Characterization of the powdery mildew resistance locus in wheat breeding line Jimai 809 and its breeding application

Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a severe disease that affects the yield and quality of wheat. Popularization of resistant cultivars in production is the preferred strategy to control this disease. In the present study, the Chinese wheat breeding line Jimai 809 showed excellent agronomic performance and high resistance to powdery mildew at the whole growth stage. To dissect the genetic basis for this resistance, Jimai 809 was crossed with the susceptible wheat cultivar Junda 159 to produce segregation populations. Genetic analysis showed that a single dominant gene, temporarily designated PmJM809, conferred the resistance to different Bgt isolates. PmJM809 was then mapped on the chromosome arm 2BL and flanked by the markers CISSR02g-1 and CIT02g-13 with genetic distances 0.4 and 0.8 cM, respectively, corresponding to a physical interval of 704.12-708.24 Mb. PmJM809 differed from the reported Pm genes on chromosome arm 2BL in origin, resistance spectrum, physical position and/or genetic diversity of the mapping interval, also suggesting PmJM809 was located on a complex interval with multiple resistance genes. To analyze and screen the candidate gene(s) of PmJM809, six genes related to disease resistance in the candidate interval were evaluated their expression patterns using an additional set of wheat samples and time-course analysis post-inoculation of the Bgt isolate E09. As a result, four genes were speculated as the key candidate or regulatory genes. Considering its comprehensive agronomic traits and resistance findings, PmJM809 was expected to be a valuable gene resource in wheat disease resistance breeding. To efficiently transfer PmJM809 into different genetic backgrounds, 13 of 19 closely linked markers were confirmed to be suitable for marker-assisted selection. Using these markers, a series of wheat breeding lines with harmonious disease resistance and agronomic performance were selected from the crosses of Jimai 809 and several susceptible cultivars.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11032-024-01467-8.

[ST266 inhibits neointimal hyperplasia after arterial balloon injury in rats]

Objective    To examine the effect of Human Amnion-Derived Multipotent Progenitor (AMP) cells and their novel ST266 secretome on neointimal hyperplasia after arterial balloon injury in rats.Material and Methods    Sprague-Dawley male rats were randomly divided into four groups (n=7): Control (PBS) group, systemic ST266 group, systemic AMP group and local AMP implant group. Neointimal hyperplasia was induced in the iliac using a 2F Fogarty embolectomy catheter. After surgery, the rats in the ST266 group were treated with 0.1, 0.5, or 1ml ST266 iv daily. In the systemic AMP groups, a single dose (SD) of 0.5 ×106 or 1×106 AMP cells was injected via the inferior vena cava after arterial balloon injury. In local AMP implant groups, 1×106, 5×106, or 20×106 AMP cells were implanted in 300 µl Matrigel (Mtgl) around the iliac artery after balloon injury. The iliac arteries were removed for histologic analysis at 28 days after the surgery. Re-endothelialization index was measured at 10 days after balloon injury.Results    ST266 (1 ml) group had a lower level of the Neointima / Neointima+Media ratio (N / N+M) 0.3±0.1 vs 0.5±0.1, p=0.004) and luminal stenosis (LS) percentage (18.2±1.9 % vs 39.2±5.8 %, p=0.008) compared with the control group. Single-dose AMP (1×106) decreased LS compared to the control group (19.5±5.4 % vs 39.2±5.8 %, p=0.033). Significant reduction in N / N+M were found between implanted AMPs (20×106) and the control group (0.4±0.1 vs 0.5±0.1, p=0.003) and the Mtgl-only group (0.5±0.1, p=0.007). Implanted AMPs (20×106) decreased the LS compared with both the control (39.2±5.8 %, p=0.001) and Mtgl-only group (37.5±8.6 %, p=0.016). ST266 (1 ml) significantly increased the re-endothelialization index compared to the control (0.4±0.1 vs 0.1±0.1, p=0.002).Conclusion    ST266 and AMP cells reduce neointimal formation and increase the re-endothelialization index after arterial balloon injury. ST266 is potentially a novel, therapeutic agent to prevent vascular restenosis in human.

