Lodging in maize leads to yield losses worldwide.In this study,we determined the effects of traditional and optimized nitrogen management strategies on culm morphological characteristics,culm mechanical strength,ligni...Lodging in maize leads to yield losses worldwide.In this study,we determined the effects of traditional and optimized nitrogen management strategies on culm morphological characteristics,culm mechanical strength,lignin content,root growth,lodging percentage and production in maize at a high plant density.We compared a traditional nitrogen(N)application rate of 300 kg ha–1(R)and an optimized N application rate of 225 kg ha^(–1)(O)under four N application modes:50%of N applied at sowing and 50%at the 10th-leaf stage(N1);100%of N applied at sowing(N2);40%of N applied at sowing,40%at the 10th-leaf stage and 20%at tasseling stage(N3);and 30%of N applied at sowing,30%at the 10th-leaf stage,20%at the tasseling stage,and 20%at the silking stage(N4).The optimized N rate(225 kg ha^(–1))significantly reduced internode lengths,plant height,ear height,center of gravity height and lodging percentage.The optimized N rate significantly increased internode diameters,filling degrees,culm mechanical strength,root growth and lignin content.The application of N in four split doses(N4)significantly improved culm morphological characteristics,culm mechanical strength,lignin content,and root growth,while it reduced internode lengths,plant height,ear height,center of gravity height and lodging percentage.Internode diameters,filling degrees,culm mechanical strength,lignin content,number and diameter of brace roots,root volume,root dry weight,bleeding safe and grain yield were significantly negatively correlated with plant height,ear height,center of gravity height,internode lengths and lodging percentage.In conclusion,treatment ON4 significantly reduced the lodging percentage by improving the culm morphological characteristics,culm mechanical strength,lignin content,and root growth,so it improved the production of the maize crop at a high plant density.展开更多
Grassland degradation can alter the structure and function of ecosystem and soil seed bank.Therefore,estimating the role of soil seed bank in vegetation regeneration of degraded grasslands is crucial.We selected grass...Grassland degradation can alter the structure and function of ecosystem and soil seed bank.Therefore,estimating the role of soil seed bank in vegetation regeneration of degraded grasslands is crucial.We selected grasslands with three levels of degradation,namely non-degraded(ND),mildly degraded(MD),and heavily degraded(HD)to analyze the effect of grassland degradation on soil seed bank,as well as the role of soil seed bank on vegetation regeneration of the alpine grasslands,China.Soil samples from each level were collected in May,before seedling emergence,in August,after completion of transient seed bank germination,and in December,after seed dispersal,to determine the seed density and species composition through germination experiment.Result showed that a total of 35 plant species was identified,including 15 species observed in both soil seed bank and above-ground vegetation.A total of 19,15,and 14 species of soil seed bank were identified in December,May,and August,respectively.The most abundant species in soil seed bank were Compositae(5 species),followed by Poaceae(4 species),and Cyperaceae(3 species).Degradation level has no significant impact on species richness and Shannon-Wiener index of soil seed bank.In addition,sampling month and grassland degradation affected soil seed bank density,in which December>May>August,and ND>MD>HD,indicating that density of transient seed bank was greater than persistent seed bank.Soil seed bank density of surface layer(0–5 cm)accounting for 42%–72%of the total density,which was significantly higher than that of deep layer(5–10 cm).Similarity of species composition between vegetation and soil seed bank was low,and it increased with degradation level(ranged from 0.14 to 0.69).We concluded that grassland degradation affects soil seed bank density more than species diversity,and soil seed bank contributed slightly to vegetation regeneration of degraded alpine grassland.Therefore,it is unlikely that degraded alpine meadow can be restored solely through soil seed bank.展开更多
The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and diversification.Much can be learned about this process from phylo...The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and diversification.Much can be learned about this process from phylogeny-based trait evolution.However,such inference is often plagued by genome-wide gene-tree discordance(GTD),mostly due to incomplete lineage sorting(ILS)and/or introgressive hybridization,especially when the genes underlying the traits appear discordant.Here,by collecting transcriptomes,whole chloroplast genomes(cpDNA),and population genetic datasets,we used the coalescent model to turn GTD into a source of information for ILS and employed hemiplasy to explain specific cases of apparent“phylogenetic discordance”between different morphological traits and probable species phylogeny in the Allium subg.Cyathophora.Both concatenation and coalescence methods consistently showed the same phylogenetic topology for species tree inference based on single-copy genes(SCGs),as supported by the KS distribution.However,GTD was high across the genomes of subg.Cyathophora:~27%e38.9%of the SCG trees were in conflict with the species tree.Plasmid and nuclear incongruence was also present.Our coalescent simulations indicated that such GTD was mainly a product of ILS.Our hemiplasy risk factor calculations supported that random fixation of ancient polymorphisms in different populations during successive speciation events along the subg.Cyathophora phylogeny may have caused the character transition,as well as the anomalous cpDNA tree.Our study exemplifies how phylogenetic noise can be transformed into evolutionary information for understanding character state transitions along species phylogenies.展开更多
Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.Howeve...Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.However,a limited understanding remains of how formal credit affects herders'household expenses.Based on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive expenses.The results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal credit.Formal credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth levels.Moreover,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household expenses.Finally,this study suggests that policies should improve herders'accessibility to formal credit.展开更多
The identification and understanding of cryptic intraspecific evolutionary units(lineages) are crucial for planning effective conservation strategies aimed at preserving genetic diversity in endangered species.However...The identification and understanding of cryptic intraspecific evolutionary units(lineages) are crucial for planning effective conservation strategies aimed at preserving genetic diversity in endangered species.However, the factors driving the evolution and maintenance of these intraspecific lineages in most endangered species remain poorly understood. In this study, we conducted resequencing of 77 individuals from 22 natural populations of Davidia involucrata, a “living fossil” dove tree endemic to central and southwest China. Our analysis revealed the presence of three distinct local lineages within this endangered species, which emerged approximately 3.09 and 0.32 million years ago. These divergence events align well with the geographic and climatic oscillations that occurred across the distributional range.Additionally, we observed frequent hybridization events between the three lineages, resulting in the formation of hybrid populations in their adjacent as well as disjunct regions. These hybridizations likely arose from climate-driven population expansion and/or long-distance gene flow. Furthermore, we identified numerous environment-correlated gene variants across the total and many other genes that exhibited signals of positive evolution during the maintenance of two major local lineages. Our findings shed light on the highly dynamic evolution underlying the remarkably similar phenotype of this endangered species. Importantly, these results not only provide guidance for the development of conservation plans but also enhance our understanding of evolutionary past for this and other endangered species with similar histories.展开更多
