1.Introduction Crop breeding is transitioning to engineering by synthetic biology.Conventional breeding,constrained by limited genetic variation and lengthy development cycles,cannot meet the challenges of micronutrie...1.Introduction Crop breeding is transitioning to engineering by synthetic biology.Conventional breeding,constrained by limited genetic variation and lengthy development cycles,cannot meet the challenges of micronutrient malnutrition and yield reductions from climate change with sufficient speed or precision[1].Consequently,agriculture is transitioning from selection-based breeding to designbased engineering.Synthetic biology enables the precision modification of metabolic pathways and the construction of novel trait combinations[1,2].This special issue,Synthetic Biology for Crop Improvement,brings together 26 articles that showcase the field’s transition from laboratory curiosity to field-validated agricultural technology.The collection spans 13 plant species,from staple grains and major industrial crops to horticultural and medicinal plants,demonstrating the universal applicability of metabolic engineering.These studies reveal maturation toward field readiness:independent groups achieving reproducible results in identical pathways,greenhouse concepts advancing to multi-season field trials,and engineered traits delivering measurable agronomic value.This progression answers the central question in crop synthetic biology,shifting the paradigm from asking“can it work?”to demonstrating“how it works,and here are the yields”.This transformation is grounded in understanding and manipulating plant metabolism at molecular resolution[3].展开更多
The plant germplasm resources harboring abundant genetic variations are necessary wealth in developing new cultivars adapted to various geographic and seasonal conditions.Unraveling the complex genetic architecture un...The plant germplasm resources harboring abundant genetic variations are necessary wealth in developing new cultivars adapted to various geographic and seasonal conditions.Unraveling the complex genetic architecture underlying phenotypic diversity in germplasm population is essential in studies on genetics,evolution and breeding plans for crop species.Mapping quantitative trait loci(QTLs)using molecular markers provide a basic tool for understanding the inheritance of quantitative traits,while the genomewide association study(GWAS)is a potential approach to detecting the whole-genome QTLs and their corresponding alleles in a germplasm population.The previous GWAS detects QTLs by taking high-density single-nucleotide polymorphism(SNP)markers to identify genotypephenotype associations,and has been extensively used for genetic dissection of quantitative traits in plants(Huang and Han 2014).展开更多
Starch is an essential commodity for humans and other animals.Future demands require qualitative and quantitative improvement by crop and post-harvest engineering that calls for comprehensive actions requiring increas...Starch is an essential commodity for humans and other animals.Future demands require qualitative and quantitative improvement by crop and post-harvest engineering that calls for comprehensive actions requiring increased fundamental knowledge on starch biosynthesis,development of advanced breeding strategies,efficient farming,and well-adapted and up scalable extraction protocols for diverse starch products.Recent staggering progress in molecular breeding techniques,especially genome editing,have enabled generation of higher starch yield and special functional qualities required to support such advancement.However,this necessitates fundamental biochemical and mechanistic understanding of starch biosynthesis and the variegated starch crop germplasms,all of which are closely linked to the relationships between starch molecular structures and functionality of various starch types as directed by the different capabilities of starch crop genotypes.We here review starch biosynthesis and its genetic foundation with a focus on increasing nutritional and health-promoting value of starch especially through bioengineering of the high amylose trait.展开更多
A predictive model of meiotic crossover engineering would increase precision in crop breeding.We review the biological principles underlying crossover formation and chromosomal distribution,hierarchical control mechan...A predictive model of meiotic crossover engineering would increase precision in crop breeding.We review the biological principles underlying crossover formation and chromosomal distribution,hierarchical control mechanisms enforcing crossover assurance,and an emerging phase-separation model determining crossover interference patterning.展开更多
Drought is a natural disaster that profoundly impacts on global agricultural production,significantly reduces crop yields,and thereby poses a severe threat to worldwide food security.Addressing the challenge of effect...Drought is a natural disaster that profoundly impacts on global agricultural production,significantly reduces crop yields,and thereby poses a severe threat to worldwide food security.Addressing the challenge of effectively improving crop drought resistance(DR)to mitigate yield loss under drought conditions is a global issue.An optimal root system architecture(RSA)plays a pivotal role in enhancing the capacity of crops to efficiently uptake water and nutrients,which consequently strengthens their resilience against environmental stresses.In this review,we discuss the compositions and roles of crop RSA and summarize the most recent developments in augmenting drought tolerance in crops by manipulating RSA-related genes.Based on the current research,we propose the potential optimal RSA configuration that could be helpful in enhancing crop DR.Lastly,we discuss the existing challenges and future directions for breeding crops with enhanced DR capabilities through genetic improvements targeting RSA.展开更多
Staple crops such as rice,wheat,and maize are crucial for global food security;however,improving their quality remains a significant challenge.This review summarizes recent advances in enhancing crop quality,focusing ...Staple crops such as rice,wheat,and maize are crucial for global food security;however,improving their quality remains a significant challenge.This review summarizes recent advances in enhancing crop quality,focusing on key areas such as the molecular mechanisms underlying endosperm filling initiation,starch granule synthesis,protein body formation,and the interactions between carbon and nitrogen metabolism.It also highlights ten unresolved questions related to starch-protein spatial distribution,epigenetic regulation,and the environmental impacts on quality traits.The integration of multi-omics approaches and rational design strategies presents opportunities to develop high-yield“super-crop”varieties with enhanced nutritional value,better processing characteristics,and attributes preferred by consumers.Addressing these challenges is crucial to promote sustainable agriculture and achieve the dual objectives of food security and environmental conservation.展开更多
