Three varieties were employed as materials to study changes of photosynthetic traits under low-temperature stress. The results showed that Pn, Gs and Tr decreased under low-temperature treatment. Ci decreased under lo...Three varieties were employed as materials to study changes of photosynthetic traits under low-temperature stress. The results showed that Pn, Gs and Tr decreased under low-temperature treatment. Ci decreased under low-temperature treatment 18℃/9℃, and 16℃/7℃, and it decreased in earlier stage after increased under 14℃/5℃. WUE was increased in earlier stage and after stabilized. The order of the three varieties of cold resistance were Jinyu 5>Xingken 3>Jidan 198. They could make self-regulation through adjusting Gs, Tr, Ci and WUE.展开更多
Water deficit is one of the major limiting factors in vegetation recovery and reconstruction in the semi-arid area of loess hilly regions. Leaf photosynthesis in Hippophae rhamnoides Linn., a common tree grown in this...Water deficit is one of the major limiting factors in vegetation recovery and reconstruction in the semi-arid area of loess hilly regions. Leaf photosynthesis in Hippophae rhamnoides Linn., a common tree grown in this region, decreases under water stress, but the mechanism responsible is not clear. The objective of this study was to investigate the effects of drought stress on photosynthesis and the relationship between photosynthetic variables and soil water contents to help us better understand the photophysiological characteristics of H. rhamnoides under water stress and guide cultivation in the loess hilly region. Here,gas exchange, chlorophyll fluorescence and antioxidant enzyme activity in leaves of 3-year-old saplings of H.rhamnoides grown in pots were tested under eight soil water conditions. When soil water content(RWC) was between 38.9 and 70.5 %, stomatal limitation was responsible for the reduced net photosynthetic rate(PN).When RWC was lower than 38.9 %, nonstomatal limitation was the main factor restricting PN. Moderate water stress improved the water use efficiency(WUE) of the leaf.Water stress significantly influenced fluorescence variables and the antioxidant enzyme system. When RWC was between 38.9 and 70.5 %, nonphotochemical quenching(NPQ) increased and then decreased, indicating that thermal energy dissipation was a significant photoprotection mechanism. Antioxidant enzymes were activated when RWC ranged from 48.3 to 70.5 %; under severe water stress(RWC \ 38.9 %), the antioxidant enzyme system was damaged, the activity of the antioxidant enzymes declined, and membranes were damaged. In the semiarid loess hilly region, RWC between 58.6 and 70.5 % was the economic water threshold value that maintained higher WUE and PN, and the maximum soil water deficit level that could sustain H. rhamnoides was RWC of 38.9 %.展开更多
A two-year field experiment was conducted to measure the effects of densification methods on photosynthesis and yield of densely planted wheat.Inter-plant and inter-row distances were used to define ratefixed pattern(...A two-year field experiment was conducted to measure the effects of densification methods on photosynthesis and yield of densely planted wheat.Inter-plant and inter-row distances were used to define ratefixed pattern(RR)and row-fixed pattern(RS)density treatments.Meanwhile,four nitrogen(N)rates(0,144,192,and 240 kg N ha-1,termed N0,N144,N192,and N240)were applied with three densities(225,292.5,and 360×10^(4)plants ha^(-1),termed D225,D292.5,and D360).The wheat canopy was clipped into three equal vertical layers(top,middle,and bottom layers),and their chlorophyll density(Ch D)and photosynthetically active radiation interception(FIPAR)were measured.Results showed that the response of Ch D and FIPAR to N rate,density,and pattern varied with different layers.N rate,density,and pattern had significant interaction effects on Ch D.The maximum values of whole-canopy Ch D in the two seasons appeared in N240 combined with D292.5 and D360 under RR,respectively.Across two growing seasons,FIPAR values of RR were higher than those of RS by 29.37%for the top layer and 5.68%for the middle layer,while lower than those of RS by 20.62%for the bottom layer on average.With a low N supply(N0),grain yield was not significantly affected by density for both patterns.At N240,increasing density significantly increased yield under RR,but D360 of RS significantly decreased yield by 3.72%and 9.00%versus D225 in two seasons,respectively.With an appropriate and sufficient N application,RR increased the yield of densely planted wheat more than RS.Additionally,the maximum yield in two seasons appeared in the combination of D360 with N144 or N192 rather than of D225 with N240 under both patterns,suggesting that dense planting combined with an appropriate N-reduction application is feasible to increase photosynthesis capacity and yield.展开更多
To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native species.However,few studies have compared the photosynthetic dynamics between...To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native species.However,few studies have compared the photosynthetic dynamics between invasive and native species during light fluctuations.We compared photosynthetic induction,relaxation dynamics and leaf traits between the invasive species,Tithonia diversifolia and two native species,Clerodendrum bungei and Blumea balsamifera,in full-sun and shady habitats.The photosynthetic dynamics and leaf traits differed among species.T.diversifolia showed a slower induction speed and stomatal opening response but had higher average intrinsic water-use efficiency than the two native species in full-sun habitats.Thus,the slow induction response may be attributed to the longer stomatal length in T.diversifolia.Habitat had a significant effect on photosynthetic dynamics in T.diversifolia and B.balsamifera but not in C.bungei.In shady habitat,T.diversifolia had a faster photosynthetic induction response than in full-sun habitat,leading to a higher average stomatal conductance during photosynthetic induction in T.diversifolia than in the two native species.In contrast,B.balsamifera had a larger stomatal length and slower photosynthetic induction and relaxation response in shady habitat than in full-sun habitat,resulting in higher carbon gain during photosynthetic relaxation.Nevertheless,in both habitats,T.diversifolia had an overall higher carbon gain during light fluctuations than the two native species.Our results indicated that T.diversifolia can adopt more effective response strategies under fluctuating light environments to maximize carbon gain,which may contribute to its successful invasion.展开更多
The giant freshwater prawn Macrobrachium rosenbergii distributed from tropical to subtropical regions,is a warm-water species,and its survival temperature is 14-35°C,which greatly limits its culture cycle and cul...The giant freshwater prawn Macrobrachium rosenbergii distributed from tropical to subtropical regions,is a warm-water species,and its survival temperature is 14-35°C,which greatly limits its culture cycle and culture area in China.Therefore,it is urgent to cultivate a new high quality,high yield variety with improved cold-resistance,but the genetic parameters for cold-resistance traits are unknown in M.rosenbergii.In this study,the cold-resistance of adult M.rosenbergii populations was tested using the indoor artificial cooling method.Individuals were selected from 139 families of Shufeng G3 generation and cultured for 200 days.A linear mixed model was constructed by ASReml-R to evaluate the genetic parameters of the cold-resistance trait(cooling degree hours,CDH)and growth traits(body weight,BW,and body length,BL)based on the restricted maximum likelihood(REML)method.The results show that the heritability of CDH was low(0.12±0.05),while the growth traits(BW and BL)had low to moderate heritability,with 0.20±0.06 for BW and 0.06±0.04 for BL.The phenotypic and genetic correlation between BW and BL was significantly positive,but significantly negative phenotypic and genetic correlations were detected between CDH and BW and between CDH and BL.Furthermore,the analysis of the differences between cold-resistance and phenotypic traits showed that the female reproductive status,exoskeleton hardness and claw number of adult prawns had a great influence on the cold-resistance of M.rosenbergii(P<0.05),indicating that adults with claws and hard exoskeletons are preferred as parents in subsequent breeding selection.The present results can be attributed to the selection and breeding of a new cold-resistant variety of M.rosenbergii.展开更多
Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in...Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei seedlings.The canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following thin-ning.Thinning improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light environ-ment.Under the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral composition.P.bournei photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light environment.In a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal conductance.As a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of P.bournei seedlings,and a reduction increased light absorption and use capacity and height:diameter ratios.The growth advantage transformed from diameter to height,enabling seedlings to access more light.Our findings suggest that the regeneration of shade-tolerant species such as P.bournei could be enhanced if a targeted approach to thinning based on stand type was adopted.展开更多
Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinit...Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinity-drought stress poses a major threat to rice production.In this study,two salinity levels(NS,non-salinity;HS,high salinity)along with three drought treatments(CC,control condition;DJ,drought stress imposed at jointing;DH,drought stress imposed at heading)were performed to investigate their combined influences on leaf photosynthetic characteristics,biomass accumulation,and rice yield formation.Salinity,drought,and their combination led to a shortened growth period from heading to maturity,resulting in a reduced overall growth duration.Grain yield was reduced under both salinity and drought stress,with a more substantial reduction under the combined salinity-drought stress.The combined stress imposed at heading caused greater yield losses in rice compared with the stress imposed at jointing.Additionally,the combined salinity-drought stress induced greater decreases in shoot biomass accumulation from heading to maturity,as well as in shoot biomass and nonstructural carbohydrate(NSC)content in the stem at heading and maturity.However,it increased the harvest index and NSC remobilization reserve.Salinity and drought reduced the leaf area index and SPAD value of flag leaves and weakened the leaf photosynthetic characteristics as indicated by lower photosynthetic rates,transpiration rates,and stomatal conductance.These reductions were more pronounced under the combined stress.Salinity,drought,and especially their combination,decreased the activities of ascorbate peroxidase,catalase,and superoxide dismutase,while increasing the contents of malondialdehyde,hydrogen peroxide,and superoxide radical.Our results indicated a more significant yield loss in rice when subjected to combined salinity-drought stress.The individual and combined stresses of salinity and drought diminished antioxidant enzyme activities,inhibited leaf photosynthetic functions,accelerated leaf senescence,and subsequently lowered assimilate accumulation and grain yield.展开更多
Growth traits are among the most important economic traits in pigs and are regulated by polygenes with complex regulatory mechanisms.As the major indicators of growth performance,the backfat thickness(BFT),loin eye ar...Growth traits are among the most important economic traits in pigs and are regulated by polygenes with complex regulatory mechanisms.As the major indicators of growth performance,the backfat thickness(BFT),loin eye area(LEA),and days to 100 kg(D100)traits are commonly used to the genetics improvement in pigs.However,the available genetic markers for these traits are limited.To uncover novel loci and candidate genes associated with growth performance,we collected the phenotypic information of BFT,LEA,and D100 in 1,186 pigs and genotyped all these individuals using the Neogen GGP porcine 80K BeadChip.We performed a genome-wide association study(GWAS)using 4 statistical models,including mixed linear models(MLM),fixed and random model circulating probability unification(FarmCPU),settlement of MLM under progressively exclusive relationships(SUPER),Bayesian-information and linkage-disequilibrium Iteratively nested keyway(Blink),and identified 5,3,and 6 high-confidence single nucleotide polymorphisms(SNPs)associated with BFT,LEA,and D100,respectively.Variant annotation and quantitative trait locus(QTL)mapping analysis suggested that6 genes(SKAP2,SATB1,PDE7B,PPP1R16B,WNT3,and WNT9B)were potentially associated with growth performance in pigs.Transcriptome analysis suggested that the expression of Src Kinase Associated Phosphoprotein 2(SKAP2)was higher in prenatal muscles than in postnatal muscles,and the expression of Phosphodiesterase 7B(PDE7B)continuously increased during the prenatal stages and gradually decreased after birth,implying their potential roles in prenatal skeletal muscle development.Overall,this study provides new candidate loci and genes for the genetic improvement of pigs.展开更多
Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and...Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management practices.In this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of China.Photosynthetic capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were insignificant.However,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water content.Understory removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water availability.In general,thinning may be an appropriate management measure to promote P.massoniana WUE to cope with seasonal droughts under future extreme climates.展开更多
Cereal is an essential source of calories and protein for the global population.Accurately predicting cereal quality before harvest is highly desirable in order to optimise management for farmers,grading harvest and c...Cereal is an essential source of calories and protein for the global population.Accurately predicting cereal quality before harvest is highly desirable in order to optimise management for farmers,grading harvest and categorised storage for enterprises,future trading prices,and policy planning.The use of remote sensing data with extensive spatial coverage demonstrates some potential in predicting crop quality traits.Many studies have also proposed models and methods for predicting such traits based on multiplatform remote sensing data.In this paper,the key quality traits that are of interest to producers and consumers are introduced.The literature related to grain quality prediction was analyzed in detail,and a review was conducted on remote sensing platforms,commonly used methods,potential gaps,and future trends in crop quality prediction.This review recommends new research directions that go beyond the traditional methods and discusses grain quality retrieval and the associated challenges from the perspective of remote sensing data.展开更多
Photosynthesis is the most important biochemical reaction on Earth. It has co-evolved and developed with the Earth, driving the biogeochemical cycle of all elements on the planet and serving as the only chemical proce...Photosynthesis is the most important biochemical reaction on Earth. It has co-evolved and developed with the Earth, driving the biogeochemical cycle of all elements on the planet and serving as the only chemical process in nature that can convert light energy into chemical energy. Some heavy oxygen isotopic(^(18)O) labeling experiments have"conclusively" demonstrated that the oxygen released by photosynthesis comes only from water and are written into textbooks. However, it is not difficult to find that bicarbonate has never been excluded from the direct substrate of photosynthesis from beginning to end during the history of photosynthesis research. No convincing mechanism can be used to explain photosynthetic oxygen evolution solely from water photolysis. The bicarbonate effect, the Dole effect, the thermodynamic convenience of bicarbonate photolysis, the crystal structure characteristics of photosystem Ⅱ, and the reinterpretation of heavy oxygen isotopic labeling(^(18)O)experiments all indicate that the photosynthetic oxygen evolution does not exclude the important role and contribution of bicarbonate photolysis. The recently proposed view that bicarbonate photolysis is the premise of water photolysis, bicarbonate photolysis and water photolysis work together with a 1:1(mol/mol) stoichiometric relationship, and the stoichiometric relationship between oxygen and carbon dioxide released during photosynthetic oxygen evolution is also 1:1, has excellent applicability and objectivity, which can logically and reasonably explain the precise coordination between light and dark reactions during photosynthesis, the bicarbonate effect, the Dole effect, the Kok cycle and the neutrality of water and carbon in nature.This is of great significance for constructing the bionic artificial photosynthetic reactors and scientifically answering the question of the source of elemental stoichiometric relationships in nature.展开更多