In a greenhouse experiment,the effects of soil microorganisms and extracts of Achnatherum inebrians on the seed germination and seedling growth of Elymus nutans were studied.The results showed that both the extracts f...In a greenhouse experiment,the effects of soil microorganisms and extracts of Achnatherum inebrians on the seed germination and seedling growth of Elymus nutans were studied.The results showed that both the extracts from aboveground and belowground parts of A.inebrians significantly inhibited the germination rate,germination potential,germination index,vigor index,seedling height,root length,and fresh weight of E.nutans,but increased malondialdehyde content,catalase,peroxidase and superoxide dismutase activity of E.nutans seedlings(p<0.05).The allelopathy of aqueous extracts of the aboveground parts of A.inebrians was stronger than that of the pre-cipitates.Aqueous extracts of the aboveground parts of A.inebrians decreased seed germination rate,germination potential,germination index,vigor index,seedling length,root length,and seedling fresh weight by 10.45%-74.63%,24.18%-32.50%,19.03%-73.36%,37.83%-88.41%,21.42%-53.14%,2.65%-40.21%,and 20.45%-61.36%,respectively,and malondialdehyde content,peroxidase,catalase,and superoxide dismutase activity increased by 8.09%-62.24%,27.83%-86.47%,22.90%-93.17%,and 11.15%-75.91%,respectively.The above indexes were higher in live soil than in sterilized soil.Soil microorganisms increased the allelopathy of A.inebrians.The seed germination rate,germination potential,germination index,vigor index,seedling length,and seedling fresh weight of E.nutans planted in live soil decreased by 8.22%-48.48%,10.00%-51.85%,8.19%-53.26%,16.43%-60.03%,12.91%-28.81%,and 9.09%-22.86%compared with sterilized soil,respectively.Malondialdehyde content,peroxidase,catalase,and superoxide dismutase activity of E.nutans planted in live soil increased by 53.91%-81.06%,15.71%-57.34%,33.33%-86.31%,and 9.78%-52.51%compared with sterilized soil,respectively.The existence of soil microorganisms enhanced the allelopathy of the secondary metabolites of A.inebrians.A combination of microorganisms and aqueous extracts from the aboveground parts of A.inebrians had the strongest allelopathic effect on E.nutans.展开更多
Background Ferulic acid esterase(FAE)-secreting Lactiplantibacillus plantarum A1(Lp A1)is a promising silage inoculant due to the FAE’s ability to alter the plant cell wall structure during ensiling,an action that is...Background Ferulic acid esterase(FAE)-secreting Lactiplantibacillus plantarum A1(Lp A1)is a promising silage inoculant due to the FAE’s ability to alter the plant cell wall structure during ensiling,an action that is expected to improve forage digestibility.However,little is known regarding the impacts of Lp A1 on rumen microbiota.Our research assessed the influences of Lp A1 in comparison to a widely adopted commercial inoculant Lp MTD/1 on alfalfa’s ensilage,in vitro rumen incubation and microbiota.Results Samples of fresh and ensiled alfalfa treated with(either Lp A1 or Lp MTD/1)or without additives(as control;CON)and ensiled for 30,60 and 90 d were used for fermentation quality,in vitro digestibility and batch culture study.Inoculants treated silage had lower(P<0.001)pH,acetic acid concentration and dry matter(DM)loss,but higher(P=0.001)lactic acid concentration than the CON during ensiling.Compared to the CON and Lp MTD/1,silage treated with Lp A1 had lower(P<0.001)aNDF,ADF,ADL,hemicellulose,and cellulose contents and higher(P<0.001)free ferulic acid concentration.Compared silage treated with Lp MTD/1,silage treated with Lp A1 had significantly(P<0.01)improved ruminal gas production and digestibility,which were equivalent to those of fresh alfalfa.Realtime PCR analysis indicated that Lp A1 inoculation improved the relative abundances of rumen’s total bacteria,fungi,Ruminococcus albus and Ruminococcus flavefaciens,while the relative abundance of methanogens was reduced by Lp MTD/1 compared with CON.Principal component analysis of rumen bacterial 16S rRNA gene amplicons showed a clear distinction between CON and inoculated treatments without noticeable distinction between Lp A1 and Lp MTD/1 treatments.Comparison analysis revealed differences in the relative abundance of some bacteria in different taxa between Lp A1 and Lp MTD/1 treatments.Silage treated with Lp A1 exhibited improved rumen fermentation characteristics due to the inoculant effects on the rumen microbial populations and bacterial community.Conclusions Our findings suggest that silage inoculation of the FAE-producing Lp A1 could be effective in improving silage quality and digestibility,and modulating the rumen fermentation to improve feed utilization.展开更多
Drought and heat stresses cause yield losses in alfalfa,a forage crop cultivated worldwide.Improving its drought and heat tolerance is desirable for maintaining alfalfa productivity in hot,arid regions.Cuticular wax f...Drought and heat stresses cause yield losses in alfalfa,a forage crop cultivated worldwide.Improving its drought and heat tolerance is desirable for maintaining alfalfa productivity in hot,arid regions.Cuticular wax forms a protective barrier on aerial surfaces of land plants against environmental stresses.ABCG11encodes an ATP binding cassette(ABC) transporter that functions in the cuticular wax transport pathway.In this study,Zx ABCG11 from the xerophyte Zygophyllum xanthoxylum was introduced into alfalfa by Agrobacterium tumefaciens-mediated transformation.Compared to the wild type(WT),transgenic alfalfa displayed faster growth,higher wax crystal density,and thicker cuticle on leaves under normal condition.Under either drought or heat treatment in greenhouse conditions,the plant height and shoot biomass of transgenic lines were significantly higher than those of the WT.Transgenic alfalfa showed excellent growth and 50% greater hay yield than WT under field conditions in a hot,arid region.Overexpression of Zx ABCG11 up-regulated wax-related genes and resulted in more cuticular wax deposition,which contributed to reduction of cuticle permeability and thus increased water retention and photosynthesis capacity of transgenic alfalfa.Thus,overexpression of Zx ABCG11 can simultaneously improve biomass yield,drought and heat tolerance in alfalfa by increasing cuticular wax deposition.Our study provides a promising avenue for developing novel forage cultivars suitable for planting in hot,arid,marginal lands.展开更多
The plant natural product scopolin,a coumarin secondary metabolite,has been extensively exploited in flavor,cosmetic,medicine,and other industrial fields.Melilotus albus,a leguminous rotation crop,contains high concen...The plant natural product scopolin,a coumarin secondary metabolite,has been extensively exploited in flavor,cosmetic,medicine,and other industrial fields.Melilotus albus,a leguminous rotation crop,contains high concentrations of coumarin.The transcriptional regulatory network that controls the flow through the scopolin biosynthesis pipeline in M.albus remains poorly understood.MabHLH11 encodes a basic helix–loop–helix(bHLH)transcription factor whose transcription is positively associated with scopolin accumulation and with the expression of MaMYB4,the bHLH partner of the MYB-bHLH complex.Phylogenetic analysis grouped MabHLH11 in the TRANSPARENT TESTA 8(TT8)clade of the bHLH IIIf subgroup.The MabHLH11 protein contained an MYB-interacting region and physically interacted with MaMYB4 in yeast and tobacco leaves.Co-overexpression of MabHLH11 with MaMYB4 in M.albus additively increased the expression of UDP-glucosyltransferase(MaUGT79)and induced more scopolin accumulation than occurred under the expression of MabHLH11 alone.MabHLH11 directly targeted the promoter of MaUGT79 and the activation of MabHLH11 was strengthened by the presence of MaMYB4.Thus,MaMYB4 enhanced the function of MabHLH11 in upregulating scopolin biosynthesis in M.albus,providing a theoretical basis for scalable production of a high-value plant natural product.展开更多
Accurate estimation of crop evapotranspiration(ETc) and soil water balance, which is vital for optimizing water management strategy in crop production, can be performed by simulation. But existing software has many de...Accurate estimation of crop evapotranspiration(ETc) and soil water balance, which is vital for optimizing water management strategy in crop production, can be performed by simulation. But existing software has many deficiencies, including complex operation, limited scalability, lack of batch processing, and a single ETc model. Here we present simET, an open-source software package written in the R programming language. Many concepts involved in crop ETc simulation are condensed into functions in the package. It includes three widely used crop ETc models built on these functions: the single-crop coefficient,double-crop coefficient, and Shuttleworth–Wallace models, along with tools for preparing model data and comparing estimates. SimET supports ETc simulation in crops with repeated growth cycles such as alfalfa, a perennial forage crop that is cut multiple times annually.展开更多
