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Powdery mildew is a key airborne foliar disease of barley in southeastern and southwestern China. Barley varieties usually partially or wholly lose resistance to the pathogen Blumeria graminis (DC.) f. sp. hordei 3 to 5 years after release due to the frequent acquirements of new virulences in the pathogen population. However, no B. graminis f. sp. hordei virulence detection has been carried out in the recent decade and, thus, no information is available on the present virulence components and major pathotypes in epidemic regions. Twenty-one near-isogenic lines of Pallas were selected to detect B. graminis f. sp. hordei virulence variation, with 97 pathotypes identified from the isolates collected from 2015 to 2019. The virulence complexities ranged from 1 to 12, with 1.5 isolates on average assigned per pathotype, suggesting a natural trait of high pathotype diversity and low virulence complexity in the Chinese B. graminis f. sp. hordei populations. Eleven high-virulence pathotypes were detected in the traditional barley-growing regions in Yunnan and Zhejiang. Six virulent pathotypes to resistance gene mlo-5 were detected only in the two traditional epidemic regions, with a virulence frequency (VF) of 4.8% (7 of 147). Compared with the results from a decade ago, VFs for resistance alleles Mla3, mlo-5, Mla6 + Mla14, Mla7 + Mlk, Mlg + MlCP, and Mla13 + MlRu3 + MlaRu4 increased from 0 to 0.7 to 25.8%. Isolates from Yunnan and Zhejiang had similar virulence profiles, which differed from those identified in Tibet. In addition, genetic diversities differed in the isolate groups collected from Tibet, Yunnan, and Zhejiang.
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Ascomicetos , Virulência/genética , China , Ascomicetos/genética , Variação GenéticaRESUMO
Powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) is a serious fungal wheat disease of wheat worldwide. Host resistance is considered to be the most environmentally friendly and efficient approach against this disease. Wheat breeding line GR18-1 showed resistance to powdery mildew at both seedling and adult stages for several years. Genetic analysis indicated that a single dominant gene, tentatively designated as PmGR-18, conferred powdery mildew resistance in GR18-1. Bulked segregant analysis and marker analysis showed that PmGR-18 was located in the Pm4 interval on chromosome arm 2AL and was flanked by the markers Xwgrc763 and Xwgrc872, respectively, with genetic distances of 0.5 and 1.0 cM corresponding to a physical interval of 1.13 Mb based on the Chinese Spring reference genome sequence v2.1. Using homology-based cloning and Sanger sequencing, we found that the sequence of PmGR-18 was totally consistent with that of Pm4d. qRT-PCR analysis showed that the expression levels of two splicing variants Pm4d_V1 and Pm4d_V2 in GR18-1 were significantly upregulated after inoculating with Bgt isolate E09, and the level of Pm4d_V2 was significantly lower than that of Pm4d_V1 at most of the time points, suggesting a different resistance pattern may be involved in the genotype. To facilitate the transfer of PmGR-18 in marker-assisted selection (MAS) breeding, the flanked markers Xwgrc763 and Xwgrc872 and the functional marker JS717/JS718 were tested and confirmed to enable the tracking of PmGR-18 when it transferred into those susceptible cultivars.
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Resistência à Doença , Triticum , Triticum/genética , Triticum/microbiologia , Mapeamento Cromossômico , Marcadores Genéticos , Resistência à Doença/genética , Alelos , Melhoramento Vegetal , Erysiphe/genéticaRESUMO
KEY MESSAGE: A new adult plan resistance gene YrBm for potentially durable resistance to stripe rust was mapped on wheat chromosome arm 4BL in landrace Baimangmai. SSR markers closely flanking YrBm were developed and validated for use in marker-assisted selection. The wheat stripe rust pathogen Puccinia striiformis f. sp. tritici (Pst) frequently acquires new virulences and rapidly adapts to environmental stress. New virulences in Pst populations can cause previously resistant varieties to become susceptible. If those varieties were widely grown, consequent epidemics can lead to yield losses. Identification and deployment of genes for durable resistance are preferred method for disease control. The Chinese winter wheat landrace Baimangmai showed a high level of adult plant resistance (APR) to stripe rust in a germplasm evaluation trial at Langfang in Hebei province in 2006 and has continued to confer high resistance over the following 15 years in field nurseries in Hebei, Sichuan and Gansu. A recombinant inbred line population of 200 F10 lines developed from a cross of Baimangmai and a susceptible genotype segregated for APR at a single locus on chromosome 4BL; the resistance allele was designated YrBm. Allelism tests of known Yr genes on chromosome 4B and unique closely flanking marker alleles Xgpw7272189 and Xwmc652164 among a panel of Chinese wheat varieties indicated that YrBm was located at a new locus. Moreover, those markers can be used for marker-assisted selection in breeding for stripe rust resistance.
