Flag leaf angle(FLANG)is one of the key traits in wheat breeding due to its impact on plant architecture,light interception,and yield potential.An image-based method of measuring FLANG in wheat would reduce the labor ...Flag leaf angle(FLANG)is one of the key traits in wheat breeding due to its impact on plant architecture,light interception,and yield potential.An image-based method of measuring FLANG in wheat would reduce the labor and error of manual measurement of this trait.We describe a method for acquiring in-field FLANG images and a lightweight deep learning model named LeafPoseNet that incorporates a spatial attention mechanism for FLANG estimation.In a test dataset with wheat varieties exhibiting diverse FLANG,LeafPoseNet achieved high accuracy in predicting the FLANG,with a mean absolute error(MAE)of 1.75°,a root mean square error(RMSE)of 2.17°,and a coefficient of determination(R2)of 0.998,significantly outperforming established models such as YOLO12x-pose,YOLO11x-pose,HigherHRNet,Lightweight-OpenPose,and LitePose.We performed phenotyping and genome-wide association study to identify the genomic regions associated with FLANG in a panel of 221 diverse bread wheat genotypes,and identified 10 quantitative trait loci.Among them,qFLANG2B.2 was found to harbor a potential causal gene,TraesCS2B01G313700,which may regulate FLANG formation by modulating brassinosteroid levels.This method provides a low-cost,high-accuracy solution for in-field phenotyping of wheat FLANG,facilitating both wheat FLANG genetic studies and ideal plant type breeding.展开更多
Leaf thickness in rice critically influences photosynthetic efficiency and yield,yet its genetic basis remains poorly understood,with few functional genes previously characterized.In this study,we employ a pangenome-w...Leaf thickness in rice critically influences photosynthetic efficiency and yield,yet its genetic basis remains poorly understood,with few functional genes previously characterized.In this study,we employ a pangenome-wide association study(Pan-GWAS)on 302 diverse rice accessions from southern China,identifying 49 quantitative trait loci(QTLs)associated with leaf thickness.The most significant locus,qLT9,is fine-mapped to a 79-kb region on chromosome 9.Transcriptomic and genomic sequence analyses identify LOC_Os09g33480,which encodes a protein belonging to Multiple Organellar RNA Editing Factor family,as the key candidate gene.Overexpression and complementation transgenic experiments confirm LOC_Os09g33480(OsLT9)as the functional gene underlying qLT9,demonstrating a 24-bp Indel in its promoter correlates with the expression levels and leaf thickness.Notably,OsLT9 overexpression lines show not only thicker leaf,but also significantly enhanced photosynthetic efficiency and grain yield,establishing a link between leaf thickness modulation and yield enhancement.Population genomic analyses indicate strong selection for OsLT9 during domestication and breeding,with modern cultivars favoring thick leaf haplotype of OsLT9.This study establishes OsLT9 as a key regulator controlling leaf thickness in rice,and provides a valuable genetic resource for molecular breeding of high-yielding rice through optimization of plant architecture.展开更多
Leaf angle is a pivotal agronomic trait that significantly influences crop architecture and yield.Plant hormones,such as auxin,play a critical role in regulating leaf angle;however,the underlying molecular mechanisms ...Leaf angle is a pivotal agronomic trait that significantly influences crop architecture and yield.Plant hormones,such as auxin,play a critical role in regulating leaf angle;however,the underlying molecular mechanisms remain to be fully elucidated.Here,we reveal that the auxin response factor gene,OsARF12,which is highly expressed in the leaf lamina joint,negatively regulates rice(Oryza sativa L.)leaf angle via affecting shoot gravitropism.Overexpression lines of OsARF12 exhibit more erect leaf angles,while the osarf12 mutants display enlarged leaf angles compared to the wild type.Further studies demonstrate that OsARF12 directly activates the expression of Loose Plant Architecture1(LPA1)and LAZY1 by binding to their promoters.The osarf12 mutant presents impaired shoot gravitropism,a phenotype consistent with that of the lpa1 and lazy1 mutants.Collectively,we elucidate the biological functions of OsARF12,which modulates leaf angle through its impact on shoot gravitropism by regulating the expression levels of LPA1 and LAZY1.This study provides insight into the role of auxin in determining rice leaf angle,potentially holding profound effects for the optimization of crop architecture.展开更多
The high hydrophilicity of pineapple leaf fibres(PALF)limits their use in cement-and gypsum-based composites exposed to moisture.This study evaluates,for the first time,the combined effect of palm kernel oil and beesw...The high hydrophilicity of pineapple leaf fibres(PALF)limits their use in cement-and gypsum-based composites exposed to moisture.This study evaluates,for the first time,the combined effect of palm kernel oil and beeswax on the hygroscopic resistance and mechanical stability of PALF.The fibres were functionalised with three formulations(oil,wax,and a 1:2 oil/wax blend)applied at different mass ratios(CR=0.5-2).Treatments increased the average bundle diameter by up to+46%(238μm)and reduced density down to 1.06 g/cm^(3).Hygroscopically,water absorption decreased from 202.4%(raw fibres)to 76.3%(CR=2),representing a maximum reduction of 59.4%in saline medium,while moisture regain dropped from 27.9%to 14.6%(−47.7%).The oil/wax blend proved most effective,simultaneously reducing water absorption(−51.2%)and moisture regain(−46.8%)at CR=1.Mechanically,the fibres retained tensile strength(415.2 vs.460.8 MPa,+11%at CR=1)and exhibited enhanced ductility(+62.5%,with elongation at break increasing from 1.6%to 2.6%),without significantly altering Young’s modulus(12.3 to 10 GPa).Water absorption kinetics were accurately described by the Czel and Mohsenin models(R^(2)>0.98).These findings clearly demonstrate that bio-based lipid coatings can provide an eco-friendly alternative to conventional chemical treatments.They improve hygroscopic resistance and preserve mechanical integrity of PALF,providing original quantitative data for their integration into durable cement-and gypsum-based composites subjected to humid or cyclic wet-dry conditions.展开更多
The establishment of plantations has become a critical approach for reducing greenhouse gas emissions,particularly in fragile environments with carbon sequestration potential.In karst areas,plantations based on fastgr...The establishment of plantations has become a critical approach for reducing greenhouse gas emissions,particularly in fragile environments with carbon sequestration potential.In karst areas,plantations based on fastgrowing afforestation species made significant contributions to enhancing carbon sequestration.However,the impact of understory vegetation on carbon accumulation remains unclear.Especially,the carbon accumulation associated with litter produced during the replacement of understory species receives insufficient attention,which leads to the neglect of the carbon sequestration potential in plantations of karst areas.Leaf is a crucial organ that links the litter production.To explore how leaf traits adapt to competitive environments and drive litter carbon accumulation during understory species replacement,this study observed leaf traits and litter carbon content changes in three types of plantations in the Liujiang River Basin,a typical karst area.A total of 37 sampling plots were selected for field investigation over a twoyear period.Leaf traits,species diversity,vegetation coverage,and litter carbon characteristics in understory vegetation were measured.Variance analysis,allometric equations,and path analysis were used for data analysis.The results showed that most understory species adopted a biomass conservation strategy under high-coverage conditions(>44.27%)and expanded competitive leaf area under low-coverage conditions(<44.27%).However,Bidens pilosa and Miscanthus floridulus exhibited strong competitiveness during understory species replacement.They showed an expansion of competitive leaf area under high-coverage conditions.This competitive strategy reduced species diversity and community specific leaf area.But the rapid expansion of Bidens pilosa and Miscanthus floridulus increased understory vegetation coverage,and their increased specific leaf area facilitated leaf shedding,resulting in significant litter weight accumulation(P<0.05),thereby enhancing litter carbon content per unit area.These competitive strategies were key driving factors for the increase in litter carbon content per square meter,which reached a maximum of 49.6% higher than that in natural grasslands.And the maximum increase in litter carbon accumulation derived from understory vegetation reached 3.37 times from 2023 to 2024 in plantations.In the understory vegetation of plantations,the competitive strategies reflected by leaf adaptation of key competitive species are critical factors influencing litter carbon accumulation.Future research could deeply explore the carbon sequestration effects resulting from the dynamic changes in competition within the understory vegetation of plantations.展开更多