Climate change has become one of the most critical threats to global biodiversity.However,whether phylogenetically related species respond to climate change in similar ways remains controversial.The answer to this que...Climate change has become one of the most critical threats to global biodiversity.However,whether phylogenetically related species respond to climate change in similar ways remains controversial.The answer to this question is crucial for understanding the impacts of climate change and the conservation on the tree of life.By integrating species distribution models with a molecular phylogeny of 50 threatened plant species from one of the global biodiversity hotspots,Gongga Mountains(Mt.Gongga)in southwest China,we evaluated the responses of threatened plant species to future climate change,and estimated whether species responses are phylogenetically conserved.Phylogenetic reconstruction was used to calculate the phylogenetic distance and null model to verify the reliability of the results.We found that correlations between responses of different species to future climate change decreased with the increase in their phylogenetic distance in the monocotyledonous or herbaceous species,but not in the dicotyledonous and woody species.Our results suggested that the responses of herbaceous and monocotyledonous threatened species in Mt.Gongga to future climate change tend to be phylogenetically conserved,while the responses of woody and dicotyledonous threatened species are not.Our study provides evidence for the existence of phylogenetically non-random extinction in the monocotyledonous herbs in Mt.Gongga and highlights the importance of integrating phylogenetic information and evolutionary history into conservation planning.We also provide theoretical basis and technical support for designing effective conservation schemes for the protection of biodiversity under anthropogenic climate change.展开更多
Spatial patterns of plant species and patchy community are important properties in grasslands.However,research regarding spatial patterns of formed patches with various species has not fully advanced until now.Our pur...Spatial patterns of plant species and patchy community are important properties in grasslands.However,research regarding spatial patterns of formed patches with various species has not fully advanced until now.Our purpose is to clarify differences in spatial pattern formed by species and community constructed under shady and terrace habitats.The three common Kobresia-Carex patches(Size 1,0.6–0.9 m^(2);Size 2,3.0–3.8 m^(2) and Size 3,6.5–8.8 m^(2))were selected in shady and terrace on the Qinghai-Tibetan Plateau,and corresponding quadrats of 1m1m,2m2m and 3m3m were placed for S1,S2 and S3 patches,respectively.The surveyed quadrats were divided into 20cm20cm large cells(L-cells),and further divided into four 10cm10cm small cells(S-cells).We used the binary occurrence system(presence/absence data)to record occurrences of all species in S-cells.The analysis shows that the power law model was well able to determine the spatial distribution pattern of species or patchy community in shady and terrace.All species and patches show aggregated distribution in shady and terrace habitats.In the shady habitat,the relative spatial heterogeneity(ε)of individual plant species was lowest at presence frequency(P)of 0.1–0.3,whereas in the terrace habitatεwas lowest at P<0.1,andεincreased monotonically with increasing P.For most dominant species,P andεvalues were higher in terrace than those in shady.We concluded that the dominant species largely determine spatial heterogeneity of the Kobresia-Carex patches,while companion and rare species have weak influence on the community-level heterogeneity in shady and terrace habitats.展开更多
Globally,grassland degradation is an acute ecological problem.In alpine grassland on the Tibetan Plateau,increased densities of various small mammals in degraded grassland are assumed to intensify the degradation proc...Globally,grassland degradation is an acute ecological problem.In alpine grassland on the Tibetan Plateau,increased densities of various small mammals in degraded grassland are assumed to intensify the degradation process and these mammals are subject to lethal control.However,whether the negative impact of small mammals is solely a result of population size or also a result of activity and behavior has not been tested.In this study,we use plateau pika as a model to compare population size,core area of colony,and the number of burrow entrances and latrines between lightly and severely degraded grassland.We test whether the alleged contribution of pika to grassland degradation is a result of increased population size or increased burrowing activities of individuals in response to lower food abundance.We found that grassland degradation resulted in lower plant species richness,plant height,and biomass.Furthermore,the overall population size of pika was not significantly affected by location in lightly and severely degraded grassland.However,pika core areas in severely grassland degradation were significantly larger and had significantly higher densities of burrows and latrines.Our study provides convincing evidence that habitat-induced changes in the behavior of small,burrowing mammals,such as pika,can exacerbate grassland degradation.This finding has significant implications for managing small mammals and restoring degraded grassland ecosystems.展开更多
Bioengineering of photorespiratory bypasses is an effective strategy for improving plant productivity by modulating photosynthesis.In previouswork,two photorespiratory bypasses,theGOC andGCGT bypasses,increased photos...Bioengineering of photorespiratory bypasses is an effective strategy for improving plant productivity by modulating photosynthesis.In previouswork,two photorespiratory bypasses,theGOC andGCGT bypasses,increased photosynthetic rates but decreased seed-setting rate in rice(Oryza sativa),probably owing to excess photosynthate accumulation in the stem.To solve this bottleneck,we successfully developed a newsynthetic photorespiratory bypass(called theGMAbypass)in rice chloroplasts by introducing Oryza sativa glycolate oxidase 1(OsGLO1),Cucurbita maxima malate synthase(CmMS),and Oryza sativa ascorbate peroxidase7(OsAPX7)into the rice genome using a high-efficiency transgene stacking system.Unlike the GOC and GCGT bypass genes driven by constitutive promoters,OsGLO1 in GMA plants was driven by a light-inducible Rubisco small subunit promoter(pRbcS);its expression dynamically changed in response to light,producing a more moderate increase in photosynthate.Photosynthetic rates were significantly increased inGMA plants,and grain yieldswere significantly improved under greenhouse and field conditions.Transgenic GMA rice showed no reduction in seed-setting rate under either test condition,unlike previous photorespiratory-bypass rice,probably reflecting proper modulation of the photorespiratory bypass.Together,these results imply that appropriate engineering of the GMA bypass can enhance rice growth and grain yield without affecting seed-setting rate.展开更多
Wood is an invaluable asset to human society due to its renewable nature,making it suitable for both sustainable energy production and material manufacturing.Additionally,wood derived from forest trees plays a crucial...Wood is an invaluable asset to human society due to its renewable nature,making it suitable for both sustainable energy production and material manufacturing.Additionally,wood derived from forest trees plays a crucial role in sequestering a significant portion of the carbon dioxide fixed during photosynthesis by terrestrial plants.Nevertheless,with the expansion of the global population and ongoing industrialization,forest coverage has been substantially decreased,resulting in significant challenges for wood production and supply.Wood production practices have changed away from natural forests toward plantation forests.Thus,understanding the underlying genetic mechanisms of wood formation is the foundation for developing high-quality,fast-growing plantation trees.Breeding ideal forest trees for wood production using genetic technologies has attracted the interest of many.Tremendous studies have been carried out in recent years on the molecular,genetic,and cell-biological mechanisms of wood formation,and considerable progress and findings have been achieved.These studies and findings indicate enormous possibilities and prospects for tree improvement.This review will outline and assess the cellular and molecular mechanisms of wood formation,as well as studies on genetically improving forest trees,and address future development prospects.展开更多
