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1.
Artigo em Inglês | MEDLINE | ID: mdl-34614483

RESUMO

In this work, by using femtosecond angle-resolved spectroscopic imaging technique, the ultrafast dynamics of confined exciton-polaritons in an optical induced potential well based on a ZnO whispering-gallery microcavity is explicitly visualized. The sub-picosecond transition between succeeding quantum harmonic oscillator states can be experimentally distinguished. The landscape of the potential well can be modified by the pump power, the spatial distance and the time delay of the two input laser pulses. Clarifying the underlying mechanism of the polariton harmonic oscillator is interesting for the applications of polariton-based optoelectronic devices and quantum information processing.

2.
Plant Mol Biol ; 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34586580

RESUMO

KEY MESSAGE: Nicotiana benthamiana acylsugar acyltransferase (ASAT) is required for protection against desiccation and insect herbivory. Knockout mutations provide a new resource for investigation of plant-aphid and plant-whitefly interactions. Nicotiana benthamiana is used extensively as a transient expression platform for functional analysis of genes from other species. Acylsugars, which are produced in the trichomes, are a hypothesized cause of the relatively high insect resistance that is observed in N. benthamiana. We characterized the N. benthamiana acylsugar profile, bioinformatically identified two acylsugar acyltransferase genes, ASAT1 and ASAT2, and used CRISPR/Cas9 mutagenesis to produce acylsugar-deficient plants for investigation of insect resistance and foliar water loss. Whereas asat1 mutations reduced accumulation, asat2 mutations caused almost complete depletion of foliar acylsucroses. Three hemipteran and three lepidopteran herbivores survived, gained weight, and/or reproduced significantly better on asat2 mutants than on wildtype N. benthamiana. Both asat1 and asat2 mutations reduced the water content and increased leaf temperature. Our results demonstrate the specific function of two ASAT proteins in N. benthamiana acylsugar biosynthesis, insect resistance, and desiccation tolerance. The improved growth of aphids and whiteflies on asat2 mutants will facilitate the use of N. benthamiana as a transient expression platform for the functional analysis of insect effectors and resistance genes from other plant species. Similarly, the absence of acylsugars in asat2 mutants will enable analysis of acylsugar biosynthesis genes from other Solanaceae by transient expression.

3.
ACS Nano ; 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34558905

RESUMO

Silver nanowires (Ag NWs) present prominent waveguiding properties of subwavelength light due to their nanoconfinement with propagating surface plasmons, which is of great importance for on-chip integration of nanophotonic devices and optical computation. Such propagating plasmons also exert plasmonic forces, which can be utilized to manipulate nanoparticles (NPs) beyond the diffraction limit. However, such controllability is spatially limited to the near fields, whereas a large portion of uncontrolled particles are randomly deposited on the chips, which could be detrimental to the integrated optical devices. Herein we shine continuous wave laser at one end of the Ag NW immersed in AgNO3 solution to launch the propagating surface plasmons. The laser irradiation also induces the photoreduction of Ag+ ions to locally generate tiny Ag NPs, which evolve into large Ag flake branches closer to the other end of the Ag NW. Such a peculiar growth is due to the synergistic effect of plasmonic forces and the thermophoretic/thermo-osmosis forces induced by temperature gradient. These branched Ag NWs with sharp angles are intrinsically chiral, which can be partially controlled by changing the irradiation location, forming plasmonic chiral enantiomers. The circular differential scattering (CDS) response of these branched Ag NWs can be as large as 40%, which can be used for chiral enantiomer sensing with spectral dissymmetric factor up to 4 nm induced by phenylalanine. This plasmon-directed on-wire growth not only offers a facile approach for generating plasmonic chiral nanostructures with remote controllability, but also provides significant insights on the synergistic effect of plasmonic forces and thermal-induced forces, which has great implications for self-assembly and integration of on-chip optics.

4.
ACS Nano ; 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34546029

RESUMO

Plasmonic metasurfaces with the photothermal effect have been increasingly investigated for optofluidics. Meanwhile, along with the expanding application of circularly polarized light, a growing number of investigations on chiral plasmonic metasurfaces have been conducted. However, few studies have explored the chirality and the thermal-induced convection of such systems simultaneously. This paper aims to theoretically investigate the dynamics of the thermally induced fluid convection of a chiral plasmonic metasurface. The proposed metasurface exhibits giant circular dichroism in absorption and thus leads to a strong photothermal effect. On the basis of the multiphysical analysis, including optics, thermodynamics, and hydrodynamics, we propose a concept of chiral spectroscopy termed optofluidic circular dichroism. Our results show that different fluid velocities of thermally induced convection appear around a chiral plasmonic metasurface under different circularly polarized excitation. The chiral fluid convection is induced by an asymmetric heat distribution generated by absorbed photons in the plasmonic heater. This concept can be potentially used to induce chiral fluid convection utilizing the chiral photothermal effect. Our proposed structure can potentially be used in various optofluidics applications related to biochemistry, clinical biology, and so on.

