Kernel weight(KW), together with kernel number per unit area, determines yield of cereal crops. Here,two barley recombinant inbred lines(RILs) populations with a shared parent were used to identify loci controlling KW...Kernel weight(KW), together with kernel number per unit area, determines yield of cereal crops. Here,two barley recombinant inbred lines(RILs) populations with a shared parent were used to identify loci controlling KW. One is Baudin/AWCS276(BA) for which a linkage map was available. Several largeeffect QTL controlling KW were detected in this population. Another is Morex/AWCS276(MA). A linkage map with 5273 makers formed 1454 clusters, was constructed by the genotyping by sequence(GBS) data of 201 RILs from this population. A single marker was selected to represent each of the clusters and the linkage map constructed with these markers covers a total length of 1022.4 c M with an average interval of approximately 0.7 cM between loci. Three of the large-effect loci controlling KW(located on 2 HL, 6 HL,and 7 HL, respectively) identified from the BA population were also detected in the MA population under different environments. The locus on 6 HL was detected in each of the experiments conducted for both populations thus was selected for developing near isogenic lines(NILs). Apart from KW, the two isolines for each pair of the putative NILs obtained showed no significant difference for any of the morphological characteristics assessed. The average difference in KW between the isolines for all the NILs obtained was about 15% based on assessments under both glasshouse and field conditions. Taken advantage that high quality genome assemblies for both Morex and AWCS276 are available, we identified candidate genes underlying two of the three loci based on an orthologous analysis. The NILs developed and the candidate genes identified in this study should facilitate the cloning and functional analysis of genes regulating KW in barley.展开更多
Productive tiller number(PTN)is a pivotal trait that significantly influences wheat grain yield.To date,there have been limited reports on the cloning of genes that regulate PTN in wheat.The quantitative trait locus(Q...Productive tiller number(PTN)is a pivotal trait that significantly influences wheat grain yield.To date,there have been limited reports on the cloning of genes that regulate PTN in wheat.The quantitative trait locus(QTL)QPtn.sau-4B,associated with PTN,was previously mapped between the markers KASP-1 and KASP-3 on the chromosome 4B.Here,utilizing 12 newly developed markers and phenotypic data of PTN from recombinants identified within this interval,QPtn.sau-4B was further fine-mapped to a 2.58 Mb interval on wheat chromosome arm 4BS.Within this interval,we identified 14 genes with high-confidence and 32 genes with low-confidence.A 0.17 Mb deletion fragment contained TraesCS4B03G0092600 and TraesCS4B03G0093100,which were assigned as candidate genes for QPtn.sau-4B.Additionally,QPtn.sau-4B had potential to enhance both PTN and grain yield in wheat.Cloning this locus would support the development of wheat cultivars with increased grain yield.展开更多
Wheat is an important cereal crop used to produce diverse and popular food worldwide because of its high grain yield(GY)and grain protein content(GPC).However,GY and GPC are usually negatively correlated.We previously...Wheat is an important cereal crop used to produce diverse and popular food worldwide because of its high grain yield(GY)and grain protein content(GPC).However,GY and GPC are usually negatively correlated.We previously reported that favorable alleles of the wheat domestication gene Q can synchronously increase GY and GPC,but the underlying mechanisms remain largely unknown.In this study,we investigate the regulatory network involving Q associated with GY and GPC in young grains through DNA affinity purification sequencing and transcriptome sequencing analyses,electrophoretic mobility shift and dualluciferase assays,and transgenic approaches.Three Q-binding motifs,namely TTAAGG,AAACA[A/T]A,and GTAC[T/G]A,are identified.Notably,genes related to photosynthesis or carbon and nitrogen metabolism are enriched and regulated by Q.Moreover,Q is revealed to bind directly to its own gene and the glutamine synthetase gene GSr-4D to increase expression,thereby influencing nitrogen assimilation during the grain filling stage and increasing GPC.Considered together,our findings provide molecular evidence of the positive regulatory effects of Q on wheat GY and GPC.展开更多
Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synt...Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synthase 2a(SS2a)is a key enzyme in amylopectin biosynthesis that has significant effects on starch structure and properties.In this study,we identified an ss2a null mutant(M3-1413)with a single base mutation from an ethyl methane sulfonate(EMS)-mutagenized population of barley.The mutation was located at the 3'end of the first intron of the RNA splicing receptor(AG)site,and resulted in abnormal RNA splicing and two abnormal transcripts of ss2a,which caused the inactivation of the SS2a gene.The starch structure and properties were significantly altered in the mutant,with M3-1413 containing lower total starch and higher amylose and resistant starch levels.This study sheds light on the effect of barley ss2a null mutations on starch properties and will help to guide new applications of barley starch in the development of nutritious food products.展开更多
Grain number per spikelet (GNS) is a key determinant of grain yield in wheat.A recombinant inbred line population comprising 300 lines was developed from a cross between a high GNS variety H461 and Chinese Spring from...Grain number per spikelet (GNS) is a key determinant of grain yield in wheat.A recombinant inbred line population comprising 300 lines was developed from a cross between a high GNS variety H461 and Chinese Spring from which the reference genome assembly of bread wheat was obtained.Both parents and the recombinant inbred lines were genotyped using the wheat 55K single nucleotide polymorphism(SNP) array.A high-density genetic map containing 21,197 SNPs was obtained.These markers covered each of the 21 chromosomes with a total linkage distance of 3792.71 c M.Locations of these markers in this linkage map were highly consistent with their physical locations in the genome assembly of Chinese Spring.The two parents and the whole RIL population were assessed for GNS in two consecutive years at two different locations.Based on multi-environment phenotype data and best liner unbiased prediction values,three quantitative trait loci (QTL) for GNS were identified.One of them located on chromosomes 2B and the other two on 2D.Phenotypic variation explained by these loci varied from 3.07%to26.57%.One of these QTL,QGns.sicau-2D-2,was identified in each of all trials conducted.Based on the best linear unbiased prediction values,this locus explained 19.59%–26.57%of phenotypic variation.A KASP(Kompetitive Allele-Specific PCR) marker closely linked with this locus was generated and used to validate the effects of this locus in three different genetic backgrounds.The identified QTL and the KASP marker developed for it will be highly valuable in fine-mapping the locus and in exploiting it for markerassisted selection in wheat breeding programs.展开更多