Hydrological changes under climate warming drive the biogeomorphic succession of wetlands and may trigger substantial carbon loss from the carbon-rich ecosystems.Although many studies have explored the responses of we...Hydrological changes under climate warming drive the biogeomorphic succession of wetlands and may trigger substantial carbon loss from the carbon-rich ecosystems.Although many studies have explored the responses of wetland carbon emissions to short-term hydrological change,it remains poorly understood how the carbon cycle evolves with hydrology-driven wetland succession.Here,we used a space-for-time approach across hydrological gradients on the Tibetan Plateau to examine the dynamics of ecosystem carbon fluxes(carbon dioxide(CO_(2))and methane(CH4))and soil organic carbon pools during alpine wetland succession.We found that the succession from mesic meadow to fen changed the seasonality of both CO_(2) and CH4 fluxes,which was related to the shift in plant community composition,enhanced regulation of soil hydrology and increasing contribution of spring-thaw emission.The paludification caused a switch from net uptake of gaseous carbon to net release on an annual timescale but produced a large accumulation of soil organic carbon.We attempted to attribute the paradox between evidence from the carbon fluxes and pools to the lateral carbon input and the systematic changes of historical climate,given that the wetlands are spatially low-lying with strong temporal climate-carbon cycle interactions.These findings demonstrate a systematic change in the carbon cycle with succession and suggest that biogeomorphic succession and lateral carbon flows are both important for understanding the long-term dynamics of wetland carbon footprints.展开更多
The harsh environment in the Tibetan plateau,the highest place in the world,poses thermoregulatory challenges and hypoxic stress to animals.The impacts of plateau environment on animal physiology and reproduction incl...The harsh environment in the Tibetan plateau,the highest place in the world,poses thermoregulatory challenges and hypoxic stress to animals.The impacts of plateau environment on animal physiology and reproduction include external factors such as strong ultraviolet radiation and low temperature,and internal factors such as animal metabolites and gut microbiota.However,it remains unclear how plateau pika adapt to high altitudes through the combination of serum metabolites and gut microbiota.To this end,we captured 24 wild plateau pikas at the altitudes of 3400,3600,or 3800 m a.s.l.in a Tibetan alpine grassland.Using the machine learning algorithms(random forest),we identified five biomarkers of serum metabolites indicative of the altitudes,that is,dihydrotestosterone,homo-l-arginine,alpha-ketoglutaric-acid,serotonin,and threonine,which were related to body weight,reproduction,and energy metabolism of pika.Those metabolic biomarkers were positively correlated with Lachnospiraceae_Agathobacter,Ruminococcaceae,or Prevotellaceae_Prevotella,suggesting the close relationship between metabolites and gut microbiota.By identifying the metabolic biomarkers and gut microbiota analysis,we reveal the mechanisms of adaptation to high altitudes in plateau pika.展开更多
Background:Epichloësinensis is a newly found endophyte species that is frequently involved in symbiosis with Festuca sinensis.There are a little reports on the characteristics of E.sinensis in vitro.Methods:In th...Background:Epichloësinensis is a newly found endophyte species that is frequently involved in symbiosis with Festuca sinensis.There are a little reports on the characteristics of E.sinensis in vitro.Methods:In the present study,five E.sinensis endophyte strains(strain ID 1,2,41D,57D,111D)isolated from different F.sinensis ecotypes were used to evaluate their antioxidant capacities and enzyme activities.Also,the growth of E.sinensis on potato dextrose agar(PDA)with different additives was investigated.Results:The five strains had significantly different(p<0.05)total antioxidant capacities and radical-scavenging abilities.In most cases,the growth rate of strain 1 was the fastest(p<0.05),and that of strain 57D was the slowest(p<0.05).The growth rates of these five strains on PDA with vitamins significantly(p<0.05)increased with increasing vitamin concentration.The growth rates of these five strains on PDA with plant growth regulators also significantly(p<0.05)increased;however,the increase was inconsistent at different concentrations of indole-3-acetic acid and gibberellin.Low concentrations(5 and 10 mg L−1)of forchlorfenuron(KT-30)significantly promoted the growth of all five strains,whereas high concentrations(20 and 40 mg L−1)of KT-30 significantly inhibited their growth(p<0.05).The Na+,Cd2+,Zn2+,and Cr6+ions all inhibited the growth of these five strains,and their growth rates were significantly decreased with an increase in ion concentrations(p<0.05).Under Na+stress,strain 41D grew the fastest and had the strongest tolerance(p<0.05);under Cd2+,Zn2+,and Cr6+stresses,strain 111D grew the fastest and had the strongest tolerance(p<0.05).Conclusions:The results indicated that the E.sinensis had antioxidant activities and hydrolase activities.Additives could promote or inhibit the growth of the strains in different degrees.All these evaluations in the present study improve our understanding of the E.sinensis endophyte and provide referenced information for further studies.展开更多
The clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)system is a fast-growing,genome editing technology that has wide applications in identifying gene functions as wel...The clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)system is a fast-growing,genome editing technology that has wide applications in identifying gene functions as well as improving agricultural production and crop breeding.Here,we summarized recent advances in the development and applications of genome editing technologies in plants.We briefly described CRISPR/Cas9 technology and examined the base and prime editing techniques that have been developed from CRISPR technology.Some new prime editing-derived techniques were assessed.展开更多
基金supported by projects funded by the China Postdoctoral Science Foundation(2019M663837 and 2021M701521)the National High-Tech Research and Development Programs of China(2013AA102902)the special fund for Agro-scientific Research in the Public Interest,China(201303104)。
文摘Lodging in maize leads to yield losses worldwide.In this study,we determined the effects of traditional and optimized nitrogen management strategies on culm morphological characteristics,culm mechanical strength,lignin content,root growth,lodging percentage and production in maize at a high plant density.We compared a traditional nitrogen(N)application rate of 300 kg ha–1(R)and an optimized N application rate of 225 kg ha^(–1)(O)under four N application modes:50%of N applied at sowing and 50%at the 10th-leaf stage(N1);100%of N applied at sowing(N2);40%of N applied at sowing,40%at the 10th-leaf stage and 20%at tasseling stage(N3);and 30%of N applied at sowing,30%at the 10th-leaf stage,20%at the tasseling stage,and 20%at the silking stage(N4).The optimized N rate(225 kg ha^(–1))significantly reduced internode lengths,plant height,ear height,center of gravity height and lodging percentage.The optimized N rate significantly increased internode diameters,filling degrees,culm mechanical strength,root growth and lignin content.The application of N in four split doses(N4)significantly improved culm morphological characteristics,culm mechanical strength,lignin content,and root growth,while it reduced internode lengths,plant height,ear height,center of gravity height and lodging percentage.Internode diameters,filling degrees,culm mechanical strength,lignin content,number and diameter of brace roots,root volume,root dry weight,bleeding safe and grain yield were significantly negatively correlated with plant height,ear height,center of gravity height,internode lengths and lodging percentage.In conclusion,treatment ON4 significantly reduced the lodging percentage by improving the culm morphological characteristics,culm mechanical strength,lignin content,and root growth,so it improved the production of the maize crop at a high plant density.