The maintenance of sand-fixing vegetation is important for the stability of artificial sand-fixing systems in which seed dispersal plays a key role.Based on field wind tunnel experiments using 11 common plant species ...The maintenance of sand-fixing vegetation is important for the stability of artificial sand-fixing systems in which seed dispersal plays a key role.Based on field wind tunnel experiments using 11 common plant species on the southeastern edge of the Tengger Desert,China,we studied the secondary seed dispersal in the fixed and semi-fixed sand dunes as well as in the mobile dunes in order to understand the limitations of vegetation regeneration and the maintenance of its stability.Our results indicated that there were significant variations among the selected 11 plant species in the threshold of wind speed(TWS).The TWS of Caragana korshinskii was the highest among the 11 plant species,whereas that of Echinops gmelinii was the lowest.Seed morphological traits and underlying surface could generally explain the TWS.During the secondary seed dispersal processes,the proportions of seeds that did not disperse(no dispersal)and only dispersed over short distance(short-distance dispersal within the wind tunnel test section)were significantly higher than those of seeds that were buried(including lost seeds)and dispersed over long distance(long-distance dispersal beyond the wind tunnel test section).Compared with other habitats,the mobile dunes were the most difficult places for secondary seed dispersal.Buried seeds were the easiest to be found in the semi-fixed sand dunes,whereas fixed sand dunes were the best sites for seeds that dispersed over long distance.The results of linear mixed models showed that after controlling the dispersal distance,smaller and rounder seeds dispersed farther.Shape index and wind speed were the two significant influencing factors on the burial of seeds.The explanatory power of wind speed,underlying surface,and seed morphological traits on the seeds that did not disperse and dispersed over short distance was far greater than that on the seeds that were buried and dispersed over long distance,implying that the processes and mechanisms of burial and long-distance dispersal are more complex.In summary,most seeds in the study area either did not move,were buried,or dispersed over short distance,promoting local vegetation regeneration.展开更多
Soil salinization is the main factor that threatens the growth and development of plants and limits the increase of yield.It is of great significance to study the key soil environmental factors affecting plant root tr...Soil salinization is the main factor that threatens the growth and development of plants and limits the increase of yield.It is of great significance to study the key soil environmental factors affecting plant root traits to reveal the adaptation strategies of plants to saline-alkaline-stressed soil environments.In this study,the root biomass,root morphological parameters and root mineral nutrient content of two alfalfa cultivars with different sensitivities to alkaline stress were analyzed with black soil as the control group and the mixed saline-alkaline soil with a ratio of 7:3 between black soil and saline-alkaline soil as the saline-alkaline treatment group.At the same time,the correlation analysis of soil salinity indexes,soil nutrient indexes and the activities of key enzymes involved in soil carbon,nitrogen and phosphorus cycles was carried out.The results showed that compared with the control group,the pH,EC,and urease(URE)of the soil surrounding the roots of two alfalfa cultivars were significantly increased,while soil total nitrogen(TN),total phosphorus(TP),organic carbon(SOC),andα-glucosidase activity(AGC)were significantly decreased under saline-alkaline stress.There was no significant difference in root biomass and root morphological parameters of saline-alkaline tolerant cultivar GN under saline-alkaline stress.The number of root tips(RT),root surface area(RS)and root volume(RV)of AG were reduced by 61.16%,44.54%,and 45.31%,respectively,compared with control group.The ratios of K^(+)/Na^(+),Ca^(2+)/Na^(+)and Mg^(2+)/Na^(+)of GN were significantly higher than those of AG(p<0.05).The root fresh weight(RFW)and dry weight(RDW),root length(RL),RV and RT of alfalfa were positively regulated by soil SOC and TN,but negatively regulated by soil pH,EC,and URE(p<0.01).Root Ca^(2+)/Na+ratio was significantly positively correlated with soil TN,TP and SOC(p<0.01).The absorption of Mg and Ca ions in roots is significantly negatively regulated by soilβ-glucosidase activity(BGC)and acid phosphatase activity(APC)(p<0.05).This study improved knowledge of the relationship between root traits and soil environmental factors and offered a theoretical framework for elucidating how plant roots adapt to saline-alkaline stressed soil environments.展开更多
Investigating the role of Big Five personality traits in relation to various health outcomes has been extensively studied. The impact of “Big Five” on physical health is here explored for older Europeans with a focu...Investigating the role of Big Five personality traits in relation to various health outcomes has been extensively studied. The impact of “Big Five” on physical health is here explored for older Europeans with a focus on examining age groups differences. The study sample included 378,500 respondents derived from the seventh data wave of Survey of Health, Aging and Retirement in Europe (SHARE). The physical health status of older Europeans was estimated by constructing an index considering the combined effect of well-established health indicators such as the number of chronic diseases, mobility limitations, limitations with basic and instrumental activities of daily living, and self-perceived health. This index was used for an overall physical health assessment, for which the higher the score for an individual, the worst health level. Then, through a dichotomization process applied to the retrieved Principal Component Analysis scores, a two-group discrimination (good or bad health status) of SHARE participants was obtained as regards their physical health condition, allowing for further con-structing logistic regression models to assess the predictive significance of “Big Five” and their protective role for physical health. Results showed that neuroti-cism was the most significant predictor of physical health for all age groups un-der consideration, while extraversion, agreeableness and openness were not found to significantly affect the self-reported physical health levels of midlife adults aged 50 up to 64. Older adults aged 65 up to 79 were more prone to open-ness, whereas the oldest old individuals aged 80 up to 105 were mainly affected by openness and conscientiousness. .展开更多
A central goal of genetics is to understand the links between genetic variation and disease.Intuitively,one might expect diseasecausing variants to cluster into key pathways that drive disease etiology.But for complex...A central goal of genetics is to understand the links between genetic variation and disease.Intuitively,one might expect diseasecausing variants to cluster into key pathways that drive disease etiology.But for complex traits,association signals tend to be spread across most of the genome-including near many genes without an obvious connection to disease.展开更多