Stripe rust, caused by Puccinia striiformis f. sp. tritici(Pst), threatens wheat production worldwide, and resistant varieties tend to become susceptible after a period of cultivation owing to the variation of pathoge...Stripe rust, caused by Puccinia striiformis f. sp. tritici(Pst), threatens wheat production worldwide, and resistant varieties tend to become susceptible after a period of cultivation owing to the variation of pathogen races. In this study, a new resistance gene against Pst race CYR34 was identified and predicted using the descendants of a cross between AS1676, a highly resistant Chinese landrace, and Avocet S, a susceptible cultivar. From a heterozygous plant from a F7recombinant inbred line(RIL) population lacking the Yr18 gene, a near-isogenic line(NIL) population was developed to map the resistance gene. An allstage resistance gene, YrAS1676, was identified on chromosome arm 1AL via bulked-segregant exomecapture sequencing. By analyzing a large NIL population consisting of 6537 plants, the gene was further mapped to the marker interval between KA1A_485.36 and KA1A_490.13, spanning 485.36–490.13 Mb on1AL. A total of 66 annotated genes have been reported in this region. To characterize and predict the candidate gene(s), an RNA-seq was performed using NIL-R and NIL-S seedlings 3 days after CYR34 inoculation. Compared to NIL-S plants, NIL-R plants showed stronger immune reaction and higher expression levels of genes encoding pathogenesis-associated proteins. These differences may help to explain why NIL-R plants were more resistant to Pst race CYR34 than NIL-S plants. By combining fine-mapping and transcriptome sequencing, a calcium-dependent protein kinase gene was finally predicted as the potential candidate gene of YrAS1676. This gene contained a single-nucleotide polymorphism. The candidate gene was more highly expressed in NIL-R than in NIL-S plants. In field experiments with Pst challenge,the YrAS1676 genotype showed mitigation of disease damage and yield loss without adverse effects on tested agronomic traits. These results suggest that YrAS1676 has potential use in wheat stripe rust resistance breeding.展开更多
Tiller angle(TA)strongly influences plant architecture and grain yield in cereals.However,the genetic basis of TA in wheat is largely unknown.We identified three TA-related quantitative trait loci(QTL).One of them was...Tiller angle(TA)strongly influences plant architecture and grain yield in cereals.However,the genetic basis of TA in wheat is largely unknown.We identified three TA-related quantitative trait loci(QTL).One of them was QTa.sau-2 B-769,a major QTL localized on chromosome arm 2 BL.QTa.sau-2 B-769 was detected in seven environments,explaining 18.1%–51.1%of phenotypic variance.We developed a linked Kompetitive Allele-Specific Polymerase chain reaction(KASP)marker,KASP-AX-108792274,to further validate this locus in three additional populations in multiple environments.QTa.sau-2 B-769 increased TA by up to 24.9%in these populations.There were significant and positive correlations between TA and flag leaf angle(FLANG).However,TA was not correlated with plant height or anthesis date,suggesting that expression of QTa.sau-2 B-769 is independent of vernalization.Traes CS2 B01 G583800,a gene known to be involved in leaf angle regulation,was identified as the most likely candidate gene for QTa.sau-2 B-769.These results enrich our understanding of the mechanisms regulating wheat TA at maturity and may support precise mapping and cloning of gene(s)underlying QTa.sau-2 B-769.展开更多
Stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),is one of the most important diseases threatening the yield and stability of wheat production in China and many other countries.Identification and utilizati...Stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),is one of the most important diseases threatening the yield and stability of wheat production in China and many other countries.Identification and utilization of new genes for durable stripe rust resistance are important for ongoing control of this disease.The objectives of this study were to identify quantitative trait loci(QTL)associated with adult-plant stripe rust resistance in the Chinese wheat landrace Yibinzhuermai(YBZR)and to provide wheat breeders with new sources of potentially durable resistance.A total of 117 recombinant inbred lines(RILs)(F5:8)derived from a cross between YBZR and highly susceptible cultivar Taichung 29(TC29)were assessed for stripe rust severity in field experiments at Wenjiang in 2016 and 2017 and Chongzhou in 2016,2017,2018,and 2019 in Sichuan following inoculation with a mixture of current Pst races.The RILs were genotyped using the Wheat55K single nucleotide polymorphism(SNP)array.Three QTL were identified on chromosome arms 6AL,5BL and 7DS.QYr.YBZR-6AL and QYr.YBZR-7DS conferred major effects in all field environments,explaining 10.6%to 14.7%and 11.5%to 21.2%of phenotypic variation,respectively.The QTL on 5BL and 7DS likely correspond to previously known QTL,whereas QYr.YBZR-6AL is probably novel.Haplotype analysis revealed that the resistance allele at QYr.YBZR-6AL was present in 2.8%of 324 Chinese wheat landraces.SNP markers closely linked with QYr.YBZR-6AL were converted to kompetitive allele-specific PCR markers and validated in the RIL population and a subset of 92 wheat cultivars.QYr.YBZR-6AL and its markers should be useful in breeding programs to improve the level and durability of stripe rust resistance.展开更多
Stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease in wheat worldwide.Discovering and characterizing new resistance genes/QTL is crucial for wheat breeding programs.In this study,we ...Stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease in wheat worldwide.Discovering and characterizing new resistance genes/QTL is crucial for wheat breeding programs.In this study,we fine-mapped and characterized a stripe rust resistance gene,YRAYH,on chromosome arm 5BL in the Chinese wheat landrace Anyuehong(AYH).Evaluations of stripe rust response to prevalent Chinese Pst races in near-isogenic lines derived from a cross of Anyuehong and Taichung 29 showed that YrAYH conferred a high level of resistance at all growth stages.Fine mapping using a large segregating population of 9748 plants,narrowed the YRAYH locus to a 3.7 Mb interval on chromosome arm 5BL that included 61 annotated genes.Transcriptome analysis of two NIL pairs identified 64 upregulated differentially expressed genes(DEGs)in the resistant NILs(NILs-R).Annotations indicated that many of these genes have roles in plant disease resistance pathways.Through a combined approach of fine-mapping and transcriptome sequencing,we identified a serine/threonine-protein kinase SRPK as a candidate gene underlying YrAYH.A unique 25 bp insertion was identified in the NILs-R compared to the NILs-S and previously published wheat genomes.An InDel marker was developed and co-segregated with YrAYH.Agronomic trait evaluation of the NILs suggested that YrAYH not only reduces the impact of stripe rust but was also associated with a gene that increases plant height and spike length.展开更多
