-0.2Zn-1.0Zr (in wt.%) alloy was investigated by the aid of tensile tests at the temperatures ranging from 200 to 400°C and strain rates varying from 0.001 to 1 s−1. The constitutive relationship of the alloy was modeled by a hyperbolic sine equation based on experimental result. A processing map of the alloy was designed by dynamic material model, which formed a domain of instability at inferior degree of deformation temperature (200-300°C) and relatively large strain rate (1-0.02 s−1). Accordingly, a domain of stability was developed implying the maximum efficiency of power dissipation as high as 46.2%, and relating a couple of optimum parameter values to deformation process, i.e., deformation temperature of 380 °C and strain rate of 0.006 s−1, respectively. Different morphological features of the fracture surface on tensile sample were revealed varying from quasi-cleavage to ductile fracture by decreasing strain rate and simultaneously increasing deformation temperature.

In this work, a composite coating composed of iron-based amorphous material and alumina mixed with 13 wt.% titanium oxide (AT13) ceramic was successfully fabricated by High Velocity Air-fuel Flame Spray (HVAF). The corrosion process of the composite coating in Sulfate-Reducing Bacteria (SRB) solution for 31 d was investigated by Electrochemical Impedance Spectroscopy (EIS). The corrosion morphologies and corrosion products were tested by X-ray photoelectron spectroscopy. The corrosion mechanism can be divided into two stages: microbial adhesion and biofilm failure. The microbial adhesion on the surface of the composite coating improved the formation of biofilm, which improved the corrosion resistance. On the other hand, the SRB metabolic process in the biofilm accelerated the formation of corrosion products, which resulted in the failure of the biofilm and thus the composite coating was re-exposed in the corrosion solution.

Laser shock peening (LSP) is a promising surface technique to improve mechanical properties. The effect of LSP on the microstructure, high-temperature mechanical properties and residual stress of the AZ31 alloy was investigated by 3D profilometer, transmission electron microscopy, x-ray diffraction, Vickers tester, respectively. The results reveal that both nano-grain layer and compressive residual stress layer were formed in the surface of AZ31 alloy after LSP treatment. The strength of AZ31 alloy is remarkably improved by LSP as the tensile temperature is below 200 °C. While LSP has no obvious effect on the mechanical properties as the tensile temperature is above 300 °C. Fractographs of as-rolled and LSPed AZ31 alloys indicate that quasi-cleavage fracture is the dominant fracture model as the tensile temperature is below 200 °C, while ductile fracture is dominant fracture model as the tensile temperature is above 300 °C. Additionally, the strengthening mechanism of the mechanical properties of the AZ31 alloy by LSP treatment was analyzed in detail.

An efficient strategy that can guide the synthesis of materials with superior mechanical properties is important for advanced material/device design. Here, we report a feasible way to enhance hardness in transition-metal monocarbides (TMCs) by optimally filling the bonding orbitals of valence electrons. We demonstrate that the intrinsic hardness of the NaCl- and WC-type TMCs maximizes at valence electron concentrations of about 9 and 10.25 electrons per cell, respectively; any deviation from such optimal values will reduce the hardness. Using the spark plasma sintering technique, a number of W1-xRexC (x = 0-0.5) have been successfully synthesized, and powder X-ray diffractions show that they adopt the hexagonal WC-type structure. Subsequent nanoindentation and Vickers hardness measurements corroborate that the newly developed W1-xRexC samples (x = 0.1-0.3) are much harder than their parent phase (i.e., WC), marking them as the hardest TMCs for practical applications. Furthermore, the hardness enhancement can be well rationalized by the balanced occupancy of bonding and antibonding states. Our findings not only elucidate the unique hardening mechanism in a large class of TMCs but also offer a guide for the design of other hard and superhard compounds such as borides and nitrides.

Grain hardness (HI) is a key trait for wheat milling and end-use quality. Puroindoline genes (PINs) are the major genes responsible for grain hardness, but other QTLs also contribute to the trait. Therefore, it is essential to identify loci associated with the HI and allelic variations of PINs in wheat. In the present study, 287 accessions from Shanxi province representing 70 years of wheat breeding were grown in one rainfed and two irrigated conditions to study grain hardness. Genome-wide association analysis (GWAS) was performed using the 15 K array, and the variability of PIN alleles was investigated. Among the accessions, hard wheat was most common. The broad-sense heritability (H(2)) among the three environments was 99.5%, suggesting HI was mainly affected by heredity. GWAS identified nine significant marker–trait associations (MTAs), including that PINs, which explained 7.03% to 17.70% of phenotypic variation. Four MTAs on chromosome 2A, 2B, 5A, and 7A were novel loci. As for diversity of PINs, a total of 11 PINs haplotypes were detected, composed of 12 allelic variations of the PIN gene. The most frequent haplotypes were Pina-D1a/Pinb-D1b (43.9%) and Pina-Dla/Pinb-D1p (18.8%), and both the frequency of Pina-D1a/Pinb-D1b and the HI value increased with breeding years were related to local dietary habits probably. A novel double deletion allele of the PINs haplotype was found in Donghei1206. These results will be useful not only in understanding of the genetics of the HI but also in breeding for improved grain texture. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11032-022-01303-x.