Qingke,a staple crop grown on the high-altitude Tibetan Plateau,has evolved a metabolomic profile providing both environmental stress resilience and human nutrition.We review the hypothesis that the metabolites that c...Qingke,a staple crop grown on the high-altitude Tibetan Plateau,has evolved a metabolomic profile providing both environmental stress resilience and human nutrition.We review the hypothesis that the metabolites that confer cold and UV resistance on the crop also facilitate human adaptation to high-altitude stresses.Specifically,β-glucans regulate blood glucose primarily via short-chain fatty acids(SCFAs)produced through gut microbiota fermentation,which directly mediate glucose homeostasis.Phenolamides accumulate via the phenylpropanoid pathway,with chalcone isomerase(CHI)serving as a key enzyme in flavonoid biosynthesis and enhancing UV-B resistance.Under low temperatures,β-glucans improve frost tolerance by modulating osmotic balance and inhibiting ice-nucleating proteins,while lipids maintain membrane fluidity to sustain cellular function during cold stress.Importantly,we explore the hypothesis that these same metabolites,upon consumption,may facilitate human adaptation to high-altitude stresses.This hypothesis is supported by preliminary epidemiological associations between Qingke consumption and favorable health outcomes in high-altitude populations,as well as established bioactivities of the implicated metabolites in vitro and in animal models.However,direct causal evidence in humans and a comprehensive understanding of the underlying molecular mechanisms remain key knowledge gaps that warrant future investigation.Qingke as a unique resource at the interface of agricultural resilience and human nutrition.Understanding its metabolic blueprint will inform the development of functional foods and climate-resilient crops.展开更多
Cotton production faces significant challenges from insect pests,with chemical pesticide use becoming increasingly limited by resistance and environmental concerns.This study explores the potential use of caffeine,a n...Cotton production faces significant challenges from insect pests,with chemical pesticide use becoming increasingly limited by resistance and environmental concerns.This study explores the potential use of caffeine,a natural plant alkaloid,as an environmentally friendly insect resistance strategy in cotton.Exogenous caffeine application demonstrated potent insecticidal effects against cotton bollworm(Helicoverpa armigera)larvae,with concentrations≥2 mg mL−1 causing near-complete feeding cessation and up to 70%larval mortality.Building on this,we engineered transgenic cotton(Gossypium hirsutum cv.Jin668)for heterologous caffeine biosynthesis by introducing three key N-methyltransferase genes(CaXMT1,CaMXMT1,CaDXMT1)by multiple gene transformation.Transgenic lines expressing all three genes showed remarkable caffeine accumulation(up to 3.59 mg g−1 dry weight),whereas two-gene combinations exhibited wild-type-level production.Feeding preference assays revealed that caffeine-enriched cotton strongly deterred feeding by H.armigera.Non-choice feeding trials demonstrated reduced leaf consumption and reduced larval growth in H.armigera fed on caffeine-producing cotton.The study highlights the effectiveness of synthetic biology approaches using the TGSII-UNiE multigene stacking system,despite challenges in transgene stability.This work advances plant-derived insect resistance research and provides a sustainable framework for reducing chemical pesticide reliance in cotton production,while underscoring unique potential of cotton as a synthetic biology platform for secondary metabolite engineering.展开更多
Licochalcone A(LCA)is a characteristic compound in licorice Glycyrrhiza inflata and is widely utilized in pharmaceutical and cosmetic industries.However,the biosynthetic pathway and regulatory mechanisms of LCA remain...Licochalcone A(LCA)is a characteristic compound in licorice Glycyrrhiza inflata and is widely utilized in pharmaceutical and cosmetic industries.However,the biosynthetic pathway and regulatory mechanisms of LCA remain poorly understood.In this study,we first found the accumulation of LCA is induced by methyl jasmonate(MeJA).Given that MYB transcriptional factors are well-documented as key regulators of flavonoid biosynthesis,we identified a total of 147 GiR2R3-MYB genes in G.inflata,which were classified into 28 subgroups.The chromosome distributions,sequence characteristics,gene structures,duplication events and cis-acting elements were also investigated.Through integrated analysis of GiR2R3-MYBs expression patterns across different tissues and under MeJA treatment,along with phylogenetic relationship,we identified GiMYB76—a MeJA-inducible MYB transcription factor—as a potential regulator of LCA accumulation.Functional validation showed that transgenic hairy roots overexpressing GiMYB76 exhibited a significant increase in LCA content.DAP-seq analysis of GiMYB76 revealed potential target genes involved in flavonoid biosynthesis regulation.Subsequent promoter activity assay verified that GiMYB76 can bind to the promoter and activate the expression of GiCHS4.Consistently,overexpression of GiCHS4 in G.inflata hairy roots also significantly enhanced LCA production.This study not only clarifies that GiMYB76 transcriptionally activated GiCHS4 to promote LCA biosynthesis but also provides valuable insights for basic research on licorice and the development of related industries.展开更多
Improved yield potential is the goal of barley domestication and cultivation.During this process,two-and six-rowed barley types emerged and have been utilised in breeding and production.The six-rowed type could produc...Improved yield potential is the goal of barley domestication and cultivation.During this process,two-and six-rowed barley types emerged and have been utilised in breeding and production.The six-rowed type could produce three times as many grains as its ancestral two-rowed forms,thus dominating barley cultivation for thousands of years.The deficiens form of the two-rowed type,characterised by extremely suppressed lateral spikelets,has gained dominance over the past few decades in barley-growing regions worldwide.We hypothesised that the absence of lateral spikelets in deficiens barley affects spike architecture and spike-related traits,contributing to its superior yield potential of deficiens barley cultivation.Currently,a deficiens barley variety,RGT Planet,is the most popular barley variety in the world.In this study,we used two F_(2) populations derived from crossing RGT Planet with two canonical two-rowed barley and identified the functional allele Vrs1.t1 associated with deficiens morphology.We observed that the Vrs1.t1 allele may contribute to high yield potential by optimising spike architecture through increased spikelet length,grain number,and grain size.Phylogenetic analysis suggests that the deficiens mutation was likely present from the early stages of barley cultivation in the Fertile Crescent and spread to Ethiopia and beyond with agricultural expansion.We conclude that the ancient deficiens allele Vrs1.t1 has been a critical driver for the recent success of modern barley improvement by optimising spike architecture.展开更多
In recent years,an unusual wilt disease affecting Pyrus pyrifolia has been observed in various regions of Jiangsu,China.This disease originates from the roots and progresses with distinctive browning patterns along va...In recent years,an unusual wilt disease affecting Pyrus pyrifolia has been observed in various regions of Jiangsu,China.This disease originates from the roots and progresses with distinctive browning patterns along vascular tissues,even extending over two meters above the ground.These symptoms set it apart from recognized pear diseases and typically lead to the death of affected trees within the same or the following year.Furthermore,this disease exhibits a tendency to spread to neighboring trees even after the removal of affected trees,presenting a substantial threat to pear production.To ascertain the causative agent,the present study encompassed pathogen isolation,morphological and molecular identification,as well as validation experiments adhering to Koch's postulates.The fungal isolates obtained were identified as Fusarium cugenangense based on characteristics of the colonies and conidia,in addition to a phylogenetic analysis using DNA sequences of the translation elongation factor 1-alpha(tef1),calmodulin(Ca M),and RNA polymerase second largest subunit(rpb2)genes.Pathogenicity of the isolated F.cugenangense on pear was confirmed by artificial inoculation.By introducing GFP-labeled pathogens into the roots,colonization in stem and leaf tissues was observed via fluorescence microscopy and transmission electron microscopy.Furthermore,these pathogens were successfully reisolated from stems and foliage,conclusively providing evidence of systemic infection within the pear plants.To the best of our knowledge,this is the first report of F.cugenangense causing pear wilt disease in China.展开更多