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Basidiomycota , Triticum , China , Mapeamento Cromossômico , Resistência à Doença/genética , Melhoramento Vegetal , Doenças das Plantas/genética , Triticum/genéticaRESUMO
Spot blotch caused by Cochliobolus sativus has become an important disease in the wheat-growing regions in China that has resulted from changes in the regional climate, agricultural cultivation patterns, and the susceptible wheat varieties that are widely grown. Little information is available about virulence variability and pathogenic specialization of the C. sativus isolates from major wheat-growing regions in China. Here, 12 representative wheat varieties and foundation breeding stocks were selected to characterize the pathotypes of C. sativus isolates from infected wheat plants. Based on the infection phenotypes in the 12 differential genotypes at the seedling stage, 70 Chinese pathotypes were identified from 110 isolates and clustered into three virulence groups. The high virulence isolates were collected from wheat leaves, crowns, and roots, with most (10 of 14) from the Henan province in the Huang-Huai plain. No relationship was evident between virulence variability of C. sativus isolates and their geographic origins or types of diseased wheat tissues. C. sativus showed a significant pathogenic specialization in hosts of wheat and barley. Most of the wheat isolates (50 of 65) were avirulent to all the differential barley genotypes, and a few were virulent only to highly susceptible barley genotypes. These results indicated that C. sativus isolates from the wheat-growing regions in China varied considerably for their virulence in wheat varieties, and showed significant pathogenic specialization to the wheat and barley hosts.
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Bipolaris , Doenças das Plantas/microbiologia , Triticum/microbiologia , Bipolaris/genética , Bipolaris/patogenicidade , Melhoramento Vegetal , Doenças das Plantas/genética , Virulência/genéticaRESUMO
Remanufactured mechanical products with high-added value are generally claimed to gain environmental benefits. These claims were made based on different products and assessment methodologies. The variability of life cycle assessment (LCA) results precludes a meaningful comparison across products and studies. This paper aims to critically and systematically evaluate the lifecycle environmental performance of remanufactured products compared with their new counterparts and to identify the key factors, strengths, and limitations in the assessment procedure. Faced with the noteworthy variations, we closely examined and harmonized the unit function, allocation approach, system boundary, impact assessment method, and the underlying assumptions in screened 20 papers regarding 11 types of products. The environmental indicators adopted in this study were global warming potential (GWP) and primary energy consumption (PEC). In terms of these two indicators, the environmental burdens of remanufactured products relative to newly manufactured alternatives were harmonized to the comparison ratios. With these harmonized samples, descriptive statistics were calculated using Monte Carlo Simulation to disclose the variations of comparison results and identify the general tendency. Results of this meta-study showed that remanufacturing could contribute to over 50% reduction for GWP when usage and end-of-life stages were excluded from the life cycle. The GWP and PEC of remanufactured mechanical products account for 28.5% and 25.9% of the new counterparts, respectively, on average. This meta-analysis of comparative LCAs on new and remanufactured products would advance the understanding of the environmental advantages of remanufacturing.