基金supported by the National Natural Science Foundation of China (31960279)the Science and Technology Program of Gansu Province, China (21JR11RA018)+1 种基金the Special Project for Central Universities to Build World-class Universities/Disciplines, and Characteristic Development GuidanceProgram for Changjiang Scholars and Innovative Research Team in University of Ministry of Education, China (IRT_17R88)
文摘Grassland degradation can alter the structure and function of ecosystem and soil seed bank.Therefore,estimating the role of soil seed bank in vegetation regeneration of degraded grasslands is crucial.We selected grasslands with three levels of degradation,namely non-degraded(ND),mildly degraded(MD),and heavily degraded(HD)to analyze the effect of grassland degradation on soil seed bank,as well as the role of soil seed bank on vegetation regeneration of the alpine grasslands,China.Soil samples from each level were collected in May,before seedling emergence,in August,after completion of transient seed bank germination,and in December,after seed dispersal,to determine the seed density and species composition through germination experiment.Result showed that a total of 35 plant species was identified,including 15 species observed in both soil seed bank and above-ground vegetation.A total of 19,15,and 14 species of soil seed bank were identified in December,May,and August,respectively.The most abundant species in soil seed bank were Compositae(5 species),followed by Poaceae(4 species),and Cyperaceae(3 species).Degradation level has no significant impact on species richness and Shannon-Wiener index of soil seed bank.In addition,sampling month and grassland degradation affected soil seed bank density,in which December>May>August,and ND>MD>HD,indicating that density of transient seed bank was greater than persistent seed bank.Soil seed bank density of surface layer(0–5 cm)accounting for 42%–72%of the total density,which was significantly higher than that of deep layer(5–10 cm).Similarity of species composition between vegetation and soil seed bank was low,and it increased with degradation level(ranged from 0.14 to 0.69).We concluded that grassland degradation affects soil seed bank density more than species diversity,and soil seed bank contributed slightly to vegetation regeneration of degraded alpine grassland.Therefore,it is unlikely that degraded alpine meadow can be restored solely through soil seed bank.
基金supported by the Key Science & Technology Project of Gansu Province (22ZD6NA007)the National Key Research and Development Program of China (2021YFD2200202)Computing support was provided by the Supercomputing Center of Lanzhou University
文摘The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and diversification.Much can be learned about this process from phylogeny-based trait evolution.However,such inference is often plagued by genome-wide gene-tree discordance(GTD),mostly due to incomplete lineage sorting(ILS)and/or introgressive hybridization,especially when the genes underlying the traits appear discordant.Here,by collecting transcriptomes,whole chloroplast genomes(cpDNA),and population genetic datasets,we used the coalescent model to turn GTD into a source of information for ILS and employed hemiplasy to explain specific cases of apparent“phylogenetic discordance”between different morphological traits and probable species phylogeny in the Allium subg.Cyathophora.Both concatenation and coalescence methods consistently showed the same phylogenetic topology for species tree inference based on single-copy genes(SCGs),as supported by the KS distribution.However,GTD was high across the genomes of subg.Cyathophora:~27%e38.9%of the SCG trees were in conflict with the species tree.Plasmid and nuclear incongruence was also present.Our coalescent simulations indicated that such GTD was mainly a product of ILS.Our hemiplasy risk factor calculations supported that random fixation of ancient polymorphisms in different populations during successive speciation events along the subg.Cyathophora phylogeny may have caused the character transition,as well as the anomalous cpDNA tree.Our study exemplifies how phylogenetic noise can be transformed into evolutionary information for understanding character state transitions along species phylogenies.
基金funding from the National Natural Science Foundation of China (72303086)the Leading Scientist Project of Qinghai Province, China (2023-NK-147)+1 种基金the Consulting Project of Chinese Academy of Engineering (2023-XY-28,2022-XY-139)the Fundamental Research Funds for the Central Universities, China (lzujbky-2022-sp13)
文摘Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.However,a limited understanding remains of how formal credit affects herders'household expenses.Based on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive expenses.The results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal credit.Formal credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth levels.Moreover,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household expenses.Finally,this study suggests that policies should improve herders'accessibility to formal credit.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research program (No. 2019QZKK0502)Strategic Priority Research Program of Chinese Academy of Sciences (No. XDB31010300)+1 种基金Fundamental Research Funds for the Central UniversitiesInternational Collaboration 111 Program (BP0719040)。
文摘The identification and understanding of cryptic intraspecific evolutionary units(lineages) are crucial for planning effective conservation strategies aimed at preserving genetic diversity in endangered species.However, the factors driving the evolution and maintenance of these intraspecific lineages in most endangered species remain poorly understood. In this study, we conducted resequencing of 77 individuals from 22 natural populations of Davidia involucrata, a “living fossil” dove tree endemic to central and southwest China. Our analysis revealed the presence of three distinct local lineages within this endangered species, which emerged approximately 3.09 and 0.32 million years ago. These divergence events align well with the geographic and climatic oscillations that occurred across the distributional range.Additionally, we observed frequent hybridization events between the three lineages, resulting in the formation of hybrid populations in their adjacent as well as disjunct regions. These hybridizations likely arose from climate-driven population expansion and/or long-distance gene flow. Furthermore, we identified numerous environment-correlated gene variants across the total and many other genes that exhibited signals of positive evolution during the maintenance of two major local lineages. Our findings shed light on the highly dynamic evolution underlying the remarkably similar phenotype of this endangered species. Importantly, these results not only provide guidance for the development of conservation plans but also enhance our understanding of evolutionary past for this and other endangered species with similar histories.
基金This work was supported by the Budgetary Project the Chinese Academy of Sciences Leads the Sub-Project of Class A Project(XDA26020202)the National“973”Program Project Topics(2014CB138702)+2 种基金the Basic Scientific Research Business Expenses of Central Universities(Lzujbky-2022-kb10)the 111 Wisdom Base(B12002)the Fundamental Research Funds for the Central Public Welfare Research Institutes(Chinese Academy of Forestry)(CAFYBB2021ZD001).