5.
Int J Mol Sci ; 22(17)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34502445

RESUMO

The dried root of Salvia miltiorrhiza is a renowned traditional Chinese medicine that was used for over 1000 years in China. Salvianolic acid B (SalB) is the main natural bioactive product of S. miltiorrhiza. Although many publications described the regulation mechanism of SalB biosynthesis, few reports simultaneously focused on S. miltiorrhiza root development. For this study, an R2R3-MYB transcription factor gene (SmMYB52) was overexpressed and silenced, respectively, in S. miltiorrhiza sterile seedlings. We found that SmMYB52 significantly inhibited root growth and indole-3-acetic acid (IAA) accumulation, whereas it activated phenolic acid biosynthesis and the jasmonate acid (JA) signaling pathway. Quantitative real-time polymerase chain reaction (qRT-PCR) analyses revealed that SmMYB52 suppressed the transcription levels of key enzyme-encoding genes involved in the IAA biosynthetic pathway and activated key enzyme-encoding genes involved in the JA and phenolic acid biosynthesis pathways. In addition, yeast one-hybrid (Y1H) and dual-luciferase assay showed that SmMYB52 directly binds to and activates the promoters of several key enzyme genes for SalB biosynthesis, including SmTAT1, Sm4CL9, SmC4H1, and SmHPPR1, to promote the accumulation of SalB. This is the first report of a regulator that simultaneously affects root growth and the production of phenolic acids in S. miltiorrhiza.

6.
Mol Biol Evol ; 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34515790

RESUMO

Miniaturization has occurred in many animal lineages, including insects and vertebrates, as a widespread trend during animal evolution. Among Hymenoptera, miniaturization has taken place in some parasitoid wasp lineages independently, and may have contributed to the diversity of species. However, the genomic basis of miniaturization is little understood. Diverged approximately 200 million years ago, Telenomus wasps (Platygastridae) and Trichogramma wasps (Chalcidoidea) have both evolved to a highly reduced body size independently, representing a paradigmatic example of convergent evolution. Here we report a high-quality chromosomal genome of Telenomus remus, a promising candidate for controlling Spodoptera frugiperda, a notorious pest that has recently caused severe crop damage. The T. remus genome (129 megabases) is characterized by a low density of repetitive sequence and a reduction of intron length, resulting in the shrinkage of genome size. We show that hundreds of genes evolved faster in two miniaturized parasitoids Trichogramma pretiosum and T. remus. Among them, 38 genes exhibit extremely accelerated evolutionary rates in these miniaturized wasps, possessing diverse functions in eye and wing development as well as cell size control. These genes also highlight potential roles in body size regulation. In sum, our analyses uncover a set of genes with accelerated evolutionary rates in T. pretiosum and T. remus, which might be responsible for their convergent adaptations to miniaturization, and thus expand our understanding on the evolutionary basis of miniaturization. Additionally, the genome of T. remus represents the first genome resource of superfamily Platygastroidea, and will facilitate future studies of Hymenoptera evolution and pest control.

