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Background Heavy metal cadmium (Cd) is a common environmental pollutant in soils, which has an negative impacts on crop growth and development. At present, cadmium has become a major soil and water heavy metal pollutant, which not only causes permanent and irreversible health problems for humans, but also causes a significant reduction in crop yields. Results This study examined the chemical forms of Cd in the roots of two wheat varieties (M1019 and Xinong20) by continuous extraction and analyzed differences in distribution characteristics of Cd in the root cell wall, cytoplasm, and organelles by elemental content determination and subcellular separation. Furthermore, we conducted proteomics analysis of the roots of the two varieties under Cd pollution using mass spectrometry quantitative proteomics techniques. A total of 11,651 proteins were identified, of which 10,532 proteins contained quantitative information. In addition, the differentially expressed proteins in the two varieties were related to DNA replication and repair, protein metabolism, and the glutathione metabolism pathway. Conclusion The results of this study improve our understanding of the mechanism of plant responses to Cd stress.

One RIL population derived from the cross between Dalibao and BYL8 was used to examine the phenotypes of kernel-related traits in four different environments. Six important kernel traits, kernel length (KL), kernel width (KW), kernel perimeter (KP), kernel area (KA), kernel length/width ratio (KLW), and thousand-kernel weight (TKW) were evaluated in Yangling, Shaanxi Province, China (2016 and 2017), Nanyang, Henan Province, China (2017) and Suqian, Jiangsu Province, China (2017). A genetic linkage map was constructed using 205 SSR markers, and a total of 21 significant QTLs for KL, KW, KP, KA, KLW and TKW were located on 10 of the 21 wheat chromosomes, including 1A, 1B, 2A, 2B, 2D, 3D, 4D, 5A, 5B, and 7D, with a single QTL in different environments explaining 3.495–30.130% of the phenotypic variation. There were four loci for KLW, five for KA, five for KL, three for KP, two for KW, and two for TKW among the detected QTLs. We used BSA + 660 K gene chip technology to reveal the positions of major novel QTLs for KLW. A total of 670 out of 5285 polymorphic SNPs were detected on chromosome 2A. The SNPs in 2A are most likely related to the major QTL, and there may be minor QTLs on 5B, 7A, 3A and 4B. SSR markers were developed to verify the chromosome region associated with KLW. A linkage map was constructed with 7 SSR markers, and a major effect QTL was identified within a 21.55 cM interval, corresponding to a physical interval of 10.8 Mb in the Chinese Spring RefSeq v1.0 sequence. This study can provide useful information for subsequent construction of fine mapping and marker-assisted selection breeding.

The utilization of crop heterosis can greatly improve crop yield. The sterile line is vital for the heterosis utilization of wheat (Triticum aestivum L.). The chloroplast genomes of two sterile lines and one maintainer were sequenced using second-generation high-throughput technology and assembled. The nonsynonymous mutated genes among the three varieties were identified, the expressed difference was further analyzed by qPCR, and finally, the function of the differentially expressed genes was analyzed by the barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) method. A total of 16 genes containing 31 nonsynonymous mutations between K519A and 519B were identified. There were no base mutations in the protein-encoding genes between K519A and YS3038. The chloroplast genomes of 519B and K519A were closely related to the Triticum genus and Aegilops genus, respectively. The gene expression levels of the six selected genes with nonsynonymous mutation sites for K519A compared to 519B were mostly downregulated at the binucleate and trinucleate stages of pollen development. The seed setting rates of atpB-silenced or ndhH-silenced 519B plants by BSMV-VIGS method were significantly reduced. It can be concluded that atpB and the ndhH are likely to be involved in the reproductive transformation of 519B.