In previous studies, integrative crop management (ICM) improved shoot growth and grain yield of rice (Oryza sativa L.). However, little is known about the effect of ICM on root growth and methane (CH4) emission of pad...In previous studies, integrative crop management (ICM) improved shoot growth and grain yield of rice (Oryza sativa L.). However, little is known about the effect of ICM on root growth and methane (CH4) emission of paddy rice. In this study, two rice varieties, Wuyunjing 24 and Yongyou 2640, were grown. A field experiment was conducted with three crop management treatments including zero nitrogen fertilization (0N), local farmer practice (LFP), and ICM. Root morphophysiological traits and CH4 emission from the paddy field were investigated. ICM significantly increased mean grain yield by 29.9%, with the effect attributed mainly to an increase in mean total number of spikelets by 26.4% compared to LFP. ICM increased root and shoot biomass, root length, number of roots, root oxidation activity (ROA), root bleeding rate, and root total and active absorbing surface area by respectively 24.4%, 25.7%, 17.1%, 9.3%, 18.7%, 29.5%, 12.1%, and 24.7%. The concentrations of malic, succinic, and acetic acids in root exudates were respectively 5.8%, 6.0%, and 10.5% higher in ICM than in LFP. Compared to LFP, ICM significantly decreased the rate of CH4 emission during emission peak stages and reduced total CH4 emission by 17.1%. The root morphophysiological traits were positively and significantly correlated with grain yield, whereas root length, specific root length, ROA, and root total and active absorbing surface area were negatively and significantly correlated with total CH4 emission. These results suggest that ICM could achieve the dual goals of increasing grain yield and reducing the greenhouse gas effect by improving the root morphology and physiological traits of paddy rice.展开更多
Dissecting the genetic architecture of complex traits is an ongoing challenge for geneticists.Two complementary approaches for genetic mapping,linkage mapping and association mapping have led to successful dissection ...Dissecting the genetic architecture of complex traits is an ongoing challenge for geneticists.Two complementary approaches for genetic mapping,linkage mapping and association mapping have led to successful dissection of complex traits in many crop species.Both of these methods detect quantitative trait loci(QTL) by identifying marker–trait associations,and the only fundamental difference between them is that between mapping populations,which directly determine mapping resolution and power.Based on this difference,we first summarize in this review the advances and limitations of family-based mapping and natural population-based mapping instead of linkage mapping and association mapping.We then describe statistical methods used for improving detection power and computational speed and outline emerging areas such as large-scale meta-analysis for genetic mapping in crops.In the era of next-generation sequencing,there has arisen an urgent need for proper population design,advanced statistical strategies,and precision phenotyping to fully exploit high-throughput genotyping.展开更多
With the rapid development of genetic analysis techniques and crop population size,phenotyping has become the bottleneck restricting crop breeding.Breaking through this bottleneck will require phenomics,defined as the...With the rapid development of genetic analysis techniques and crop population size,phenotyping has become the bottleneck restricting crop breeding.Breaking through this bottleneck will require phenomics,defined as the accurate,high-throughput acquisition and analysis of multi-dimensional phenotypes during crop growth at organism-wide levels,ranging from cells to organs,individual plants,plots,and fields.Here we offer an overview of crop phenomics research from technological and platform viewpoints at various scales,including microscopic,ground-based,and aerial phenotyping and phenotypic data analysis.We describe recent applications of high-throughput phenotyping platforms for abiotic/biotic stress and yield assessment.Finally,we discuss current challenges and offer perspectives on future phenomics research.展开更多
Celery(Apium graveolens L.)is a vegetable crop in the Apiaceae family that is widely cultivated and consumed because it contains necessary nutrients and multiple biologically active ingredients,such as apigenin and te...Celery(Apium graveolens L.)is a vegetable crop in the Apiaceae family that is widely cultivated and consumed because it contains necessary nutrients and multiple biologically active ingredients,such as apigenin and terpenoids.Here,we report the genome sequence of celery based on the use of HiSeq 2000 sequencing technology to obtain 600.8 Gb of data,achieving~189-fold genome coverage,from 68 sequencing libraries with different insert sizes ranging from 180 bp to 10 kb in length.The assembled genome has a total sequence length of 2.21 Gb and consists of 34,277 predicted genes.Repetitive DNA sequences represent 68.88%of the genome sequences,and LTR retrotransposons are the main components of the repetitive sequences.Evolutionary analysis showed that a recent whole-genome duplication event may have occurred in celery,which could have contributed to its large genome size.The genome sequence of celery allowed us to identify agronomically important genes involved in disease resistance,flavonoid biosynthesis,terpenoid metabolism,and other important cellular processes.The comparative analysis of apigenin biosynthesis genes among species might explain the high apigenin content of celery.The whole-genome sequences of celery have been deposited at CeleryDB(http://apiaceae.njau.edu.cn/celerydb).The availability of the celery genome data advances our knowledge of the genetic evolution of celery and will contribute to further biological research and breeding in celery as well as other Apiaceae plants.展开更多
Yield loss(Y_(Loss)) in the ratoon crop due to crushing damage to left stubble from mechanical harvesting of the main crop is a constraint for wide adoption of mechanized rice ratooning technology.Soil drying before t...Yield loss(Y_(Loss)) in the ratoon crop due to crushing damage to left stubble from mechanical harvesting of the main crop is a constraint for wide adoption of mechanized rice ratooning technology.Soil drying before the harvest of the main crop has been proposed to overcome this problem.The objective of this study was to determine the effect of soil drying during the mid-to-late grain filling stage of the main crop on grain yield of the ratoon crop in a mechanized rice ratooning system.Field experiments were conducted to compare Y_(Loss) between light(LD) and heavy(HD) soil drying treatments in Hubei province,central China in 2017 and 2018.Y_(Loss) was calculated as the percentage of yield reduction in the ratoon crop with the main crop harvested mechanically,relative to the grain yield of the ratoon crop with the main crop harvested manually.In comparison with LD,soil hardness was increased by 42.8%-84.7% in HD at the 5-20 cm soil depth at maturity of the main crop.Soil hardness at 5 and 10 cm depths reached respectively 4.05 and 7.07 kg cm^(-2) in HD.Soil drying treatment did not significantly affect the grain yield of the main crop.Under mechanical harvesting of the main crop,HD increased the grain yield of the ratoon crop by 9.4% relative to LD.Consequently,Y_(Loss) was only 3.4% in HD,in contrast to 16.3% in LD.The differences in grain yield and Y_(Loos) between the two soil drying treatments were explained mainly by panicles m^(-2),which was increased significantly by HD in the track zone of the ratoon crop compared with LD.These results suggest that heavy soil drying practice during the mid-to-late grain filling stage of the main crop is effective for reducing Y_(Loss) of the ratoon crop in a mechanized rice ratooning system.展开更多