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Comércio , Aquecimento Global , Animais , Estágios do Ciclo de VidaRESUMO
OBJECTIVE: To further explore the role of BCL-2 associated anthanogen-1 (BAG-1) in neuronal apoptosis and whether the effect of BAG-1 depends on heat shock protein 70 (HSP70). METHODS: RNA interference (RNAi) technology was used to inhibit the expression of BAG-1 in SH-SY5Y cells. Hypoxia-reoxygenation injury model in the SH-SY5Y cells was established. Cell Counting Kit-8 (CCK-8) was performed for cell viability. Annexin V-APC/7-AAD double-staining followed by flow cytometry was used to measure cell apoptosis. Quantitative reverse-transcription polymerase chain reaction and Western blot analysis were used to detect the messenger RNA (mRNA) and protein expression of genes, respectively. RESULTS: BAG-1 gene silencing decreased SH-SY5Y cell viability and promoted SH-SY5Y cell apoptosis after hypoxia-reoxygenation. However, the down-regulation of BAG-1 had no effect on the mRNA and protein expression of HSP70. CONCLUSION: BAG-1 could protect SH-SY5Y cells from the hypoxia-reoxygenation injury without affecting HSP70 expression.
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Biomarcadores Tumorais/metabolismo , Proteínas de Ligação a DNA/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP70/metabolismo , Neuroblastoma/patologia , RNA Interferente Pequeno/genética , Fatores de Transcrição/antagonistas & inibidores , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Choque Térmico HSP70/genética , Humanos , Neuroblastoma/genética , Neuroblastoma/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Células Tumorais CultivadasRESUMO
Spot blotch, caused by the fungal pathogen Cochliobolus sativus, is a limiting factor for barley (Hordeum vulgare) production in northeast China, which causes significant grain yield losses and kernel quality degradation. It is critical to determine the virulence diversity of C. sativus populations for barley resistance breeding and the judicious grouping of available resistance varieties according to the predominant pathotypes in disease epidemic regions. With little information on the barley pathogen in China, this study selected 12 typical barley genotypes to differentiate the pathotypes of C. sativus isolates collected in China. Seventy-one isolates were grouped into 19 Chinese pathotypes based on infection responses. Seventeen isolates were classified as pathotype 3, which has only been identified in China, whereas most (52 of 71) were classified as pathotype 1. All of the tested isolates had low virulence on the North Dakota (ND) durable, resistant line ND B112. Using 22 selected amplified fragment-length polymorphism (AFLP) primer combinations, genetic polymorphism was used to analyze 68 isolates, which clustered into three distinct groups using the unweighted pair group method average with the genetic distance coefficient. No relationship was found between the virulence of isolates and their origins. Isolates of the same pathotype or those collected from the same location did not group into clusters based on the AFLP analysis.
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Ascomicetos , Variação Genética , Hordeum , Virulência , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Ascomicetos/classificação , Ascomicetos/genética , China , Hordeum/microbiologia , Doenças das Plantas/microbiologia , Polimorfismo Genético , Virulência/genéticaRESUMO
Puccinia striiformis f. sp. tritici (Pst) is adept at overcoming resistance in wheat cultivars, through variations in virulence in the western provinces of China. To apply disease management strategies, it is essential to understand the temporal and spatial dynamics of Pst populations. This study aimed to evaluate the virulence and molecular diversity of 84 old Pst isolates, in comparison to 59 newer ones. By using 19 Chinese wheat differentials, we identified 98 pathotypes, showing virulence complexity ranging from 0 to 16. Associations between 23 Yr gene pairs showed linkage disequilibrium and have the potential for gene pyramiding. The new Pst isolates had a higher number of polymorphic alleles (1.97), while the older isolates had a slightly higher number of effective alleles, Shannon's information, and diversity. The Gansu Pst population had the highest diversity (uh = 0.35), while the Guizhou population was the least diverse. Analysis of molecular variance revealed that 94% of the observed variation occurred within Pst populations across the four provinces, while 6% was attributed to differences among populations. Overall, Pst populations displayed a higher pathotypic diversity of H > 2.5 and a genotypic diversity of 96%. This underscores the need to develop gene-pyramided cultivars to enhance the durability of resistance.