Heterosis can improve the stress resistance, quality, and yield of crops, and the male sterility of wheat can be utilized to accelerate the breeding process of hybrid. To determine whether mitochondrial genes are involved in the fertility of K-type cytoplasmic male-sterile (CMS) line and the YS-type thermosensitive male-sterile (TMS) line in wheat, we sequenced and assembled the mitochondrial genomes of K519A, 519B, and YS3038 by next-generation sequencing (NGS). The non-synonymous mutations were analyzed, and the first-generation sequencing was conducted to verify the non-synonymous mutation sites. Furthermore, the expression patterns of genes with non-synonymous mutations were analyzed. Finally, the candidate genes were silenced by barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) to test the functions of the candidate genes. The results revealed that the mitochondrial genomes of K519A, 519B, and YS3038 were 420,543, 433,560, and 452,567 bp in length, respectively. Besides, 33, 31, and 37 protein-coding genes were identified in K519A, 519B, and YS3038, respectively. There were 14 protein-coding genes and 83 open reading frame (ORF) sequences that differed between K519A and 519B and 10 protein-coding genes and 122 ORF sequences that differed between K519A and YS3038. At the binucleate stage, seven genes (nad6, ORF256, ORF216, ORF138, atp6, nad3, and cox1) were downregulated in K519A compared with 519B, and 10 genes (nad6, atp6, cox3, atp8, nad3, cox1, rps3, ORF216, ORF138, and ORF224) were downregulated in YS3038 compared with K519A. Besides, six genes (nad6, ORF138, cox3, cox1, rps3, and ORF224) were downregulated under fertile conditions relative to sterile conditions in YS3038. Gene silencing analysis showed that the silencing of cox1 significantly reduced the seed setting rate of YS3038, indicating that the cox1 gene may be involved in the fertility transformation of YS3038. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11032-021-01252-x.

Class III peroxidases are classical secretory plant peroxidases belonging to a large multi-gene family. Class III peroxidases are involved in various physical processes and the response to biotic and abiotic stress to protect plants from environmental adversities. In this study, 151 BdPrx genes were identified using HMM and Blastp program. According to their physical location, the 151 BdPrx genes were mapped on five chromosomes. The results of Gene Structure Display Serve and MEME revealed that BdPrxs in the same subgroup shared similar gene structure, and their protein sequences were highly conserved. Based on the analysis of evolutionary relationships and Ka/Ks, 151 BdPrx genes were divided into 15 subgroups, they have undergone purifying selection. In addition, the result of GO annotation showed that 100% of the BdPrxs participated in antioxidant. The protein-protein interaction network was constructed using the orthology-based method, found that 66 BdPrxs were involved in the regulatory network and 183 network branches were identified. Furthermore, analysis of the transcriptome data indicated that the BdPrx genes responded to low concentration of exogenous phytohormones and exhibited different levels of expression in the different tissues. Subsequently, 19 genes were selected for quantitative real-time PCR and found to be mainly expressed in the roots, might preferentially respond to hydrogen peroxide and gibberellin. Our results provide a foundation for further evolutionary and functional study of Prx genes in B. distachyon.

Background Members of the plant-specific SPL gene family (squamosa promoter-binding protein -like) contain the SBP conserved domain and are involved in the regulation of plant growth and development, including the development of plant flowers and plant epidermal hair, the plant stress response, and the synthesis of secondary metabolites. This family has been identified in various plants. However, there is no systematic analysis of the SPL gene family at the genome-wide level of wheat. Results In this study, 56 putative TaSPL genes were identified using the comparative genomics method; we renamed them TaSPL001 - TaSPL056 on their chromosomal distribution. According to the un-rooted neighbor joining phylogenetic tree, gene structure and motif analyses, the 56 TaSPL genes were divided into 8 subgroups. A total of 81 TaSPL gene pairs were designated as arising from duplication events and 64 interacting protein branches were identified as involve in the protein interaction network. The expression patterns of 21 randomly selected TaSPL genes in different tissues (roots, stems, leaves and inflorescence) and under 4 treatments (abscisic acid, gibberellin, drought and salt) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Conclusions The wheat genome contains 56 TaSPL genes and those in same subfamily share similar gene structure and motifs. TaSPL gene expansion occurred through segmental duplication events. Combining the results of transcriptional and qRT-PCR analyses, most of these TaSPL genes were found to regulate inflorescence and spike development. Additionally, we found that 13 TaSPLs were upregulated by abscisic acid, indicating that TaSPL genes play a positive role in the abscisic acid-mediated pathway of the seedling stage. This study provides comprehensive information on the SPL gene family of wheat and lays a solid foundation for elucidating the biological functions of TaSPLs and improvement of wheat yield.