With marker and phenotype information from observed populations, genomic selection （GS） can be used to establish associations between markers and phenotypes. It aims to use genome-wide markers to estimate the effect...With marker and phenotype information from observed populations, genomic selection （GS） can be used to establish associations between markers and phenotypes. It aims to use genome-wide markers to estimate the effects of all loci and thereby predict the genetic values of untested populations, so as to achieve more comprehensive and reliable selection and to accelerate genetic progress in crop breeding. GS models usually face the problem that the number of markers is much higher than the number of phenotypic observations. To overcome this issue and improve prediction accuracy, many models and algorithms, including GBLUP, Bayes, and machine learning have been employed for GS. As hot issues in GS research, the estimation of non-additive genetic effects and the combined analysis of multiple traits or multiple environments are also important for improving the accuracy of prediction. In recent years, crop breeding has taken advantage of the development of GS. The principles and characteristics of current popular GS methods and research progress in hese methods for crop improvement are reviewed in this paper.展开更多
Ratoon rice cropping is an important component of the rice cropping system in Texas and south Louisiana,USA,and expanded to Asian countries in 1970.Two field studies were conducted with widely planted rice(Oryza sativ...Ratoon rice cropping is an important component of the rice cropping system in Texas and south Louisiana,USA,and expanded to Asian countries in 1970.Two field studies were conducted with widely planted rice(Oryza sativa L.)cultivars at Eagle Lake,Texas,USA to determine the effects of nitrogen(N)management in main(first)crop(MC)and ratoon(second)crop(RC)on RC yield.In 2012 and 2013,one cultivar(Presidio)was adopted to determine the effects of RC N management on ratoon yield and head rice yield.In 2016 and 2017,CL153,CL163 and CL272 in addition to Presidio were adopted to examine the effect of MC N management on ratoon yield and head rice yield.N applied at preflood after MC harvest considerably improved RC yield.Application of 99 kg N ha^(–1)at preflood after MC harvest was practically adequate for RC regrowth,development and approaching the yield potential for Presidio.RC could produce quite high average grain yields of 5.90 to 6.53 t ha–1 in 2012 and 2013,respectively.Main crop N rate only significantly affected MC yield;however,given N applied of 99 kg ha^(–1)at preflood after MC harvest,ratoon yield was not significantly affected by MC N rate.Neither the main nor ratoon crop N management had a significant effect on RC head rice yield.Considerable RC head rice yields(55–65%)were observed in all of the four cultivars and 4 years except for CL272 in 2016.These results indicat that without very high N fertilizer application,rice ratoon crop could produce a considerable grain yield and an expectative head rice yield.Rice ratooning could be a practical way to increase rice yields with the minimal input in south Texas and regions with a similar climate.展开更多
Among the potential non-food energy crops,the sugar-rich C4 grass sweet sorghum and the biomass-rich Miscanthus are increasingly considered as two leading candidates.Here,we outline the biological traits of these ener...Among the potential non-food energy crops,the sugar-rich C4 grass sweet sorghum and the biomass-rich Miscanthus are increasingly considered as two leading candidates.Here,we outline the biological traits of these energy crops for largescale production in China.We also review recent progress on understanding of plant cell wall composition and wall polymer features of both plant species from large populations that affect both biomass enzymatic digestibility and ethanol conversion rates under various pretreatment conditions.We finally propose genetic approaches to enhance biomass production,enzymatic digestibility and sugar-ethanol conversion efficiency of the energy crops.展开更多
The growth and yield of peanut are negatively affected by continuous cropping.Arbuscular mycorrhizal fungi(AMF)and calcium ions(Ca^(2+))have been used to improve stress resistance in other plants,but little is known a...The growth and yield of peanut are negatively affected by continuous cropping.Arbuscular mycorrhizal fungi(AMF)and calcium ions(Ca^(2+))have been used to improve stress resistance in other plants,but little is known about their roles in peanut seedling growth under continuous cropping.This study investigated the possible roles of the AMF Glomus mosseae combined with exogenous Ca^(2+)in improving the physiological responses of peanut seedlings under continuous cropping.G.mosseae combined with exogenous Ca^(2+)can enhance plant biomass,Ca^(2+)level,and total chlorophyll content.Under exogenous Ca^(2+)application,the F_v/F_m in arbuscular mycorrhizal(AM)plant leaves was higher than that in the control plants when they were exposed to high irradiance levels.The peroxidase,superoxide dismutase,and catalase activities in AM plant leaves also reached their maximums,and accordingly,the malondialdehyde content was the lowest compared to other treatments.Additionally,root activity,and content of total phenolics and flavonoids were significantly increased in AM plant roots treated by Ca^(2+)compared to either G.mosseae inoculation or Ca^(2+)treatment alone.Transcription levels of AhCaM,AhCDPK,AhRAM1,and AhRAM2 were significantly improved in AM plant roots under exogenous Ca^(2+)treatment.This implied that exogenous Ca^(2+)might be involved in the regulation of G.mosseae colonization of peanut plants,and in turn,AM symbiosis might activate the Ca^(2+)signal transduction pathway.The combination of AMF and Ca^(2+)benefitted plant growth and development under continuous cropping,suggesting that it is a promising method to cope with the stress caused by continuous cropping.展开更多
文摘1.Introduction Crop breeding is transitioning to engineering by synthetic biology.Conventional breeding,constrained by limited genetic variation and lengthy development cycles,cannot meet the challenges of micronutrient malnutrition and yield reductions from climate change with sufficient speed or precision[1].Consequently,agriculture is transitioning from selection-based breeding to designbased engineering.Synthetic biology enables the precision modification of metabolic pathways and the construction of novel trait combinations[1,2].This special issue,Synthetic Biology for Crop Improvement,brings together 26 articles that showcase the field’s transition from laboratory curiosity to field-validated agricultural technology.The collection spans 13 plant species,from staple grains and major industrial crops to horticultural and medicinal plants,demonstrating the universal applicability of metabolic engineering.These studies reveal maturation toward field readiness:independent groups achieving reproducible results in identical pathways,greenhouse concepts advancing to multi-season field trials,and engineered traits delivering measurable agronomic value.This progression answers the central question in crop synthetic biology,shifting the paradigm from asking“can it work?”to demonstrating“how it works,and here are the yields”.This transformation is grounded in understanding and manipulating plant metabolism at molecular resolution[3].