7.
Plant Dis ; 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34260283

RESUMO

Wheat powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a destructive disease seriously threatening yield and quality of common wheat (Triticum aestivum L., 2n=6x=42, AABBDD). Characterization of resistance genes against powdery mildew is useful in parental selection and for developing disease resistant cultivars. Chinese wheat breeding line KN0816 has superior agronomic performance and resistance to powdery mildew at all growth stages. Genetic analysis using populations of KN0816 crossed with different susceptible parents indicated that a single dominant gene, tentatively designated PmKN0816, conferred seedling resistance to different Bgt isolates. Using a bulked segregant analysis (BSA), PmKN0816 was mapped to the Pm6 interval on chromosome arm 2BL using polymorphic markers linked to the catalogued genes Pm6, Pm52, and Pm64, and flanked by markers CISSR02g-6 and CIT02g-2 both with genetic distances of 0.7 cM. Analysis of closely linked molecular markers indicated that the marker alleles of PmKN0816 differed from those of other powdery mildew resistance genes on 2BL, including Pm6, Pm33, Pm51, Pm64, and PmQ. Based on the genetic and physical locations and response pattern to different Bgt isolates, PmKN0816 is most likely a new powdery mildew resistance gene and confers effective resistance to all the 14 tested Bgt isolates. In view of the elite agronomic performance of KN0816 combined with the resistance, PmKN0816 is expected to become a valuable resistance gene in wheat breeding. To transfer PmKN0816 to different genetic backgrounds using marker-assisted selection (MAS), closely linked markers of PmKN0816 were evaluated and four of them (CIT02g-2, CISSR02g-6, CIT02g-10, and CIT02g-17) were confirmed to be applicable for MAS in different genetic backgrounds.

8.
Mol Ecol Resour ; 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34228883

RESUMO

The rice leaffolder Cnaphalocrocis exigua (Crambidae, Lepidoptera) is an important agricultural pest that damages rice crops and other members of related grass families. C. exigua exhibits a very similar morphological phenotype and feeding behaviour to C. medinalis, another species of rice leaffolder whose genome was recently reported. However, genomic information for C. exigua remains extremely limited. Here, we used a hybrid strategy combining different sequencing technologies, including Illumina, PacBio, 10× Genomics, and Hi-C scaffolding, to generate a high-quality chromosome-level genome assembly of C. exigua. We initially obtained a 798.8 Mb assembly with a contig N50 size of 2.9 Mb, and the N50 size was subsequently increased to 25.7 Mb using Hi-C technology to anchor 1413 scaffolds to 32 chromosomes. We detected a total of 97.7% Benchmarking Universal Single-Copy Orthologues (BUSCO) in the genome assembly, which was comprised of ~52% repetitive sequence and annotated 14,922 protein-coding genes. Of note, the Z and W sex chromosomes were assembled and identified. A comparative genomic analysis demonstrated that despite the high synteny observed between the two rice leaffolders, the species have distinct genomic features associated with expansion and contraction of gene families and selection pressure. In summary, our chromosome-level genome assembly and comparative genomic analysis of C. exigua provide novel insights into the evolution and ecology of this rice insect pests and offer useful information for pest control.

9.
ACS Nano ; 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34114794

RESUMO

Plasmonic nanoparticles are ideal candidates for hot-electron-assisted applications, but their narrow resonance region and limited hotspot number hindered the energy utilization of broadband solar energy. Inspired by tree branches, we designed and chemically synthesized silver fractals, which enable self-constructed hotspots and multiple plasmonic resonances, extending the broadband generation of hot electrons for better matching with the solar radiation spectrum. We directly revealed the plasmonic origin, the spatial distribution, and the decay dynamics of hot electrons on the single-particle level by using ab initio simulation, dark-field spectroscopy, pump-probe measurements, and electron energy loss spectroscopy. Our results show that fractals with acute tips and narrow gaps can support broadband resonances (400-1100 nm) and a large number of randomly distributed hotspots, which can provide unpolarized enhanced near field and promote hot electron generation. As a proof-of-concept, hot-electron-triggered dimerization of p-nitropthiophenol and hydrogen production are investigated under various irradiations, and the promoted hot electron generation on fractals was confirmed with significantly improved efficiency.