Previous studies have indicated that noncoding RNAs are important factors in gene functions. To explore the mechanism of male sterility of YS3038, the sterile genes were mapped, and based on previous work, the expression of long noncoding RNAs (lncRNAs), circular RNAs (circRNAs), and their target genes was studied. Weighted gene coexpression network analysis (WGCNA) and competitive endogenous RNA (ceRNA) analysis were further performed for differentially expressed noncoding RNAs and target genes. At last, the candidate genes were silenced by barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) to prove their function. The sterile genes were mapped on chromosomes 1B and 6B based on chip mix pool analysis, and one major effect QTL (27.3190% variation) was found based on SSR primers. The WGCNA analysis revealed that the dark turquoise and steel blue modules were highly correlated with anther development and fertility conversion, respectively. The ceRNA analysis showed that a total of 184 RNAs interacted with each other, including 115 mRNAs, 55 microRNAs (miRNAs), eight circRNAs, and six lncRNAs. Finally, the seed setting rate of the plant was significantly decreased after fatty acyl-CoA reductase 5 silencing. This study provides breeders with a new option for the development of thermosensitive cytoplasmic male-sterile (TCMS) wheat lines, which will favor the sustainable development of two-line hybrid wheat.

The sterile line is vital for the heterosis utilization of wheat (Triticum aestivum L.), and the cytoplasmic male sterility (CMS) line has more practical significance in the utilization of heterosis. To reveal the sterile mechanism of wheat K-CMS line K519A from the perspective of the chloroplast genome, the chloroplast genomes of the K519A and its same nuclear genotype maintainer line 519B were sequenced using second-generation high-throughput technology and assembled. Then the chloroplast genomic contents, SSR sequences, long repeat fragments, and qPCR were analyzed. The results showed that the total length of K519A and 519B were 136,996 bp and 136,235 bp, respectively. Both chloroplast genomes encode 126 genes, including 89 protein-coding genes, 8 rRNA genes, and 39 tRNA genes. There were 186 and 188 SSRs in K519A and 519B, respectively. And a developed SSR maker, which from atpF, can be used to distinguish the cytoplasmic type of Aegilops kotschyi and Triticum aestivum, respectively. There were 50 and 52 long repeat fragments, which come from the gene sequences, in K519A and 519B, respectively. A total of 107 mutations between K519A and 519B, which from 45 genes, were identified, of which, 16 genes (matK, rps16, rpoB, rpoC2, atpI, ndhK, atpB, rbcL, psbB, psbH, rpl14, ndhH, ndhF, rpl32, ccsA, ndhA) contained non-synonymous mutations. Further, the qPCR analysis was performed, and the gene expression levels of selected six genes for K519A compared to 519B were mostly downregulated at the binucleate and trinucleate stages of pollen development, thus, these non-synonymous mutant genes might affect the fertility of K519A.