基金supported by the National Natural Science Foundation of China(31701447)the National R&D Program of China(2016YFD0100201,2016YFD0100304,2017YFD0100500,and 2017YFD0102002)+4 种基金the 111 Project of Ministry of Education,China(B08025)the Program for Changjiang Scholars and Innovative Research Team in University,China(PCSIRT_17R55)the earmarked fund for China Agriculture Research System(CARS-04)the Fundamental Research Funds for the Central Universities,China(KYT201801)the Jiangsu Collaborative Innovation Center for Modern Crop Production,China。
文摘The plant germplasm resources harboring abundant genetic variations are necessary wealth in developing new cultivars adapted to various geographic and seasonal conditions.Unraveling the complex genetic architecture underlying phenotypic diversity in germplasm population is essential in studies on genetics,evolution and breeding plans for crop species.Mapping quantitative trait loci(QTLs)using molecular markers provide a basic tool for understanding the inheritance of quantitative traits,while the genomewide association study(GWAS)is a potential approach to detecting the whole-genome QTLs and their corresponding alleles in a germplasm population.The previous GWAS detects QTLs by taking high-density single-nucleotide polymorphism(SNP)markers to identify genotypephenotype associations,and has been extensively used for genetic dissection of quantitative traits in plants(Huang and Han 2014).
文摘Starch is an essential commodity for humans and other animals.Future demands require qualitative and quantitative improvement by crop and post-harvest engineering that calls for comprehensive actions requiring increased fundamental knowledge on starch biosynthesis,development of advanced breeding strategies,efficient farming,and well-adapted and up scalable extraction protocols for diverse starch products.Recent staggering progress in molecular breeding techniques,especially genome editing,have enabled generation of higher starch yield and special functional qualities required to support such advancement.However,this necessitates fundamental biochemical and mechanistic understanding of starch biosynthesis and the variegated starch crop germplasms,all of which are closely linked to the relationships between starch molecular structures and functionality of various starch types as directed by the different capabilities of starch crop genotypes.We here review starch biosynthesis and its genetic foundation with a focus on increasing nutritional and health-promoting value of starch especially through bioengineering of the high amylose trait.
基金funded by the National Natural Science Foundation of China(U2102219 and 32370901)the Project of Zhongshan Biological Breeding Laboratory(ZSBBL-KY2023-06-3).
文摘A predictive model of meiotic crossover engineering would increase precision in crop breeding.We review the biological principles underlying crossover formation and chromosomal distribution,hierarchical control mechanisms enforcing crossover assurance,and an emerging phase-separation model determining crossover interference patterning.
基金supported by the Key Technologies Research and Development Program,China(2022YFE0100500)the National Natural Science Foundation of China(31971954,31960405,32061143031)+2 种基金Hainan Yazhou Bay Seed Lab and China National Seed Group(B23YQ1510)Gansu Province Industrial Support Plan(2022CYZC-46)Postdoctoral Fellowship Program of CPSF(GZC20230909).
文摘Drought is a natural disaster that profoundly impacts on global agricultural production,significantly reduces crop yields,and thereby poses a severe threat to worldwide food security.Addressing the challenge of effectively improving crop drought resistance(DR)to mitigate yield loss under drought conditions is a global issue.An optimal root system architecture(RSA)plays a pivotal role in enhancing the capacity of crops to efficiently uptake water and nutrients,which consequently strengthens their resilience against environmental stresses.In this review,we discuss the compositions and roles of crop RSA and summarize the most recent developments in augmenting drought tolerance in crops by manipulating RSA-related genes.Based on the current research,we propose the potential optimal RSA configuration that could be helpful in enhancing crop DR.Lastly,we discuss the existing challenges and future directions for breeding crops with enhanced DR capabilities through genetic improvements targeting RSA.
基金supported by the National Natural Science Foundation of China(32230074,32125030,32161143004)the Pinduoduo-China Agricultural University Research Fund(PC2023A01003)the Natural Science Foundation of Jiangsu Province(BK20220567).
文摘Staple crops such as rice,wheat,and maize are crucial for global food security;however,improving their quality remains a significant challenge.This review summarizes recent advances in enhancing crop quality,focusing on key areas such as the molecular mechanisms underlying endosperm filling initiation,starch granule synthesis,protein body formation,and the interactions between carbon and nitrogen metabolism.It also highlights ten unresolved questions related to starch-protein spatial distribution,epigenetic regulation,and the environmental impacts on quality traits.The integration of multi-omics approaches and rational design strategies presents opportunities to develop high-yield“super-crop”varieties with enhanced nutritional value,better processing characteristics,and attributes preferred by consumers.Addressing these challenges is crucial to promote sustainable agriculture and achieve the dual objectives of food security and environmental conservation.
基金supported by the Financial Special Fund,grant number XZ202401JD0027National Barley Industry Technology System(CARS-05-01A-08)+3 种基金the Xizang Agri-Tech Innovation Project(XZNKY-2025-CXGC-T01)the Joint Funds of the National Natural Science Foundation of China(No.U20A2026)the Financial Special Fund,grant number(32401784,2017CZZX001/2,XZNKY-2018-C-021 and NYSTC202401)the China Agriculture Research System of Barley(CARS-05).
文摘Qingke,a staple crop grown on the high-altitude Tibetan Plateau,has evolved a metabolomic profile providing both environmental stress resilience and human nutrition.We review the hypothesis that the metabolites that confer cold and UV resistance on the crop also facilitate human adaptation to high-altitude stresses.Specifically,β-glucans regulate blood glucose primarily via short-chain fatty acids(SCFAs)produced through gut microbiota fermentation,which directly mediate glucose homeostasis.Phenolamides accumulate via the phenylpropanoid pathway,with chalcone isomerase(CHI)serving as a key enzyme in flavonoid biosynthesis and enhancing UV-B resistance.Under low temperatures,β-glucans improve frost tolerance by modulating osmotic balance and inhibiting ice-nucleating proteins,while lipids maintain membrane fluidity to sustain cellular function during cold stress.Importantly,we explore the hypothesis that these same metabolites,upon consumption,may facilitate human adaptation to high-altitude stresses.This hypothesis is supported by preliminary epidemiological associations between Qingke consumption and favorable health outcomes in high-altitude populations,as well as established bioactivities of the implicated metabolites in vitro and in animal models.However,direct causal evidence in humans and a comprehensive understanding of the underlying molecular mechanisms remain key knowledge gaps that warrant future investigation.Qingke as a unique resource at the interface of agricultural resilience and human nutrition.Understanding its metabolic blueprint will inform the development of functional foods and climate-resilient crops.