10.
Plant Dis ; 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34129353

RESUMO

Powdery mildew and leaf rust, caused by Blumeria graminis f. sp. tritici (Bgt) and Puccinia triticina (Pt), respectively, are widespread diseases of wheat worldwide. Utilizing resistant cultivars is considered as the most economical, environmental-friendly, and effective method to control these diseases. In the present study, a collection of 2,978 wheat accessions consisting of 1,394 advanced breeding lines, 1,078 Chinese cultivars, 291 introduced cultivars, 132 lines containing alien chromosomes, and 83 landraces was tested for reactions to powdery mildew and leaf rust. The results indicated that 659 (22.1%) wheat accessions were highly resistant to a widely prevalent Bgt isolate, E09, at the seedling stage, and 390 were consistently resistant to the mixture of Bgt isolates at the adult-plant stage. Meanwhile, 63 (2.1%) accessions were highly resistant to leaf rust at the adult-plant stage, of which 54 were resistant to a predominant and highly virulent Pt race, THTT, at the seedling stage. Notably, 17 accessions were resistant to both powdery mildew and leaf rust. To detect known genes for resistance to powdery mildew and leaf rust, these accessions were tested with gene-specific or tightly linked markers for seven Pm genes (Pm2, Pm4, Pm5, Pm6, Pm8, Pm21, and Pm24) and ten Lr genes (Lr1, Lr9, Lr10, Lr19, Lr20, Lr24, Lr26, Lr34, Lr37, and Lr46). Of the 659 powdery mildew-resistant accessions, 328 might carry single Pm genes and 191 carry combined Pm genes. Pm2 was detected at the highest frequency of 59.6%, followed by Pm8, Pm6, Pm21, Pm4, and Pm5, while Pm24 was not detected. Besides, 139 accessions might contain unknown Pm genes different from those tested in this study. In the 63 accessions resistant leaf rust, four Lr genes (Lr1, Lr10, Lr26, and Lr34) were detected in 41 accessions either singly or in combination, while six genes (Lr9, Lr19, Lr20, Lr24, Lr37, and Lr46) were not detected. Twenty-two accessions might contain unknown Lr genes different from those tested in this study. This study not only provided important information for rationally distributing resistance genes in wheat breeding programs, but also identified resistant germplasm that might have novel genes to enrich the diversity of resistance sources.

11.
Nat Plants ; 7(6): 774-786, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34045708

RESUMO

Increasing crop production is necessary to feed the world's expanding population, and crop breeders often utilize genetic variations to improve crop yield and quality. However, the narrow diversity of the wheat D genome seriously restricts its selective breeding. A practical solution is to exploit the genomic variations of Aegilops tauschii via introgression. Here, we established a rapid introgression platform for transferring the overall genetic variations of A. tauschii to elite wheats, thereby enriching the wheat germplasm pool. To accelerate the process, we assembled four new reference genomes, resequenced 278 accessions of A. tauschii and constructed the variation landscape of this wheat progenitor species. Genome comparisons highlighted diverse functional genes or novel haplotypes with potential applications in wheat improvement. We constructed the core germplasm of A. tauschii, including 85 accessions covering more than 99% of the species' overall genetic variations. This was crossed with elite wheat cultivars to generate an A. tauschii-wheat synthetic octoploid wheat (A-WSOW) pool. Laboratory and field analysis with two examples of the introgression lines confirmed its great potential for wheat breeding. Our high-quality reference genomes, genomic variation landscape of A. tauschii and the A-WSOW pool provide valuable resources to facilitate gene discovery and breeding in wheat.


Assuntos
Aegilops/genética , Introgressão Genética , Genoma de Planta , Melhoramento Vegetal/métodos , Triticum/genética , Elementos de DNA Transponíveis , Genética Populacional , Família Multigênica/genética , Filogenia , Proteínas de Plantas/genética , Poliploidia , Locos de Características Quantitativas , Sementes/genética , Sementes/crescimento & desenvolvimento
12.
Plant Dis ; 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33881917

RESUMO

Wheat powdery mildew is a devastating disease that seriously threatens yield worldwide. Utilization of host resistance is considered an effective strategy to minimize powdery mildew damage. Pm21, PmV, and Pm12 confer broad-spectrum resistance to wheat powdery mildew in China, of which Pm21 and PmV are allelic genes derived from the 6VS chromosome of Dasypyrum villosum, and Pm12 is derived from the 6SS chromosome of Aegilops speltoides and most likely orthologous to the former two genes. To accurately and efficiently transfer and pyramid these genes using marker-assisted selection (MAS), distinctive single nucleotide polymorphisms (SNPs) among the exon sequences of Pm21, PmV, and Pm12 and their homologous sequences in the common wheat genome were identified and used for developing diagnostic Kompetitive Allele-Specific PCR (KASP) markers. The markers were validated in different genotypes including transgenic vectors, transgenic lines, translocation lines, resistance stocks with documented Pm genes, and in multiple susceptible cultivars without Pm genes. As a result, we initially developed a KASP marker that can simultaneously diagnose Pm21, Pm12, and PmV. Subsequently, we obtained a highly diagnostic KASP marker for each of the three genes that could distinguish among the three genes and also accurately distinguish them from other resistant stocks with documented Pm genes and from multiple susceptible genotypes. Compared with previously reported markers, the highly diagnostic KASP markers developed in this study have the advantages of low cost, easy assay, accuracy, and potentially high throughput for MAS.