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Doenças das Plantas , Puccinia , Triticum , Puccinia/patogenicidade , Puccinia/genética , Triticum/microbiologia , Triticum/genética , China , Virulência/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Variação Genética , Desequilíbrio de Ligação , Resistência à Doença/genéticaRESUMO
Fungal diseases, such as powdery mildew and rusts, significantly affect the quality and yield of wheat. Pyramiding diverse types of resistance genes into cultivars represents the preferred strategy to combat these diseases. Moreover, achieving collaborative improvement between diseases resistance, abiotic stress, quality, and agronomic and yield traits is difficult in genetic breeding. In this study, the wheat cultivar, Guinong 29 (GN29), showed high resistance to powdery mildew and stripe rust at both seedling and adult plant stages, and was susceptible to leaf rust at the seedling stage but slow resistance at the adult-plant stage. Meanwhile, it has elite agronomic and yield traits, indicating promising coordination ability among multiple diseases resistance and other key breeding traits. To determine the genetic basis of these elite traits, GN29 was tested with 113 molecular markers for 98 genes associated with diseases resistance, stress tolerance, quality, and adaptability. The results indicated that two powdery mildew resistance (Pm) genes, Pm2 and Pm21, confirmed the outstanding resistance to powdery mildew through genetic analysis, marker detection, genomic in situ hybridization (GISH), non-denaturing fluorescence in situ hybridization (ND-FISH), and homology-based cloning; the stripe rust resistance (Yr) gene Yr26 and leaf rust resistance (Lr) genes Lr1 and Lr46 conferred the stripe rust and slow leaf rust resistance in GN29, respectively. Meanwhile, GN29 carries dwarfing genes Rht-B1b and Rht-D1a, vernalization genes vrn-A1, vrn-B1, vrn-D1, and vrn-B3, which were consistent with the phenotypic traits in dwarf characteristic and semi-winter property; carries genes Dreb1 and Ta-CRT for stress tolerance to drought, salinity, low temperature, and abscisic acid (ABA), suggesting that GN29 may also have elite stress-tolerance ability; and carries two low-molecular-weight glutenin subunit genes Glu-B3b and Glu-B3bef which contributed to high baking quality. This study not only elucidated the genetic basis of the elite traits in GN29 but also verified the capability for harmonious improvement in both multiple diseases resistance and other comprehensive traits, offering valuable information for breeding breakthrough-resistant cultivars.
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Ascomicetos , Resistência à Doença , Doenças das Plantas , Triticum , Triticum/genética , Triticum/microbiologia , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Ascomicetos/patogenicidade , Ascomicetos/fisiologia , Melhoramento Vegetal/métodos , Fenótipo , Basidiomycota/fisiologia , Basidiomycota/patogenicidade , Genes de Plantas , Mapeamento CromossômicoRESUMO
This study aimed to assess the preventive role of rehabilitation nursing in the formation of deep vein thrombosis (DVT) in the lower limbs after fracture and its effect on the patient's quality of life. Ninety patients with lower limb fractures were randomly divided into a study group (nâ =â 45) and a control group (nâ =â 45). Patients in the control group received routine care postoperatively, whereas patients in the study group received rehabilitation nursing intervention on the same postoperative day. A follow-up examination was conducted after 3 months. The occurrence rate of lower limb DVT (LDVT) complications, hemorheology, quality of life (SF-36) scores, coagulation profile, and nursing satisfaction were compared between the groups. After the intervention, the study group presented with lower extremity DVT and higher hemorheology indices than those of the control group (Pâ <â .05). The SF-36 scores of both groups increased, but the increase in SF-36 scores in the study group was more significant (Pâ <â .001). The satisfaction level of the patients in the study group with nursing services was higher than that of the control group (Pâ =â .004). Coagulation indicators can be effectively adjusted and the occurrence of postoperative complications can be reduced in patients undergoing spine fracture surgery such as DVT via standardized rehabilitation care, thereby improving patients' quality of life and nursing conditions.
