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
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
Understanding plant responses under low-pressure conditions is important for developing closed cultivation systems that simulate space environments.This study aimed to assess the effects of different pressure levels o...Understanding plant responses under low-pressure conditions is important for developing closed cultivation systems that simulate space environments.This study aimed to assess the effects of different pressure levels on growth,photosynthesis,and secondary metabolite accumulation in red leaf lettuce(Lactuca sativa L.var.‘Super Caesar’s Red’).Plants were cultivated for three weeks in sealed chambers under 101 kPa(atmospheric pressure),66 kPa(moderate low pressure),and 33 kPa(severe low pressure).Growth analysis showed that leaf length and leaf area decreased significantly with reduced pressure,while chlorophyll content and SPAD values increased gradually.Photosynthetic measurements indicated lower transpiration and stomatal conductance under low pressure relative to atmospheric conditions,consistent with reduced stomatal size and density observed by SEM.Secondary metabolite analysis showed strong induction of anthocyanins(41.3%at 66 kPa and 190.8%at 33 kPa),with significant increases in phenolic and flavonoid contents.Thus,low-pressure conditions may suppress morphological growth but promote secondary metabolite contents,offering potential advantages for quality-oriented cultivation strategies.This study provides fundamental insights into physiological adaptation under low pressure and practical implications for crop selection and management in space agriculture and other controlled environments.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
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
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
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
To understand the responses of flag leaf shape in rice to elevated CO2 environment and their genetic characteristics, quantitative trait loci （QTLs） for flag leaf shape in rice were mapped onto the molecular marker ...To understand the responses of flag leaf shape in rice to elevated CO2 environment and their genetic characteristics, quantitative trait loci （QTLs） for flag leaf shape in rice were mapped onto the molecular marker linkage map of chromosome segment substitution lines （CSSLs） derived from a cross between a japonica variety Asominori and an indica variety IR24 under free air carbon dioxide enrichment （FACE, 200 μmol/mol above current levels） and current CO2 concentration （Ambient, about 370 μmol/mol）. Three flag-leaf traits, flag-leaf length （LL）, width （LW） and the ratio of LL to LW （RLW）, were estimated for each CSSL and their parental varieties. The differences in LL, LW and RLW between parents and in LL and LW within IR24 between FACE and Ambient were significant at 1% level. The continuous distributions and transgressive segregations of LL, LW and RLW were also observed in CSSL population, showing that the three traits were quantitatively inherited under both FACE and Ambient. A total of 16 QTLs for the three traits were detected on chromosomes 1, 2, 3, 4, 6, 8 and 11 with LOD （Log10-1ikelihood ratio） scores ranging from 3.0 to 6.7. Among them, four QTLs （qLL-6＊, qLL-8＊ qLW-4＊ and qRLW-6＊） were commonly detected under both FACE and Ambient. Therefore, based on the different responses to elevated CO2 in comparison with current CO2 level, it can be suggested that the expressions of several QTLs associated with flag-leaf shape in rice could be induced by the high CO2 level.展开更多
The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to en...The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to environmental changes and nutrient availability.However,limited research has been conducted on long-term temporal leaf N:P variation over a range of temperature zones.Using long-term monitoring data from the Chinese Ecosystem Research Network(CERN),we investigated temporal changes in leaf N and P stoichiometry for 50 dominant tree species from 10 typical forest sites across temperate and subtropical regions,and identified the underlying mechanisms driving these changes.For both regions combined,leaf P concentration of the 50 dominant tree species decreased(20.6%),whereas leaf N:P increased(52.0%)from 2005 to 2020.Leaf P decreased and leaf N:P increased in 67% and 69% of the tree species,respectively.The leaf N:P increase was primarily driven by the tree species in eastern subtropical forests,where global change factors and soil nutrients explained 68% of leaf N:P variation.The P limitation exhibited by tree species in eastern subtropical forest ecosystems intensified over time,and elevated temperature and CO_(2) levels,coupled with decreased soil available P concentrations,appear to be the main factors driving long-term leaf N:P increases in these forests.Investigating long-term variations in soil nutrients together with global change factors will improve our understanding of the nutrient status of forest ecosystems in the context of global change and will support effective forest ecosystem management.展开更多