文摘In a greenhouse experiment,the effects of soil microorganisms and extracts of Achnatherum inebrians on the seed germination and seedling growth of Elymus nutans were studied.The results showed that both the extracts from aboveground and belowground parts of A.inebrians significantly inhibited the germination rate,germination potential,germination index,vigor index,seedling height,root length,and fresh weight of E.nutans,but increased malondialdehyde content,catalase,peroxidase and superoxide dismutase activity of E.nutans seedlings(p<0.05).The allelopathy of aqueous extracts of the aboveground parts of A.inebrians was stronger than that of the pre-cipitates.Aqueous extracts of the aboveground parts of A.inebrians decreased seed germination rate,germination potential,germination index,vigor index,seedling length,root length,and seedling fresh weight by 10.45%-74.63%,24.18%-32.50%,19.03%-73.36%,37.83%-88.41%,21.42%-53.14%,2.65%-40.21%,and 20.45%-61.36%,respectively,and malondialdehyde content,peroxidase,catalase,and superoxide dismutase activity increased by 8.09%-62.24%,27.83%-86.47%,22.90%-93.17%,and 11.15%-75.91%,respectively.The above indexes were higher in live soil than in sterilized soil.Soil microorganisms increased the allelopathy of A.inebrians.The seed germination rate,germination potential,germination index,vigor index,seedling length,and seedling fresh weight of E.nutans planted in live soil decreased by 8.22%-48.48%,10.00%-51.85%,8.19%-53.26%,16.43%-60.03%,12.91%-28.81%,and 9.09%-22.86%compared with sterilized soil,respectively.Malondialdehyde content,peroxidase,catalase,and superoxide dismutase activity of E.nutans planted in live soil increased by 53.91%-81.06%,15.71%-57.34%,33.33%-86.31%,and 9.78%-52.51%compared with sterilized soil,respectively.The existence of soil microorganisms enhanced the allelopathy of the secondary metabolites of A.inebrians.A combination of microorganisms and aqueous extracts from the aboveground parts of A.inebrians had the strongest allelopathic effect on E.nutans.
基金funded by National Natural Science Foundation of China(project no.31901390)China Postdoctoral Science Foundation(project no.2022M711451)Natural Science Foundation of Gansu Province,China(22JR5RA527)。
文摘Background Ferulic acid esterase(FAE)-secreting Lactiplantibacillus plantarum A1(Lp A1)is a promising silage inoculant due to the FAE’s ability to alter the plant cell wall structure during ensiling,an action that is expected to improve forage digestibility.However,little is known regarding the impacts of Lp A1 on rumen microbiota.Our research assessed the influences of Lp A1 in comparison to a widely adopted commercial inoculant Lp MTD/1 on alfalfa’s ensilage,in vitro rumen incubation and microbiota.Results Samples of fresh and ensiled alfalfa treated with(either Lp A1 or Lp MTD/1)or without additives(as control;CON)and ensiled for 30,60 and 90 d were used for fermentation quality,in vitro digestibility and batch culture study.Inoculants treated silage had lower(P<0.001)pH,acetic acid concentration and dry matter(DM)loss,but higher(P=0.001)lactic acid concentration than the CON during ensiling.Compared to the CON and Lp MTD/1,silage treated with Lp A1 had lower(P<0.001)aNDF,ADF,ADL,hemicellulose,and cellulose contents and higher(P<0.001)free ferulic acid concentration.Compared silage treated with Lp MTD/1,silage treated with Lp A1 had significantly(P<0.01)improved ruminal gas production and digestibility,which were equivalent to those of fresh alfalfa.Realtime PCR analysis indicated that Lp A1 inoculation improved the relative abundances of rumen’s total bacteria,fungi,Ruminococcus albus and Ruminococcus flavefaciens,while the relative abundance of methanogens was reduced by Lp MTD/1 compared with CON.Principal component analysis of rumen bacterial 16S rRNA gene amplicons showed a clear distinction between CON and inoculated treatments without noticeable distinction between Lp A1 and Lp MTD/1 treatments.Comparison analysis revealed differences in the relative abundance of some bacteria in different taxa between Lp A1 and Lp MTD/1 treatments.Silage treated with Lp A1 exhibited improved rumen fermentation characteristics due to the inoculant effects on the rumen microbial populations and bacterial community.Conclusions Our findings suggest that silage inoculation of the FAE-producing Lp A1 could be effective in improving silage quality and digestibility,and modulating the rumen fermentation to improve feed utilization.
基金supported by the National Key Research and Development Program of China (2022YFF1003200)the National Natural Science Foundation of China (31730093)。
文摘Drought and heat stresses cause yield losses in alfalfa,a forage crop cultivated worldwide.Improving its drought and heat tolerance is desirable for maintaining alfalfa productivity in hot,arid regions.Cuticular wax forms a protective barrier on aerial surfaces of land plants against environmental stresses.ABCG11encodes an ATP binding cassette(ABC) transporter that functions in the cuticular wax transport pathway.In this study,Zx ABCG11 from the xerophyte Zygophyllum xanthoxylum was introduced into alfalfa by Agrobacterium tumefaciens-mediated transformation.Compared to the wild type(WT),transgenic alfalfa displayed faster growth,higher wax crystal density,and thicker cuticle on leaves under normal condition.Under either drought or heat treatment in greenhouse conditions,the plant height and shoot biomass of transgenic lines were significantly higher than those of the WT.Transgenic alfalfa showed excellent growth and 50% greater hay yield than WT under field conditions in a hot,arid region.Overexpression of Zx ABCG11 up-regulated wax-related genes and resulted in more cuticular wax deposition,which contributed to reduction of cuticle permeability and thus increased water retention and photosynthesis capacity of transgenic alfalfa.Thus,overexpression of Zx ABCG11 can simultaneously improve biomass yield,drought and heat tolerance in alfalfa by increasing cuticular wax deposition.Our study provides a promising avenue for developing novel forage cultivars suitable for planting in hot,arid,marginal lands.
基金the National Natural Science Foundation of China(32061143035,32271752)Inner Mongolia Seed Industry Science and Technology Innovation Major Demonstration Project(2022JBGS0040)the Fundamental Research Funds for the Central Universities(lzujbky-2022-ey17).
文摘The plant natural product scopolin,a coumarin secondary metabolite,has been extensively exploited in flavor,cosmetic,medicine,and other industrial fields.Melilotus albus,a leguminous rotation crop,contains high concentrations of coumarin.The transcriptional regulatory network that controls the flow through the scopolin biosynthesis pipeline in M.albus remains poorly understood.MabHLH11 encodes a basic helix–loop–helix(bHLH)transcription factor whose transcription is positively associated with scopolin accumulation and with the expression of MaMYB4,the bHLH partner of the MYB-bHLH complex.Phylogenetic analysis grouped MabHLH11 in the TRANSPARENT TESTA 8(TT8)clade of the bHLH IIIf subgroup.The MabHLH11 protein contained an MYB-interacting region and physically interacted with MaMYB4 in yeast and tobacco leaves.Co-overexpression of MabHLH11 with MaMYB4 in M.albus additively increased the expression of UDP-glucosyltransferase(MaUGT79)and induced more scopolin accumulation than occurred under the expression of MabHLH11 alone.MabHLH11 directly targeted the promoter of MaUGT79 and the activation of MabHLH11 was strengthened by the presence of MaMYB4.Thus,MaMYB4 enhanced the function of MabHLH11 in upregulating scopolin biosynthesis in M.albus,providing a theoretical basis for scalable production of a high-value plant natural product.