Effects of the different waxy proteins on starch biosynthesis, starch physicochemical properties and Chinese noodle quality in wheat

Noodles are an important food in Asia. Wheat starch is the most important component in Chinese noodles. Loss of the waxy genes leads to lower activity of starch synthesis enzymes and decreased amylose content that further affects starch properties and noodle quality. To study the effects of different waxy (Wx) protein subunits on starch biosynthesis and processing quality, the high-yielding wheat cultivar Jimai 22 was treated with the mutagen ethyl methane sulfonate (EMS) to produce a population of Wx lines and chosen 7 Wx protein combinations. The amylose content increased but swelling power decreased as the number of Wx proteins increased. Both GBSS activity and gene expression were the lowest for the waxy mutant, followed by the mutants with 1 Wx protein. The combinations of these mutant alleles lead to reductions in both RNA expression and protein levels. Noodles made from materials with 2 Wx protein subunits had the highest score, which agreed with peak viscosity. The influence of the Wx-B1 protein on amylose synthesis and noodle quality was the highest, whereas the influence of Wx-A1 protein was the lowest. Mutants with lower amylose content caused by the absence of 1 subunit, especially the Wx-B1 subunit, had superior noodle quality. Additionally, the identified mutant lines can be used as intermediate materials to improve wheat quality.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11032-022-01292-x.

Identification and Evaluation of Wheat-Aegilops bicornis Lines with Resistance to Powdery Mildew and Stripe Rust

Wheat pathogens, especially those causing powdery mildew and stripe rust, seriously threaten yield worldwide. Utilizing newly identified disease resistance genes from wheat relatives is an effective strategy to minimize disease damage. In this study, chromosome-specific molecular markers for the 3S^b and 7S^b chromosomes of Aegilops bicornis were developed using PCR-based landmark unique gene primers for screening wheat-A. bicornis progenies. Fluorescence in situ hybridization (FISH) was performed to further identify wheat-A. bicornis progenies using oligonucleotides probes Oligo-pSc119.2-1, Oligo-pTa535-1, and Oligo-(GAA)₈. After establishing A. bicornis 3S^b and 7S^b chromosome-specific FISH markers, Holdfast (common wheat)-A. bicornis 3S^b addition, 7S^b addition, 3S^b(3A) substitution, 3S^b(3B) substitution, 3S^b(3D) substitution, 7S^b(7A) substitution, and 7S^b(7B) substitution lines were identified by the molecular and cytological markers. Stripe rust and powdery mildew resistance, along with agronomic traits, were investigated to evaluate the breeding potential of these lines. Holdfast and Holdfast-A. bicornis progenies were all highly resistant to stripe rust, indicating that the stripe rust resistance might derive from Holdfast. However, Holdfast-A. bicornis 3S^b addition, 3S^b(3A) substitution, 3S^b(3B) substitution, and 3S^b(3D) substitution lines showed high resistance to powdery mildew while Holdfast was highly susceptible, indicating that chromosome 3S^b of A. bicornis carries previously unknown powdery mildew resistance gene(s). Additionally, the transfer of the 3S^b chromosome from A. bicornis to wheat significantly increased tiller number, but chromosome 7S^b has a negative effect on agronomic traits. Therefore, wheat germplasm containing A. bicornis chromosome 3S^b has potential to contribute to improving powdery mildew resistance and tiller number during wheat breeding.

Characterization, Identification and Evaluation of Wheat-Aegilops sharonensis Chromosome Derivatives

Aegilops sharonensis, a wild relative of wheat, harbors diverse disease and insect resistance genes, making it a potentially excellent gene source for wheat improvement. In this study, we characterized and evaluated six wheat-A. sharonensis derivatives, which included three disomic additions, one disomic substitution + monotelosomic addition and two disomic substitution + disomic additions. A total of 51 PLUG markers were developed and used to allocate the A. sharonensis chromosomes in each of the six derivatives to Triticeae homoeologous groups. A set of cytogenetic markers specific for A. sharonensis chromosomes was established based on FISH using oligonucleotides as probes. Molecular cytogenetic marker analysis confirmed that these lines were a CS-A. sharonensis 2S^sh disomic addition, a 4S^sh disomic addition, a 4S^sh (4D) substitution + 5S^shL monotelosomic addition, a 6S^sh disomic addition, a 4S^sh (4D) substitution + 6S^sh disomic addition and a 4S^sh (4D) substitution + 7S^sh disomic addition line, respectively. Disease resistance investigations showed that chromosome 7S^sh of A. sharonensis might harbor a new powdery mildew resistance gene, and therefore it has potential for use as resistance source for wheat breeding.

