Flooding stress is a major adverse condition during the emergence period of direct-seeded rice.This study investigated the use of wood vinegar as a seed soaking treatment to enhance rice seedling rates under flooding ...Flooding stress is a major adverse condition during the emergence period of direct-seeded rice.This study investigated the use of wood vinegar as a seed soaking treatment to enhance rice seedling rates under flooding stress,exploring both the methodology and physiological mechanisms involved.The optimal seed soaking concentration was determined through a gradient experiment,followed by a multi-cultivar validation test.The physiological mechanism of wood vinegar soaking on seedling emergence was analyzed by measuring the electrical conductivity of the flooding water,the changes in starch and soluble sugar contents in the grains and sprouts,and the dynamics ofα-amylase activity and antioxidant-related enzyme activities in the sprouts.The results showed that soaking rice seeds in a wood vinegar solution at a low concentration significantly enhanced the emergence of rice seedlings under flooding conditions,with a 100-fold dilution having the most pronounced effect,increasing seedling rates by 50.6%-60.0%.Further analysis indicated that wood vinegar treatment enhanced seedling establishment by inducing a significant increase inα-amylase activity,leading to a 74.9%-213.6%increase in soluble sugar content in the sprouts during 2-8 d after flooding stress compared with the control.Additionally,the treatment increased superoxide dismutase and peroxidase activities in the sprouts,mitigating lipid peroxidation of the cell membranes,and notably lower water electrical conductivity was observed in wood vinegar-treated seeds compared with the control.In conclusion,soaking rice seeds in a 100-fold diluted wood vinegar solution improves rice seedling rates under flooding stress by mitigating oxidative damage and maintaining energy supply.This approach is valuable for developing cost-effective seed treatment technologies and offering novel strategies to improve seedling rates and uniformity of direct-seeded rice under flooding conditions.展开更多
Chilo suppressalis(Walker)is one of the most important rice pests worldwide,posing a significant challenge to effective control.To develop a precision-timed,eco-friendly management strategy,overwintering population in...Chilo suppressalis(Walker)is one of the most important rice pests worldwide,posing a significant challenge to effective control.To develop a precision-timed,eco-friendly management strategy,overwintering population investigation and dynamic monitoring of C.suppressalis populations were conducted in the Meishan region of Sichuan,China,from 2023 to 2024.The optimal timing for insecticide application was estimated,followed by field trials evaluating the efficacy of different insecticides.Results demonstrated that the peak emergence of first-generation adults typically occurred in early July(under the environmental conditions of the Meishan region),with the ambient humidity below 75%and temperature around 29◦C.Pesticide efficacy trials show that insecticide combinations exhibited superior control.Notably,a combined treatment of emamectin benzoate⋅methoxyfenozide+chlorantraniliprole achieved the highest control efficacy(90.05%)and a corresponding yield of 12,491.55 kg/ha.All tested treatments were determined to be safe for rice growth.Furthermore,this optimized strategy resulted in notable economic benefits,including a 50%reduction in pesticide usage and cost savings of 4796.15 CNY compared to conventional practices.This study provides valuable insights into sustainable rice production and pest management and,for the first time,proposes a precision application time window based on intelligent monitoring.展开更多
The NRAMP(natural resistance-associated macrophage protein)family plays a pivotal role in metal ion transport,regulating both essential micronutrient uptake and toxic heavy metal accumulation in plants.In rice(Oryza s...The NRAMP(natural resistance-associated macrophage protein)family plays a pivotal role in metal ion transport,regulating both essential micronutrient uptake and toxic heavy metal accumulation in plants.In rice(Oryza sativa),OsNRAMP transporters critically influence metal homeostasis,stress adaptation,and grain safety.Among them,OsNRAMP5 serves as a major entry point for cadmium(Cd)and manganese(Mn)uptake,making it a prime target for low-Cd rice breeding.However,knockout of OsNRAMP5 leads to severe Mn deficiency,highlighting the need for precise genetic modifications(e.g.,OsNRAMP5-Q337K),which reduce Cd accumulation while maintaining Mn nutrition.Additionally,OsNRAMP1 and OsNRAMP2 contribute to Cd translocation and plant immunity,whereas OsNRAMP3/4/6/7 participate in Mn,iron,and zinc distribution and stress responses.This review systematically summarizes the structural,functional,and regulatory mechanisms of OsNRAMPs,emphasizing their roles in metal transport,pathogen resistance,and abiotic stress adaptation.Furthermore,we discuss strategies for developing low-Cd rice varieties,including QTL-based breeding,CRISPR/Cas9-mediated gene editing,and multi-gene stacking approaches.Finally,we outline future research directions,such as structural engineering of metal-binding sites and field validation of engineered rice lines,to ensure sustainable rice production in heavy metal-contaminated soils.展开更多