基金supported by the National Natural Science Foundation of China (32325039)
文摘Cotton production faces significant challenges from insect pests,with chemical pesticide use becoming increasingly limited by resistance and environmental concerns.This study explores the potential use of caffeine,a natural plant alkaloid,as an environmentally friendly insect resistance strategy in cotton.Exogenous caffeine application demonstrated potent insecticidal effects against cotton bollworm(Helicoverpa armigera)larvae,with concentrations≥2 mg mL−1 causing near-complete feeding cessation and up to 70%larval mortality.Building on this,we engineered transgenic cotton(Gossypium hirsutum cv.Jin668)for heterologous caffeine biosynthesis by introducing three key N-methyltransferase genes(CaXMT1,CaMXMT1,CaDXMT1)by multiple gene transformation.Transgenic lines expressing all three genes showed remarkable caffeine accumulation(up to 3.59 mg g−1 dry weight),whereas two-gene combinations exhibited wild-type-level production.Feeding preference assays revealed that caffeine-enriched cotton strongly deterred feeding by H.armigera.Non-choice feeding trials demonstrated reduced leaf consumption and reduced larval growth in H.armigera fed on caffeine-producing cotton.The study highlights the effectiveness of synthetic biology approaches using the TGSII-UNiE multigene stacking system,despite challenges in transgene stability.This work advances plant-derived insect resistance research and provides a sustainable framework for reducing chemical pesticide reliance in cotton production,while underscoring unique potential of cotton as a synthetic biology platform for secondary metabolite engineering.
基金supported by the Guangdong Basic and Applied Basic Research Foundation (2025A1515012679)Open Fund of Shanghai Key Laboratory of Plant Functional Genomics and Resources (PFGR202502)
文摘Licochalcone A(LCA)is a characteristic compound in licorice Glycyrrhiza inflata and is widely utilized in pharmaceutical and cosmetic industries.However,the biosynthetic pathway and regulatory mechanisms of LCA remain poorly understood.In this study,we first found the accumulation of LCA is induced by methyl jasmonate(MeJA).Given that MYB transcriptional factors are well-documented as key regulators of flavonoid biosynthesis,we identified a total of 147 GiR2R3-MYB genes in G.inflata,which were classified into 28 subgroups.The chromosome distributions,sequence characteristics,gene structures,duplication events and cis-acting elements were also investigated.Through integrated analysis of GiR2R3-MYBs expression patterns across different tissues and under MeJA treatment,along with phylogenetic relationship,we identified GiMYB76—a MeJA-inducible MYB transcription factor—as a potential regulator of LCA accumulation.Functional validation showed that transgenic hairy roots overexpressing GiMYB76 exhibited a significant increase in LCA content.DAP-seq analysis of GiMYB76 revealed potential target genes involved in flavonoid biosynthesis regulation.Subsequent promoter activity assay verified that GiMYB76 can bind to the promoter and activate the expression of GiCHS4.Consistently,overexpression of GiCHS4 in G.inflata hairy roots also significantly enhanced LCA production.This study not only clarifies that GiMYB76 transcriptionally activated GiCHS4 to promote LCA biosynthesis but also provides valuable insights for basic research on licorice and the development of related industries.
基金Funding for this research was provided by the Australia Grain Research and Development Corporation(9176507)the Western Crop Genetics Alliance.Jingye Cheng thanks The University of Tasmania,Australia for the scholarship(495802)。
文摘Improved yield potential is the goal of barley domestication and cultivation.During this process,two-and six-rowed barley types emerged and have been utilised in breeding and production.The six-rowed type could produce three times as many grains as its ancestral two-rowed forms,thus dominating barley cultivation for thousands of years.The deficiens form of the two-rowed type,characterised by extremely suppressed lateral spikelets,has gained dominance over the past few decades in barley-growing regions worldwide.We hypothesised that the absence of lateral spikelets in deficiens barley affects spike architecture and spike-related traits,contributing to its superior yield potential of deficiens barley cultivation.Currently,a deficiens barley variety,RGT Planet,is the most popular barley variety in the world.In this study,we used two F_(2) populations derived from crossing RGT Planet with two canonical two-rowed barley and identified the functional allele Vrs1.t1 associated with deficiens morphology.We observed that the Vrs1.t1 allele may contribute to high yield potential by optimising spike architecture through increased spikelet length,grain number,and grain size.Phylogenetic analysis suggests that the deficiens mutation was likely present from the early stages of barley cultivation in the Fertile Crescent and spread to Ethiopia and beyond with agricultural expansion.We conclude that the ancient deficiens allele Vrs1.t1 has been a critical driver for the recent success of modern barley improvement by optimising spike architecture.
基金supported by the Jiangsu Agricultural Science and Technology Innovation Fund,China(CX(23)1011)the Earmarked Fund for China Agriculture Research System(CARS-28)+3 种基金the National Natural Science Foundation of China(31901837)the China Postdoctoral Science Foundation(2020M671389)the Basal Research Fund for the Jiangsu Academy of Agricultural Sciences,China(ZX(23)3016)the Yafu Technology Service Project,China(KF(23)1106)。
文摘In recent years,an unusual wilt disease affecting Pyrus pyrifolia has been observed in various regions of Jiangsu,China.This disease originates from the roots and progresses with distinctive browning patterns along vascular tissues,even extending over two meters above the ground.These symptoms set it apart from recognized pear diseases and typically lead to the death of affected trees within the same or the following year.Furthermore,this disease exhibits a tendency to spread to neighboring trees even after the removal of affected trees,presenting a substantial threat to pear production.To ascertain the causative agent,the present study encompassed pathogen isolation,morphological and molecular identification,as well as validation experiments adhering to Koch's postulates.The fungal isolates obtained were identified as Fusarium cugenangense based on characteristics of the colonies and conidia,in addition to a phylogenetic analysis using DNA sequences of the translation elongation factor 1-alpha(tef1),calmodulin(Ca M),and RNA polymerase second largest subunit(rpb2)genes.Pathogenicity of the isolated F.cugenangense on pear was confirmed by artificial inoculation.By introducing GFP-labeled pathogens into the roots,colonization in stem and leaf tissues was observed via fluorescence microscopy and transmission electron microscopy.Furthermore,these pathogens were successfully reisolated from stems and foliage,conclusively providing evidence of systemic infection within the pear plants.To the best of our knowledge,this is the first report of F.cugenangense causing pear wilt disease in China.