The trade-off between leaf size and leafing intensity(i.e.,the number of leaves per unit stem size)is a key axis of trait covariation across the diversity of plant foliage deployment.However,the functional significanc...The trade-off between leaf size and leafing intensity(i.e.,the number of leaves per unit stem size)is a key axis of trait covariation across the diversity of plant foliage deployment.However,the functional significance of leafing intensity and its possible combinations with leaf size in dealing with water limitation remains unclear.Using Populus euphratica as an illustrative tree species growing in hyper-arid climates,we investigated how leaf size and leafing intensity co-varied under varying water stresses.In the Ebinor lowlands and the upper reaches of the Tarim River(NW China),we sampled>1800 current-year twigs from 505 trees across 14 sites along a climatic gradient characterized by precipitation,potential evapotranspiration and vapor pressure deficit.Leafing intensity based on stem mass(LIM)decreased with climatic aridity,primarily due to greater stem mass,but not fewer leaves.This indicates a higher investment in structural support for leaf attachment under water stress.Both leaf area and mass decreased with LIM at a lower-than-proportional rate,with the decrease in leaf size being more pronounced under drier climates.This suggests that higher LIM incurs a high cost of reducing leaf size in water-limited habitats.These findings challenge the assumption that higher leafing intensity always confers an advantage ready for environmental stresses due to higher developmental flexibility offered by more axillary buds.Rather,we propose that a strategy of lower leafing intensity,with greater structural support for leaf attachment and less compromise in leaf size,can be advantageous under water limitation.展开更多
Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify...Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify TSEMF in response to environmental changes.However,there has been limited exploration of multitrait combinations for predicting TS-EMF across seasons and of trait thresholds that enhance TS-EMF.Here,for 10 dominant tree species in urban forests of Northeast China,14 traits were measured and four aboveground and three belowground ecological functions assessed in three seasons.Ecological functions and TS-EMF differed significantly throughout the seasons(P<0.05).Synergistic relationships were found between carbon sequestration and oxygen release,between cooling and humidification,and between organic carbon accumulation and nutrient cycling.Notably,aboveground multifunctionality played a leading role in TS-EMF.With seasonal changes,resource allocation shifted toward traits related to resource acquisition rather than conservation to maintain TS-EMF.The combination of traits that predicted TS-EMF varied by type,accounting for up to 66.45%of the variation.TS-EMF was primarily driven by leaf structure in spring and by nutrient accumulation in autumn.Leaf carbon content(LCC)consistently served as a stabilizing factor for predicting TS-EMF across seasons.At 36.5-36.8 mg g^(-1),LCC had its optimal effect on TS-EMF.Other traits in combination that positively influence total TS-EMF include leaf nitrogen content(3.43-3.45 mg g^(-1)),leaf phosphorus content(0.80-0.83 mg g^(-1)),and leaf area(65.86-68.43 cm^(2)).Within these specified trait thresholds,Morus alba and Quercus mongolica were identified as key species.These findings suggest that the trade-off between various ecological functions can be managed by altering plant traits across seasons.This approach could provide a theoretical foundation for enhancing the TS-EMF of urban forests through trait-based management,offering practical guidance for selecting tree species.展开更多
Background As living standards improve,consumers are placing greater emphasis on the enhancement of fish flesh quality,making its improvement increasingly critical.Plant-derived polysaccharides positively affect the i...Background As living standards improve,consumers are placing greater emphasis on the enhancement of fish flesh quality,making its improvement increasingly critical.Plant-derived polysaccharides positively affect the improvement of animal flesh quality.Panax ginseng leaf polysaccharides(PGLP)have a similar composition and lower cost compared with Panax ginseng root polysaccharides.However,its function and application effects in grass carp(Ctenopharyngodon idella)are unclear.Methods A total of 540 sub-adult grass carp(679±1.29 g),one of the important economic fish species,were used as experimental models and fed diets supplemented with 0,100,200,300,400,or 500 mg/kg PGLP for 60 d.After 60 d,grass carp were weighed,and their muscles were collected to explore the effects of PGLP on the growth and development of myofibers and energy metabolism-related parameters.Results Our study found that PGLP increased the growth performance and muscle nutritional composition as well as improved muscle hardness,springiness,cohesiveness,chewiness,and hyperplasia of myofibers of sub-adult grass carp.Besides,PGLP promoted muscle energy metabolism by increasing creatine,glycogen,pyruvate,and acetyl-CoA contents and creatine kinase(CK),pyruvate kinase(PK),phosphofructokinase(PFK),and hexokinase(HK)activities,while decreasing lactate dehydrogenase(LDH)activity and lactate content in fish muscle.Finally,our study found that PGLP enhanced mitochondrial function by increasing the protein expression of mitochondrial complexes I–V,biogenesis,and fusion and decreasing autophagy and fission in fish muscle.Conclusions PGLP improved growth performance and flesh quality of sub-adult grass carp,which may be related to enhancing hyperplasia of myofibers by promoting energy metabolism.We concluded that the recommended amount of PGLP in sub-adult grass carp feed to optimize growth performance is 100–200 mg/kg.This study provides a theoretical basis for the application of PGLP in fish feed and for the analysis of the mechanism of nutrition and feed regulating fish flesh quality,which is of great significance.展开更多
Four modern hybrid and four japonica rice varieties differing in biomass,yield,and daily biomass production rate during the grain-filling period(DBPGF),were used to reveal the eco-physiological photosynthetic characte...Four modern hybrid and four japonica rice varieties differing in biomass,yield,and daily biomass production rate during the grain-filling period(DBPGF),were used to reveal the eco-physiological photosynthetic characteristics of high-yield and high-efficiency rice.Varietal differences were analyzed in leaf and canopy photosynthetic parameters,associated leaf morphological and anatomical traits(e.g.,stomatal density,vein density,mesophyll cell arrangement),as well as differences in canopy light interception and leaf area index,and their effects on yield and biomass accumulation.Hybrid rice with yield higher than 11.0 t/hm^(2) and DBPGF higher than 200 kg/(hm^(2)·d),and japonica rice with yield higher than 9.0 t/hm^(2) and DBPGF higher than 200 kg/(hm^(2)·d),were classified as high-yield and high-efficiency varieties;other varieties were considered general types.Based on this criterion,two hybrid(Yongyou 2640 and Shanyou 63)and two japonica varieties(Huaidao 5 and Nangeng 5718)were categorized as high-yield and high-efficiency types,while the remaining two hybrid(Liangyoupeijiu and C Liangyou 513)and two japonica varieties(Suxiu 867 and Yangnongdao 1)were classified as general types.Results indicated that high-yield and high-efficiency varieties generally have higher leaf and canopy photosynthesis,superior leaf stomatal,vascular,and mesophyll structures that facilitate CO_(2)diffusion and hydraulic transport,higher canopy light transmittance,and slower leaf area attenuation.Rice yield and biomass were positively correlated with photosynthetic parameters and closely linked to associated photosynthetic traits.Efficient rice production was attributed to coordinated improvements in leaf structure,canopy architecture,and delayed leaf area attenuation.This study provides important theoretical guidance for breeding high-efficiency rice varieties.展开更多