The effective parameters of the composite materials with Gurtin–Murdoch ((G-M) interfaces are analyzed by standard boundary element method (BEM)-based equivalent inhomogeneity technique (EIT). The ...

Improved inorganic phosphate (Pi) use efficiency in crops will be important for sustainable agriculture. Exploring molecular mechanisms that regulate Pi uptake could provide useful information for breeding wheat with improved Pi use efficiency. Here, a TaPHR3-A1 (Gene ID: TraesCS7A02G415800) ortholog of rice OsPHR3 that functions in transcriptional regulation of Pi signaling was cloned from wheat chromosome 7A. Ectopic expression of TaPHR3-A1 in Arabidopsis and rice produced enhanced vegetative growth and more seeds. Overexpression in transgenic rice led to increased biomass, grain number, and primary panicle branching by 61.23, 42.12, and 36.34% compared with the wild type. Transgenic wheat lines with down-regulation of TaPHR3-A1 exhibited retarded growth and root hair development at the seedling stage, and showed yield-related effects at the adult stage when grown in both low- and sufficient Pi conditions, indicating that TaPHR3-A1 positively regulated tolerance to low Pi. Introgression lines further confirmed the effect of TaPHR3-A1 in improving grain number. The Chinese wheat mini core collection and a recombinant inbred line analysis demonstrated that the favorable allele TaPHR3-A1-A associated with higher grain number was positively selected in breeding. A TaPHR3-A1-derived cleaved amplified polymorphic sequence marker effectively identified haplotype TaPHR3-A1-A. Our results suggested that TaPHR3-A1 was a functional regulatory factor for Pi uptake and provided useful information for marker-assisted selection for high yield in wheat.

In this paper, region reaching controller is designed for fully actuated ocean surface vessels to reach a desired target region instead of a point. There are not the requirements for both the pre-s...

Fe45Cr16Mo16C18B5 amorphous coatings were deposited on the mild steel substrate (0.45 wt.% C) by plasma spraying, and their corrosion resistance in 3.5 wt.% NaCl solution was compared with those of the substrate and 316 stainless steel. Potentiodynamic tests revealed that the as-prepared coatings had higher resistance to local corrosion than 316 stainless steel due to their wide passivation range. Electrochemical impedance spectroscopy (EIS) measurements further explained the long-term corrosion process of the coatings and indicated their excellent corrosion resistance. Based on this analysis, a schematic diagram of the corrosion mechanism of the coatings was proposed. The obtained results imply that Fe45Cr16Mo16C18B5 amorphous coatings have a promising prospect for industrial applications.

Stripe rust is an important disease in wheat, and development of genetic resistance in cultivars is an effective approach to control the disease. Wild species of wheat, such as Thinopyrum intermedium, are an excellent gene source for wheat improvement. In this study, two stripe rust-resistant wheat–Th. intermedium chromosome translocation lines, CH4131 and CH4132, were characterized by cytogenetic and pathological methods. The introgressed chromosome fragment was tagged using amplified fragment-length polymorphism-derived sequence-characterized amplified region (SCAR) markers and intron targeting markers, indicating that CH4131 and CH4132 both possess a homologous group 3 chromatin of Th. intermedium. Genomic in situ hybridization results suggested that a very small Th. intermedium chromosome segment was translocated to the terminal region of wheat 1BS for both lines, forming a configuration of T3Ai-1BS.1BL. The two translocation lines were resistant to stripe rust, and the resistance gene, temporarily designated YrCH-1BS, was likely derived from Th. intermedium. The translocated chromosome fragments have no genetic linkage drag to agronomic performance. The grain quality indexes of these two translocations were higher than local wheat varieties. Therefore, CH4131 and CH4132 could be used as potential gene sources in wheat improvement programs. The SCAR markers are useful to select stripe rust resistance from Th. intermedium.