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Fraturas Ósseas , Enfermagem em Reabilitação , Trombose Venosa , Humanos , Qualidade de Vida , Extremidade Inferior/cirurgia , Extremidade Inferior/irrigação sanguínea , Fraturas Ósseas/complicações , Fraturas Ósseas/cirurgia , Trombose Venosa/etiologiaRESUMO
Inorganic lead halide perovskite is one of the most excellent fluorescent materials, and it plays an essential role in high-definition display and visible light communication (VLC). Its photochromic properties and stability determine the final performance of light-emitting devices. However, efficiently synthesizing perovskite with high quality and stability remains a significant challenge. Here, we develop a facile and environmentally friendly method for preparing high-stability and strong-emission CsPbBr3/Cs4PbBr6 composites using ultrasonication and liquid paraffin. Tuning the contents of liquid paraffin, bright-emission CsPbBr3/Cs4PbBr6 composite powders with a maximum PLQY of 74% were achieved. Thanks to the protection of the Cs4PbBr6 matrix and liquid paraffin, the photostability, thermostability, and polar solvent stability of CsPbBr3/Cs4PbBr6-LP are significantly improved compared to CsPbBr3 quantum dots and CsPbBr3/Cs4PbBr6 composites that were prepared without liquid paraffin. Moreover, the fabricated CsPbBr3/Cs4PbBr6-LP-based WLEDs show excellent luminescent performance with a power efficiency of 129.5 lm/W and a wide color gamut, with 121% of the NTSC and 94% of the Rec. 2020, demonstrating a promising candidate for displays. In addition, the CsPbBr3/Cs4PbBr6-LP-based WLEDs were also demonstrated in a VLC system. The results suggested the great potential of these high-performance WLEDs as an excitation light source to achieve VLC.
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In the present study, the microstructure and properties characteristics of W-20Cu nano-crystallite composites were investigated. Characterization techniques like XRD and SEM have been used to study the crystallite size of W-Cu powder obtained by mechanical alloying. As well as, the effect of milling time on the microstructure and properties of W-20Cu composites was discussed. The results show that with increasing milling time, the crystallite size of W-Cu composite powder decreased and kept steady at last, and the crystallite size of W(Cu) solid solution was 6.6 nm for milling 20 h. The microstructure of W-20Cu composites became homogeneous and tungsten crystallite size became fine. The relative density and bending strength of W-20Cu composites increased. The value of thermal conductivity peaked when milling time was 20 h.
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Nanocrystalline FeAl powder is synthesized by subsequent heat treating the Fe50Al50 (at.%) alloy prepared by mechanical alloying. During annealing the milled FeAl powder, the grain growth of B2-FeAl occurs with the order transformation from Fe(Al) to B2-FeAl. The activation energy for the nanocrystalline FeAl growth is calculated to be 534.9 kJ/mol, according to the kinetics theory of nanocrystalline growth. The grain growth of FeAl is significantly inhibited especially at elevated temperature.
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BACKGROUND: Central poststroke pain (CPSP) is a neuropathic pain syndrome that can occur after a cerebrovascular accident. It has negative effects on mood, sleep, rehabilitation, and quality of life in stroke patients. This systematic review assessed the efficacy and safety of nonpharmacological therapies for treating CPSP. METHODS: The Cochrane, PubMed, Embase, and Web of Science databases were systematically searched for studies from inception to August 2020. Two authors worked independently and in duplicate to identify suitable studies. RESULTS: Eleven studies were identified. Pain related to CPSP was ameliorated by precentral gyrus stimulation (Pâ=â.01), caloric vestibular stimulation (Pâ=â0.004), transcranial direct current stimulation (Pâ<â.05), and bee venom acupuncture point injection (Pâ=â.009). Acupuncture (Pâ=â.72) and electroacupuncture therapies (Pâ>â.05) were as effective for thalamic pain as oral carbamazepine treatment. Motor cortex stimulation, but not deep brain stimulation (DBS), was effective for treating refractory CPSP, and appeared to be more effective than thalamic stimulation for controlling bulbar pain secondary to Wallenberg syndrome. However, DBS in the ventral striatum or anterior limb of the internal capsule improved depression (Pâ=â.020) and anxiety in patients with refractory CPSP. Some serious adverse events were reported in response to invasive electrical brain stimulation, but most of these effects recovered with treatment. CONCLUSIONS: Nonpharmacological therapies appear to be effective in CPSP, but the evidence is relatively weak. Invasive electrical brain stimulation can be accompanied by serious adverse events, but most patients recover from these effects.