To ascertain the genetic diversity of gray leaf spot pathogen on Dictamnus dasycarpus popoulation in Heilongjiang Province,a total of 57 strains of Paracercospora dictamnicola were isolated and purified from the disea...To ascertain the genetic diversity of gray leaf spot pathogen on Dictamnus dasycarpus popoulation in Heilongjiang Province,a total of 57 strains of Paracercospora dictamnicola were isolated and purified from the diseased samples collected from five Chinese herbal medicine planting areas in Heilongjiang Province between the years of 2021 and 2022.Repetitive extragenic palindromic polymerase chain reaction(Rep–PCR)was used to amplify 57 isolates of gray leaf spot pathogen on D.dasycarpus from different regions of Heilongjiang Province.The polymorphic bands amplified by three sets of primers accounted for more than 80%.Cluster analysis results showed that at a similarity coefficient of 0.67,the gray leaf spot pathogen on D.dasycarpus in Heilongjiang Province could be divided into five major genetic groups.Genetic diversity parameter analysis indicated that there were certain differences in genetic richness among the geographic populations of gray leaf spot pathogen on D.dasycarpus from different regions.Analysis of molecular variance(AMOVA)revealed that genetic variation among strains mainly originated within populations.The genetic differentiation and relationships of gray leaf spot pathogen on D.dasycarpus from different geographic regions of Heilongjiang Province indicated that genetic differentiation and kinship among populations were somewhat related to their geographic distance.The greater the geographic distance,the higher the genetic differentiation coefficient,and the lower the genetic uniformity among populations.展开更多
[Objective] To provide scientific basis for high phosphorus efficiency cultivation and regulation of rice. [Method] Changbai9 （CB9） and Jijing81 （JJ81） were used as experimental materials for pot experiment, and f...[Objective] To provide scientific basis for high phosphorus efficiency cultivation and regulation of rice. [Method] Changbai9 （CB9） and Jijing81 （JJ81） were used as experimental materials for pot experiment, and five levels of phosphorus nutrient （ Po - P4 ） were set for each variety, the net photosynthesis rate, Chlorophyll Meter Readings （SPAD Readings）, stomatal conductance, transpiration rate, intercellular CO2 concentration, and stomatal limitation were observed and compared between five different phosphorus levels at filling stage. [ Result] The net photosynthesis rate of CB9 reached the highest at P3, and was significantly different from other treatments （P 〈0.05）;the net photosynthesis rate of groups with phosphorus of J J81 were higher than that of the control group,and reached the highest at P,. The SPAD Readings of CB9 and JJ81 all achieved the highest at P3, and stomatal conductance and transpiration rate were all at first increased then decreased with the phosphor- us increased in CB9 and JJ81. With the phosphorus increased, intercellular CO2 concentration of CB9 decreased at first and then increased, while in JJ81 the trend was inversed,but the tendency of intercellular CO2 concentration were opposite to that of stomatal limitation in both culti- vars. [ Conclusion] Appropriate adding phosphorus could improve photosynthetic characteristic of rice flag-leaf,but displayed significant genotypic difference.展开更多
The changes in photochemical features of Photosystem Ⅱ (PS Ⅱ) and contents of Rubisco large subunit (RLS) and small subunit (RSS) in flag leaf from 75DAS to 113DAS (from filling to harvesting stages) were investigat...The changes in photochemical features of Photosystem Ⅱ (PS Ⅱ) and contents of Rubisco large subunit (RLS) and small subunit (RSS) in flag leaf from 75DAS to 113DAS (from filling to harvesting stages) were investigated in two hybrid rices (Oryza sativa L) cv. Liangyoupeijiu and cv. Shanyou 63 grown in the field. Liangyoupeijiu is a super high-yielding rice and Shanyou 63 has widely been planted in China in these years. The results indicate that soluble protein and chlorophyll in both cultivars degraded slowly at first and dramatically thereafter. The degradation speed of soluble protein in Shanyou 63 was faster than that in Liangyoupeijiu. Both Fv/Fm and qP decreased in parallel with leaf senescence, whereas qN fell at first and then rose. No significant change in excitation pressure (1-qP) was found before 89DAS but a sharply increase in both cultivars after it occurred. Excitation pressure rose more rapidly in Shanyou 63 than that in Liangyoupeijiu. The changes of RLS and RSS content exhibited the same trend as that of soluble protein content. A better linear correlation between RLS, RSS degradation and elevation of (1-qP) were shown in both cultivars. We suggest that the increase in PSⅡ excitation pressure possibly induced the quick senescence process in rice flag leaf. The high-yielding of Liangyoupeijiu may be due to its maintenance of stronger photosynthetic capacity, longer and more stable photosynthetic functional du-ration than that of Shanyou 63.展开更多
[Objective] The aim was to conduct non-destructive monitoring on wheat leaf in field and discuss the method to measure geometric phenotype of flag leaf through digital image processing in order to establish relationsh...[Objective] The aim was to conduct non-destructive monitoring on wheat leaf in field and discuss the method to measure geometric phenotype of flag leaf through digital image processing in order to establish relationship between geometric pheno- type of flag leaf and N fertilizer regulation. [Method] Ningmai 13 was applied with N fertilizers in different amounts to discuss relationship among area, length, average width of flag leaf and applied N fertilizers using digital camera and digital image pro- cessing technique. [Result] Fertilizer is a main environmental factor influencing geo- metric phenotype of flag leaf, for example, area of flag leaf would enlarge four times and the length would increase from 15.87 to 25.33 cm by different N fertilizer amount. Thus, geometric phenotype of flag leaf would reflect N fertilizer amount at early stage. The highly accurate relationship between phenotype and N fertilizer is a reliable tech- nique to study on rules of wheat phenotype, N fertilizer and environmental factors. [Conclusion] The research indicated that digital image processing technique with scale label and dynamic background plates is an effective method to obtain geometric phenotype of sessile crops and crops with little leaf, providing a feasible scheme for non- destructive monitoring on growth dynamic of leaf＇s organs.展开更多
To understand genetic patterns of the morphological and physiological traits in flag leaf of barley, a double haploid （DH） population derived from the parents Yerong and Franklin was used to determine quantitative t...To understand genetic patterns of the morphological and physiological traits in flag leaf of barley, a double haploid （DH） population derived from the parents Yerong and Franklin was used to determine quantitative trait loci （QTL） controlling length, width, length/width, and chlorophyll content of flag leaves. A total of 9 QTLs showing significantly additive effect were detected in 8 intervals on 5 chromosomes. The variation of individual QTL ranged from 1.9% to 20.2%. For chlorophyll content expressed as SPAD value, 4 QTLs were identified on chromosomes 2H, 3H and 6H; for leaf length and width, 2 QTLs located on chromosomes 5H and 7H, and 2 QTLs located on chromosome 5H were detected; and for length/width, I QTL was detected on chromosome 7H. The identification of these QTLs associated with the properties of flag leaf is useful for barley improvement in breeding programs.展开更多
Premature senescence after anthesis reduces crop yields.Delaying leaf senescence could maintain photosynthetic activity for a longer period and lead to a higher photosynthetic rate.Recent studies have provided some in...Premature senescence after anthesis reduces crop yields.Delaying leaf senescence could maintain photosynthetic activity for a longer period and lead to a higher photosynthetic rate.Recent studies have provided some insights into the interaction between cytokinin and nitrogen(N)in the regulation of plant development.In the present study,foliar application of exogenous 6-benzylaminopurine(6-BA)and lovastatin,an inhibitor of cytokinin synthesis,was combined with three N rates[0 kg ha^(-1)(low nitrogen,LN),240 kg ha^(-1)(normal nitrogen,NN),and 360 kg ha^(-1)(high nitrogen,HN)]in two wheat cultivars,Wennong 6(with a staygreen phenotype)and Jimai 20(with a non-staygreen phenotype).Flag leaf senescence was assessed using a Gompertz growth curve.Grain mass,dry matter accumulation and distribution,total N of flag leaf,and concentrations of zeatin riboside(ZR)and abscisic acid(ABA)were also used to evaluate the functional characteristics of flag leaves.Grain mass was negatively correlated with initial senescence rate(r_0)and duration of rapid chlorophyll loss(Chl_(loss)),whereas it was positively correlated with maximum senescence rate(r_(max)),average senescence rate(r_(aver)),persistence phase(Chl_(per)),total duration of flag leaf(Chl_(total))and inflection point cumulative temperature(M).Compared to Jimai 20,Wennong 6 had larger r_(aver),Chl_(per),and Chl_(total).The concentration of ZR was highest under the 6-BA×NN treatment,followed by the 6-BA×HN and 6-BA×LN treatments.However,the concentration of ABA showed the opposite trend.It was concluded that the staygreen phenotype Wennong 6 was associated with greater grain mass and altered cytokinin metabolism and could be classified as a functional staygreen type.Foliar application of 6-BA interacting with N at the NN level(240 kg ha^(-1))may be a beneficial strategy for improving grain yield of wheat by regulating endogenous hormones and the flag leaf senescence process.Increasing endogenous cytokinin promoted the transport of dry matter to grain.展开更多