Chlorophyll content of the flag leaf is an important trait for drought resistance in wheat under drought stress. Understanding the regulatory mechanism of flag leaf chlorophyll content could accelerate breeding for drought resistance. In this study, we constructed a recombinant inbred line (RIL) population from a cross of drought-sensitive variety DH118 and drought-resistant variety Jinmai 919, and analyzed the chlorophyll contents of flag leaves in six experimental locations/years using the Wheat90K single-nucleotide polymorphism array. A total of 29 quantitative trait loci (QTLs) controlling flag leaf chlorophyll were detected with contributions to phenotypic variation ranging from 4.67 to 23.25%. Twelve QTLs were detected under irrigated conditions and 18 were detected under dryland (drought) conditions. Most of the QTLs detected under the different water regimes were different. Four major QTLs (Qchl.saw-3B.2, Qchl.saw-5A.2, Qchl.saw-5A.3, and Qchl.saw-5B.2) were detected in the RIL population. Qchl.saw-3B.2, possibly more suitable for marker-assisted selection of genotypes adapted to irrigated conditions, was validated by a tightly linked kompetitive allele specific PCR (KASP) marker in a doubled haploid population derived from a different cross. Qchl.saw-5A.3, a novel stably expressed QTL, was detected in the dryland environments and explained up to 23.25% of the phenotypic variation, and has potential for marker-assisted breeding of genotypes adapted to dryland conditions. The stable and major QTLs identified here add valuable information for understanding the genetic mechanism underlying chlorophyll content and provide a basis for molecular marker–assisted breeding.

In this paper, the corrosion resistances of Mg-Nd binary alloys with various contents of the neodymium (Nd) element in sulfate-reducing bacteria (SRB) were studied. In the SRB medium, the results of weight loss experiments showed that the increase in the Mg12Nd phase in the alloy increased the galvanic corrosion and the corrosion rate. However, when the continuous network distribution of the second phase formed, the corrosion resistance of the alloy improved. The biofilm was formed by the adhesion of the SRB. Meanwhile, the protection from the corrosion improved due to the corrosion products, which prevent the penetration of corrosive ions. On the other hand, the products of biological metabolism accelerated the corrosion of the matrix.

Walnut oil is an excellent source of essential fatty acids. Systematic evaluation of walnut lipids has significance for the development of the nutritional and functional value of walnut. Ultra-performance liquid chromatography/Orbitrap high-resolution mass spectrometry (UHPLC-Orbitrap HRMS) was used to characterize the lipids of walnut. A total of 525 lipids were detected and triacylglycerols (TG) (18:2/18:2/18:3) and diacylglycerols (DG) (18:2/18:2) were the main glycerolipids present. Essential fatty acids, such as linoleic acid and linolenic acid, were the main DG and TG fatty acid chains. Many types of phospholipids were observed with phosphatidic acid being present in the highest concentration (5.58%). Using a combination of metabolome and transcriptome analysis, the present study mapped the main lipid metabolism pathway in walnut. These results may provide a theoretical basis for further study and specific gene targets to enable the development of walnut with increased oil content and modified fatty acid composition.

In wheat, a QTL QTrl.saw-2D.2 associated with the total root length was identified, presumably containing genes closely related to root development. A mapping population of 184 recombinant inbred lines derived from the cross SY95-71 × CH7034 was used to map QTL for seedling root characteristics in hydroponic culture (HC) and in soil-filled pot (SP) methods. Four traits, including maximum root length (MRL), root number (RN), total length (TRL), and root diameter (RD) were measured and used in QTL analyses. A total of 33 QTL for the four root traits were detected, 17 QTLs for TRL, six for RN, seven for MRL, and three for RD. Seven QTL were detected in both HC and SP methods, which explained 7-18% phenotypic variation. One QTL QTrl.saw-2D.2 detected in both HC and SP methods was also validated in another population comprised of 215 diverse lines. This QTL is a novel QTL that explained the highest phenotypic variation 18% in all QTL identified in the present study. Based on candidate gene and comparative genomics analyses, the QTL QTrl.saw-2D.2 may contain genes closely related to root development in wheat (Triticum aestivum L.). The two candidate genes were proposed to explore in future studies.

High-quality Mg-Nd-Zn-Zr magnesium alloy billets were successfully prepared by direct chill casting. The effect of casting speed on microstructure, microsegregation, and mechanical properties of the Mg-Nd-Zn-Zr alloy was systematically investigated. The results show that the as-cast microstructure is composed of equiaxed α-Mg and Mg12Nd. Optimum values of mechanical properties were obtained corresponding to the casting speed of 90 mm/min. An age hardening at 200 °C took a remarkable effect on the mechanical properties of billets. The maximum ultimate tensile strength ~ 323.4 MPa was obtained in the billet undergoing T6 heat treatment. The shapes of concentration curves of various alloying elements (e.g., Nd and Zn) in Mg-Nd-Zn-Zr, as predicted by the Gulliver–Scheil model, resemble reasonably with the shapes measured by electron probe microanalysis.

The microbial corrosion behaviour of nickel-phosphorus (Ni-P) by Desulfovibrio desulfuricans (SRB, ATCC 7757) was investigated experimentally. The colonization of SRB on Ni-P surface was observed b...