In the wheat TCMS line YS3038, the anther development is inhibited from late uninucleate stage to the binucleate stage. The disruption of energy metabolism pathways by aberrant transcriptional regulation causes the male sterility under low temperatures. The utilization of thermosensitive male sterile (TMS) lines provides a basis for two-line breeding. Previous work, including morphological and cytological observations, has shown that the development process of the TMS line YS3038 is inhibited from the late uninucleate stage to the binucleate stage. Transcriptomics studies could now help to elucidate the overall expression of related genes in a specific reproductive process, revealing the metabolic network and its regulatory mechanism of the reproductive process from the transcription level. Considering the fertility characteristics of YS3038, three important stages for transcriptome analysis were determined to be the early uninucleate, late uninucleate and binucleate stages. The number of differentially expressed genes (DEGs) was found to be highest in the binucleate stage, and most were related to energy metabolism. Quantitative PCR analysis of selected genes related to energy metabolism revealed that their expression patterns were consistent with the sequencing results. Analysis of the fertility mechanism of YS3038 showed that although the tapetum of anthers was degraded in advance of the tetrad stage, the development of microspores did not result in obvious abnormalities until the binucleate stage, because the genes involved in energy metabolism pathways, including starch and sucrose metabolism (SSM), glycolysis, the tricarboxylic acid (TCA) cycle, oxidative phosphorylation, and respiration electron transport chain are differentially expressed under sterile and fertile conditions. Therefore, the pollen in YS3038 was sterile.

The presence and morphology of plant brace roots are important root architecture traits. Brace roots contribute significantly to effective anchorage and water and nutrient uptake during late growth and development, and more importantly, have a substantial influence on grain yield under soil flooding or water limited conditions. However, little is known about the genetic mechanisms that underlie brace root traits. In this study, quantitative trait loci (QTLs) for presence of brace roots from the sorghum landrace "Sansui" were mapped and associated molecular markers were identified. A linkage map was constructed with 109 assigned simple sequence repeat markers using a F2 mapping population derived from the cross Sansui/Jiliang 2. Two QTLs associated with presence of brace roots were localized on chromosomes 6 and 7. The major QTL on chromosome 7 between markers Dsenhsbm7 and Xcup 70 explained about 52.5% of the phenotypic variation, and the minor QTL on chromosome 6 was flanked by Xtxp127 and Xtxp6 and accounted for 7.0% of phenotypic variation. These results will provide information for the improvement of sorghum root architecture associated with brace roots.

Association mapping is widely used for detecting QTLs in higher plants. In the present study a synthetic sorghum population containing 119 representative samples, including 43 sweet and 76 grain sorghum accessions originating mainly from China, USA and India, were genotyped using 51 simple-sequence repeat (SSR) markers. Linkage disequilibrium (LD) of pair-wise loci and population structure were analyzed, followed by association analysis of SSR loci and 3 sugar yield related traits using the TASSEL general linear model program. Results showed that: (i) different degrees of LD occurred among syntenic markers and also among nonsyntenic markers, indicating historical recombination among sorghum linkage groups; (ii) significant LD extended up to 7.31 cM; (iii) the collection of accessions was composed of three subgroups; (iv) four marker loci were associated with stalk sugar concentration, fresh stalk weight and stalk juice weight measured in different growing environments and could be used, therefore, in future marker assisted breeding programs. Several loci were also associated with two or more traits simultaneously, which might be due to tight linkage between different genes affecting these traits and/or pleiotropy. In addition, some associated markers were located close to QTLs previously mapped in family-based linkage mapping analyses.

The function of a member of the actin-depolymerizing factor family from Gossypium barbadense, GbADF1, was investigated. Tobacco (Nicotiana tabacum) lines expressing GbADF1 were produced by Agrobacterium-mediated transformation. Southern and northern blot analyses showed that GbADF1 was successfully incorporated as a single copy into the tobacco genome and stably expressed in three lines of T1 transgenic tobacco plants. Biological changes were detected in these transgenic lines, wherein GbADF1 transgenic seedlings exhibited shorter hypocotyls along with fewer root hairs than those of control plants. Moreover, guard cells of leaves of the transgenic plants were induced to close stomata, while flowering was delayed 5 days in T1 lines compared to those of empty vector transgenic control plants. Segregation of GbADF1 in the T2 generation fits the expected 3:1 ratio corresponding to a single dominant gene. Subsequently, GbADF1 was fused to the green fluorescent protein gene to generate a fusion expression vector. Transient expression analysis indicated that this fusion protein was localized in the nucleus and cytoskeleton of epidermal cells of onion. These results suggest that actin-depolymerizing factor 1 gene from G. barbadense plays an important role in the process of plant cell morphogenesis.