In order to identify the optimum period of spring water-restrictive irrigation for winter wheat(Triticum aestivum L.)in the Haihe Plain,China and elucidate its effects on flag leaf senescence and yield formation,field...In order to identify the optimum period of spring water-restrictive irrigation for winter wheat(Triticum aestivum L.)in the Haihe Plain,China and elucidate its effects on flag leaf senescence and yield formation,field experiments were conducted at the Xinji Experimental Station of Hebei Agricultural University from 2016 to 2019 by using different irrigation regimes in spring,including the conventional regime involving two irrigation periods(control(CK),the 3-leaf unfolding stage and the anthesis stage)and a series of single,restrictive irrigation regimes(SRI)comprising irrigation at the 3-leaf unfolding stage(3 LI),4 LI,5 LI,and 6 LI.There are five major findings:(1)The senescence(determined by the green leaf area,GLA)in the 4 LI treatment occurred moderately earlier than that in CK,showed no significant difference with that in 5 LI and 6 LI,and occurred significantly later than that in 3 LI.(2)Compared with other SRI treatments,the GLA value and photosynthetic rate in 4 LI were 14.82 and 20.1%higher,respectively.Microstructural analysis of flag leaf also revealed that the mesophyll cells and chloroplasts were irregularly arranged under drought stress in 3 LI and 6 LI;however,drought stress had minimal negative effects on the microstructure in 4 LI and 5 LI.(3)Postponed irrigation in spring could significantly increase superoxide dismutase(SOD)and catalase(CAT)activities in the early stage of grain filling;however,these activities would subsequently decrease.Among the four SRI treatments,the overall enzyme activities were the highest in 4 LI,and the combined malondialdehyde(MDA)content in flag leaves in 4 LI and 5 LI was 14.5%lower on average than that in 3 LI and 6 LI.(4)The soluble sugar(SS)and proline(Pro)contents in 4 LI were the highest among the four SRI treatments;however,they were lower than those in CK.The abscisic acid(ABA)hormone content in 4 LI and 5 LI was lower than that in 3 LI and 6 LI,respectively,suggesting a smaller drought stress effect in 4 LI and 5 LI.(5)In two growing seasons,there was a larger number of spikes per unit area in 4 LI(i.e.,13.4%higher than that in 5 LI and 6 LI)and the 1000-grain weight in 4 LI was the highest among the four SRI treatments(i.e.,6.0%higher than that in the other three SRI treatments).Therefore,a single restrictive irrigation regime at the 4-leaf unfolding stage is recommended to be effective in slowing down the senescence process of flag leaves and achieving high yield.展开更多
The response of transcription factor genes to low nitrogen stress was studied to provide molecular basis for improving the absorption and utilization efficiency of nitrogen fertilizer in rice. The agilent rice genome ...The response of transcription factor genes to low nitrogen stress was studied to provide molecular basis for improving the absorption and utilization efficiency of nitrogen fertilizer in rice. The agilent rice genome arrays were used to study the varied expression of transcription factor genes in two rice varieties （SN 196 and Toyonishhiki） with different chlorophyll contents under low nitrogen stress. The results showed that a total of 53 transcription factor genes （35 down-regulated and 18 up-regulated genes at the transcription level） in flag leaves of super-green rice SN196 and 27 transcription factor genes （21 down-regulated and 6 up-regulated genes at the transcription level） in flag leaves of Toyonishiki were affected by low nitrogen stress. Among those nitrogen-responsive genes, 48 transcription factor genes in SN196 and 22 in Toyonishiki were variety-specific. There were overlapped transcription factor genes responded to low nitrogen stress between SN196 and Toyonishiki, with 1 up-regulated and 4 down-regulated at the transcription level. Distributions of low nitrogen responsive genes on chromosomes were different in two rice varieties.展开更多
Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,j...Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,je0407,with an 84.34%-89.35%smaller flag leaf angle compared with the wild type.The mutant also had an abnormal lamina joint and no ligule or auricle.Genetic analysis indicated that the ligule was controlled by two recessive genes,which were mapped to chromosomes 2AS and 2DL.The mutant allele on chromosome 2AS was named Tafla1b,and it was fine mapped to a 1 Mb physical interval.The mutant allele on chr.2DL was identified as Taspl8b,a novel allele of TaSPL8 with a missense mutation in the second exon,which was used to develop a cleaved amplified polymorphic sequence marker.F3 and F4 lines derived from crosses between Jing411 and je0407 were genotyped to investigate interactions between the Tafla1b and Taspl8b alleles.Plants with the Tafla1b/Taspl8a genotype had 58.41%-82.76%smaller flag leaf angles,6.4%-24.9%shorter spikes,and a greater spikelet density(0.382 more spikelets per cm)compared with the wild type.Plants with the Tafla1a/Taspl8b genotype had 52.62%-82.24%smaller flag leaf angles and no differences in plant height or spikelet density compared with the wild type.Tafla1b/Taspl8b plants produced erect leaves with an abnormal lamina joint.The two alleles had dosage effects on ligule formation and flag leaf angle,but no significant effect on thousand-grain weight.The mutant alleles provide novel resources for improvement of wheat plant architecture.展开更多
Genetic segregation analysis for flag leaf angle was conducted using six generations of P1, P2, F1, B1, B2 and F2 derived from a cross of 863B （a maintainer line of japonica rice） and A7444 （a germplasm with large ...Genetic segregation analysis for flag leaf angle was conducted using six generations of P1, P2, F1, B1, B2 and F2 derived from a cross of 863B （a maintainer line of japonica rice） and A7444 （a germplasm with large flag leaf angle）. Genotypes and phenotypes of flag leaf angle were investigated in 863B （P1）, A7444 （P2） and 141 plants in BC^F~ （863BIA744411863B） population. An SSR genetic linkage map was constructed and QTLs for flag leaf angle were detected. The genetic map containing 79 information loci was constructed, which covers a total distance of 441.6 cM, averaging 5.6 cM between two neighboring loci. Results showed that the trait was controlled by two major genes plus polygene and the major genes were more important. Fifteen markers showed highly significant correlations with flag leaf angle based on single marker regression analysis. Two QTLs （qFLA2 and qFLA8） for flag leaf angle were detected by both composite interval method in software WinQTLCart 2.5 and composite interval method based on mixed linear model in QTL Network 2.0. The qFLA2 explained 10.50% and 13.28% of phenotypic variation, respectively, and was located at the interval of RM300 and RM145 on the short arm of chromosome 2. The qFLA8 explained 9.59% and 7.64% of phenotypic variation, respectively, and was located at the interval flanking RM6215 and RM8265 on the long arm of chromosome 8. The positive alleles at the two QTLs were both contributed from A7444.展开更多
Cuticular wax plays an important role in protecting land plant against biotic and abiotic stresses. Cuticular wax production on plant surface is often visualized by a characteristic glaucous appearance. This study ide...Cuticular wax plays an important role in protecting land plant against biotic and abiotic stresses. Cuticular wax production on plant surface is often visualized by a characteristic glaucous appearance. This study identified quantitative trait loci （QTLs） for wheat （Triticum aestivum L.） flag leaf glaucousness （FLG） using a high-density genetic linkage map developed from a recombinant inbred line （RIL） population derived from the cross HeynexLakin by single-seed descent. The map consisted of 2 068 single nucleotide polymorphism （SNP） markers and 157 simple sequence repeat （SSR） markers on all 21 wheat chromosomes and covered a genetic distance of 2 381.19 cM, with an average marker interval of 1.07 cM. Two additive QTLs for FLG were identified on chromosomes 3AL and 2DS with the increasing FLG allele contributed from Lakin. The major QTL on 3AL, QFIg.hwwgr-3AL, explained 17.5-37.8% of the phenotypic variation in different environments. QFIg.hwwgr-3AL was located in a 4.4-cM interval on chromosome 3AL that was flanked by two markers IWA1831 and IWA8374. Another QTL for FLG on 2DS, designated as QFIg.hwwgr-2DS which was identified only in Yangling in 2014 （YL14）, was flanked by IWA1939 and Xgwm261 and accounted for 11.3% of the phenotypic variation for FLG. QFIg.hww- gr-3AL and QFIg.hwwgr-2DS showed Additive×Environment （AE） interactions, explaining 3.5 and 4.4% of the phenotypic variance, respectively. Our results indicated that different genes/QTLs may contribute different scores of FLG in a cultivar and that the environment may play a role in FLG.展开更多
基金supported by the Biological Breeding-National Science and Technology Major Project(2023ZD04076)the National Key Research and Development Program of China(2023YFF1000100)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA0450000).