Tree peony is a unique traditional f lower in China,with large,fragrant,and colorful f lowers.However,a relatively short and concentrated f lowering period limits the applications and production of tree peony.A genome...Tree peony is a unique traditional f lower in China,with large,fragrant,and colorful f lowers.However,a relatively short and concentrated f lowering period limits the applications and production of tree peony.A genome-wide association study(GWAS)was conducted to accelerate molecular breeding for the improvement of f lowering phenology traits and ornamental phenotypes in tree peony.A diverse panel of 451 tree peony accessions was phenotyped for 23 f lowering phenology traits and 4 f loral agronomic traits over 3 years.Genotyping by sequencing(GBS)was used to obtain a large number of genome-wide single-nucleotide polymorphisms(SNPs)(107050)for the panel genotypes,and 1047 candidate genes were identified by association mapping.Eighty-two related genes were observed during at least 2 years for f lowering,and seven SNPs repeatedly identified for multiple f lowering phenology traits over multiple years were highly significantly associated with five genes known to regulate f lowering time.We validated the temporal expression profiles of these candidate genes and highlighted their possible roles in the regulation of f lower bud differentiation and f lowering time in tree peony.This study shows that GWAS based on GBS can be used to identify the genetic determinants of complex traits in tree peony.The results expand our understanding of f lowering time control in perennial woody plants.Identification of markers closely related to these f lowering phenology traits can be used in tree peony breeding programs for important agronomic traits.展开更多
Sweetpotato is an important crop that exhibits hexaploidy and high heterozygosity,which limits gene mining for important agronomic traits.Here,314 sweetpotato germplasm resources were deeply resequenced,and 4599509 SN...Sweetpotato is an important crop that exhibits hexaploidy and high heterozygosity,which limits gene mining for important agronomic traits.Here,314 sweetpotato germplasm resources were deeply resequenced,and 4599509 SNPs and 846654 InDels were generated,among which 196124 SNPs were nonsynonymous and 9690 InDels were frameshifted.Based on the Indels,genome-wide marker primers were designed,and 3219 of 40366 primer pairs were selected to construct the core InDel marker set.The molecular ID of 104 sweetpotato samples verified the availability of these primers.The sweetpotato population structures were then assessed through multiple approaches using SNPs,and diverse approaches demonstrated that population stratification was not obvious for most Chinese germplasm resources.As many as 20 important agronomic traits were evaluated,and a genome-wide association study was conducted on these traits.A total of 19 high-confidence loci were detected in both models.These loci included several candidate genes,such as IbMYB1,IbZEP1,and IbYABBY1,which might be involved in anthocyanin metabolism,carotenoid metabolism,and leaf morphogenesis,respectively.Among them,IbZEP1 and IbYABBY1 were first reported in sweetpotato.The variants in the promoter and the expression levels of IbZEP1 were significantly correlated with f lesh color(orange or not orange)in sweetpotato.The expression levels of IbYABBY1 were also correlated with leaf shape.These results will assist in genetic and breeding studies in sweetpotato.展开更多
To clarify the changes in plant photosynthesis and mechanisms underlying those responses to gradually increasing soil drought stress and reveal quantitative relationships between photosynthesis and soil moisture,soil ...To clarify the changes in plant photosynthesis and mechanisms underlying those responses to gradually increasing soil drought stress and reveal quantitative relationships between photosynthesis and soil moisture,soil water conditions were controlled in greenhouse pot experiments using 2-year-old seedlings of Forsythia suspensa(Thunb.) Vahl. Photosynthetic gas exchange and chlorophyll fluorescence variables were measured and analyzed under 13 gradients of soil water content. Net photosynthetic rate(PN), stomatal conductance(gs), and water-use efficiency(WUE) in the seedlings exhibited a clear threshold response to the relative soil water content(RSWC). The highest PNand WUEoccurred at RSWCof51.84 and 64.10%, respectively. Both PNand WUEwere higher than the average levels at 39.79% B RSWCB 73.04%. When RSWCdecreased from 51.84 to 37.52%,PN, gs, and the intercellular CO2 concentration(Ci)markedly decreased with increasing drought stress; the corresponding stomatal limitation(Ls) substantially increased, and nonphotochemical quenching(NPQ) also tended to increase, indicating that within this range of soil water content, excessive excitation energy was dispersed from photosystem II(PSII) in the form of heat, and the reduction in PNwas primarily due to stomatal limitation.While RSWCdecreased below 37.52%, there were significant decreases in the maximal quantum yield of PSII photochemistry(Fv/Fm) and the effective quantum yield of PSII photochemistry(UPSII), photochemical quenching(qP), and NPQ; in contrast, minimal fluorescence yield of the dark-adapted state(F0) increased markedly. Thus,the major limiting factor for the PNreduction changed to a nonstomatal limitation due to PSII damage. Therefore, an RSWCof 37.52% is the maximum allowable water deficit for the normal growth of seedlings of F. suspensa, and a water content lower than this level should be avoided in field soil water management. Water contents should be maintained in the range of 39.79% B RSWCB 73.04% to ensure normal function of the photosynthetic apparatus and high levels of photosynthesis and efficiency in F.suspensa.展开更多
Salinity is one of the major abiotic factors that limit the growth and productivity of plants.Foliar application of plant growth regulators(PGRs)may help plants ameliorate the negative impacts of salinity.Thus,a field...Salinity is one of the major abiotic factors that limit the growth and productivity of plants.Foliar application of plant growth regulators(PGRs)may help plants ameliorate the negative impacts of salinity.Thus,a field experiment was conducted at the Botanical Garden University of Balochistan,Quetta,to explore the potential role of PGRs,i.e.,moringa leaf extract(MLE;10%),proline(PRO;1μM),salicylic acid(SA;250μM),and thiourea(TU;10 mM)in ameliorating the impacts of salinity(120 mM)on Plantago ovata,an important medicinal plant.Salinity hampered plant photosynthetic pigments and metabolites but elevated oxidative parameters.However,foliar application of PGRs enhanced photosynthetic pigments,including Chl b(21.11%),carotenoids(57.87%)except Chl a,activated the defense mechanisms by restoring and enhancing the metabolites,i.e.,soluble sugars(49.68%),soluble phenolics(33.34%),and proline(31.47%),significantly under salinity stress.Furthermore,foliar supplementation of PGRs under salt stress led to a decrease of about 43.02%and 43.27%in hydrogen peroxide and malondialdehyde content,respectively.Thus,PGRs can be recommended for improved photosynthetic efficiency and metabolite content that can help to get better yield under salt stress,with the best and most effective treatments being those of PRO and MLE to predominately ameliorate the harsh impacts of salinity.展开更多
Ceiba species have high ornamental value and are widely cultivated in tropical regions.However,genetic background of cultivated Ceiba plants remains unclear.To understand the genetic relatedness of cultivated Ceiba pl...Ceiba species have high ornamental value and are widely cultivated in tropical regions.However,genetic background of cultivated Ceiba plants remains unclear.To understand the genetic relatedness of cultivated Ceiba plants and genetic basis of key horticultural traits,here we explored the genetic relatedness of 153 accessions of Ceiba plants cultivated in Southern China and identified SNPs associated with five horticultural traits,based on 11704 SNPs derived from double-digest restriction-site associated DNA sequencing(ddRAD-seq).Clustering analysis revealed that these accessions were composed of three groups:C.speciosa group,C.insignis group,and hybrid group.The GWAS identified two,four,two,three,and four SNPs related to petal color,petal striation number,flowering time,trunk shape,and prickles on the trunk and branches,respectively.One to two candidate genes were found near the SNPs strongly associated with these traits.This study revealed the genetic relatedness in the Ceiba plants cultivated in Southern China and presented the first GWAS analysis for five horticultural traits for them,laying a foundation for phenotype-related marker selection and molecular breeding.展开更多
基金Supported by the Science and Technology Foundation(2008BADB3B09-03)
文摘Three varieties were employed as materials to study changes of photosynthetic traits under low-temperature stress. The results showed that Pn, Gs and Tr decreased under low-temperature treatment. Ci decreased under low-temperature treatment 18℃/9℃, and 16℃/7℃, and it decreased in earlier stage after increased under 14℃/5℃. WUE was increased in earlier stage and after stabilized. The order of the three varieties of cold resistance were Jinyu 5>Xingken 3>Jidan 198. They could make self-regulation through adjusting Gs, Tr, Ci and WUE.