Genomic DNA and cDNA sequences of an isoamylase gene were isolated and characterized from the rye genome. The full-lengths of the rye isoamylase gene are 7351 bp for genomic DNA and 2364 bp for cDNA. There are 18 exon...Genomic DNA and cDNA sequences of an isoamylase gene were isolated and characterized from the rye genome. The full-lengths of the rye isoamylase gene are 7351 bp for genomic DNA and 2364 bp for cDNA. There are 18 exons and 17 introns in the genomic sequence, which shares a similar organization with homologous genes from Aegilops tauschii, maize, rice and Arabidopsis. Exon regions of rye and other plant isoamylase genes are more conserved than the introns. High sequence similarity(>95%) was observed in mature proteins of isoamylase genes originating from rye, Ae. tauschii, wheat and barley. The transcript profile revealed that rye isoamylase is mainly expressed in the seed endosperm with a maximum level at the middle developmental stage(15 DPA). A phylogenetic tree based on the deduced aa sequences of mature proteins from rye and other plant isoamylases indicated that rye isoamylase is more closely related to Ae. tauschii wDBE1 and wheat iso1. This is the first report on identification and characterization of the isoamylase gene from rye, making it possible to explore the roles of this enzyme for amylopectin development in rye and triticale.展开更多
The Brassicaceae species Braya humilis shows broad adaptation to different climatic zones and latitudes. However, the molecular adaptation mechanism of B. humilis is poorly understood. In China, B. humilis is mainly d...The Brassicaceae species Braya humilis shows broad adaptation to different climatic zones and latitudes. However, the molecular adaptation mechanism of B. humilis is poorly understood. In China, B. humilis is mainly distributed on the QinghaiTibetan Plateau(QTP) and in the adjacent arid region. Previous transcriptome analysis of B. humilis has revealed that 39 salt and osmotic stress response genes are subjected to purifying selection during its speciation. To further explore the adaptation mechanism of B. humilis to an arid environment, OrthoMCL program was employed in this study and 6,268 pairs of orthologous gene pairs with high confidence were obtained between B. humilis and Arabidopsis thaliana. A comparative evolutionary analysis based on nonsynonymous to synonymous substitution ratio(Ka/Ks) was then conducted. There were 64 pairs exhibiting a Ka/Ks ratio more than 0.5 and among which, three instrumental candidate genes, T20487,T22576, and T23757, were identified with strong selection signatures(Ka/Ks >1). The corresponding A. thaliana orthologs are double-stranded RNA-binding domain protein, MADS-box family protein, and NADH-dehydrogenase subunit6, which is encoded by mitochondria genome. This report not only demonstrates the adaptation contribution of fast evolving nuclear genes, but also highlights the potential adaptive value of mitochondria gene to the speciation and adaptation of B. humilis toward the extreme environment in an arid region.展开更多
Human vision–inspired neuromorphic devices have integrated architectures that combine sensing,computing,and storage functions,which can fundamentally avoid the energy waste caused by frequent data movement in the cur...Human vision–inspired neuromorphic devices have integrated architectures that combine sensing,computing,and storage functions,which can fundamentally avoid the energy waste caused by frequent data movement in the currently widely used von Neumann architecture,and have crucial application potential in advanced artificial intelligence chips that pursue low power consumption and low latency.However,previously reported visual neuromorphic devices either suffer complex floating gate,vertically stacked multilayer structures,or necessitate separated optical-sensing and synaptic units,realizing highly compact,nonvolatile optoelectronic response and continuously tunable conductivity within a sententious architecture remains a significant challenge.Here,we presented a low-cost exfoliation and transfer method combined with spin-coating to fabricate molybdenum disulfide(MoS_(2))/barium titanate(BaTiO_(3))heterostructured optoelectronic devices.Based on the ferroelectricity of BaTiO_(3)and the charge transport characteristics of MoS_(2),the hysteresis of ferroelectric polarization upon both electric and optical stimulation is successfully endowed with reliable resistance state switching abilities,showing the advantages of low bias voltage operation(±2 V)and distinct 16 conductance states under light pulse irradiation.Besides,the MoS_(2)/BaTiO_(3)device can be further used to emulate biological synaptic behavior and accomplish the transition from short-term memory(STM)to long-term memory(LTM).Notably,leveraging the dual characteristics of imaging and neuromorphic behavior,we constructed a multi-layer perceptron network integrating visual perception and image recognition,showing an accuracy of 97.6%in the Modified National Institute of Standards and Technology(MNIST)pattern recognition task.This work introduced a simple MoS_(2)/BaTiO_(3)heterojunction architecture device,offering integrated perception,storage,and computing capabilities,providing a new possibility for future compact neuromorphic computing devices.展开更多
Highly compact lasers with ultra-low threshold and single-mode continuous wave(CW)operation have been a long sought-after component for photonic integrated circuits(PICs).Photonic bound states in the continuum(BICs),d...Highly compact lasers with ultra-low threshold and single-mode continuous wave(CW)operation have been a long sought-after component for photonic integrated circuits(PICs).Photonic bound states in the continuum(BICs),due to their excellent ability of trapping light and enhancing light-matter interaction,have been investigated in lasing configurations combining various BIC cavities and optical gain materials.However,the realization of BIC laser with a highly compact size and an ultra-low CW threshold has remained elusive.We demonstrate room temperature CW BIC lasers in the 1310 nm O-band wavelength range,by fabricating a miniaturized BIC cavity in an InAs/GaAs epitaxial quantum dot(QD)gain membrane.By enabling effective trapping of both light and carriers in all three dimensions,ultra-low threshold of 12μW(0.052 kW cm^(-2))is achieved at room temperature.Single-mode lasing is also realized in cavities as small as only 5×5 unit cells(~2.5×2.5μm^(2) cavity size)with a mode volume of 1.16(λ/n)^(3).The maximum operation temperature reaches 70℃ with a characteristic temperature of T_(0)~93.9 K.With its advantages in terms of a small footprint,ultra-low power consumption,and adaptability for integration,the mini-BIC lasers offer a perspective light source for future PICs aimed at high-capacity optical communications,sensing and quantum information.展开更多
Optical microcavities have widely been employed to enhance either the optical excitation or the photon emission processes for boosting light-matter interactions at the nanoscale.When both the excitation and emission p...Optical microcavities have widely been employed to enhance either the optical excitation or the photon emission processes for boosting light-matter interactions at the nanoscale.When both the excitation and emission processes are simultaneously facilitated by the optical resonances provided by the microcavities,as referred to the dual-resonance condition in this article,the performances of many nanophotonic devices approach to the optima.In this work,we present versatile accessing of dual-resonance conditions in deterministically coupled quantum-dot(QD)-micropillars,which enables emission from neutral exciton(X)—charged exciton(CX)transition with improved single-photon purity.In addition,the rarely observed up-converted single-photon emission process is achieved under dual-resonance conditions.We further exploit the vectorial nature of the high-order cavity modes to significantly improve the excitation efficiency under the dual-resonance condition.The dual-resonance enhanced light-matter interactions in the quantum regime provide a viable path for developing integrated quantum photonic devices based on cavity quantum electrodynamics(QED)effect,e.g.,highly efficient quantum light sources and quantum logical gates.展开更多