文摘Flag leaf angle(FLANG)is one of the key traits in wheat breeding due to its impact on plant architecture,light interception,and yield potential.An image-based method of measuring FLANG in wheat would reduce the labor and error of manual measurement of this trait.We describe a method for acquiring in-field FLANG images and a lightweight deep learning model named LeafPoseNet that incorporates a spatial attention mechanism for FLANG estimation.In a test dataset with wheat varieties exhibiting diverse FLANG,LeafPoseNet achieved high accuracy in predicting the FLANG,with a mean absolute error(MAE)of 1.75°,a root mean square error(RMSE)of 2.17°,and a coefficient of determination(R2)of 0.998,significantly outperforming established models such as YOLO12x-pose,YOLO11x-pose,HigherHRNet,Lightweight-OpenPose,and LitePose.We performed phenotyping and genome-wide association study to identify the genomic regions associated with FLANG in a panel of 221 diverse bread wheat genotypes,and identified 10 quantitative trait loci.Among them,qFLANG2B.2 was found to harbor a potential causal gene,TraesCS2B01G313700,which may regulate FLANG formation by modulating brassinosteroid levels.This method provides a low-cost,high-accuracy solution for in-field phenotyping of wheat FLANG,facilitating both wheat FLANG genetic studies and ideal plant type breeding.
基金supported by the National Natural Science Foundation of China(32301845)GuangDong Basic and Applied Basic Research Foundation(2022A1515012339)+3 种基金the National Key R&D Program of China(2024YFD1200801)Seed industry revitalization project of special fund for rural revitalization strategy in Guangdong Province(2024-NPY-00-001)Modern Seed Industry Innovation Capacity Enhancement Progject of Guangdong Academy of Agricultural Sciences,Elite Rice Plan of GDRRI(2023YG01)Guangdong Key Laboratory of Rice Science and Technology(2023B1212060042).
文摘Leaf thickness in rice critically influences photosynthetic efficiency and yield,yet its genetic basis remains poorly understood,with few functional genes previously characterized.In this study,we employ a pangenome-wide association study(Pan-GWAS)on 302 diverse rice accessions from southern China,identifying 49 quantitative trait loci(QTLs)associated with leaf thickness.The most significant locus,qLT9,is fine-mapped to a 79-kb region on chromosome 9.Transcriptomic and genomic sequence analyses identify LOC_Os09g33480,which encodes a protein belonging to Multiple Organellar RNA Editing Factor family,as the key candidate gene.Overexpression and complementation transgenic experiments confirm LOC_Os09g33480(OsLT9)as the functional gene underlying qLT9,demonstrating a 24-bp Indel in its promoter correlates with the expression levels and leaf thickness.Notably,OsLT9 overexpression lines show not only thicker leaf,but also significantly enhanced photosynthetic efficiency and grain yield,establishing a link between leaf thickness modulation and yield enhancement.Population genomic analyses indicate strong selection for OsLT9 during domestication and breeding,with modern cultivars favoring thick leaf haplotype of OsLT9.This study establishes OsLT9 as a key regulator controlling leaf thickness in rice,and provides a valuable genetic resource for molecular breeding of high-yielding rice through optimization of plant architecture.
基金funded by the National Natural Science Foundation of China(31871592)the Fundamental Research Funds for the Central Universities(2042022kf0015)+1 种基金the Creative Research Groups of the Natural Science Foundation of Hubei Province(2020CFA009)the Project for Technology Innovation of Hubei Province(2024BBA005).
文摘Leaf angle is a pivotal agronomic trait that significantly influences crop architecture and yield.Plant hormones,such as auxin,play a critical role in regulating leaf angle;however,the underlying molecular mechanisms remain to be fully elucidated.Here,we reveal that the auxin response factor gene,OsARF12,which is highly expressed in the leaf lamina joint,negatively regulates rice(Oryza sativa L.)leaf angle via affecting shoot gravitropism.Overexpression lines of OsARF12 exhibit more erect leaf angles,while the osarf12 mutants display enlarged leaf angles compared to the wild type.Further studies demonstrate that OsARF12 directly activates the expression of Loose Plant Architecture1(LPA1)and LAZY1 by binding to their promoters.The osarf12 mutant presents impaired shoot gravitropism,a phenotype consistent with that of the lpa1 and lazy1 mutants.Collectively,we elucidate the biological functions of OsARF12,which modulates leaf angle through its impact on shoot gravitropism by regulating the expression levels of LPA1 and LAZY1.This study provides insight into the role of auxin in determining rice leaf angle,potentially holding profound effects for the optimization of crop architecture.
文摘The high hydrophilicity of pineapple leaf fibres(PALF)limits their use in cement-and gypsum-based composites exposed to moisture.This study evaluates,for the first time,the combined effect of palm kernel oil and beeswax on the hygroscopic resistance and mechanical stability of PALF.The fibres were functionalised with three formulations(oil,wax,and a 1:2 oil/wax blend)applied at different mass ratios(CR=0.5-2).Treatments increased the average bundle diameter by up to+46%(238μm)and reduced density down to 1.06 g/cm^(3).Hygroscopically,water absorption decreased from 202.4%(raw fibres)to 76.3%(CR=2),representing a maximum reduction of 59.4%in saline medium,while moisture regain dropped from 27.9%to 14.6%(−47.7%).The oil/wax blend proved most effective,simultaneously reducing water absorption(−51.2%)and moisture regain(−46.8%)at CR=1.Mechanically,the fibres retained tensile strength(415.2 vs.460.8 MPa,+11%at CR=1)and exhibited enhanced ductility(+62.5%,with elongation at break increasing from 1.6%to 2.6%),without significantly altering Young’s modulus(12.3 to 10 GPa).Water absorption kinetics were accurately described by the Czel and Mohsenin models(R^(2)>0.98).These findings clearly demonstrate that bio-based lipid coatings can provide an eco-friendly alternative to conventional chemical treatments.They improve hygroscopic resistance and preserve mechanical integrity of PALF,providing original quantitative data for their integration into durable cement-and gypsum-based composites subjected to humid or cyclic wet-dry conditions.
基金supported by the Scientific Research Foundation supported by Yunnan Agricultural University(A3012024035044)International Cooperation and Exchange of the National Natural Science Foundation of China(No.42361144885).
文摘The establishment of plantations has become a critical approach for reducing greenhouse gas emissions,particularly in fragile environments with carbon sequestration potential.In karst areas,plantations based on fastgrowing afforestation species made significant contributions to enhancing carbon sequestration.However,the impact of understory vegetation on carbon accumulation remains unclear.Especially,the carbon accumulation associated with litter produced during the replacement of understory species receives insufficient attention,which leads to the neglect of the carbon sequestration potential in plantations of karst areas.Leaf is a crucial organ that links the litter production.To explore how leaf traits adapt to competitive environments and drive litter carbon accumulation during understory species replacement,this study observed leaf traits and litter carbon content changes in three types of plantations in the Liujiang River Basin,a typical karst area.A total of 37 sampling plots were selected for field investigation over a twoyear period.Leaf traits,species diversity,vegetation coverage,and litter carbon characteristics in understory vegetation were measured.Variance analysis,allometric equations,and path analysis were used for data analysis.The results showed that most understory species adopted a biomass conservation strategy under high-coverage conditions(>44.27%)and expanded competitive leaf area under low-coverage conditions(<44.27%).However,Bidens pilosa and Miscanthus floridulus exhibited strong competitiveness during understory species replacement.They showed an expansion of competitive leaf area under high-coverage conditions.This competitive strategy reduced species diversity and community specific leaf area.But the rapid expansion of Bidens pilosa and Miscanthus floridulus increased understory vegetation coverage,and their increased specific leaf area facilitated leaf shedding,resulting in significant litter weight accumulation(P<0.05),thereby enhancing litter carbon content per unit area.These competitive strategies were key driving factors for the increase in litter carbon content per square meter,which reached a maximum of 49.6% higher than that in natural grasslands.And the maximum increase in litter carbon accumulation derived from understory vegetation reached 3.37 times from 2023 to 2024 in plantations.In the understory vegetation of plantations,the competitive strategies reflected by leaf adaptation of key competitive species are critical factors influencing litter carbon accumulation.Future research could deeply explore the carbon sequestration effects resulting from the dynamic changes in competition within the understory vegetation of plantations.
基金supported by the National Natural Science Foundation of China(32460329)the Bintuan Science&Technology Program(2024AB075)to L.H+2 种基金the National Natural Science Foundation of China(32360279)an open program from the Key Laboratory of Protection and Utilization of Biological Resources in the Tarim Basin(BRZD2004)a provincial talentintroduction program of Xinjiang Uygur Autonomous Region to D.H.