Sorghum productivity around the world is influenced by a wide array of biotic and abiotic constraints, some of which cause significant economic losses. Great efforts have been made in the past to improve plant resistance to biotic stresses such as insect pests, diseases, and parasitic weeds through breeding and genetic engineering. However, limited success has been achieved owing to the genetic complexity of stress responses. The application of marker-assisted breeding and transgenics will help to address this challenge more effectively. Genomic approaches such as high-throughput sequencing and large-scale genotyping technologies have been used in germplasm diversity analysis, genetic linkage mapping, association studies, and marker-assisted selection to improve sorghum biotic stress resistance. This chapter presents genomics-assisted methods that have helped in understanding diversity in sorghum germplasm resources and resistance against major insect pests, diseases, and parasitic weeds. Furthermore, the chapter deals with the progress in identification and deployment of gene and quantitative trait locus (QTL) for biotic stress resistance.

3,5-Dihydroxy-4-i-propylstilbene (DHPS) is a compound expected to be developed into effective drugs for many inflammatory and autoimmune diseases. In order to improve the stablity of DHPS, the cross-linked chitosan (CS) microspheres loading of DHPS were prepared and characterized. The optimal conditions for preparing CS-microspheres loading of DHPS were investigated. The results showed that the CS-microspheres loading of DHPS had spherical shape with diameters between 8 and 12 microns. The entrapment of DHPS in the CS-microspheres was more than 36%. The released percentage of CS-microspheres loading of DHPS in pH 3.6 buffer solution was up to 30.9% within 96 h. In transdermal in vitro release, DHPS kept release within 60 h through rat skin and the released percentage could arrive 76.2%. The CS-microspheres loading of DHPS had excellent stability and ability of sustained release.

The dendritic Ag nanostructure with ordered branches and a “clean” surface has been successfully prepared via a facile surfactant-free and acetone-based mixed solvents route at room temperature. Experiments and structural characterizations reveal that the dendritic Ag nanostructure is evolved from the initially generated triangular nanoplates by the reaction of AgNO3 with l-ascorbic acid to the dendrites through both the Ostwald ripening and the oriented attachment growth processes. The acetone plays the key role in controlling the nucleation, growth, conversion, and assembly of the Ag nanoparticles. In the absence of acetone, only the polyhedral particles can be obtained. The yield of the dendrites is dependent on the volume ratio of acetone to water. The present work provides an example for the synthesis of a novel metal nanostructure by simply adjusting the solvent components, which is important for the qualitative understanding of the solvent effect on the morphology of nanostructures and the controll...

Cement-based materials are brittle and low in flexural strength, which can be greatly improved by adding organic monomers to cement-based matrixes due to the polymerization effect of added the organics. The solution polymerization behaviors of organic monomer in cement paste and its effect on cement properties have been studied in this paper. The results show that the organic monomers used in the experiment can well polymerize themselves in cement pastes by solution polymerization effect under common conditions. As results, the cement composites have a flexural strength between 17.8 and 33.4 MPa, greatly dependent on the amount of organic monomers added and is stable when it is immersed in water, acid, alkali and salt solutions. Besides, the setting time of the composites can be controlled and regulated.

Yue Zhang1,2, Jungang Gao1, Hetang Zheng2, Ran Zhang3, Yucui Han21College of Chemistry and Enviromental Science, Hebei University, Baoding, China; 2School of Chemical and Pharmaceutical Engineering, Hebei University of Science and Technology, Shijiazhuang, China; 3College of Chemical Engineering, East China University of Science and Technology, Shanghai, ChinaAbstract: We have reported a novel procedure to prepare 3,5-dihydroxy-4-isopropylstilbene (DHPS) nanoemulsion, using a low-energy emulsification method. Based on the phase diagram, the optimum prescription of nanoemulsion preparation was screened. With polyoxyethylenated castor oil (EL-40) as the surfactant, ethanol as the co-surfactant, and isopropyl myristate (IPM) as the oil phase, the DHPS nanoemulsion was obtained with a transparent appearance, little viscosity, and spherically uniform distribution verified by transmission electron microscopy and laser scattering analyzer. The nanoemulsion was also determined by FT-Raman spectroscopy. The DHPS nanoemulsion demonstrated good stability and stable physical and chemical properties. The nanoemulsion dramatically improved the transdermal release of DHPS (from 8.02 µg· cm-2 to 273.15 µg· cm-2) and could become a favorable new dosage form for DHPS.Keywords: nanoemulsion, 3,5-dihydroxy-4-isopropylstilbene, DHPS, pseudo-ternary phase diagram