The width of rice leaves determines the size of the photosynthetic area.Optimizing rice leaf width can improve the photosynthetic rate,thereby increasing rice yield.In this study,a genome-wide association study(GWAS)w...The width of rice leaves determines the size of the photosynthetic area.Optimizing rice leaf width can improve the photosynthetic rate,thereby increasing rice yield.In this study,a genome-wide association study(GWAS)was conducted by 225 rice germplasm resources to explore the genetic basis of rice flag leaf width(FLW).We identified nine QTLs associated with FLW(qFLWs),with phenotypic contribution rates ranging from 3.17%to 14.37%.Near-isogenic lines(NILs)were developed for fine-mapping of qFLW11,and the function of FLW11 was further verified.We narrowed down q FLW11 to an 87-kb interval,which contains five genes.展开更多
DNA methylation plays important roles in regulating gene expression during development.However,little is known about the influence of DNA methylation on secondary metabolism during leaf development in the tea plant(Ca...DNA methylation plays important roles in regulating gene expression during development.However,little is known about the influence of DNA methylation on secondary metabolism during leaf development in the tea plant(Camellia sinensis).In this study,we combined the methylome,transcriptome,and metabolome to investigate the dynamic changes in DNA methylation and its potential regulatory roles in secondary metabolite biosynthesis.In this study,the level of genomic DNA methylation increased as leaf development progressed from tender to old leaf.It additionally exhibited a similar distribution across the genomic background at the two distinct developmental stages studied.Notably,integrated analysis of transcriptomic and methylomic data showed that DNA hypermethylation primarily occurred in genes of the phenylpropanoid,flavonoid,and terpenoid biosynthesis pathways.The effect of methylation on transcription of these secondary metabolite biosynthesis genes was dependent on the location of methylation(i.e.,in the promoter,gene or intergenic regions)and the sequence context(i.e.,CpG,CHG,or CHH).Changes in the content of catechins and terpenoids were consistent with the changes in gene transcription and the methylation state of structural genes,such as serine carboxypeptidase-like acyltransferases 1A(SCPL1A),leucoanthocyanidin reductase(LAR),and nerolidol synthase(NES).Our study provides valuable information for dissecting the effects of DNA methylation on regulation of genes involved in secondary metabolism during tea leaf development.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 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.+1 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).
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 Research Foundation(NRF)funded by the Korean government(MSIT)(No.RS-2024-00459463).
文摘Understanding plant responses under low-pressure conditions is important for developing closed cultivation systems that simulate space environments.This study aimed to assess the effects of different pressure levels on growth,photosynthesis,and secondary metabolite accumulation in red leaf lettuce(Lactuca sativa L.var.‘Super Caesar’s Red’).Plants were cultivated for three weeks in sealed chambers under 101 kPa(atmospheric pressure),66 kPa(moderate low pressure),and 33 kPa(severe low pressure).Growth analysis showed that leaf length and leaf area decreased significantly with reduced pressure,while chlorophyll content and SPAD values increased gradually.Photosynthetic measurements indicated lower transpiration and stomatal conductance under low pressure relative to atmospheric conditions,consistent with reduced stomatal size and density observed by SEM.Secondary metabolite analysis showed strong induction of anthocyanins(41.3%at 66 kPa and 190.8%at 33 kPa),with significant increases in phenolic and flavonoid contents.Thus,low-pressure conditions may suppress morphological growth but promote secondary metabolite contents,offering potential advantages for quality-oriented cultivation strategies.This study provides fundamental insights into physiological adaptation under low pressure and practical implications for crop selection and management in space agriculture and other controlled environments.
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 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.
基金The study was supported by the National Natural Science Foundation, China （Grant Nos. 30270800 and 40231003）
文摘To understand the responses of flag leaf shape in rice to elevated CO2 environment and their genetic characteristics, quantitative trait loci （QTLs） for flag leaf shape in rice were mapped onto the molecular marker linkage map of chromosome segment substitution lines （CSSLs） derived from a cross between a japonica variety Asominori and an indica variety IR24 under free air carbon dioxide enrichment （FACE, 200 μmol/mol above current levels） and current CO2 concentration （Ambient, about 370 μmol/mol）. Three flag-leaf traits, flag-leaf length （LL）, width （LW） and the ratio of LL to LW （RLW）, were estimated for each CSSL and their parental varieties. The differences in LL, LW and RLW between parents and in LL and LW within IR24 between FACE and Ambient were significant at 1% level. The continuous distributions and transgressive segregations of LL, LW and RLW were also observed in CSSL population, showing that the three traits were quantitatively inherited under both FACE and Ambient. A total of 16 QTLs for the three traits were detected on chromosomes 1, 2, 3, 4, 6, 8 and 11 with LOD （Log10-1ikelihood ratio） scores ranging from 3.0 to 6.7. Among them, four QTLs （qLL-6＊, qLL-8＊ qLW-4＊ and qRLW-6＊） were commonly detected under both FACE and Ambient. Therefore, based on the different responses to elevated CO2 in comparison with current CO2 level, it can be suggested that the expressions of several QTLs associated with flag-leaf shape in rice could be induced by the high CO2 level.