基金supported by Monitoring and Evaluation Report on Shandong Ecological Afforestation Program(SEAP)of The World Bank Loan(No.SEAP-JC-2)
文摘Water deficit is one of the major limiting factors in vegetation recovery and reconstruction in the semi-arid area of loess hilly regions. Leaf photosynthesis in Hippophae rhamnoides Linn., a common tree grown in this region, decreases under water stress, but the mechanism responsible is not clear. The objective of this study was to investigate the effects of drought stress on photosynthesis and the relationship between photosynthetic variables and soil water contents to help us better understand the photophysiological characteristics of H. rhamnoides under water stress and guide cultivation in the loess hilly region. Here,gas exchange, chlorophyll fluorescence and antioxidant enzyme activity in leaves of 3-year-old saplings of H.rhamnoides grown in pots were tested under eight soil water conditions. When soil water content(RWC) was between 38.9 and 70.5 %, stomatal limitation was responsible for the reduced net photosynthetic rate(PN).When RWC was lower than 38.9 %, nonstomatal limitation was the main factor restricting PN. Moderate water stress improved the water use efficiency(WUE) of the leaf.Water stress significantly influenced fluorescence variables and the antioxidant enzyme system. When RWC was between 38.9 and 70.5 %, nonphotochemical quenching(NPQ) increased and then decreased, indicating that thermal energy dissipation was a significant photoprotection mechanism. Antioxidant enzymes were activated when RWC ranged from 48.3 to 70.5 %; under severe water stress(RWC \ 38.9 %), the antioxidant enzyme system was damaged, the activity of the antioxidant enzymes declined, and membranes were damaged. In the semiarid loess hilly region, RWC between 58.6 and 70.5 % was the economic water threshold value that maintained higher WUE and PN, and the maximum soil water deficit level that could sustain H. rhamnoides was RWC of 38.9 %.
基金supported by the National Key Research and Development Program of China(2022YFD2301402)the National Natural Science Foundation of China(32071903)+2 种基金the Jiangsu Provincial Key Technologies R&D Program of China(BE2019386)the Guidance Foundation of the Sanya Institute of Nanjing Agricultural University,China(NAUSY2D01)the Earmarked Fund for Jiangsu Agricultural Industry Technology System(JATS(2022)468,JATS(2022)168)。
文摘A two-year field experiment was conducted to measure the effects of densification methods on photosynthesis and yield of densely planted wheat.Inter-plant and inter-row distances were used to define ratefixed pattern(RR)and row-fixed pattern(RS)density treatments.Meanwhile,four nitrogen(N)rates(0,144,192,and 240 kg N ha-1,termed N0,N144,N192,and N240)were applied with three densities(225,292.5,and 360×10^(4)plants ha^(-1),termed D225,D292.5,and D360).The wheat canopy was clipped into three equal vertical layers(top,middle,and bottom layers),and their chlorophyll density(Ch D)and photosynthetically active radiation interception(FIPAR)were measured.Results showed that the response of Ch D and FIPAR to N rate,density,and pattern varied with different layers.N rate,density,and pattern had significant interaction effects on Ch D.The maximum values of whole-canopy Ch D in the two seasons appeared in N240 combined with D292.5 and D360 under RR,respectively.Across two growing seasons,FIPAR values of RR were higher than those of RS by 29.37%for the top layer and 5.68%for the middle layer,while lower than those of RS by 20.62%for the bottom layer on average.With a low N supply(N0),grain yield was not significantly affected by density for both patterns.At N240,increasing density significantly increased yield under RR,but D360 of RS significantly decreased yield by 3.72%and 9.00%versus D225 in two seasons,respectively.With an appropriate and sufficient N application,RR increased the yield of densely planted wheat more than RS.Additionally,the maximum yield in two seasons appeared in the combination of D360 with N144 or N192 rather than of D225 with N240 under both patterns,suggesting that dense planting combined with an appropriate N-reduction application is feasible to increase photosynthesis capacity and yield.
基金financially supported by the National Natural Science Foundation of China(Grant number:32071661)。
文摘To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native species.However,few studies have compared the photosynthetic dynamics between invasive and native species during light fluctuations.We compared photosynthetic induction,relaxation dynamics and leaf traits between the invasive species,Tithonia diversifolia and two native species,Clerodendrum bungei and Blumea balsamifera,in full-sun and shady habitats.The photosynthetic dynamics and leaf traits differed among species.T.diversifolia showed a slower induction speed and stomatal opening response but had higher average intrinsic water-use efficiency than the two native species in full-sun habitats.Thus,the slow induction response may be attributed to the longer stomatal length in T.diversifolia.Habitat had a significant effect on photosynthetic dynamics in T.diversifolia and B.balsamifera but not in C.bungei.In shady habitat,T.diversifolia had a faster photosynthetic induction response than in full-sun habitat,leading to a higher average stomatal conductance during photosynthetic induction in T.diversifolia than in the two native species.In contrast,B.balsamifera had a larger stomatal length and slower photosynthetic induction and relaxation response in shady habitat than in full-sun habitat,resulting in higher carbon gain during photosynthetic relaxation.Nevertheless,in both habitats,T.diversifolia had an overall higher carbon gain during light fluctuations than the two native species.Our results indicated that T.diversifolia can adopt more effective response strategies under fluctuating light environments to maximize carbon gain,which may contribute to its successful invasion.
基金Supported by the Key Scientific and Technological Grant of Zhejiang for Breeding New Agricultural(Aquaculture)Varieties(No.2021C02069-4-3)the Major Research&Development Program(Modern Agriculture)of Jiangsu Province(No.BE2019352)+1 种基金the Earmarked Fund for the China Agriculture Research System(No.CARS-48)the Innovation Project of Postgraduate Scientific Research in Huzhou University in 2022(No.2022KYCX63)。
文摘The giant freshwater prawn Macrobrachium rosenbergii distributed from tropical to subtropical regions,is a warm-water species,and its survival temperature is 14-35°C,which greatly limits its culture cycle and culture area in China.Therefore,it is urgent to cultivate a new high quality,high yield variety with improved cold-resistance,but the genetic parameters for cold-resistance traits are unknown in M.rosenbergii.In this study,the cold-resistance of adult M.rosenbergii populations was tested using the indoor artificial cooling method.Individuals were selected from 139 families of Shufeng G3 generation and cultured for 200 days.A linear mixed model was constructed by ASReml-R to evaluate the genetic parameters of the cold-resistance trait(cooling degree hours,CDH)and growth traits(body weight,BW,and body length,BL)based on the restricted maximum likelihood(REML)method.The results show that the heritability of CDH was low(0.12±0.05),while the growth traits(BW and BL)had low to moderate heritability,with 0.20±0.06 for BW and 0.06±0.04 for BL.The phenotypic and genetic correlation between BW and BL was significantly positive,but significantly negative phenotypic and genetic correlations were detected between CDH and BW and between CDH and BL.Furthermore,the analysis of the differences between cold-resistance and phenotypic traits showed that the female reproductive status,exoskeleton hardness and claw number of adult prawns had a great influence on the cold-resistance of M.rosenbergii(P<0.05),indicating that adults with claws and hard exoskeletons are preferred as parents in subsequent breeding selection.The present results can be attributed to the selection and breeding of a new cold-resistant variety of M.rosenbergii.