During their co-evolution with herbivorous insects,plants have developed multiple defense strategies that resist pests,such as releasing a blend of herbivory-induced plant volatiles(HIPVs)that repel pests or recruit t...During their co-evolution with herbivorous insects,plants have developed multiple defense strategies that resist pests,such as releasing a blend of herbivory-induced plant volatiles(HIPVs)that repel pests or recruit their natural enemies.However,the responses of insects to HIPVs in maize(Zea mays L.) are not well understood.Here,we demonstrate that the Asian corn borer(ACB,Ostrinia furnacalis),a major insect pest of maize,shows a preference for maize pre-infested with ACB larvae rather than being repelled by these plants.Through combined transcriptomic and metabolomics analysis of ACB-infested maize seedlings,we identified two substances that explain this behavior:(E)-4,8-dimethylnona-1,3,7-triene(DMNT) and(3E,7E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene(TMTT).DMNT and TMTT attracted ACB larvae,and knocking out the maize genes responsible for their biosynthesis via gene editing impaired this attraction.External supplementation with DMNT/TMTT hampered the larvae's ability to locate pre-infested maize.These findings uncover a novel role for DMNT and TMTT in driving the behavior of ACB.Genetic modification of maize to make it less detectable by ACB might be an effective strategy for developing maize germplasm resistant to ACB and for managing this pest effectively in the field.展开更多
Self-assembled semiconductor quantum dots(QDs)are potentially scalable candidates for solid-state single-photon emitters which deterministically generate one single-photon per excitation.Such on-demand single-photon s...Self-assembled semiconductor quantum dots(QDs)are potentially scalable candidates for solid-state single-photon emitters which deterministically generate one single-photon per excitation.Such on-demand single-photon sources serve as one of the key elements in modern photonic quantum technologies[1].Until very recently,near-optimal QD single-photon sources with simultaneous high degree of brightness,single-photon purity and indistin-展开更多
The emerging hybrid integrated quantum photonics combines the advantages of different functional components into a single chip to meet the stringent requirements for quantum information processing.Despite the tremendo...The emerging hybrid integrated quantum photonics combines the advantages of different functional components into a single chip to meet the stringent requirements for quantum information processing.Despite the tremendous progress in hybrid integrations of III-V quantum emitters with silicon-based photonic circuits and superconducting single-photon detectors,on-chip optical excitations of quantum emitters via miniaturized lasers towards single-photon sources(SPSs)with low power consumptions,small device footprints,and excellent coherence properties is highly desirable yet illusive.In this work,we present realizations of bright semiconductor SPSs heterogeneously integrated with on-chip electrically-injected microlasers.Different from previous one-by-one transfer printing technique implemented in hybrid quantum dot(QD)photonic devices,multiple deterministically coupled QD-circular Bragg Grating(CBG)SPSs were integrated with electrically-injected micropillar lasers at one time via a potentially scalable transfer printing process assisted by the wide-field photoluminescence(PL)imaging technique.Optically pumped by electrically-injected microlasers,pure single photons are generated with a high-brightness of a count rate of 3.8 M/s and an extraction efficiency of 25.44%.Such a high-brightness is due to the enhancement by the cavity mode of the CBG,which is confirmed by a Purcell factor of 2.5.Our work provides a powerful tool for advancing hybrid integrated quantum photonics in general and boosts the developments for realizing highly-compact,energy-efficient and coherent SPSs in particular.展开更多
This paper deals with the existence of denumberable positive solutions to boundary value problems of delay differential equations with denumberable singularities on infinite intervals.By the fixed-point index theory a...This paper deals with the existence of denumberable positive solutions to boundary value problems of delay differential equations with denumberable singularities on infinite intervals.By the fixed-point index theory and a new fixed-point theorem in cones,the existence of denumberable positive solutions is obtained under some suitable growth conditions imposed on the nonlinear term.展开更多
基金supported by the National Natural Science Foundation of China(31771794)the National Key Research and Development Program of China(2017YFD0100900 and 2016YFD0101004)+1 种基金the Outstanding Youth Foundation of the Department of Science and Technology of Sichuan Province(2016JQ0040)the International Science&Technology Cooperation Program of the Bureau of Science and Technology of Chengdu China(2015DFA306002015-GH03-00008-HZ)。
文摘Kernel weight(KW), together with kernel number per unit area, determines yield of cereal crops. Here,two barley recombinant inbred lines(RILs) populations with a shared parent were used to identify loci controlling KW. One is Baudin/AWCS276(BA) for which a linkage map was available. Several largeeffect QTL controlling KW were detected in this population. Another is Morex/AWCS276(MA). A linkage map with 5273 makers formed 1454 clusters, was constructed by the genotyping by sequence(GBS) data of 201 RILs from this population. A single marker was selected to represent each of the clusters and the linkage map constructed with these markers covers a total length of 1022.4 c M with an average interval of approximately 0.7 cM between loci. Three of the large-effect loci controlling KW(located on 2 HL, 6 HL,and 7 HL, respectively) identified from the BA population were also detected in the MA population under different environments. The locus on 6 HL was detected in each of the experiments conducted for both populations thus was selected for developing near isogenic lines(NILs). Apart from KW, the two isolines for each pair of the putative NILs obtained showed no significant difference for any of the morphological characteristics assessed. The average difference in KW between the isolines for all the NILs obtained was about 15% based on assessments under both glasshouse and field conditions. Taken advantage that high quality genome assemblies for both Morex and AWCS276 are available, we identified candidate genes underlying two of the three loci based on an orthologous analysis. The NILs developed and the candidate genes identified in this study should facilitate the cloning and functional analysis of genes regulating KW in barley.