基金supported by the National Natural Science Foundation of China(No.42030509)the Special Project on National Science and Technology Basic Resources Investigation of China(No.2021FY100705).
文摘The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to environmental changes and nutrient availability.However,limited research has been conducted on long-term temporal leaf N:P variation over a range of temperature zones.Using long-term monitoring data from the Chinese Ecosystem Research Network(CERN),we investigated temporal changes in leaf N and P stoichiometry for 50 dominant tree species from 10 typical forest sites across temperate and subtropical regions,and identified the underlying mechanisms driving these changes.For both regions combined,leaf P concentration of the 50 dominant tree species decreased(20.6%),whereas leaf N:P increased(52.0%)from 2005 to 2020.Leaf P decreased and leaf N:P increased in 67% and 69% of the tree species,respectively.The leaf N:P increase was primarily driven by the tree species in eastern subtropical forests,where global change factors and soil nutrients explained 68% of leaf N:P variation.The P limitation exhibited by tree species in eastern subtropical forest ecosystems intensified over time,and elevated temperature and CO_(2) levels,coupled with decreased soil available P concentrations,appear to be the main factors driving long-term leaf N:P increases in these forests.Investigating long-term variations in soil nutrients together with global change factors will improve our understanding of the nutrient status of forest ecosystems in the context of global change and will support effective forest ecosystem management.
基金supported by the Zhejiang Provincial Natural Science Foundation,China(Grant No.LD24C130001)the National Natural Science Foundation of China(Grant Nos.W2412006 and 32372125)+3 种基金the Hainan Provincial Natural Science Foundation,China(Grant Nos.GHYF2025029 and YBXM2422)the Innovation Platform for Academicians of Hainan Province,China(Grant No.YSPTZX202502)the National Modern Agricultural Industry Technology System Project,China(Grant No.CARS-01-18)the Special Support Program of Chinese Academy of Agricultural Sciences(Grant Nos.NKYCLJ-C-2021-015 and CAAS-ZDRW202401)。
文摘The width of rice leaves determines the size of the photosynthetic area.Optimizing rice leaf width can improve the photosynthetic rate,thereby increasing rice yield.In this study,a genome-wide association study(GWAS)was conducted by 225 rice germplasm resources to explore the genetic basis of rice flag leaf width(FLW).We identified nine QTLs associated with FLW(qFLWs),with phenotypic contribution rates ranging from 3.17%to 14.37%.Near-isogenic lines(NILs)were developed for fine-mapping of qFLW11,and the function of FLW11 was further verified.We narrowed down q FLW11 to an 87-kb interval,which contains five genes.
基金supported by the Natural Science Foundation of Guangdong Province(Grant Nos.2022A1515111141 and 2023A1515010786)。
文摘DNA methylation plays important roles in regulating gene expression during development.However,little is known about the influence of DNA methylation on secondary metabolism during leaf development in the tea plant(Camellia sinensis).In this study,we combined the methylome,transcriptome,and metabolome to investigate the dynamic changes in DNA methylation and its potential regulatory roles in secondary metabolite biosynthesis.In this study,the level of genomic DNA methylation increased as leaf development progressed from tender to old leaf.It additionally exhibited a similar distribution across the genomic background at the two distinct developmental stages studied.Notably,integrated analysis of transcriptomic and methylomic data showed that DNA hypermethylation primarily occurred in genes of the phenylpropanoid,flavonoid,and terpenoid biosynthesis pathways.The effect of methylation on transcription of these secondary metabolite biosynthesis genes was dependent on the location of methylation(i.e.,in the promoter,gene or intergenic regions)and the sequence context(i.e.,CpG,CHG,or CHH).Changes in the content of catechins and terpenoids were consistent with the changes in gene transcription and the methylation state of structural genes,such as serine carboxypeptidase-like acyltransferases 1A(SCPL1A),leucoanthocyanidin reductase(LAR),and nerolidol synthase(NES).Our study provides valuable information for dissecting the effects of DNA methylation on regulation of genes involved in secondary metabolism during tea leaf development.