13.
Phys Rev Lett ; 126(11): 117402, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33798377

RESUMO

Bound states in the continuum (BICs) confine resonances embedded in a continuous spectrum by eliminating radiation loss. Merging multiple BICs provides a promising approach to further reduce the scattering losses caused by fabrication imperfections. However, to date, BIC merging has been limited to only the Γ point, which constrains potential application scenarios such as beam steering and directional vector beams. Here, we propose a new scheme to construct merging BICs at almost an arbitrary point in reciprocal space. Our approach utilizes the topological features of BICs on photonic crystal slabs, and we merge a Friedrich-Wintgen BIC and an accidental BIC. The Q factors of the resulting merging BIC are enhanced for a broad wave vector range compared with both the original Friedrich-Wintgen BIC and the accidental BIC. Since Friedrich-Wintgen BICs and accidental BICs are quite common in the band structure, our proposal provides a general approach to realize off-Γ merging BICs with superhigh Q factors that can substantially enhance nonlinear and quantum effects and boost the performance of on-chip photonic devices.

14.
Nanoscale ; 13(7): 4269-4277, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33595014

RESUMO

By virtue of its high throughput multiplex detection capability, superior read-out sensitivity, and tiny analyte consumption, an optically enhanced protein microarray assay has been developed as a promising diagnostic tool for various applications, ranging from the field of pharmacology to diagnostics. However, so far, the development of an optically enhanced protein microarray (OEPM) toward widespread commercial availability is mainly hampered by insufficient detection reproducibility. Here, we develop an OEPM platform with an order of magnitude optical enhancement induced by the interference effect. High assay reproducibility of the OEPM is achieved by optimizing the protein immobilization schemes, linking to the surface energy of the substrate, surfactant-tuned wetting ability, and the washing and drying dynamics. As a result, smearing-free and uniform spot arrays with a coefficient of variation less than 7% can be achieved. Furthermore, we demonstrate the assay performance of the OEPM by detecting five biomarkers, showing an order of magnitude higher sensitivity, many-fold higher throughput, and 10 times less analyte consumption than those of the commercial enzyme-linked immunosorbent assay kits. Our results provide new insight for improving the reproducibility of OEPMs toward practical and commercial diagnostic assays.


Assuntos
Análise Serial de Proteínas , Proteínas , Ensaio de Imunoadsorção Enzimática , Imunoensaio , Reprodutibilidade dos Testes
15.
Nanoscale ; 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33605947

RESUMO

Achieving strong coupling between emitters and cavity photons holds an important position in the light-matter interaction due to its applications such as polariton lasing, all-optical switches, and quantum information processing. However, room-temperature polaritonic devices with subwavelength dimensions based on strong light-matter coupling are difficult to realize using traditional emitter-cavity coupled systems. In recent years, coupled systems constructed from plasmonic nanostructures and transition metal dichalcogenides (TMDs) have shown their potential in achieving room-temperature strong coupling and robustness in the nanofabrication processes. This minireview presents the recent progress in strong plasmon-exciton coupling in such plasmonic-TMD hybrid structures. Differing from a broader scope of strong coupling, we focus on the plasmon-exciton coupling between excitons in TMDs and plasmons in single nanoparticles, nanoparticle-over-mirrors, and plasmonic arrays. In addition, we discuss the future perspectives on the strong plasmon-exciton coupling at few-excitons level and the nonlinear response of these hybrid structures in the strong coupling regime.

16.
Nanoscale ; 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33605960

RESUMO

Photothermal utilization is an important approach for sustaining global ecological balance. Due to the enhancement of light absorption through surface plasmon resonance, silver or gold nanostructures can be used as efficient photothermal heat sources in visible and near-infrared regions. Herein, a heat-trapping system of self-assembled gold nanoislands with a thin Al2O3 layer is designed to significantly enhance the photothermal effect, which can contribute to a fast crystal transformation. Compared with pure gold nanoislands, an approximately 10-fold enhancement of the photothermal conversion efficiency is observed by using the heat-trapping layer, which results from enhanced light absorption and efficient heat utilization. With the heat-trapping layer, a relatively high and stable photothermal conversion efficiency is realized even at low temperature, and the thermal stability of the plasmonic nanostructure is also observed to improve, especially for silver nanoislands used in air. These results provide a strong additional support for the further development of photothermal applications and offer an efficient pathway for the thermal manipulation of plasmons at the nanoscale.