基金supported by National Key Research and Development Program of China(2023YFD1201900)National Nat-ural Science Foundation of China(32472078,31971937)+2 种基金Natural Science Foundation of Sichuan Province(2024NSFSC0312)Crop Characteristic Resources Creation and Utilization Key Laboratory of Sichuan Province(myzdsys24-01)the Key Laboratory of Exploitation and Study of Distinctive Plants in Education Department of Sichuan Province(TSZW2023ZB-10).
文摘Productive tiller number(PTN)is a pivotal trait that significantly influences wheat grain yield.To date,there have been limited reports on the cloning of genes that regulate PTN in wheat.The quantitative trait locus(QTL)QPtn.sau-4B,associated with PTN,was previously mapped between the markers KASP-1 and KASP-3 on the chromosome 4B.Here,utilizing 12 newly developed markers and phenotypic data of PTN from recombinants identified within this interval,QPtn.sau-4B was further fine-mapped to a 2.58 Mb interval on wheat chromosome arm 4BS.Within this interval,we identified 14 genes with high-confidence and 32 genes with low-confidence.A 0.17 Mb deletion fragment contained TraesCS4B03G0092600 and TraesCS4B03G0093100,which were assigned as candidate genes for QPtn.sau-4B.Additionally,QPtn.sau-4B had potential to enhance both PTN and grain yield in wheat.Cloning this locus would support the development of wheat cultivars with increased grain yield.
基金supported by the National Key Research and Development Program of China(2023YFD1200404)the Science and Technology Department of Sichuan Province(2024ZYD0160)the National Natural Science Foundation of China(32072054).
文摘Wheat is an important cereal crop used to produce diverse and popular food worldwide because of its high grain yield(GY)and grain protein content(GPC).However,GY and GPC are usually negatively correlated.We previously reported that favorable alleles of the wheat domestication gene Q can synchronously increase GY and GPC,but the underlying mechanisms remain largely unknown.In this study,we investigate the regulatory network involving Q associated with GY and GPC in young grains through DNA affinity purification sequencing and transcriptome sequencing analyses,electrophoretic mobility shift and dualluciferase assays,and transgenic approaches.Three Q-binding motifs,namely TTAAGG,AAACA[A/T]A,and GTAC[T/G]A,are identified.Notably,genes related to photosynthesis or carbon and nitrogen metabolism are enriched and regulated by Q.Moreover,Q is revealed to bind directly to its own gene and the glutamine synthetase gene GSr-4D to increase expression,thereby influencing nitrogen assimilation during the grain filling stage and increasing GPC.Considered together,our findings provide molecular evidence of the positive regulatory effects of Q on wheat GY and GPC.
基金supported by the Major Program of National Agricultural Science and Technology of China(NK20220607)the Sichuan Science and Technology Program,China(2023YFH0041)。
文摘Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synthase 2a(SS2a)is a key enzyme in amylopectin biosynthesis that has significant effects on starch structure and properties.In this study,we identified an ss2a null mutant(M3-1413)with a single base mutation from an ethyl methane sulfonate(EMS)-mutagenized population of barley.The mutation was located at the 3'end of the first intron of the RNA splicing receptor(AG)site,and resulted in abnormal RNA splicing and two abnormal transcripts of ss2a,which caused the inactivation of the SS2a gene.The starch structure and properties were significantly altered in the mutant,with M3-1413 containing lower total starch and higher amylose and resistant starch levels.This study sheds light on the effect of barley ss2a null mutations on starch properties and will help to guide new applications of barley starch in the development of nutritious food products.
基金supported by the National Natural Science Foundation of China (31771794)the National Key Research and Development Program of China (2016YFD0101004 and 2017YFD0100900)the International Science & Technology Cooperation Program of the Bureau of Science and Technology of Chengdu China (2015DFA306002015-GH03-00008-HZ)。
文摘Grain number per spikelet (GNS) is a key determinant of grain yield in wheat.A recombinant inbred line population comprising 300 lines was developed from a cross between a high GNS variety H461 and Chinese Spring from which the reference genome assembly of bread wheat was obtained.Both parents and the recombinant inbred lines were genotyped using the wheat 55K single nucleotide polymorphism(SNP) array.A high-density genetic map containing 21,197 SNPs was obtained.These markers covered each of the 21 chromosomes with a total linkage distance of 3792.71 c M.Locations of these markers in this linkage map were highly consistent with their physical locations in the genome assembly of Chinese Spring.The two parents and the whole RIL population were assessed for GNS in two consecutive years at two different locations.Based on multi-environment phenotype data and best liner unbiased prediction values,three quantitative trait loci (QTL) for GNS were identified.One of them located on chromosomes 2B and the other two on 2D.Phenotypic variation explained by these loci varied from 3.07%to26.57%.One of these QTL,QGns.sicau-2D-2,was identified in each of all trials conducted.Based on the best linear unbiased prediction values,this locus explained 19.59%–26.57%of phenotypic variation.A KASP(Kompetitive Allele-Specific PCR) marker closely linked with this locus was generated and used to validate the effects of this locus in three different genetic backgrounds.The identified QTL and the KASP marker developed for it will be highly valuable in fine-mapping the locus and in exploiting it for markerassisted selection in wheat breeding programs.