Sorghum is one of the most promising bioenergy crops. Stem juice yield, together with stem sugar concentration, determines sugar yield in sweet sorghum. Bulked segregant analysis (BSA) is a gene mapping technique for identifying genomic regions containing genetic loci affecting a trait of interest that when combined with deep sequencing could effectively accelerate the gene mapping process. In this study, a dry stem sorghum landrace was characterized and the stem water controlling locus, qSW6, was fine mapped using QTL analysis and the combined BSA and deep sequencing technologies. Results showed that: (i) In sorghum variety Jiliang 2, stem water content was around 80% before flowering stage. It dropped to 75% during grain filling with little difference between different internodes. In landrace G21, stem water content keeps dropping after the flag leaf stage. The drop from 71% at flowering time progressed to 60% at grain filling time. Large differences exist between different internodes with the lowest (51%) at the 7th and 8th internodes at dough stage. (ii) A quantitative trait locus (QTL) controlling stem water content mapped on chromosome 6 between SSR markers Ch6-2 and gpsb069 explained about 34.7-56.9% of the phenotypic variation for the 5th to 10th internodes, respectively. (iii) BSA and deep sequencing analysis narrowed the associated region to 339 kb containing 38 putative genes. The results could help reveal molecular mechanisms underlying juice yield of sorghum and thus to improve total sugar yield.

Background Sorghum is mainly used as a human food and beverage source, playing an important role in the production of ethanol and other bio-industrial products. Thus it is regarded as a model crop for energy plants. Genetic map construction is the foundation for marker-assisted selection and gene cloning. So far several sorghum linkage maps have been reported using different kinds of molecular markers. However marker numbers and chromosome coverage are limited. As a result, it is difficult to get consistent results and the maps are hard to unify. In the present study, the genomes of 130 individuals consisting an F2 population together with their parents were surveyed using a high-throughput sequencing technique. A high-density linkage map was constructed using specific-locus amplified fragments (SLAF) markers. This map can provide information and serve as a reference for effective gene exploration, and for marker assisted-breeding program. Results A high-throughput sequencing method was adopted to screen SLAF markers with 130 F2 individuals from a cross between a grain sorghum variety, J204, and a sweet sorghum variety, Keter. In the present study, 52,928 suitable SLAF markers out of 43,528,021 pair-end reads were chosen to conduct genetic map construction, 12.0% of which were polymorphic. Among the 6353 polymorphic SLAF markers, 5829 (91.8%) were successfully genotyped in the F2 mapping population. Finally 2246 SLAF markers were obtained to construct a high-density genetic linkage map. The total distance of linkage map covering all 10 chromosomes was 2158.1 cM. The largest gap on each chromosome was 10.2 cM on average. The proportion of gaps less than and/or equal to 5.0 cM was averagely 98.1%. The markers on each chromosome ranged from 123 (chromosome 9) to 315 (chromosome 4) with a mean value of 224.6, the distance between adjacent markers ranged from 0.6 (chromosome 10) to 1.3 cM (chromosome 9) with an average distance of only 0.98 cM. Conclusion A high density sorghum genetic map was constructed in this study. The total length was 2158.1 cM covering all 10 chromosomes with a total number of 2246 SLAF markers. The construction of this map can provide detailed information for accurate gene localization and cloning and application of marker-assisted breeding. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3430-7) contains supplementary material, which is available to authorized users.