基金jointly supported by the National Natural Science Foundation of China (32171679 and 32201475)。
文摘Accurate estimation of crop evapotranspiration(ETc) and soil water balance, which is vital for optimizing water management strategy in crop production, can be performed by simulation. But existing software has many deficiencies, including complex operation, limited scalability, lack of batch processing, and a single ETc model. Here we present simET, an open-source software package written in the R programming language. Many concepts involved in crop ETc simulation are condensed into functions in the package. It includes three widely used crop ETc models built on these functions: the single-crop coefficient,double-crop coefficient, and Shuttleworth–Wallace models, along with tools for preparing model data and comparing estimates. SimET supports ETc simulation in crops with repeated growth cycles such as alfalfa, a perennial forage crop that is cut multiple times annually.
基金supported by the National Key Research Development Program of China(#2022YFF0802300)the Jiangxi Provincial Natural Science Foundation(20224BAB213033,20232BAB205023)+2 种基金Jiangxi Provincial Department of Education Science and Technology Research Project(GJJ2200433)the National Natural Science Foundation of China(31988102,32125026,32301463)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31000000)。
文摘Climate change has become one of the most critical threats to global biodiversity.However,whether phylogenetically related species respond to climate change in similar ways remains controversial.The answer to this question is crucial for understanding the impacts of climate change and the conservation on the tree of life.By integrating species distribution models with a molecular phylogeny of 50 threatened plant species from one of the global biodiversity hotspots,Gongga Mountains(Mt.Gongga)in southwest China,we evaluated the responses of threatened plant species to future climate change,and estimated whether species responses are phylogenetically conserved.Phylogenetic reconstruction was used to calculate the phylogenetic distance and null model to verify the reliability of the results.We found that correlations between responses of different species to future climate change decreased with the increase in their phylogenetic distance in the monocotyledonous or herbaceous species,but not in the dicotyledonous and woody species.Our results suggested that the responses of herbaceous and monocotyledonous threatened species in Mt.Gongga to future climate change tend to be phylogenetically conserved,while the responses of woody and dicotyledonous threatened species are not.Our study provides evidence for the existence of phylogenetically non-random extinction in the monocotyledonous herbs in Mt.Gongga and highlights the importance of integrating phylogenetic information and evolutionary history into conservation planning.We also provide theoretical basis and technical support for designing effective conservation schemes for the protection of biodiversity under anthropogenic climate change.
基金funded by The Second Tibetan Plateau Scientific Expedition and Research (STEP)program (Grant No.2019QZKK0305)Youth Science and Technology Fund Program of GanSu (Grant No.22JR5RA083)the National Natural Science Foundation of China (Grant No.31971466).
文摘Spatial patterns of plant species and patchy community are important properties in grasslands.However,research regarding spatial patterns of formed patches with various species has not fully advanced until now.Our purpose is to clarify differences in spatial pattern formed by species and community constructed under shady and terrace habitats.The three common Kobresia-Carex patches(Size 1,0.6–0.9 m^(2);Size 2,3.0–3.8 m^(2) and Size 3,6.5–8.8 m^(2))were selected in shady and terrace on the Qinghai-Tibetan Plateau,and corresponding quadrats of 1m1m,2m2m and 3m3m were placed for S1,S2 and S3 patches,respectively.The surveyed quadrats were divided into 20cm20cm large cells(L-cells),and further divided into four 10cm10cm small cells(S-cells).We used the binary occurrence system(presence/absence data)to record occurrences of all species in S-cells.The analysis shows that the power law model was well able to determine the spatial distribution pattern of species or patchy community in shady and terrace.All species and patches show aggregated distribution in shady and terrace habitats.In the shady habitat,the relative spatial heterogeneity(ε)of individual plant species was lowest at presence frequency(P)of 0.1–0.3,whereas in the terrace habitatεwas lowest at P<0.1,andεincreased monotonically with increasing P.For most dominant species,P andεvalues were higher in terrace than those in shady.We concluded that the dominant species largely determine spatial heterogeneity of the Kobresia-Carex patches,while companion and rare species have weak influence on the community-level heterogeneity in shady and terrace habitats.
基金supported by the National Natural Science Foundation of China(Grant No.32192461).
文摘Globally,grassland degradation is an acute ecological problem.In alpine grassland on the Tibetan Plateau,increased densities of various small mammals in degraded grassland are assumed to intensify the degradation process and these mammals are subject to lethal control.However,whether the negative impact of small mammals is solely a result of population size or also a result of activity and behavior has not been tested.In this study,we use plateau pika as a model to compare population size,core area of colony,and the number of burrow entrances and latrines between lightly and severely degraded grassland.We test whether the alleged contribution of pika to grassland degradation is a result of increased population size or increased burrowing activities of individuals in response to lower food abundance.We found that grassland degradation resulted in lower plant species richness,plant height,and biomass.Furthermore,the overall population size of pika was not significantly affected by location in lightly and severely degraded grassland.However,pika core areas in severely grassland degradation were significantly larger and had significantly higher densities of burrows and latrines.Our study provides convincing evidence that habitat-induced changes in the behavior of small,burrowing mammals,such as pika,can exacerbate grassland degradation.This finding has significant implications for managing small mammals and restoring degraded grassland ecosystems.
基金supported by the National Natural Science Foundation of China(3110019,32271757)the Natural Science Foundation of Henan Province(21010338)the Gansu Provincial Science and Technology Major Projects(22ZD6NA007).
文摘Bioengineering of photorespiratory bypasses is an effective strategy for improving plant productivity by modulating photosynthesis.In previouswork,two photorespiratory bypasses,theGOC andGCGT bypasses,increased photosynthetic rates but decreased seed-setting rate in rice(Oryza sativa),probably owing to excess photosynthate accumulation in the stem.To solve this bottleneck,we successfully developed a newsynthetic photorespiratory bypass(called theGMAbypass)in rice chloroplasts by introducing Oryza sativa glycolate oxidase 1(OsGLO1),Cucurbita maxima malate synthase(CmMS),and Oryza sativa ascorbate peroxidase7(OsAPX7)into the rice genome using a high-efficiency transgene stacking system.Unlike the GOC and GCGT bypass genes driven by constitutive promoters,OsGLO1 in GMA plants was driven by a light-inducible Rubisco small subunit promoter(pRbcS);its expression dynamically changed in response to light,producing a more moderate increase in photosynthate.Photosynthetic rates were significantly increased inGMA plants,and grain yieldswere significantly improved under greenhouse and field conditions.Transgenic GMA rice showed no reduction in seed-setting rate under either test condition,unlike previous photorespiratory-bypass rice,probably reflecting proper modulation of the photorespiratory bypass.Together,these results imply that appropriate engineering of the GMA bypass can enhance rice growth and grain yield without affecting seed-setting rate.