基金supported by the Major Program of National Agricultural Science and Technology of China (NK20220607)the National Natural Science Foundation of China (32272059 and31971883)the Science and Technology Department of Sichuan Province (2022ZDZX0014, 2021YFYZ0002, 2021YJ0297, and23NSFTD0045)。
文摘Stripe rust, caused by Puccinia striiformis f. sp. tritici(Pst), threatens wheat production worldwide, and resistant varieties tend to become susceptible after a period of cultivation owing to the variation of pathogen races. In this study, a new resistance gene against Pst race CYR34 was identified and predicted using the descendants of a cross between AS1676, a highly resistant Chinese landrace, and Avocet S, a susceptible cultivar. From a heterozygous plant from a F7recombinant inbred line(RIL) population lacking the Yr18 gene, a near-isogenic line(NIL) population was developed to map the resistance gene. An allstage resistance gene, YrAS1676, was identified on chromosome arm 1AL via bulked-segregant exomecapture sequencing. By analyzing a large NIL population consisting of 6537 plants, the gene was further mapped to the marker interval between KA1A_485.36 and KA1A_490.13, spanning 485.36–490.13 Mb on1AL. A total of 66 annotated genes have been reported in this region. To characterize and predict the candidate gene(s), an RNA-seq was performed using NIL-R and NIL-S seedlings 3 days after CYR34 inoculation. Compared to NIL-S plants, NIL-R plants showed stronger immune reaction and higher expression levels of genes encoding pathogenesis-associated proteins. These differences may help to explain why NIL-R plants were more resistant to Pst race CYR34 than NIL-S plants. By combining fine-mapping and transcriptome sequencing, a calcium-dependent protein kinase gene was finally predicted as the potential candidate gene of YrAS1676. This gene contained a single-nucleotide polymorphism. The candidate gene was more highly expressed in NIL-R than in NIL-S plants. In field experiments with Pst challenge,the YrAS1676 genotype showed mitigation of disease damage and yield loss without adverse effects on tested agronomic traits. These results suggest that YrAS1676 has potential use in wheat stripe rust resistance breeding.
基金supported by the National Natural Science Foundation of China(31971937 and 31970243)the International Science and Technology Cooperation and Exchanges Program of Science and Technology Department of Sichuan Province(2021YFH0083)+2 种基金the Applied Basic Research Programs of Science and Technology Department of Sichuan Province(2021YJ0503and 2020YJ0140)the Key Projects of Scientific and Technological Activities for Overseas Students of Sichuan Provincethe Basic Research Project of Science and Technology Plan of Guizhou Province(ZK2021 general 131)。
文摘Tiller angle(TA)strongly influences plant architecture and grain yield in cereals.However,the genetic basis of TA in wheat is largely unknown.We identified three TA-related quantitative trait loci(QTL).One of them was QTa.sau-2 B-769,a major QTL localized on chromosome arm 2 BL.QTa.sau-2 B-769 was detected in seven environments,explaining 18.1%–51.1%of phenotypic variance.We developed a linked Kompetitive Allele-Specific Polymerase chain reaction(KASP)marker,KASP-AX-108792274,to further validate this locus in three additional populations in multiple environments.QTa.sau-2 B-769 increased TA by up to 24.9%in these populations.There were significant and positive correlations between TA and flag leaf angle(FLANG).However,TA was not correlated with plant height or anthesis date,suggesting that expression of QTa.sau-2 B-769 is independent of vernalization.Traes CS2 B01 G583800,a gene known to be involved in leaf angle regulation,was identified as the most likely candidate gene for QTa.sau-2 B-769.These results enrich our understanding of the mechanisms regulating wheat TA at maturity and may support precise mapping and cloning of gene(s)underlying QTa.sau-2 B-769.
基金supported by grants from the National Key Research and Development Program of China(2016YFD0100100)the International Science and Technology Cooperation and Exchanges Programs of Science and Technology Department of Sichuan Province(2019YFH0063)the Applied Basic Research Programs of Sichuan Province(2021YJ0297)。
文摘Stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),is one of the most important diseases threatening the yield and stability of wheat production in China and many other countries.Identification and utilization of new genes for durable stripe rust resistance are important for ongoing control of this disease.The objectives of this study were to identify quantitative trait loci(QTL)associated with adult-plant stripe rust resistance in the Chinese wheat landrace Yibinzhuermai(YBZR)and to provide wheat breeders with new sources of potentially durable resistance.A total of 117 recombinant inbred lines(RILs)(F5:8)derived from a cross between YBZR and highly susceptible cultivar Taichung 29(TC29)were assessed for stripe rust severity in field experiments at Wenjiang in 2016 and 2017 and Chongzhou in 2016,2017,2018,and 2019 in Sichuan following inoculation with a mixture of current Pst races.The RILs were genotyped using the Wheat55K single nucleotide polymorphism(SNP)array.Three QTL were identified on chromosome arms 6AL,5BL and 7DS.QYr.YBZR-6AL and QYr.YBZR-7DS conferred major effects in all field environments,explaining 10.6%to 14.7%and 11.5%to 21.2%of phenotypic variation,respectively.The QTL on 5BL and 7DS likely correspond to previously known QTL,whereas QYr.YBZR-6AL is probably novel.Haplotype analysis revealed that the resistance allele at QYr.YBZR-6AL was present in 2.8%of 324 Chinese wheat landraces.SNP markers closely linked with QYr.YBZR-6AL were converted to kompetitive allele-specific PCR markers and validated in the RIL population and a subset of 92 wheat cultivars.QYr.YBZR-6AL and its markers should be useful in breeding programs to improve the level and durability of stripe rust resistance.