Molecular and genetic dissection of the USDA rice mini-core collection using high-density SNP markers

Molecular tools and knowledge of crop germplasm are vital for their effective utilization. In this study, we developed 40,866 high-quality and well distributed SNPs for a rice mini-core collection (RMC) developed by the United States Department of Agriculture (USDA). The high-quality SNPs clustered the USDA-RMC into five subpopulations (Ind, indica; Aus, aus; Afr, African rice; TeJ, temperate japonica; TrJ, tropical japonica) and one admixture (Adm). This classification was further confirmed by phylogenetic and principal component analyses. The rice ARO (aromatic) subpopulation of previous studies was re-assigned with Adm and the WD (wild-type) subpopulation was re-defined to the Afr subpopulation because most of its accessions are African cultivated rice. The Aus and Ind subpopulations had a substantially wider genetic variation than the TrJ and TeJ subpopulations. The genetic diversities were much larger between the Ind or Aus subpopulation and the TrJ or TeJ subpopulation than between the Afr subpopulation and the Ind, Aus, TrJ or TeJ subpopulation. Comparative agronomic trait analysis between the subpopulations also supported the genetic structure and variation of the RMC, and suggested the existence of extensive variation in the genes controlling agronomic traits among them. Furthermore, analysis of ancestral membership of the RMC accessions revealed that reproductive barrier or wide incompatibility existed between the Indica and Japonica groups, while gene flow occurred between them. These results provide high-quality SNPs and knowledge of genetic structure and diversity of the USDA-RMC necessary for enhanced rice research and breeding.

Lewis-base-catalysed selective reductions of ynones with a mild hydride donor

Nucleophilic phosphines catalyze efficient 1,2-reductions of ynones employing pinacolborane as a mild hydride donor in the presence of alcohol additives.

Role of microRNA-129-5p in osteoblast differentiation from bone marrow mesenchymal stem cells

Mesenchymal stem cells derived from bone marrow have the capacity to differentiate into osteoblast, chondrocyte, nerve cell and myocardial cell in vitro, which are an ideal engraft in tissue-engineered repair. Osteoblast differentiation is a vital process in maintaining bone homeostasis in which various transcriptional factors, including signaling molecules, and microRNAs (miRNAs). In this research, human bone marrow mesenchymal stem cells (hBMSCs) were induced differentiation into osteoblast in vitro after over-expression of miR-129-5p. The results showed that the hBMSCs could induce differentiation into osteoblast under the special condition medium, but when the miR-129-5p was over-expressed in hBMSCs, the differentiated efficiency and induced time of osteoblast from hBMSCs could be promoted. This reason was demonstrated that signal transducer and activator of transcription 1 (STAT1) was a transcriptional repressor of osteoblast gene (Runx 2) expression during osteoblast differentiation, miR-129-5p reduced STAT1 levels, leading to the accumulation of correctly spliced Runx 2 mRNA and a dramatic increase in Runx 2 protein.

Association of GSTTI and GSTM1 variants with acute myeloid leukemia risk

We aimed to investigate the relationships between polymorphisms of the glutathione S-transferases (GSTs) GSTM1, GSTTI, and GSTP1 and the risk of developing acute myeloid leukemia (AML). A total of 206 AML cases and 231 controls were collected for our study. The genotyping of GSTs (GSTM1, GSTTI, and GSTP1) was based upon the duplex polymerase chain reaction with the confronting two-pair primer (PCR-CTPP) method. Individuals carrying null GSTTI and GSTM1 genotypes had a 1.52- and 1.78-fold increased risk of developing acute leukemia, respectively, compared to non-null genotype carriers (P < 0.05). A high risk was observed in those carrying a combination of null genotypes of GSTM1 and GSTTI with GSTP1-Val allele genotypes when compared with those carrying wild-type genotypes, with an odds ratio (95% confidence interval) of 3.62 (1.53-8.82) (P < 0.05). These findings indicate that genetic variants of GSTTI and GSTM1 significantly increase the risk of developing AML. Our study offers important insights into the molecular etiology of AML.

[Study on the reaction mechanism and application of eldest amine basic dye with nitrite]

In this paper, the reaction of eldest amine basic dye with nitrite in hydrochloric acid medium by ultraviolet-visible spectrometry, electrochemistry analysis, Fourier transform infrared spectrometer and nuclear magnetic resonance was studied systematically. The reaction of its structure and effect was preliminarily understood. It is realized that there is diazotization-coupling or diazo-reaction mechanism, generating triazene or diazo-compound. It has magnificent meaning for perfecting, applying this kind of basic dye and instituting a ultraviolet-visible spectrometry or electrochemistry analysis new method of measuring nitrite.

[Determination of trace amounts of nitrite and reaction mechanism by triple-wavelength spectrophotometry]

A new method was proposed for the determination of nitrite ion by triple-wavelength spectrophotometry. This limits ranges of determination are 0-0.560 mg.L-1 nitrite ion at 599.1 nm, 420.6 nm and 283.4 nm. It has been applied to analysis trace amounts of nitrite ion of standard sample and environmental water with satisfactory result, the relative error was less 1.7% and recovery of the real samples was between 96.5 and 100.0%. This method is based on the diazotization-coupling react of thionine with nitrite ion in acidic medium, the mole ratio of thionine:nitrite is 2:1 by the continuous variation and mole ratio method.