文摘The trade-off between leaf size and leafing intensity(i.e.,the number of leaves per unit stem size)is a key axis of trait covariation across the diversity of plant foliage deployment.However,the functional significance of leafing intensity and its possible combinations with leaf size in dealing with water limitation remains unclear.Using Populus euphratica as an illustrative tree species growing in hyper-arid climates,we investigated how leaf size and leafing intensity co-varied under varying water stresses.In the Ebinor lowlands and the upper reaches of the Tarim River(NW China),we sampled>1800 current-year twigs from 505 trees across 14 sites along a climatic gradient characterized by precipitation,potential evapotranspiration and vapor pressure deficit.Leafing intensity based on stem mass(LIM)decreased with climatic aridity,primarily due to greater stem mass,but not fewer leaves.This indicates a higher investment in structural support for leaf attachment under water stress.Both leaf area and mass decreased with LIM at a lower-than-proportional rate,with the decrease in leaf size being more pronounced under drier climates.This suggests that higher LIM incurs a high cost of reducing leaf size in water-limited habitats.These findings challenge the assumption that higher leafing intensity always confers an advantage ready for environmental stresses due to higher developmental flexibility offered by more axillary buds.Rather,we propose that a strategy of lower leafing intensity,with greater structural support for leaf attachment and less compromise in leaf size,can be advantageous under water limitation.
基金supported by the National Natural Science Foundation(32130068,32271634,and 32071597)CAS Key Laboratory of Forest Ecology and Silviculture,Institute of Applied Ecology,Chinese Academy of Sciences(KLFES-2025)。
文摘Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify TSEMF in response to environmental changes.However,there has been limited exploration of multitrait combinations for predicting TS-EMF across seasons and of trait thresholds that enhance TS-EMF.Here,for 10 dominant tree species in urban forests of Northeast China,14 traits were measured and four aboveground and three belowground ecological functions assessed in three seasons.Ecological functions and TS-EMF differed significantly throughout the seasons(P<0.05).Synergistic relationships were found between carbon sequestration and oxygen release,between cooling and humidification,and between organic carbon accumulation and nutrient cycling.Notably,aboveground multifunctionality played a leading role in TS-EMF.With seasonal changes,resource allocation shifted toward traits related to resource acquisition rather than conservation to maintain TS-EMF.The combination of traits that predicted TS-EMF varied by type,accounting for up to 66.45%of the variation.TS-EMF was primarily driven by leaf structure in spring and by nutrient accumulation in autumn.Leaf carbon content(LCC)consistently served as a stabilizing factor for predicting TS-EMF across seasons.At 36.5-36.8 mg g^(-1),LCC had its optimal effect on TS-EMF.Other traits in combination that positively influence total TS-EMF include leaf nitrogen content(3.43-3.45 mg g^(-1)),leaf phosphorus content(0.80-0.83 mg g^(-1)),and leaf area(65.86-68.43 cm^(2)).Within these specified trait thresholds,Morus alba and Quercus mongolica were identified as key species.These findings suggest that the trade-off between various ecological functions can be managed by altering plant traits across seasons.This approach could provide a theoretical foundation for enhancing the TS-EMF of urban forests through trait-based management,offering practical guidance for selecting tree species.
基金supported by National Natural Science Foundation of China(U23A20250)the earmarked fund for CARS(CARS-45)+2 种基金the National Key R&D Program of China(2023YFD2400600)Sichuan Provincial Science and Technology Innovation Talent Project(2023JDRC0043)Sichuan Innovation Team of National Modern Agricultural Industry Technology System(SCCXTD-2024-15)。
文摘Background As living standards improve,consumers are placing greater emphasis on the enhancement of fish flesh quality,making its improvement increasingly critical.Plant-derived polysaccharides positively affect the improvement of animal flesh quality.Panax ginseng leaf polysaccharides(PGLP)have a similar composition and lower cost compared with Panax ginseng root polysaccharides.However,its function and application effects in grass carp(Ctenopharyngodon idella)are unclear.Methods A total of 540 sub-adult grass carp(679±1.29 g),one of the important economic fish species,were used as experimental models and fed diets supplemented with 0,100,200,300,400,or 500 mg/kg PGLP for 60 d.After 60 d,grass carp were weighed,and their muscles were collected to explore the effects of PGLP on the growth and development of myofibers and energy metabolism-related parameters.Results Our study found that PGLP increased the growth performance and muscle nutritional composition as well as improved muscle hardness,springiness,cohesiveness,chewiness,and hyperplasia of myofibers of sub-adult grass carp.Besides,PGLP promoted muscle energy metabolism by increasing creatine,glycogen,pyruvate,and acetyl-CoA contents and creatine kinase(CK),pyruvate kinase(PK),phosphofructokinase(PFK),and hexokinase(HK)activities,while decreasing lactate dehydrogenase(LDH)activity and lactate content in fish muscle.Finally,our study found that PGLP enhanced mitochondrial function by increasing the protein expression of mitochondrial complexes I–V,biogenesis,and fusion and decreasing autophagy and fission in fish muscle.Conclusions PGLP improved growth performance and flesh quality of sub-adult grass carp,which may be related to enhancing hyperplasia of myofibers by promoting energy metabolism.We concluded that the recommended amount of PGLP in sub-adult grass carp feed to optimize growth performance is 100–200 mg/kg.This study provides a theoretical basis for the application of PGLP in fish feed and for the analysis of the mechanism of nutrition and feed regulating fish flesh quality,which is of great significance.
基金supported by the National Natural Science Foundation of China(Grant Nos.32201890 and 32272197)the Special Funds for Scientific and Technological Innovation of Jiangsu province,China(Grant Nos.BE2022425 and BK20220017)+1 种基金the National Key R&D Program of China(Grant No.2022YFD2301401)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China.
文摘Four modern hybrid and four japonica rice varieties differing in biomass,yield,and daily biomass production rate during the grain-filling period(DBPGF),were used to reveal the eco-physiological photosynthetic characteristics of high-yield and high-efficiency rice.Varietal differences were analyzed in leaf and canopy photosynthetic parameters,associated leaf morphological and anatomical traits(e.g.,stomatal density,vein density,mesophyll cell arrangement),as well as differences in canopy light interception and leaf area index,and their effects on yield and biomass accumulation.Hybrid rice with yield higher than 11.0 t/hm^(2) and DBPGF higher than 200 kg/(hm^(2)·d),and japonica rice with yield higher than 9.0 t/hm^(2) and DBPGF higher than 200 kg/(hm^(2)·d),were classified as high-yield and high-efficiency varieties;other varieties were considered general types.Based on this criterion,two hybrid(Yongyou 2640 and Shanyou 63)and two japonica varieties(Huaidao 5 and Nangeng 5718)were categorized as high-yield and high-efficiency types,while the remaining two hybrid(Liangyoupeijiu and C Liangyou 513)and two japonica varieties(Suxiu 867 and Yangnongdao 1)were classified as general types.Results indicated that high-yield and high-efficiency varieties generally have higher leaf and canopy photosynthesis,superior leaf stomatal,vascular,and mesophyll structures that facilitate CO_(2)diffusion and hydraulic transport,higher canopy light transmittance,and slower leaf area attenuation.Rice yield and biomass were positively correlated with photosynthetic parameters and closely linked to associated photosynthetic traits.Efficient rice production was attributed to coordinated improvements in leaf structure,canopy architecture,and delayed leaf area attenuation.This study provides important theoretical guidance for breeding high-efficiency rice varieties.
基金Supported by the Green Plant Protection Project of Heilongjiang Province(2130108)Key R&D Program Project of Heilongjiang Province(2023ZX02B0502)Heilongjiang Province Rice Modern Agriculture Industry Technology Collaborative Innovation System Project(2025)。
文摘To ascertain the genetic diversity of gray leaf spot pathogen on Dictamnus dasycarpus popoulation in Heilongjiang Province,a total of 57 strains of Paracercospora dictamnicola were isolated and purified from the diseased samples collected from five Chinese herbal medicine planting areas in Heilongjiang Province between the years of 2021 and 2022.Repetitive extragenic palindromic polymerase chain reaction(Rep–PCR)was used to amplify 57 isolates of gray leaf spot pathogen on D.dasycarpus from different regions of Heilongjiang Province.The polymorphic bands amplified by three sets of primers accounted for more than 80%.Cluster analysis results showed that at a similarity coefficient of 0.67,the gray leaf spot pathogen on D.dasycarpus in Heilongjiang Province could be divided into five major genetic groups.Genetic diversity parameter analysis indicated that there were certain differences in genetic richness among the geographic populations of gray leaf spot pathogen on D.dasycarpus from different regions.Analysis of molecular variance(AMOVA)revealed that genetic variation among strains mainly originated within populations.The genetic differentiation and relationships of gray leaf spot pathogen on D.dasycarpus from different geographic regions of Heilongjiang Province indicated that genetic differentiation and kinship among populations were somewhat related to their geographic distance.The greater the geographic distance,the higher the genetic differentiation coefficient,and the lower the genetic uniformity among populations.