基金This study was supported by the National Natural Science Foundation of China(Grant No.31870613)Guizhou Province High-level Innovative Talents Training Plan Project(2016)5661.
文摘Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei seedlings.The canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following thin-ning.Thinning improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light environ-ment.Under the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral composition.P.bournei photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light environment.In a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal conductance.As a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of P.bournei seedlings,and a reduction increased light absorption and use capacity and height:diameter ratios.The growth advantage transformed from diameter to height,enabling seedlings to access more light.Our findings suggest that the regeneration of shade-tolerant species such as P.bournei could be enhanced if a targeted approach to thinning based on stand type was adopted.
基金financed by the National Key Research and Development Program,China(Grant Nos.2022YFE0113400 and 2022YFD1500402)National Natural Science Foundation of China(Grant No.32001466)+3 种基金Scientific and Technological Innovation Fund of Carbon Emissions Peak and Neutrality of Jiangsu Provincial Department of Science and Technology,China(Grant Nos.BE2022304 and BE2022305)Joints Funds of the National Natural Science Foundation of China(Grant No.U20A2022)Postdoctoral Research Foundation of China(Grant No.2020M671628)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China.
文摘Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinity-drought stress poses a major threat to rice production.In this study,two salinity levels(NS,non-salinity;HS,high salinity)along with three drought treatments(CC,control condition;DJ,drought stress imposed at jointing;DH,drought stress imposed at heading)were performed to investigate their combined influences on leaf photosynthetic characteristics,biomass accumulation,and rice yield formation.Salinity,drought,and their combination led to a shortened growth period from heading to maturity,resulting in a reduced overall growth duration.Grain yield was reduced under both salinity and drought stress,with a more substantial reduction under the combined salinity-drought stress.The combined stress imposed at heading caused greater yield losses in rice compared with the stress imposed at jointing.Additionally,the combined salinity-drought stress induced greater decreases in shoot biomass accumulation from heading to maturity,as well as in shoot biomass and nonstructural carbohydrate(NSC)content in the stem at heading and maturity.However,it increased the harvest index and NSC remobilization reserve.Salinity and drought reduced the leaf area index and SPAD value of flag leaves and weakened the leaf photosynthetic characteristics as indicated by lower photosynthetic rates,transpiration rates,and stomatal conductance.These reductions were more pronounced under the combined stress.Salinity,drought,and especially their combination,decreased the activities of ascorbate peroxidase,catalase,and superoxide dismutase,while increasing the contents of malondialdehyde,hydrogen peroxide,and superoxide radical.Our results indicated a more significant yield loss in rice when subjected to combined salinity-drought stress.The individual and combined stresses of salinity and drought diminished antioxidant enzyme activities,inhibited leaf photosynthetic functions,accelerated leaf senescence,and subsequently lowered assimilate accumulation and grain yield.
基金supported by the National Natural Science Foundation of China(32172697,31830090,and 32002151)the Guangdong Provincial Natural Science Foundation,China(2021A1515011336)the Chinese Academy of Agricultural Sciences(CAAS-ZDRW202006)。
文摘Growth traits are among the most important economic traits in pigs and are regulated by polygenes with complex regulatory mechanisms.As the major indicators of growth performance,the backfat thickness(BFT),loin eye area(LEA),and days to 100 kg(D100)traits are commonly used to the genetics improvement in pigs.However,the available genetic markers for these traits are limited.To uncover novel loci and candidate genes associated with growth performance,we collected the phenotypic information of BFT,LEA,and D100 in 1,186 pigs and genotyped all these individuals using the Neogen GGP porcine 80K BeadChip.We performed a genome-wide association study(GWAS)using 4 statistical models,including mixed linear models(MLM),fixed and random model circulating probability unification(FarmCPU),settlement of MLM under progressively exclusive relationships(SUPER),Bayesian-information and linkage-disequilibrium Iteratively nested keyway(Blink),and identified 5,3,and 6 high-confidence single nucleotide polymorphisms(SNPs)associated with BFT,LEA,and D100,respectively.Variant annotation and quantitative trait locus(QTL)mapping analysis suggested that6 genes(SKAP2,SATB1,PDE7B,PPP1R16B,WNT3,and WNT9B)were potentially associated with growth performance in pigs.Transcriptome analysis suggested that the expression of Src Kinase Associated Phosphoprotein 2(SKAP2)was higher in prenatal muscles than in postnatal muscles,and the expression of Phosphodiesterase 7B(PDE7B)continuously increased during the prenatal stages and gradually decreased after birth,implying their potential roles in prenatal skeletal muscle development.Overall,this study provides new candidate loci and genes for the genetic improvement of pigs.
基金supported by the National Key Research and Development Program of China(2016YFD0600201)the National Nonprofit Institute Research Grant of CAF(CAFYBB2017ZB003)+1 种基金the National Natural Science Foundation of China(3187071631670720)。
文摘Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management practices.In this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of China.Photosynthetic capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were insignificant.However,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water content.Understory removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water availability.In general,thinning may be an appropriate management measure to promote P.massoniana WUE to cope with seasonal droughts under future extreme climates.
基金This study was supported by the National Natural Science Foundation of China(42271396)the Natural Science Foundation of Shandong Province(ZR2022MD017)+1 种基金the Key R&D Project of Hebei Province(22326406D)The European Space Agency(ESA)and Ministry of Science and Technology of China(MOST)Dragon(57457).
文摘Cereal is an essential source of calories and protein for the global population.Accurately predicting cereal quality before harvest is highly desirable in order to optimise management for farmers,grading harvest and categorised storage for enterprises,future trading prices,and policy planning.The use of remote sensing data with extensive spatial coverage demonstrates some potential in predicting crop quality traits.Many studies have also proposed models and methods for predicting such traits based on multiplatform remote sensing data.In this paper,the key quality traits that are of interest to producers and consumers are introduced.The literature related to grain quality prediction was analyzed in detail,and a review was conducted on remote sensing platforms,commonly used methods,potential gaps,and future trends in crop quality prediction.This review recommends new research directions that go beyond the traditional methods and discusses grain quality retrieval and the associated challenges from the perspective of remote sensing data.
基金the Support Plan Projects of Science and Technology Department of Guizhou Province [No.(2021)YB453]。
文摘Photosynthesis is the most important biochemical reaction on Earth. It has co-evolved and developed with the Earth, driving the biogeochemical cycle of all elements on the planet and serving as the only chemical process in nature that can convert light energy into chemical energy. Some heavy oxygen isotopic(^(18)O) labeling experiments have"conclusively" demonstrated that the oxygen released by photosynthesis comes only from water and are written into textbooks. However, it is not difficult to find that bicarbonate has never been excluded from the direct substrate of photosynthesis from beginning to end during the history of photosynthesis research. No convincing mechanism can be used to explain photosynthetic oxygen evolution solely from water photolysis. The bicarbonate effect, the Dole effect, the thermodynamic convenience of bicarbonate photolysis, the crystal structure characteristics of photosystem Ⅱ, and the reinterpretation of heavy oxygen isotopic labeling(^(18)O)experiments all indicate that the photosynthetic oxygen evolution does not exclude the important role and contribution of bicarbonate photolysis. The recently proposed view that bicarbonate photolysis is the premise of water photolysis, bicarbonate photolysis and water photolysis work together with a 1:1(mol/mol) stoichiometric relationship, and the stoichiometric relationship between oxygen and carbon dioxide released during photosynthetic oxygen evolution is also 1:1, has excellent applicability and objectivity, which can logically and reasonably explain the precise coordination between light and dark reactions during photosynthesis, the bicarbonate effect, the Dole effect, the Kok cycle and the neutrality of water and carbon in nature.This is of great significance for constructing the bionic artificial photosynthetic reactors and scientifically answering the question of the source of elemental stoichiometric relationships in nature.