基金supported by grants from the Major Program of National Agricultural Science and Technology of China(NK20220607)the National Natural Science Foundation of China(32272059 and 31971883)the Science and Technology Department of Sichuan Province(2021YFYZ0002,2022ZDZX0014,and 2023NSFSC1995)。
文摘Stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease in wheat worldwide.Discovering and characterizing new resistance genes/QTL is crucial for wheat breeding programs.In this study,we fine-mapped and characterized a stripe rust resistance gene,YRAYH,on chromosome arm 5BL in the Chinese wheat landrace Anyuehong(AYH).Evaluations of stripe rust response to prevalent Chinese Pst races in near-isogenic lines derived from a cross of Anyuehong and Taichung 29 showed that YrAYH conferred a high level of resistance at all growth stages.Fine mapping using a large segregating population of 9748 plants,narrowed the YRAYH locus to a 3.7 Mb interval on chromosome arm 5BL that included 61 annotated genes.Transcriptome analysis of two NIL pairs identified 64 upregulated differentially expressed genes(DEGs)in the resistant NILs(NILs-R).Annotations indicated that many of these genes have roles in plant disease resistance pathways.Through a combined approach of fine-mapping and transcriptome sequencing,we identified a serine/threonine-protein kinase SRPK as a candidate gene underlying YrAYH.A unique 25 bp insertion was identified in the NILs-R compared to the NILs-S and previously published wheat genomes.An InDel marker was developed and co-segregated with YrAYH.Agronomic trait evaluation of the NILs suggested that YrAYH not only reduces the impact of stripe rust but was also associated with a gene that increases plant height and spike length.
基金supported by the MOE-AAFC PhD Research Programpartial A-Base funding from Agriculture and Agri-Food Canada.
文摘Genomic DNA and cDNA sequences of an isoamylase gene were isolated and characterized from the rye genome. The full-lengths of the rye isoamylase gene are 7351 bp for genomic DNA and 2364 bp for cDNA. There are 18 exons and 17 introns in the genomic sequence, which shares a similar organization with homologous genes from Aegilops tauschii, maize, rice and Arabidopsis. Exon regions of rye and other plant isoamylase genes are more conserved than the introns. High sequence similarity(>95%) was observed in mature proteins of isoamylase genes originating from rye, Ae. tauschii, wheat and barley. The transcript profile revealed that rye isoamylase is mainly expressed in the seed endosperm with a maximum level at the middle developmental stage(15 DPA). A phylogenetic tree based on the deduced aa sequences of mature proteins from rye and other plant isoamylases indicated that rye isoamylase is more closely related to Ae. tauschii wDBE1 and wheat iso1. This is the first report on identification and characterization of the isoamylase gene from rye, making it possible to explore the roles of this enzyme for amylopectin development in rye and triticale.
基金supported by National Natural Science Foundation of China (No. 41201048)by the Youth Innovation Promotion Association of Chinese Academy of Sciences (2018463)
文摘The Brassicaceae species Braya humilis shows broad adaptation to different climatic zones and latitudes. However, the molecular adaptation mechanism of B. humilis is poorly understood. In China, B. humilis is mainly distributed on the QinghaiTibetan Plateau(QTP) and in the adjacent arid region. Previous transcriptome analysis of B. humilis has revealed that 39 salt and osmotic stress response genes are subjected to purifying selection during its speciation. To further explore the adaptation mechanism of B. humilis to an arid environment, OrthoMCL program was employed in this study and 6,268 pairs of orthologous gene pairs with high confidence were obtained between B. humilis and Arabidopsis thaliana. A comparative evolutionary analysis based on nonsynonymous to synonymous substitution ratio(Ka/Ks) was then conducted. There were 64 pairs exhibiting a Ka/Ks ratio more than 0.5 and among which, three instrumental candidate genes, T20487,T22576, and T23757, were identified with strong selection signatures(Ka/Ks >1). The corresponding A. thaliana orthologs are double-stranded RNA-binding domain protein, MADS-box family protein, and NADH-dehydrogenase subunit6, which is encoded by mitochondria genome. This report not only demonstrates the adaptation contribution of fast evolving nuclear genes, but also highlights the potential adaptive value of mitochondria gene to the speciation and adaptation of B. humilis toward the extreme environment in an arid region.
基金funded in part by the National Key Research and Development Program of China(2023YFA1407200)the NSAF(U2230111,U2330113,U2030103)+4 种基金the National Natural Science Foundation of China(62405114,12404577)the Guangdong Basic and Applied Basic Research Foundation(2025B1515020096,2023A0505050159,2022A1515110970,2023A1515110626)the Guangzhou S&T programme(2025A04J5851)industry-University-Research Cooperation Project of Zhuhai(2320004002614)the Fundamental and Application Foundation Project of Guangzhou(2024A04J3974).
文摘Human vision–inspired neuromorphic devices have integrated architectures that combine sensing,computing,and storage functions,which can fundamentally avoid the energy waste caused by frequent data movement in the currently widely used von Neumann architecture,and have crucial application potential in advanced artificial intelligence chips that pursue low power consumption and low latency.However,previously reported visual neuromorphic devices either suffer complex floating gate,vertically stacked multilayer structures,or necessitate separated optical-sensing and synaptic units,realizing highly compact,nonvolatile optoelectronic response and continuously tunable conductivity within a sententious architecture remains a significant challenge.Here,we presented a low-cost exfoliation and transfer method combined with spin-coating to fabricate molybdenum disulfide(MoS_(2))/barium titanate(BaTiO_(3))heterostructured optoelectronic devices.Based on the ferroelectricity of BaTiO_(3)and the charge transport characteristics of MoS_(2),the hysteresis of ferroelectric polarization upon both electric and optical stimulation is successfully endowed with reliable resistance state switching abilities,showing the advantages of low bias voltage operation(±2 V)and distinct 16 conductance states under light pulse irradiation.Besides,the MoS_(2)/BaTiO_(3)device can be further used to emulate biological synaptic behavior and accomplish the transition from short-term memory(STM)to long-term memory(LTM).Notably,leveraging the dual characteristics of imaging and neuromorphic behavior,we constructed a multi-layer perceptron network integrating visual perception and image recognition,showing an accuracy of 97.6%in the Modified National Institute of Standards and Technology(MNIST)pattern recognition task.This work introduced a simple MoS_(2)/BaTiO_(3)heterojunction architecture device,offering integrated perception,storage,and computing capabilities,providing a new possibility for future compact neuromorphic computing devices.
基金supported by the National Key R&D Program of China(2018YFB2200201)the Science and Technology Program of Guangzhou(202103030001)+2 种基金the National Natural Science Foundation of China(62135012,12074442)the National Key R&D Program of Guangdong Province(2020B0303020001)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01121).