基金Supported by Key Technique Research on Middle and Low Yield Paddy Field Improvement in Jilin Middle Part(20096026)~~
文摘[Objective] To provide scientific basis for high phosphorus efficiency cultivation and regulation of rice. [Method] Changbai9 （CB9） and Jijing81 （JJ81） were used as experimental materials for pot experiment, and five levels of phosphorus nutrient （ Po - P4 ） were set for each variety, the net photosynthesis rate, Chlorophyll Meter Readings （SPAD Readings）, stomatal conductance, transpiration rate, intercellular CO2 concentration, and stomatal limitation were observed and compared between five different phosphorus levels at filling stage. [ Result] The net photosynthesis rate of CB9 reached the highest at P3, and was significantly different from other treatments （P 〈0.05）;the net photosynthesis rate of groups with phosphorus of J J81 were higher than that of the control group,and reached the highest at P,. The SPAD Readings of CB9 and JJ81 all achieved the highest at P3, and stomatal conductance and transpiration rate were all at first increased then decreased with the phosphor- us increased in CB9 and JJ81. With the phosphorus increased, intercellular CO2 concentration of CB9 decreased at first and then increased, while in JJ81 the trend was inversed,but the tendency of intercellular CO2 concentration were opposite to that of stomatal limitation in both culti- vars. [ Conclusion] Appropriate adding phosphorus could improve photosynthetic characteristic of rice flag-leaf,but displayed significant genotypic difference.
文摘The changes in photochemical features of Photosystem Ⅱ (PS Ⅱ) and contents of Rubisco large subunit (RLS) and small subunit (RSS) in flag leaf from 75DAS to 113DAS (from filling to harvesting stages) were investigated in two hybrid rices (Oryza sativa L) cv. Liangyoupeijiu and cv. Shanyou 63 grown in the field. Liangyoupeijiu is a super high-yielding rice and Shanyou 63 has widely been planted in China in these years. The results indicate that soluble protein and chlorophyll in both cultivars degraded slowly at first and dramatically thereafter. The degradation speed of soluble protein in Shanyou 63 was faster than that in Liangyoupeijiu. Both Fv/Fm and qP decreased in parallel with leaf senescence, whereas qN fell at first and then rose. No significant change in excitation pressure (1-qP) was found before 89DAS but a sharply increase in both cultivars after it occurred. Excitation pressure rose more rapidly in Shanyou 63 than that in Liangyoupeijiu. The changes of RLS and RSS content exhibited the same trend as that of soluble protein content. A better linear correlation between RLS, RSS degradation and elevation of (1-qP) were shown in both cultivars. We suggest that the increase in PSⅡ excitation pressure possibly induced the quick senescence process in rice flag leaf. The high-yielding of Liangyoupeijiu may be due to its maintenance of stronger photosynthetic capacity, longer and more stable photosynthetic functional du-ration than that of Shanyou 63.
基金Supported by National Natural Science Foundation of China (50875131)~~
文摘[Objective] The aim was to conduct non-destructive monitoring on wheat leaf in field and discuss the method to measure geometric phenotype of flag leaf through digital image processing in order to establish relationship between geometric pheno- type of flag leaf and N fertilizer regulation. [Method] Ningmai 13 was applied with N fertilizers in different amounts to discuss relationship among area, length, average width of flag leaf and applied N fertilizers using digital camera and digital image pro- cessing technique. [Result] Fertilizer is a main environmental factor influencing geo- metric phenotype of flag leaf, for example, area of flag leaf would enlarge four times and the length would increase from 15.87 to 25.33 cm by different N fertilizer amount. Thus, geometric phenotype of flag leaf would reflect N fertilizer amount at early stage. The highly accurate relationship between phenotype and N fertilizer is a reliable tech- nique to study on rules of wheat phenotype, N fertilizer and environmental factors. [Conclusion] The research indicated that digital image processing technique with scale label and dynamic background plates is an effective method to obtain geometric phenotype of sessile crops and crops with little leaf, providing a feasible scheme for non- destructive monitoring on growth dynamic of leaf＇s organs.
基金supported by the National Natural Science Foundation of China (No. 30630047) the Project on Absorption of Intellects by Institutions of Higher Education for Academic Disciplinary Innova-tions (the 111 Project) (No. B06014), China
文摘To understand genetic patterns of the morphological and physiological traits in flag leaf of barley, a double haploid （DH） population derived from the parents Yerong and Franklin was used to determine quantitative trait loci （QTL） controlling length, width, length/width, and chlorophyll content of flag leaves. A total of 9 QTLs showing significantly additive effect were detected in 8 intervals on 5 chromosomes. The variation of individual QTL ranged from 1.9% to 20.2%. For chlorophyll content expressed as SPAD value, 4 QTLs were identified on chromosomes 2H, 3H and 6H; for leaf length and width, 2 QTLs located on chromosomes 5H and 7H, and 2 QTLs located on chromosome 5H were detected; and for length/width, I QTL was detected on chromosome 7H. The identification of these QTLs associated with the properties of flag leaf is useful for barley improvement in breeding programs.
基金the National Key Research and Development Program of China (2017YFD0301001 and 2016YFD0300403)the National Basic Research Program of China (2015CB150404)the Shandong Province Mount Tai Industrial Talents Program
文摘Premature senescence after anthesis reduces crop yields.Delaying leaf senescence could maintain photosynthetic activity for a longer period and lead to a higher photosynthetic rate.Recent studies have provided some insights into the interaction between cytokinin and nitrogen(N)in the regulation of plant development.In the present study,foliar application of exogenous 6-benzylaminopurine(6-BA)and lovastatin,an inhibitor of cytokinin synthesis,was combined with three N rates[0 kg ha^(-1)(low nitrogen,LN),240 kg ha^(-1)(normal nitrogen,NN),and 360 kg ha^(-1)(high nitrogen,HN)]in two wheat cultivars,Wennong 6(with a staygreen phenotype)and Jimai 20(with a non-staygreen phenotype).Flag leaf senescence was assessed using a Gompertz growth curve.Grain mass,dry matter accumulation and distribution,total N of flag leaf,and concentrations of zeatin riboside(ZR)and abscisic acid(ABA)were also used to evaluate the functional characteristics of flag leaves.Grain mass was negatively correlated with initial senescence rate(r_0)and duration of rapid chlorophyll loss(Chl_(loss)),whereas it was positively correlated with maximum senescence rate(r_(max)),average senescence rate(r_(aver)),persistence phase(Chl_(per)),total duration of flag leaf(Chl_(total))and inflection point cumulative temperature(M).Compared to Jimai 20,Wennong 6 had larger r_(aver),Chl_(per),and Chl_(total).The concentration of ZR was highest under the 6-BA×NN treatment,followed by the 6-BA×HN and 6-BA×LN treatments.However,the concentration of ABA showed the opposite trend.It was concluded that the staygreen phenotype Wennong 6 was associated with greater grain mass and altered cytokinin metabolism and could be classified as a functional staygreen type.Foliar application of 6-BA interacting with N at the NN level(240 kg ha^(-1))may be a beneficial strategy for improving grain yield of wheat by regulating endogenous hormones and the flag leaf senescence process.Increasing endogenous cytokinin promoted the transport of dry matter to grain.