Assuntos
Neuralgia/terapia , Acidente Vascular Cerebral/complicações , Terapia por Acupuntura , Terapia por Estimulação Elétrica , Humanos , Neuralgia/etiologia , Estimulação Magnética TranscranianaRESUMO
We introduce here a simple method of integrating 45 degrees total internal reflection micro-mirrors with polymer optical waveguides by an improved tilted beam photolithography on printed circuit boards to provide surface normal light coupling between waveguides and optoelectronic devices for optical interconnects. De-ionized water is used to couple ultraviolet beam through the waveguide core polymer layer at 45 degrees angle during the photo exposure process. This technique is compatible with PCB manufacturing facility and suitable to large panel board-level manufacturing. The mirror slope is controlled accurately (within +/- 1 degrees) with high repeatability. The insertion loss of an uncoated micro-mirror is measured to be 1.6 dB.
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Basic leucine zipper (bZIP) membrane-bound transcription factors (MTFs) play important roles in regulating plant growth and development, abiotic stress responses, and disease resistance. Most bZIP MTFs are key components of signaling pathways in endoplasmic reticulum (ER) stress responses. In this study, a full-length cDNA sequence encoding bZIP MTF, designated TabZIP74, was isolated from a cDNA library of wheat near-isogenic lines of Taichung29*6/Yr10 inoculated with an incompatible race CYR32 of Puccinia striiformis f. sp. tritici (Pst). Phylogenic analysis showed that TabZIP74 is highly homologous to ZmbZIP60 in maize and OsbZIP74 in rice. The mRNA of TabZIP74 was predicted to form a secondary structure with two kissing hairpin loops that could be spliced, causing an open reading frame shift immediately before the hydrophobic region to produce a new TabZIP74 protein without the transmembrane domain. Pst infection and the abiotic polyethylene glycol (PEG) and abscisic acid (ABA) treatments lead to TabZIP74 mRNA splicing in wheat seedling leaves, while both spliced and unspliced forms in roots were detected. In the confocal microscopic examination, TabZIP74 is mobilized in the nucleus from the membrane of tobacco epidermal cells in response to wounding. Knocking down TabZIP74 with barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) enhanced wheat seedling susceptibility to stripe rust and decreased drought tolerance and lateral roots of silenced plants. These findings demonstrate that TabZIP74 mRNA is induced to splice when stressed by biotic and abiotic factors, acts as a critically positive regulator for wheat stripe rust resistance and drought tolerance, and is necessary for lateral root development.
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BACKGROUND: Approximately 10% to 30% patients develop delayed encephalopathy after acute CO poisoning (DEACMP). No specific treatment is available and poor prognosis is a characteristic of this disease. We aimed to evaluate the efficacy and safety of all therapies that have been tried in randomized controlled trial (RCT) for DEACMP. METHODS: We conducted a systematic search of the Cochrane, Embase, PubMed, and Web of Science databases. RESULTS: Overall, 4 RCTs were identified in our study. Both hyperbaric oxygen (HBO) and mesenchymal stem cell (MSC) transplantation were effective in DEACMP, and MSC seemed to be superior to HBO. The addition of dexamethasone, N-butylphthalide, or XingZhi-YiNao granules into HBO, or butylphthalide into MSC could achieve better neurological recovery in DEACMP patients but did not significantly increase the incidence of adverse events. CONCLUSION: Several therapies have shown positive results in treating DEACMP and need to be proven by further studies.