基金supported by the Key R&D Program of Ningxia Hui Autonomous Region,China(2021BEG03008)the Natural Science Foundation of Ningxia Hui Autonomous Region,China(2021AAC03083).
文摘The maintenance of sand-fixing vegetation is important for the stability of artificial sand-fixing systems in which seed dispersal plays a key role.Based on field wind tunnel experiments using 11 common plant species on the southeastern edge of the Tengger Desert,China,we studied the secondary seed dispersal in the fixed and semi-fixed sand dunes as well as in the mobile dunes in order to understand the limitations of vegetation regeneration and the maintenance of its stability.Our results indicated that there were significant variations among the selected 11 plant species in the threshold of wind speed(TWS).The TWS of Caragana korshinskii was the highest among the 11 plant species,whereas that of Echinops gmelinii was the lowest.Seed morphological traits and underlying surface could generally explain the TWS.During the secondary seed dispersal processes,the proportions of seeds that did not disperse(no dispersal)and only dispersed over short distance(short-distance dispersal within the wind tunnel test section)were significantly higher than those of seeds that were buried(including lost seeds)and dispersed over long distance(long-distance dispersal beyond the wind tunnel test section).Compared with other habitats,the mobile dunes were the most difficult places for secondary seed dispersal.Buried seeds were the easiest to be found in the semi-fixed sand dunes,whereas fixed sand dunes were the best sites for seeds that dispersed over long distance.The results of linear mixed models showed that after controlling the dispersal distance,smaller and rounder seeds dispersed farther.Shape index and wind speed were the two significant influencing factors on the burial of seeds.The explanatory power of wind speed,underlying surface,and seed morphological traits on the seeds that did not disperse and dispersed over short distance was far greater than that on the seeds that were buried and dispersed over long distance,implying that the processes and mechanisms of burial and long-distance dispersal are more complex.In summary,most seeds in the study area either did not move,were buried,or dispersed over short distance,promoting local vegetation regeneration.
基金the Agricultural Science and Technology Innovation Project of Jilin Province(Postdoctoral Fund Project)(CXGC2021RCB007)Agricultural Science and Technology Innovation Project of Jilin Province(Introduction of Doctor and High-Level Talents Project)(CXGC2022RCG008)+1 种基金Jilin Province Science and Technology Development Project(20200403014SF)Agricultural Science and Technology Innovation Project of Jilin Province(CXGC2021ZY036).
文摘Soil salinization is the main factor that threatens the growth and development of plants and limits the increase of yield.It is of great significance to study the key soil environmental factors affecting plant root traits to reveal the adaptation strategies of plants to saline-alkaline-stressed soil environments.In this study,the root biomass,root morphological parameters and root mineral nutrient content of two alfalfa cultivars with different sensitivities to alkaline stress were analyzed with black soil as the control group and the mixed saline-alkaline soil with a ratio of 7:3 between black soil and saline-alkaline soil as the saline-alkaline treatment group.At the same time,the correlation analysis of soil salinity indexes,soil nutrient indexes and the activities of key enzymes involved in soil carbon,nitrogen and phosphorus cycles was carried out.The results showed that compared with the control group,the pH,EC,and urease(URE)of the soil surrounding the roots of two alfalfa cultivars were significantly increased,while soil total nitrogen(TN),total phosphorus(TP),organic carbon(SOC),andα-glucosidase activity(AGC)were significantly decreased under saline-alkaline stress.There was no significant difference in root biomass and root morphological parameters of saline-alkaline tolerant cultivar GN under saline-alkaline stress.The number of root tips(RT),root surface area(RS)and root volume(RV)of AG were reduced by 61.16%,44.54%,and 45.31%,respectively,compared with control group.The ratios of K^(+)/Na^(+),Ca^(2+)/Na^(+)and Mg^(2+)/Na^(+)of GN were significantly higher than those of AG(p<0.05).The root fresh weight(RFW)and dry weight(RDW),root length(RL),RV and RT of alfalfa were positively regulated by soil SOC and TN,but negatively regulated by soil pH,EC,and URE(p<0.01).Root Ca^(2+)/Na+ratio was significantly positively correlated with soil TN,TP and SOC(p<0.01).The absorption of Mg and Ca ions in roots is significantly negatively regulated by soilβ-glucosidase activity(BGC)and acid phosphatase activity(APC)(p<0.05).This study improved knowledge of the relationship between root traits and soil environmental factors and offered a theoretical framework for elucidating how plant roots adapt to saline-alkaline stressed soil environments.
文摘Investigating the role of Big Five personality traits in relation to various health outcomes has been extensively studied. The impact of “Big Five” on physical health is here explored for older Europeans with a focus on examining age groups differences. The study sample included 378,500 respondents derived from the seventh data wave of Survey of Health, Aging and Retirement in Europe (SHARE). The physical health status of older Europeans was estimated by constructing an index considering the combined effect of well-established health indicators such as the number of chronic diseases, mobility limitations, limitations with basic and instrumental activities of daily living, and self-perceived health. This index was used for an overall physical health assessment, for which the higher the score for an individual, the worst health level. Then, through a dichotomization process applied to the retrieved Principal Component Analysis scores, a two-group discrimination (good or bad health status) of SHARE participants was obtained as regards their physical health condition, allowing for further con-structing logistic regression models to assess the predictive significance of “Big Five” and their protective role for physical health. Results showed that neuroti-cism was the most significant predictor of physical health for all age groups un-der consideration, while extraversion, agreeableness and openness were not found to significantly affect the self-reported physical health levels of midlife adults aged 50 up to 64. Older adults aged 65 up to 79 were more prone to open-ness, whereas the oldest old individuals aged 80 up to 105 were mainly affected by openness and conscientiousness. .
文摘A central goal of genetics is to understand the links between genetic variation and disease.Intuitively,one might expect diseasecausing variants to cluster into key pathways that drive disease etiology.But for complex traits,association signals tend to be spread across most of the genome-including near many genes without an obvious connection to disease.
基金supported by the National Natural Science Foundation of China(U1804233)the Innovation Scientists and Technicians Troop Construction Projects of Henan Province(202101510003)the Outstanding Youth Fund of the Natural Science Foundation of Henan Province(202300410119).