基金supported by the National Basic Research Program of China (2015CB150404)the National Key Research and Development Program of China (2016YFD0300206-4, 2018YFD0300801)+4 种基金the National Natural Science Foundation of China (31871559, 31671614)Young Elite Scientists Sponsorship Program by CAST (2016QNRC001)the Natural Science Foundation of the Jiangsu Higher Education Institutions (15KJA210005)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe Top Talent Supporting Program of Yangzhou University (2015-01)
文摘In previous studies, integrative crop management (ICM) improved shoot growth and grain yield of rice (Oryza sativa L.). However, little is known about the effect of ICM on root growth and methane (CH4) emission of paddy rice. In this study, two rice varieties, Wuyunjing 24 and Yongyou 2640, were grown. A field experiment was conducted with three crop management treatments including zero nitrogen fertilization (0N), local farmer practice (LFP), and ICM. Root morphophysiological traits and CH4 emission from the paddy field were investigated. ICM significantly increased mean grain yield by 29.9%, with the effect attributed mainly to an increase in mean total number of spikelets by 26.4% compared to LFP. ICM increased root and shoot biomass, root length, number of roots, root oxidation activity (ROA), root bleeding rate, and root total and active absorbing surface area by respectively 24.4%, 25.7%, 17.1%, 9.3%, 18.7%, 29.5%, 12.1%, and 24.7%. The concentrations of malic, succinic, and acetic acids in root exudates were respectively 5.8%, 6.0%, and 10.5% higher in ICM than in LFP. Compared to LFP, ICM significantly decreased the rate of CH4 emission during emission peak stages and reduced total CH4 emission by 17.1%. The root morphophysiological traits were positively and significantly correlated with grain yield, whereas root length, specific root length, ROA, and root total and active absorbing surface area were negatively and significantly correlated with total CH4 emission. These results suggest that ICM could achieve the dual goals of increasing grain yield and reducing the greenhouse gas effect by improving the root morphology and physiological traits of paddy rice.
基金supported by the Priority Academic Program Development of Jiangsu Higher Education Institutionthe National Natural Science Foundation of China(Nos.91535103,31391632,and 31200943)+4 种基金the National High Technology Research and Development Program of China(No.2014AA10A601-5)the Natural Science Foundation of Jiangsu Province(No.BK2012261)the Natural Science Foundation of Jiangsu Higher Education Institution(No.14KJA210005)the Postgraduate Research and Innovation Project in Jiangsu Province(No.KYLX151368)the Innovative Research Team of University in Jiangsu Province
文摘Dissecting the genetic architecture of complex traits is an ongoing challenge for geneticists.Two complementary approaches for genetic mapping,linkage mapping and association mapping have led to successful dissection of complex traits in many crop species.Both of these methods detect quantitative trait loci(QTL) by identifying marker–trait associations,and the only fundamental difference between them is that between mapping populations,which directly determine mapping resolution and power.Based on this difference,we first summarize in this review the advances and limitations of family-based mapping and natural population-based mapping instead of linkage mapping and association mapping.We then describe statistical methods used for improving detection power and computational speed and outline emerging areas such as large-scale meta-analysis for genetic mapping in crops.In the era of next-generation sequencing,there has arisen an urgent need for proper population design,advanced statistical strategies,and precision phenotyping to fully exploit high-throughput genotyping.
基金supported by the National Key Research and Development Program of China(2016YFD0100101-18,2020YFD1000904-1-3)the National Natural Science Foundation of China(31601216,31770397)Fundamental Research Funds for the Central Universities(2662019QD053,2662020ZKPY017)。
文摘With the rapid development of genetic analysis techniques and crop population size,phenotyping has become the bottleneck restricting crop breeding.Breaking through this bottleneck will require phenomics,defined as the accurate,high-throughput acquisition and analysis of multi-dimensional phenotypes during crop growth at organism-wide levels,ranging from cells to organs,individual plants,plots,and fields.Here we offer an overview of crop phenomics research from technological and platform viewpoints at various scales,including microscopic,ground-based,and aerial phenotyping and phenotypic data analysis.We describe recent applications of high-throughput phenotyping platforms for abiotic/biotic stress and yield assessment.Finally,we discuss current challenges and offer perspectives on future phenomics research.
基金supported by the Jiangsu Agriculture Science and Technology Innovation Fund(CX(18)2007)New Century Excellent Talents in University(NCET-11-0670)National Natural Science Foundation of China。
文摘Celery(Apium graveolens L.)is a vegetable crop in the Apiaceae family that is widely cultivated and consumed because it contains necessary nutrients and multiple biologically active ingredients,such as apigenin and terpenoids.Here,we report the genome sequence of celery based on the use of HiSeq 2000 sequencing technology to obtain 600.8 Gb of data,achieving~189-fold genome coverage,from 68 sequencing libraries with different insert sizes ranging from 180 bp to 10 kb in length.The assembled genome has a total sequence length of 2.21 Gb and consists of 34,277 predicted genes.Repetitive DNA sequences represent 68.88%of the genome sequences,and LTR retrotransposons are the main components of the repetitive sequences.Evolutionary analysis showed that a recent whole-genome duplication event may have occurred in celery,which could have contributed to its large genome size.The genome sequence of celery allowed us to identify agronomically important genes involved in disease resistance,flavonoid biosynthesis,terpenoid metabolism,and other important cellular processes.The comparative analysis of apigenin biosynthesis genes among species might explain the high apigenin content of celery.The whole-genome sequences of celery have been deposited at CeleryDB(http://apiaceae.njau.edu.cn/celerydb).The availability of the celery genome data advances our knowledge of the genetic evolution of celery and will contribute to further biological research and breeding in celery as well as other Apiaceae plants.