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Encefalopatias/etiologia , Encefalopatias/terapia , Intoxicação por Monóxido de Carbono/complicações , Benzofuranos/uso terapêutico , Dexametasona/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Oxigenoterapia Hiperbárica/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de TempoRESUMO
Wheat stripe (yellow) rust, caused by Puccinia striiformis West. f. sp. tritici (Pst), is one of the most destructive diseases in many wheat-growing countries, especially in China, the largest stripe rust epidemic area in the world. Growing the resistant cultivars is an effective, economic and environmentally friendly way to control this disease. Wheat cultivar Zhengmai 7698 has shown a high-level resistance to wheat stripe rust. To elucidate its genetic characteristics and location of the resistance gene, Zhengmai 7698 was crossed with susceptible variety Taichung 29 to produce F1, F2 and BC1 progeny generations. The genetic analysis showed that the stripe rust resistance in Zhengmai 7698 to Pst predominant race CYR32 was controlled by a single-dominant gene, named YrZM. Bulked segregant analysis and simple sequence repeat (SSR) markers were used to map the gene. Four SSR markers, Xbarc198, Xwmc179, Xwmc786 and Xwmc398 on chromosome 6BL were polymorphic between the parents and resistance, and susceptible bulks. A linkage genetic map was constructed using 212 F2 plants in the sequential order of Xwmc398, Xwmc179, YrZM, Xbarc198, Xwmc786. As this gene is effective against predominant race CYR32, it is useful in combination with other resistance genes for developing new wheat cultivars with resistance to stripe rust.
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Resistência à Doença/genética , Doenças das Plantas/genética , Triticum/genética , Basidiomycota/patogenicidade , China , Mapeamento Cromossômico , Ligação Genética/genética , Marcadores Genéticos , Genótipo , Repetições de Microssatélites/genética , Doenças das Plantas/microbiologia , Polimorfismo Genético , Triticum/crescimento & desenvolvimento , Triticum/microbiologiaRESUMO
Plant-specific NAC transcription factors (TFs) constitute a large family and play important roles in regulating plant developmental processes and responses to environmental stresses, but only some of them have been investigated for effects on disease reaction in cereal crops. Virus-induced gene silencing (VIGS) is an effective strategy for rapid functional analysis of genes in plant tissues. In this study, TaNAC1, encoding a new member of the NAC1 subgroup, was cloned from bread wheat and characterized. It is a TF localized in the cell nucleus, and contains an activation domain in its C-terminal. TaNAC1 was strongly expressed in wheat roots and was involved in responses to infection by the obligate pathogen Puccinia striiformis f. sp. tritici and defense-related hormone treatments such as salicylic acid (SA), methyl jasmonate, and ethylene. Knockdown of TaNAC1 with barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) enhanced stripe rust resistance. TaNAC1-overexpression in Arabidopsis thaliana plants gave enhanced susceptibility, attenuated systemic-acquired resistance to Pseudomonas syringae DC3000, and promoted lateral root development. Jasmonic acid-signaling pathway genes PDF1.2 and ORA59 were constitutively expressed in transgenic plants. TaNAC1 overexpression suppressed the expression levels of resistance-related genes PR1 and PR2 involved in SA signaling and AtWRKY70, which functions as a connection node between the JA- and SA-signaling pathways. Collectively, TaNAC1 is a novel NAC member of the NAC1 subgroup, negatively regulates plant disease resistance, and may modulate plant JA- and SA-signaling defense cascades.
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Multispectral imaging has shown promise in subcutaneous vein detection and localization in human subjects. While many limitations of single-wavelength methods are addressed in multispectral vein detection methods, their performance is still limited by artifacts arising from background skin reflectance and optimality of postprocessing algorithms. We propose a background removal technique that enhances the contrast and performance of multispectral vein detection. We use images acquired at visible wavelengths as reference for removing skin reflectance background from subcutaneous structures in near-infrared images. Results are validated by experiments on human subjects.