文摘Highly compact lasers with ultra-low threshold and single-mode continuous wave(CW)operation have been a long sought-after component for photonic integrated circuits(PICs).Photonic bound states in the continuum(BICs),due to their excellent ability of trapping light and enhancing light-matter interaction,have been investigated in lasing configurations combining various BIC cavities and optical gain materials.However,the realization of BIC laser with a highly compact size and an ultra-low CW threshold has remained elusive.We demonstrate room temperature CW BIC lasers in the 1310 nm O-band wavelength range,by fabricating a miniaturized BIC cavity in an InAs/GaAs epitaxial quantum dot(QD)gain membrane.By enabling effective trapping of both light and carriers in all three dimensions,ultra-low threshold of 12μW(0.052 kW cm^(-2))is achieved at room temperature.Single-mode lasing is also realized in cavities as small as only 5×5 unit cells(~2.5×2.5μm^(2) cavity size)with a mode volume of 1.16(λ/n)^(3).The maximum operation temperature reaches 70℃ with a characteristic temperature of T_(0)~93.9 K.With its advantages in terms of a small footprint,ultra-low power consumption,and adaptability for integration,the mini-BIC lasers offer a perspective light source for future PICs aimed at high-capacity optical communications,sensing and quantum information.
基金This research was supported by the National Key R&D Program of China(2018YFA0306100)Key-Area Research and Development Program of Guangdong Province(2018B030329001)+3 种基金Science and Technology Program of Guangzhou(202103030001)the National Natural Science Foundation of China(11874437,62035017)the national super-computer center in Guangzhou,the National Natural Science Foundation of China(12074442,91836303)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01X121).
文摘Optical microcavities have widely been employed to enhance either the optical excitation or the photon emission processes for boosting light-matter interactions at the nanoscale.When both the excitation and emission processes are simultaneously facilitated by the optical resonances provided by the microcavities,as referred to the dual-resonance condition in this article,the performances of many nanophotonic devices approach to the optima.In this work,we present versatile accessing of dual-resonance conditions in deterministically coupled quantum-dot(QD)-micropillars,which enables emission from neutral exciton(X)—charged exciton(CX)transition with improved single-photon purity.In addition,the rarely observed up-converted single-photon emission process is achieved under dual-resonance conditions.We further exploit the vectorial nature of the high-order cavity modes to significantly improve the excitation efficiency under the dual-resonance condition.The dual-resonance enhanced light-matter interactions in the quantum regime provide a viable path for developing integrated quantum photonic devices based on cavity quantum electrodynamics(QED)effect,e.g.,highly efficient quantum light sources and quantum logical gates.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFD1201803-2)the Anhui Provincial Major Science and Technology Project(202203a06020005)the National Natural Science Foundation of China(32171954 and 32202322)。
文摘During their co-evolution with herbivorous insects,plants have developed multiple defense strategies that resist pests,such as releasing a blend of herbivory-induced plant volatiles(HIPVs)that repel pests or recruit their natural enemies.However,the responses of insects to HIPVs in maize(Zea mays L.) are not well understood.Here,we demonstrate that the Asian corn borer(ACB,Ostrinia furnacalis),a major insect pest of maize,shows a preference for maize pre-infested with ACB larvae rather than being repelled by these plants.Through combined transcriptomic and metabolomics analysis of ACB-infested maize seedlings,we identified two substances that explain this behavior:(E)-4,8-dimethylnona-1,3,7-triene(DMNT) and(3E,7E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene(TMTT).DMNT and TMTT attracted ACB larvae,and knocking out the maize genes responsible for their biosynthesis via gene editing impaired this attraction.External supplementation with DMNT/TMTT hampered the larvae's ability to locate pre-infested maize.These findings uncover a novel role for DMNT and TMTT in driving the behavior of ACB.Genetic modification of maize to make it less detectable by ACB might be an effective strategy for developing maize germplasm resistant to ACB and for managing this pest effectively in the field.
文摘Self-assembled semiconductor quantum dots(QDs)are potentially scalable candidates for solid-state single-photon emitters which deterministically generate one single-photon per excitation.Such on-demand single-photon sources serve as one of the key elements in modern photonic quantum technologies[1].Until very recently,near-optimal QD single-photon sources with simultaneous high degree of brightness,single-photon purity and indistin-
基金National Natural Science Foundation of China(62035017,12074442)National Key Research and Development Program of China(2018YFA0306103)+1 种基金Science and Technology Program of Guangzhou(202103030001)Hisilicon Technologies CO.,LIMITED and the national super-computer center in Guangzhou.
文摘The emerging hybrid integrated quantum photonics combines the advantages of different functional components into a single chip to meet the stringent requirements for quantum information processing.Despite the tremendous progress in hybrid integrations of III-V quantum emitters with silicon-based photonic circuits and superconducting single-photon detectors,on-chip optical excitations of quantum emitters via miniaturized lasers towards single-photon sources(SPSs)with low power consumptions,small device footprints,and excellent coherence properties is highly desirable yet illusive.In this work,we present realizations of bright semiconductor SPSs heterogeneously integrated with on-chip electrically-injected microlasers.Different from previous one-by-one transfer printing technique implemented in hybrid quantum dot(QD)photonic devices,multiple deterministically coupled QD-circular Bragg Grating(CBG)SPSs were integrated with electrically-injected micropillar lasers at one time via a potentially scalable transfer printing process assisted by the wide-field photoluminescence(PL)imaging technique.Optically pumped by electrically-injected microlasers,pure single photons are generated with a high-brightness of a count rate of 3.8 M/s and an extraction efficiency of 25.44%.Such a high-brightness is due to the enhancement by the cavity mode of the CBG,which is confirmed by a Purcell factor of 2.5.Our work provides a powerful tool for advancing hybrid integrated quantum photonics in general and boosts the developments for realizing highly-compact,energy-efficient and coherent SPSs in particular.
基金Supported by the National Natural Science Foundation of China(No.11061006)the Science Foundation of Education Department of Guangxi Province(No.201012MS025)
文摘This paper deals with the existence of denumberable positive solutions to boundary value problems of delay differential equations with denumberable singularities on infinite intervals.By the fixed-point index theory and a new fixed-point theorem in cones,the existence of denumberable positive solutions is obtained under some suitable growth conditions imposed on the nonlinear term.