基金supported by the Major International (Regional)Joint Research Project of National Natural Science Foundation of China (32061143038)the China Agriculture Research System(CARS-01-20)the Fundamental Research Funds for the Central Universities (2662020ZKPY015)。
文摘Yield loss(Y_(Loss)) in the ratoon crop due to crushing damage to left stubble from mechanical harvesting of the main crop is a constraint for wide adoption of mechanized rice ratooning technology.Soil drying before the harvest of the main crop has been proposed to overcome this problem.The objective of this study was to determine the effect of soil drying during the mid-to-late grain filling stage of the main crop on grain yield of the ratoon crop in a mechanized rice ratooning system.Field experiments were conducted to compare Y_(Loss) between light(LD) and heavy(HD) soil drying treatments in Hubei province,central China in 2017 and 2018.Y_(Loss) was calculated as the percentage of yield reduction in the ratoon crop with the main crop harvested mechanically,relative to the grain yield of the ratoon crop with the main crop harvested manually.In comparison with LD,soil hardness was increased by 42.8%-84.7% in HD at the 5-20 cm soil depth at maturity of the main crop.Soil hardness at 5 and 10 cm depths reached respectively 4.05 and 7.07 kg cm^(-2) in HD.Soil drying treatment did not significantly affect the grain yield of the main crop.Under mechanical harvesting of the main crop,HD increased the grain yield of the ratoon crop by 9.4% relative to LD.Consequently,Y_(Loss) was only 3.4% in HD,in contrast to 16.3% in LD.The differences in grain yield and Y_(Loos) between the two soil drying treatments were explained mainly by panicles m^(-2),which was increased significantly by HD in the track zone of the ratoon crop compared with LD.These results suggest that heavy soil drying practice during the mid-to-late grain filling stage of the main crop is effective for reducing Y_(Loss) of the ratoon crop in a mechanized rice ratooning system.
基金supported by grants from the National High Technology Research and Development Program of China(2014AA10A601-5)the National Key Research and Development Program of China(2016YFD0100303)+5 种基金the National Natural Science Foundation of China(91535103)the Natural Science Foundations of Jiangsu Province(BK20150010)the Natural Science Foundation of the Jiangsu Higher Education Institutions(14KJA210005)the Open Research Fund of State Key Laboratory of Hybrid Rice(Wuhan University)(KF201701)the Science and Technology Innovation Fund Project in Yangzhou University(2016CXJ021)the Priority Academic Program Development of Jiangsu Higher Education Institutions and the Innovative Research Team of Universities in Jiangsu Province
文摘With marker and phenotype information from observed populations, genomic selection （GS） can be used to establish associations between markers and phenotypes. It aims to use genome-wide markers to estimate the effects of all loci and thereby predict the genetic values of untested populations, so as to achieve more comprehensive and reliable selection and to accelerate genetic progress in crop breeding. GS models usually face the problem that the number of markers is much higher than the number of phenotypic observations. To overcome this issue and improve prediction accuracy, many models and algorithms, including GBLUP, Bayes, and machine learning have been employed for GS. As hot issues in GS research, the estimation of non-additive genetic effects and the combined analysis of multiple traits or multiple environments are also important for improving the accuracy of prediction. In recent years, crop breeding has taken advantage of the development of GS. The principles and characteristics of current popular GS methods and research progress in hese methods for crop improvement are reviewed in this paper.
文摘Ratoon rice cropping is an important component of the rice cropping system in Texas and south Louisiana,USA,and expanded to Asian countries in 1970.Two field studies were conducted with widely planted rice(Oryza sativa L.)cultivars at Eagle Lake,Texas,USA to determine the effects of nitrogen(N)management in main(first)crop(MC)and ratoon(second)crop(RC)on RC yield.In 2012 and 2013,one cultivar(Presidio)was adopted to determine the effects of RC N management on ratoon yield and head rice yield.In 2016 and 2017,CL153,CL163 and CL272 in addition to Presidio were adopted to examine the effect of MC N management on ratoon yield and head rice yield.N applied at preflood after MC harvest considerably improved RC yield.Application of 99 kg N ha^(–1)at preflood after MC harvest was practically adequate for RC regrowth,development and approaching the yield potential for Presidio.RC could produce quite high average grain yields of 5.90 to 6.53 t ha–1 in 2012 and 2013,respectively.Main crop N rate only significantly affected MC yield;however,given N applied of 99 kg ha^(–1)at preflood after MC harvest,ratoon yield was not significantly affected by MC N rate.Neither the main nor ratoon crop N management had a significant effect on RC head rice yield.Considerable RC head rice yields(55–65%)were observed in all of the four cultivars and 4 years except for CL272 in 2016.These results indicat that without very high N fertilizer application,rice ratoon crop could produce a considerable grain yield and an expectative head rice yield.Rice ratooning could be a practical way to increase rice yields with the minimal input in south Texas and regions with a similar climate.
基金supported by grants from the Fundamental Research Funds for the Central Universities Project , China (2013QC042)the Fundamental Research Funds for the 111 Project of Ministry of Education of China (B08032)the Starting Foundation for Changjiang Scholars Program of Ministry of Education of China (52204-14004)
文摘Among the potential non-food energy crops,the sugar-rich C4 grass sweet sorghum and the biomass-rich Miscanthus are increasingly considered as two leading candidates.Here,we outline the biological traits of these energy crops for largescale production in China.We also review recent progress on understanding of plant cell wall composition and wall polymer features of both plant species from large populations that affect both biomass enzymatic digestibility and ethanol conversion rates under various pretreatment conditions.We finally propose genetic approaches to enhance biomass production,enzymatic digestibility and sugar-ethanol conversion efficiency of the energy crops.
基金supported by the National Natural Science Foundation of China (31601261, 31601252, 31571581 and 31571605)the China Postdoctoral Science Foundation (2016M592236)
文摘The growth and yield of peanut are negatively affected by continuous cropping.Arbuscular mycorrhizal fungi(AMF)and calcium ions(Ca^(2+))have been used to improve stress resistance in other plants,but little is known about their roles in peanut seedling growth under continuous cropping.This study investigated the possible roles of the AMF Glomus mosseae combined with exogenous Ca^(2+)in improving the physiological responses of peanut seedlings under continuous cropping.G.mosseae combined with exogenous Ca^(2+)can enhance plant biomass,Ca^(2+)level,and total chlorophyll content.Under exogenous Ca^(2+)application,the F_v/F_m in arbuscular mycorrhizal(AM)plant leaves was higher than that in the control plants when they were exposed to high irradiance levels.The peroxidase,superoxide dismutase,and catalase activities in AM plant leaves also reached their maximums,and accordingly,the malondialdehyde content was the lowest compared to other treatments.Additionally,root activity,and content of total phenolics and flavonoids were significantly increased in AM plant roots treated by Ca^(2+)compared to either G.mosseae inoculation or Ca^(2+)treatment alone.Transcription levels of AhCaM,AhCDPK,AhRAM1,and AhRAM2 were significantly improved in AM plant roots under exogenous Ca^(2+)treatment.This implied that exogenous Ca^(2+)might be involved in the regulation of G.mosseae colonization of peanut plants,and in turn,AM symbiosis might activate the Ca^(2+)signal transduction pathway.The combination of AMF and Ca^(2+)benefitted plant growth and development under continuous cropping,suggesting that it is a promising method to cope with the stress caused by continuous cropping.