文摘Tree peony is a unique traditional f lower in China,with large,fragrant,and colorful f lowers.However,a relatively short and concentrated f lowering period limits the applications and production of tree peony.A genome-wide association study(GWAS)was conducted to accelerate molecular breeding for the improvement of f lowering phenology traits and ornamental phenotypes in tree peony.A diverse panel of 451 tree peony accessions was phenotyped for 23 f lowering phenology traits and 4 f loral agronomic traits over 3 years.Genotyping by sequencing(GBS)was used to obtain a large number of genome-wide single-nucleotide polymorphisms(SNPs)(107050)for the panel genotypes,and 1047 candidate genes were identified by association mapping.Eighty-two related genes were observed during at least 2 years for f lowering,and seven SNPs repeatedly identified for multiple f lowering phenology traits over multiple years were highly significantly associated with five genes known to regulate f lowering time.We validated the temporal expression profiles of these candidate genes and highlighted their possible roles in the regulation of f lower bud differentiation and f lowering time in tree peony.This study shows that GWAS based on GBS can be used to identify the genetic determinants of complex traits in tree peony.The results expand our understanding of f lowering time control in perennial woody plants.Identification of markers closely related to these f lowering phenology traits can be used in tree peony breeding programs for important agronomic traits.
基金This work was supported by the National Key Research&Development Program of China(2018YFD1000705/2018YFD1000700)the Natural Science Foundation of Jiangsu Province of China(BK20221213)the China Agriculture Research System(CARS-10-GW01).
文摘Sweetpotato is an important crop that exhibits hexaploidy and high heterozygosity,which limits gene mining for important agronomic traits.Here,314 sweetpotato germplasm resources were deeply resequenced,and 4599509 SNPs and 846654 InDels were generated,among which 196124 SNPs were nonsynonymous and 9690 InDels were frameshifted.Based on the Indels,genome-wide marker primers were designed,and 3219 of 40366 primer pairs were selected to construct the core InDel marker set.The molecular ID of 104 sweetpotato samples verified the availability of these primers.The sweetpotato population structures were then assessed through multiple approaches using SNPs,and diverse approaches demonstrated that population stratification was not obvious for most Chinese germplasm resources.As many as 20 important agronomic traits were evaluated,and a genome-wide association study was conducted on these traits.A total of 19 high-confidence loci were detected in both models.These loci included several candidate genes,such as IbMYB1,IbZEP1,and IbYABBY1,which might be involved in anthocyanin metabolism,carotenoid metabolism,and leaf morphogenesis,respectively.Among them,IbZEP1 and IbYABBY1 were first reported in sweetpotato.The variants in the promoter and the expression levels of IbZEP1 were significantly correlated with f lesh color(orange or not orange)in sweetpotato.The expression levels of IbYABBY1 were also correlated with leaf shape.These results will assist in genetic and breeding studies in sweetpotato.
基金supported by the National Natural Science Foundation of China(Nos.41621061,31500511)the Natural Science Foundation of Shandong Province of China(No.ZR2015CL044)
文摘To clarify the changes in plant photosynthesis and mechanisms underlying those responses to gradually increasing soil drought stress and reveal quantitative relationships between photosynthesis and soil moisture,soil water conditions were controlled in greenhouse pot experiments using 2-year-old seedlings of Forsythia suspensa(Thunb.) Vahl. Photosynthetic gas exchange and chlorophyll fluorescence variables were measured and analyzed under 13 gradients of soil water content. Net photosynthetic rate(PN), stomatal conductance(gs), and water-use efficiency(WUE) in the seedlings exhibited a clear threshold response to the relative soil water content(RSWC). The highest PNand WUEoccurred at RSWCof51.84 and 64.10%, respectively. Both PNand WUEwere higher than the average levels at 39.79% B RSWCB 73.04%. When RSWCdecreased from 51.84 to 37.52%,PN, gs, and the intercellular CO2 concentration(Ci)markedly decreased with increasing drought stress; the corresponding stomatal limitation(Ls) substantially increased, and nonphotochemical quenching(NPQ) also tended to increase, indicating that within this range of soil water content, excessive excitation energy was dispersed from photosystem II(PSII) in the form of heat, and the reduction in PNwas primarily due to stomatal limitation.While RSWCdecreased below 37.52%, there were significant decreases in the maximal quantum yield of PSII photochemistry(Fv/Fm) and the effective quantum yield of PSII photochemistry(UPSII), photochemical quenching(qP), and NPQ; in contrast, minimal fluorescence yield of the dark-adapted state(F0) increased markedly. Thus,the major limiting factor for the PNreduction changed to a nonstomatal limitation due to PSII damage. Therefore, an RSWCof 37.52% is the maximum allowable water deficit for the normal growth of seedlings of F. suspensa, and a water content lower than this level should be avoided in field soil water management. Water contents should be maintained in the range of 39.79% B RSWCB 73.04% to ensure normal function of the photosynthetic apparatus and high levels of photosynthesis and efficiency in F.suspensa.
基金supported by the Ministry of Education,Science and Technological Development of the Republic of Serbia,Grant No.451–03–68/2022–124/200032.
文摘Salinity is one of the major abiotic factors that limit the growth and productivity of plants.Foliar application of plant growth regulators(PGRs)may help plants ameliorate the negative impacts of salinity.Thus,a field experiment was conducted at the Botanical Garden University of Balochistan,Quetta,to explore the potential role of PGRs,i.e.,moringa leaf extract(MLE;10%),proline(PRO;1μM),salicylic acid(SA;250μM),and thiourea(TU;10 mM)in ameliorating the impacts of salinity(120 mM)on Plantago ovata,an important medicinal plant.Salinity hampered plant photosynthetic pigments and metabolites but elevated oxidative parameters.However,foliar application of PGRs enhanced photosynthetic pigments,including Chl b(21.11%),carotenoids(57.87%)except Chl a,activated the defense mechanisms by restoring and enhancing the metabolites,i.e.,soluble sugars(49.68%),soluble phenolics(33.34%),and proline(31.47%),significantly under salinity stress.Furthermore,foliar supplementation of PGRs under salt stress led to a decrease of about 43.02%and 43.27%in hydrogen peroxide and malondialdehyde content,respectively.Thus,PGRs can be recommended for improved photosynthetic efficiency and metabolite content that can help to get better yield under salt stress,with the best and most effective treatments being those of PRO and MLE to predominately ameliorate the harsh impacts of salinity.
基金supported by the Guangzhou Landscaping Company(Grant No.2018–69).
文摘Ceiba species have high ornamental value and are widely cultivated in tropical regions.However,genetic background of cultivated Ceiba plants remains unclear.To understand the genetic relatedness of cultivated Ceiba plants and genetic basis of key horticultural traits,here we explored the genetic relatedness of 153 accessions of Ceiba plants cultivated in Southern China and identified SNPs associated with five horticultural traits,based on 11704 SNPs derived from double-digest restriction-site associated DNA sequencing(ddRAD-seq).Clustering analysis revealed that these accessions were composed of three groups:C.speciosa group,C.insignis group,and hybrid group.The GWAS identified two,four,two,three,and four SNPs related to petal color,petal striation number,flowering time,trunk shape,and prickles on the trunk and branches,respectively.One to two candidate genes were found near the SNPs strongly associated with these traits.This study revealed the genetic relatedness in the Ceiba plants cultivated in Southern China and presented the first GWAS analysis for five horticultural traits for them,laying a foundation for phenotype-related marker selection and molecular breeding.