The objective of the study is to reveal the freezing tolerance mechanisms of wheat by combining the emerging single-molecule real-time (SMRT) sequencing technology PacBio Sequel and Illumina sequencing. Commercial semiwinter wheat Zhoumai 18 was exposed to -6°C for 4 h at the four-leave stage. Leaves of the control group and freezing-treated group were used to perform cDNA library construction. PacBio SMRT sequencing yielded 51,570 high-quality isoforms from leaves of control sample of Zhoumai 18, encoded by 20,366 gene loci. In total, 73,695 transcript isoforms, corresponding to 23,039 genes, were identified from the freezing-treated leaves. Compared with transcripts from the International Wheat Genome Sequencing Consortium RefSeq v1.1, 57,667 novel isoforms were discovered, which were annotated 21,672 known gene loci, as well as 3,399 novel gene loci. Transcriptome characterization including alterative spliced events, alternative polydenylation sites, transcription factors, and fusion transcripts were also analyzed. Freezing-responsive genes and signals were uncovered and proved that the ICE-ERF-COR pathway and ABA signal transduction play a vital role in the freezing response of wheat. In this study, PacBio sequencing and Illumina sequencing were applied to investigate the freezing tolerance in common wheat, and the transcriptome results provide insights into the molecular regulation mechanisms under freezing treatment.

Alleles at the Glu-1 loci play important roles in the functional properties of wheat flour. The effects of various high-molecular-weight glutenin subunit (HMW-GS) compositions on quality traits and bread-making properties were evaluated using 235 doubled haploid lines (DHs). The experiment was conducted in a split plot design with two water regimes as the main plot treatment, and DH lines as the subplot treatments. Results showed that the presence of subunit pair 5+10 at the Glu-D1 locus, either alone or in combination with others, appears to provide an improvement in quality and bread-making properties. At the Glu-A1 locus, subunit 1 produced a higher Zeleny sedimentation value (Zel) and stretch area (SA) than subunit 2* when subunits 14+15 and 5+10 were expressed at the Glu-B1 and Glu-D1 loci, and 2* had a positive effect on the maximum dough resistance (Rmax) when subunits 14+15 and 5'+12 were expressed at the Glu-B1 and Glu-D1 loci, respectively. Given subunit 1 at the Glu-A1 locus and 5'+12 at the Glu-D1 locus, the effects of Glu-B1 subunits 14+15 on the tractility (Tra), dough stability time (ST), and dough development time (DT) under the well-watered regime were significantly higher than those of Glu-B1 subunits 13+16. However, 13+16 had a positive effect on SA under the rain-fed regime when subunits 2* and 5+10 were expressed at the Glu-A1 and Glu-D1 loci, respectively. Multiple comparisons analysis revealed that the Zel and Rmax of the six subunits and eight HMW-GS compositions were stable under different water regimes. Overall, subunit compositions 1, 13+16 and 5+10 and 1, 14+15 and 5+10 had higher values for quality traits and bread-baking properties under the two water regimes. These results could play a positive guiding role in selecting and popularizing varieties suitable for production and cultivation in local areas.

Stripe rust is an important disease in wheat, and development of genetic resistance in cultivars is an effective approach to control the disease. Wild species of wheat, such as

High-quality Mg-Nd-Zn-Zr magnesium alloy billets with diameter of 200 mm were successfully prepared by direct chill (DC) casting. The results show that microstructures of the as-cast billet prepared by DC casting are mainly composed of equiaxed a-Mg and Mg12Nd eutectic compound distributing along the grain boundaries. The average grain size decreases along the radius of the billet. And the alloying elements of Nd and Zn distribute homogeneously across the large billet. The optimum process parameters for DC casting of the Mg-Nd-Zn-Zr magnesium alloy billet with diameter of 200 mm have been experimentally determined as follows: casting temperature 710 °C and casting speed 80 mm/min. Keywords: Magnesium alloy, Direct chill casting, Microstructure, Mechanical properties

A 10 Hz deuterium/hydrogen pellet injection system (PI20) was deployed for plasma fueling of the Experimental Advanced Superconducting Tokamak (EAST). The pellet injection system requires high vacuum, system state monitoring, remote control, logical sequence of control stages, precise temperature control, safety interlocks, and data publishing. Owing to the requirements of system safety and operational reliability, a Supervisory Control and Data Acquisition (SCADA) system was developed and integrated to provide the functions of pellet injection process control, pellet video capture, vacuum devices control, and data acquisition. In this control system having two-layer architecture, an Omron Programmable Logic Controller (PLC) is used as the lower controller to control the process of pellet fabrication, cutting, acceleration, and relevant vacuum devices. An IPC(Industrial Personal Computer)is used as an upper computer with a LabView runtime environment that enables video capture and data archiving in conjunction with an operator interface (OPI) to monitor and control the status of the lower controller. The control system was successfully applied to the EAST campaign. In this paper, we describe the framework, development details, and experimental results of the control system.