基金funded by the National Key R&D Program of China(2017YFD0300906)the National Key Technologies R&D Program of China during the 12th Five-Year Plan period(2012BAD04B06)。
文摘In order to identify the optimum period of spring water-restrictive irrigation for winter wheat(Triticum aestivum L.)in the Haihe Plain,China and elucidate its effects on flag leaf senescence and yield formation,field experiments were conducted at the Xinji Experimental Station of Hebei Agricultural University from 2016 to 2019 by using different irrigation regimes in spring,including the conventional regime involving two irrigation periods(control(CK),the 3-leaf unfolding stage and the anthesis stage)and a series of single,restrictive irrigation regimes(SRI)comprising irrigation at the 3-leaf unfolding stage(3 LI),4 LI,5 LI,and 6 LI.There are five major findings:(1)The senescence(determined by the green leaf area,GLA)in the 4 LI treatment occurred moderately earlier than that in CK,showed no significant difference with that in 5 LI and 6 LI,and occurred significantly later than that in 3 LI.(2)Compared with other SRI treatments,the GLA value and photosynthetic rate in 4 LI were 14.82 and 20.1%higher,respectively.Microstructural analysis of flag leaf also revealed that the mesophyll cells and chloroplasts were irregularly arranged under drought stress in 3 LI and 6 LI;however,drought stress had minimal negative effects on the microstructure in 4 LI and 5 LI.(3)Postponed irrigation in spring could significantly increase superoxide dismutase(SOD)and catalase(CAT)activities in the early stage of grain filling;however,these activities would subsequently decrease.Among the four SRI treatments,the overall enzyme activities were the highest in 4 LI,and the combined malondialdehyde(MDA)content in flag leaves in 4 LI and 5 LI was 14.5%lower on average than that in 3 LI and 6 LI.(4)The soluble sugar(SS)and proline(Pro)contents in 4 LI were the highest among the four SRI treatments;however,they were lower than those in CK.The abscisic acid(ABA)hormone content in 4 LI and 5 LI was lower than that in 3 LI and 6 LI,respectively,suggesting a smaller drought stress effect in 4 LI and 5 LI.(5)In two growing seasons,there was a larger number of spikes per unit area in 4 LI(i.e.,13.4%higher than that in 5 LI and 6 LI)and the 1000-grain weight in 4 LI was the highest among the four SRI treatments(i.e.,6.0%higher than that in the other three SRI treatments).Therefore,a single restrictive irrigation regime at the 4-leaf unfolding stage is recommended to be effective in slowing down the senescence process of flag leaves and achieving high yield.
基金supported by the Agricultural Science and Technology Achievement Transformation Fund of Science and Technology Ministry of China(Grant No. 2010GB2B000077)the Special Fund forAgro-scientific Research in the Public Interest of theministry of Agriculture of China (Grant No.201203026)
文摘The response of transcription factor genes to low nitrogen stress was studied to provide molecular basis for improving the absorption and utilization efficiency of nitrogen fertilizer in rice. The agilent rice genome arrays were used to study the varied expression of transcription factor genes in two rice varieties （SN 196 and Toyonishhiki） with different chlorophyll contents under low nitrogen stress. The results showed that a total of 53 transcription factor genes （35 down-regulated and 18 up-regulated genes at the transcription level） in flag leaves of super-green rice SN196 and 27 transcription factor genes （21 down-regulated and 6 up-regulated genes at the transcription level） in flag leaves of Toyonishiki were affected by low nitrogen stress. Among those nitrogen-responsive genes, 48 transcription factor genes in SN196 and 22 in Toyonishiki were variety-specific. There were overlapped transcription factor genes responded to low nitrogen stress between SN196 and Toyonishiki, with 1 up-regulated and 4 down-regulated at the transcription level. Distributions of low nitrogen responsive genes on chromosomes were different in two rice varieties.
基金supported by the National Key Research and Development Project of China(2022YFD1200700)the Crop Varietal Improvement and Insect Pests Control by Nuclear Radiation,Innovation Program of Chinese Academy of Agricultural Sciences,and the China Agriculture Research System(CARS-03).
文摘Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,je0407,with an 84.34%-89.35%smaller flag leaf angle compared with the wild type.The mutant also had an abnormal lamina joint and no ligule or auricle.Genetic analysis indicated that the ligule was controlled by two recessive genes,which were mapped to chromosomes 2AS and 2DL.The mutant allele on chromosome 2AS was named Tafla1b,and it was fine mapped to a 1 Mb physical interval.The mutant allele on chr.2DL was identified as Taspl8b,a novel allele of TaSPL8 with a missense mutation in the second exon,which was used to develop a cleaved amplified polymorphic sequence marker.F3 and F4 lines derived from crosses between Jing411 and je0407 were genotyped to investigate interactions between the Tafla1b and Taspl8b alleles.Plants with the Tafla1b/Taspl8a genotype had 58.41%-82.76%smaller flag leaf angles,6.4%-24.9%shorter spikes,and a greater spikelet density(0.382 more spikelets per cm)compared with the wild type.Plants with the Tafla1a/Taspl8b genotype had 52.62%-82.24%smaller flag leaf angles and no differences in plant height or spikelet density compared with the wild type.Tafla1b/Taspl8b plants produced erect leaves with an abnormal lamina joint.The two alleles had dosage effects on ligule formation and flag leaf angle,but no significant effect on thousand-grain weight.The mutant alleles provide novel resources for improvement of wheat plant architecture.
基金supported by the National High Technology Research and Development Program of China(Grant No. 2010AA101300)the Platform Construction for Science and Technology Basic Condition from Science and Technology Ministry,China (Grant No.505005)
文摘Genetic segregation analysis for flag leaf angle was conducted using six generations of P1, P2, F1, B1, B2 and F2 derived from a cross of 863B （a maintainer line of japonica rice） and A7444 （a germplasm with large flag leaf angle）. Genotypes and phenotypes of flag leaf angle were investigated in 863B （P1）, A7444 （P2） and 141 plants in BC^F~ （863BIA744411863B） population. An SSR genetic linkage map was constructed and QTLs for flag leaf angle were detected. The genetic map containing 79 information loci was constructed, which covers a total distance of 441.6 cM, averaging 5.6 cM between two neighboring loci. Results showed that the trait was controlled by two major genes plus polygene and the major genes were more important. Fifteen markers showed highly significant correlations with flag leaf angle based on single marker regression analysis. Two QTLs （qFLA2 and qFLA8） for flag leaf angle were detected by both composite interval method in software WinQTLCart 2.5 and composite interval method based on mixed linear model in QTL Network 2.0. The qFLA2 explained 10.50% and 13.28% of phenotypic variation, respectively, and was located at the interval of RM300 and RM145 on the short arm of chromosome 2. The qFLA8 explained 9.59% and 7.64% of phenotypic variation, respectively, and was located at the interval flanking RM6215 and RM8265 on the long arm of chromosome 8. The positive alleles at the two QTLs were both contributed from A7444.
基金funded by the Science and Technology Innovation Team Plan from Shaanxi Province,China (2014KCT25)projects supported by Cyrus Tang Foundation in Northwest A&F University,Yangling,Shaanxi Province,China
文摘Cuticular wax plays an important role in protecting land plant against biotic and abiotic stresses. Cuticular wax production on plant surface is often visualized by a characteristic glaucous appearance. This study identified quantitative trait loci （QTLs） for wheat （Triticum aestivum L.） flag leaf glaucousness （FLG） using a high-density genetic linkage map developed from a recombinant inbred line （RIL） population derived from the cross HeynexLakin by single-seed descent. The map consisted of 2 068 single nucleotide polymorphism （SNP） markers and 157 simple sequence repeat （SSR） markers on all 21 wheat chromosomes and covered a genetic distance of 2 381.19 cM, with an average marker interval of 1.07 cM. Two additive QTLs for FLG were identified on chromosomes 3AL and 2DS with the increasing FLG allele contributed from Lakin. The major QTL on 3AL, QFIg.hwwgr-3AL, explained 17.5-37.8% of the phenotypic variation in different environments. QFIg.hwwgr-3AL was located in a 4.4-cM interval on chromosome 3AL that was flanked by two markers IWA1831 and IWA8374. Another QTL for FLG on 2DS, designated as QFIg.hwwgr-2DS which was identified only in Yangling in 2014 （YL14）, was flanked by IWA1939 and Xgwm261 and accounted for 11.3% of the phenotypic variation for FLG. QFIg.hww- gr-3AL and QFIg.hwwgr-2DS showed Additive×Environment （AE） interactions, explaining 3.5 and 4.4% of the phenotypic variance, respectively. Our results indicated that different genes/QTLs may contribute different scores of FLG in a cultivar and that the environment may play a role in FLG.