基金supported by the National Natural Science Foundation of China(Grant No.32271827 to Y.Z.and Grant No.32130072 to L.L.)Excellent Youth Foundation of Gansu Scientific Committee(Grant No.22JR5RA394)to Y.Z.the National Key Research and Development Program(2021YFD2200204)to L.L。
文摘Wood is an invaluable asset to human society due to its renewable nature,making it suitable for both sustainable energy production and material manufacturing.Additionally,wood derived from forest trees plays a crucial role in sequestering a significant portion of the carbon dioxide fixed during photosynthesis by terrestrial plants.Nevertheless,with the expansion of the global population and ongoing industrialization,forest coverage has been substantially decreased,resulting in significant challenges for wood production and supply.Wood production practices have changed away from natural forests toward plantation forests.Thus,understanding the underlying genetic mechanisms of wood formation is the foundation for developing high-quality,fast-growing plantation trees.Breeding ideal forest trees for wood production using genetic technologies has attracted the interest of many.Tremendous studies have been carried out in recent years on the molecular,genetic,and cell-biological mechanisms of wood formation,and considerable progress and findings have been achieved.These studies and findings indicate enormous possibilities and prospects for tree improvement.This review will outline and assess the cellular and molecular mechanisms of wood formation,as well as studies on genetically improving forest trees,and address future development prospects.
基金supported by the National Natural Science Foundation of China (32130065,31901145,32111530062)the Discipline Construction Fund of Peking University and the Academy of Finland (341294).
文摘Hydrological changes under climate warming drive the biogeomorphic succession of wetlands and may trigger substantial carbon loss from the carbon-rich ecosystems.Although many studies have explored the responses of wetland carbon emissions to short-term hydrological change,it remains poorly understood how the carbon cycle evolves with hydrology-driven wetland succession.Here,we used a space-for-time approach across hydrological gradients on the Tibetan Plateau to examine the dynamics of ecosystem carbon fluxes(carbon dioxide(CO_(2))and methane(CH4))and soil organic carbon pools during alpine wetland succession.We found that the succession from mesic meadow to fen changed the seasonality of both CO_(2) and CH4 fluxes,which was related to the shift in plant community composition,enhanced regulation of soil hydrology and increasing contribution of spring-thaw emission.The paludification caused a switch from net uptake of gaseous carbon to net release on an annual timescale but produced a large accumulation of soil organic carbon.We attempted to attribute the paradox between evidence from the carbon fluxes and pools to the lateral carbon input and the systematic changes of historical climate,given that the wetlands are spatially low-lying with strong temporal climate-carbon cycle interactions.These findings demonstrate a systematic change in the carbon cycle with succession and suggest that biogeomorphic succession and lateral carbon flows are both important for understanding the long-term dynamics of wetland carbon footprints.
基金The authors are very grateful for the valuable comments on manuscript revisions of the editor.The authors are grateful to Metware Biotechnology Co.,Ltd for their contribution and assistance in Targeted 500 metabolomics analysis.This study was financially supported by the Leading Scientist Project of Qinghai Province(2023-NK-147)the Foundation of Science and Technology of Gansu Province(22JR5RA457)+4 种基金the Fundamental Research Funds for the Central Universities(lzujbky-2022-ct04)the National Natural Science Foundation of China(32061123004)the Open Fund Project of Guangxi Key Laboratory of Precision Medicine for Genetic Diseases(GXWCH-ZDKF-2022-15,Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region)the Open Fund Project of Guangxi Key Laboratory of Reproductive Health and Birth Defect Prevention(GXWCH-ZDKF-2022-09,Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region)the Foundation of Guangxi Health Commission(S2021068).
文摘The harsh environment in the Tibetan plateau,the highest place in the world,poses thermoregulatory challenges and hypoxic stress to animals.The impacts of plateau environment on animal physiology and reproduction include external factors such as strong ultraviolet radiation and low temperature,and internal factors such as animal metabolites and gut microbiota.However,it remains unclear how plateau pika adapt to high altitudes through the combination of serum metabolites and gut microbiota.To this end,we captured 24 wild plateau pikas at the altitudes of 3400,3600,or 3800 m a.s.l.in a Tibetan alpine grassland.Using the machine learning algorithms(random forest),we identified five biomarkers of serum metabolites indicative of the altitudes,that is,dihydrotestosterone,homo-l-arginine,alpha-ketoglutaric-acid,serotonin,and threonine,which were related to body weight,reproduction,and energy metabolism of pika.Those metabolic biomarkers were positively correlated with Lachnospiraceae_Agathobacter,Ruminococcaceae,or Prevotellaceae_Prevotella,suggesting the close relationship between metabolites and gut microbiota.By identifying the metabolic biomarkers and gut microbiota analysis,we reveal the mechanisms of adaptation to high altitudes in plateau pika.
基金National Nature Science Foundation of China(31971768)Gansu Transportation Department Science and Technology Project(2021-07 and 2021-28).
文摘Background:Epichloësinensis is a newly found endophyte species that is frequently involved in symbiosis with Festuca sinensis.There are a little reports on the characteristics of E.sinensis in vitro.Methods:In the present study,five E.sinensis endophyte strains(strain ID 1,2,41D,57D,111D)isolated from different F.sinensis ecotypes were used to evaluate their antioxidant capacities and enzyme activities.Also,the growth of E.sinensis on potato dextrose agar(PDA)with different additives was investigated.Results:The five strains had significantly different(p<0.05)total antioxidant capacities and radical-scavenging abilities.In most cases,the growth rate of strain 1 was the fastest(p<0.05),and that of strain 57D was the slowest(p<0.05).The growth rates of these five strains on PDA with vitamins significantly(p<0.05)increased with increasing vitamin concentration.The growth rates of these five strains on PDA with plant growth regulators also significantly(p<0.05)increased;however,the increase was inconsistent at different concentrations of indole-3-acetic acid and gibberellin.Low concentrations(5 and 10 mg L−1)of forchlorfenuron(KT-30)significantly promoted the growth of all five strains,whereas high concentrations(20 and 40 mg L−1)of KT-30 significantly inhibited their growth(p<0.05).The Na+,Cd2+,Zn2+,and Cr6+ions all inhibited the growth of these five strains,and their growth rates were significantly decreased with an increase in ion concentrations(p<0.05).Under Na+stress,strain 41D grew the fastest and had the strongest tolerance(p<0.05);under Cd2+,Zn2+,and Cr6+stresses,strain 111D grew the fastest and had the strongest tolerance(p<0.05).Conclusions:The results indicated that the E.sinensis had antioxidant activities and hydrolase activities.Additives could promote or inhibit the growth of the strains in different degrees.All these evaluations in the present study improve our understanding of the E.sinensis endophyte and provide referenced information for further studies.
基金National Natural Science Foundation of China(NSFC)(31571464,31371438,and 31070222 to Q.S.Q.)Qinghai Provincial Department of Science and Technology Qinghai basic research program(2022-ZJ-724 to Q.S.Q.)+3 种基金Qinghai Provincial Department of Science and Technology Innovation Platform Construction Fund(2020-ZJ-Y40 to Q.S.Q.)Independent Research and Development Project of State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems(202202 to Q.S.Q.)Special Project in Key Fields of the Ordinary Universities of Guangdong Provincial Department(2021ZDZX4027)Innovation Team Project of Ordinary Universities of Guangdong Province(2021KCXTD011).
文摘The clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)system is a fast-growing,genome editing technology that has wide applications in identifying gene functions as well as improving agricultural production and crop breeding.Here,we summarized recent advances in the development and applications of genome editing technologies in plants.We briefly described CRISPR/Cas9 technology and examined the base and prime editing techniques that have been developed from CRISPR technology.Some new prime editing-derived techniques were assessed.