17.
Plant Dis ; 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33630690

RESUMO

Wheat powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a devastating disease threatening yield and quality. Host resistance is considered the most effective and preferred means to control this disease. Wheat landrace Duanganmang (DGM) showed high resistance or near immunity to Bgt mixture from Henan province, China. DGM was crossed with highly susceptible Chinese wheat landrace Huixianhong (HXH) and cultivar Shimai 15 (SM15) to produce genetic populations. The resistance of DGM to Bgt isolate E09 was shown to be controlled by a single dominant Mendelian factor, tentatively designated PmDGM. Marker analysis and 55K SNP (single nucleotide polymorphism) array scanning showed that this gene was positioned in the Pm5 interval (2.4 cM or 1.61 Mb) flanked by Xhenu099 and Xmp1158 in the Chinese Spring reference genome. Homology-based cloning and sequence analysis demonstrated that DGM has the identical NLR gene (Pm5e) and RXL gene reported in Fuzhuang 30 (FZ30) conferring and modifying the powdery mildew resistance, respectively. However, based on the different reaction patterns to the Bgt isolate B15 between DGM and FZ30, we speculate that DGM may have two tightly linked genes that could not be separated in the current mapping population, one is PmDGM and the other is Pm5e. Hence, this study provides a valuable resistance resource for improvement of powdery mildew resistance.

18.
Plant Dis ; : PDIS10202296RE, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33417497

RESUMO

Powdery mildew, caused by fungal pathogen Blumeria graminis f. sp. tritici, is an agronomically important and widespread wheat disease causing severe yield losses. Deployment of broad-spectrum disease resistance genes is the preferred strategy to prevent this pathogen. Chinese wheat landrace Honghuaxiaomai (HHXM) was resistant to all 23 tested B. graminis f. sp. tritici isolates at the seedling stage. The F1, F2, and F2:3 progenies derived from the cross HHXM × Yangmai 158 were used in this study, and genetic analysis revealed that a single dominant gene, designated PmHHXM, conferred resistance to B. graminis f. sp. tritici isolate E09. Bulked segregant analysis and molecular mapping initially located PmHHXM to the distal region of chromosome 4AL. To fine map PmHHXM, we identified two critical recombinants from 592 F2 plants and delimited PmHHXM to a 0.18-cM Xkasp475200 to Xhnu552 interval covering 1.77 Mb, in which a number of disease resistance-related gene clusters were annotated. Comparative mapping of this interval revealed a perturbed synteny among Triticeae species. This study reports the new powdery mildew resistance gene PmHHXM, which seems different from three known quantitative trait loci/genes identified on chromosome 4AL and has significant values for further genetic improvement. Analysis of the polymorphisms of 13 cosegregating markers between HHXM and 170 modern wheat cultivars indicates that Xhnu227 and Xsts478700 developed here are ideal for marker-assisted introgression of this locus in wheat breeding.

19.
Nanoscale ; 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33439191

RESUMO

A plasmonic waveguide is a fundamental building block for high speed, large data transmission capacity, low energy consumption optical communication and sensing. Controllable fabrication and simultaneous optimization of propagation loss and coupling efficiency with free space light are essential for the realization of ultra-compact passive and active plasmonic components. Here, we proposed gold nanostrips on a silicon-on-insulator wafer as plasmonic waveguides and first demonstrated the direct free-space light coupling and end-scattering detection of the top-down fabricated plasmonic waveguide. The scattering intensity from the terminal of a 6 µm long nanostrip can be improved experimentally over 34 times larger than that on the silica substrate. The controllable fabrication process renders the gold nanostrip on a silicon-on-insulator substrate a promising building block for ultracompact, monolithic integration and CMOS-compatible plasmonic devices in optical communication and sensing.

20.
Nanoscale ; 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33403380

RESUMO

Structural colors, which originate from the interactions between light and nanometer-scale structured materials, have the advantages of durability and environmentally friendly display compared with pigments and dyes. A large color gamut, high-speed, electrically-switching reflective structural color display is critical to dynamically tunable reflective structural color devices. Here, we report a theoretical design of an electrically switching reflective structural color display device with a large color gamut (∼157% sRGB, standard red green blue) and high speed (>10 MHz). Benefiting from the electric-switchable Epsilon-Near-Zero material and 1D dielectric grating with guided-mode resonance, the reflective display device can be electrically turned on or turned off by switching between a narrow band reflector and a transparent film. This design provides a promising solution towards reflective color displays, optical switches, spatial light modulators and so on.

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