CR Dhan 310(CRD310),a biofortified rice variety,contains a significantly higher level of grain protein compared with its recurrent parent Naveen(NV),as well as most adapted high-yielding rice varieties in India.Althou...CR Dhan 310(CRD310),a biofortified rice variety,contains a significantly higher level of grain protein compared with its recurrent parent Naveen(NV),as well as most adapted high-yielding rice varieties in India.Although a limited investigation depicted that CRD310 contained higher levels of glutelin and some essential amino acids,detailed biochemical,molecular,and cellular mechanisms remain to be studied.As one of the means to identify the proteins and understand the underlying mechanism of higher proteins accumulation in grains of CRD310,the comparative proteomics was undertaken on grains of CRD310 and NV at the yellow ripening stage.展开更多
Rice, a global staple food, is critical for food security. The cultivated Oryza sativa, domesticated from wild O. rufipogon, derives~80%of its 993 identified domestication-related genes from O. rufipogon and 20%from S...Rice, a global staple food, is critical for food security. The cultivated Oryza sativa, domesticated from wild O. rufipogon, derives~80%of its 993 identified domestication-related genes from O. rufipogon and 20%from South/Southeast Asian wild O. nivara(Jing et al., 2023). Genes like An-1, BH4, PROG1,SH4, Rc, Rd, and GS3—which regulate awn length, hull color,til er angle, seed shattering, pericarp color, seed length, and thousand-grain weight, respectively—were selected against during domestication to form modern O. sativa(Yu et al., 2021).However, domestication and yield-focused breeding eliminated wild rice's valuable genes(e.g., for disease resistance, stress tolerance, nutrition), narrowing genetic diversity and impeding efforts to meet growing societal demands.展开更多
Highlights OsCAX2 is localized to tonoplast,and cadmium induces its expression.OsCAX2 overexpression reduces cadmium concentration in indica rice grains by 49.1%.Cadmium(Cd)exposure poses significant health risks to h...Highlights OsCAX2 is localized to tonoplast,and cadmium induces its expression.OsCAX2 overexpression reduces cadmium concentration in indica rice grains by 49.1%.Cadmium(Cd)exposure poses significant health risks to humans,and the International Agency for Research on Cancer has classified it as a Group I carcinogen.Cadmium undergoes minimal metabolism in the human body;consequently,prolonged Cd^(2+)exposure can cause severe damage to multiple organs including the liver,kidneys,lungs,bones,and immune system(Shao et al.2024).Rice,one of the three global staple crops,and Cd exposure in humans primarily occurs the consumption of contaminated rice grains.The contribution of rice to the total dietary Cd intake is over 50% for non-smoking Asian populations(Chen et al.2018;Shi et al.2020).展开更多
Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confi...Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confirmed that OsADCS and OsGTPCHI,encoding the initial enzymes necessary for folate synthesis,positively regulate folate accumulation in knockout mutants of both japonica and indica rice backgrounds.The folate content in the low-folate japonica variety was slightly increased by the expression of the indica alleles driven by the endosperm-specific promoter.We further obtained co-expression lines by stacking OsADCS and OsGTPCHI genes;the folate accumulation in brown rice and polished rice reached 5.65μg/g and 2.95μg/g,respectively,representing 37.9-fold and 26.5-fold increases compared with the wild type.Transcriptomic analysis of rice grains from six transgenic lines showed that folate changes affected biological pathways involved in the synthesis and metabolism of rice seed storage substances,while the expression of other folate synthesis genes was weakly regulated.In addition,we identified Aus rice as a high-folate germplasm carrying superior haplotypes of OsADCS and OsGTPCHI through natural variation.This study provides an alternative and effective complementary strategy for rice biofortification,promoting the rational combination of metabolic engineering and conventional breeding to breed high-folate varieties.展开更多
Rice yield is heavily reliant on the number of spikelets per panicle,a factor determined by the processes of spikelet differentiation and degeneration.In rice cultivars with large panicles,spikelet degeneration negate...Rice yield is heavily reliant on the number of spikelets per panicle,a factor determined by the processes of spikelet differentiation and degeneration.In rice cultivars with large panicles,spikelet degeneration negates the advantages of large panicle and constrains yield potential.Environmental stress-induced metabolic disorders in plants aggravate spikelet degeneration,with the sensitive period for this process commencing approximately 15‒20 d before panicle heading.Notable positional variations occur within the panicle,with significantly higher spikelet degeneration rates at the basal than at the upper positions.An imbalance of carbon and nitrogen metabolism represents the primary physiological basis for aggravated spikelet degeneration under abiotic stress.Impaired carbon and nitrogen metabolism leads to disordered energy metabolism and disrupted respiratory electron transport,which accelerates the apoptosis of young spikelets through excessive reactive oxygen species accumulation.Sucrose serves as the main carbohydrate source for spikelet development,demonstrating an apical dominance pattern that favors spikelet formation.However,under abiotic stress,the inhibition of sucrose decomposition,rather than sucrose transport impairment,predominantly contributes to aggravated spikelet degeneration at the basal panicle positions.Brassinolide and auxin have a significant relationship with spikelet formation,potentially mediating apical dominance.Specifically,brassinolide enhances sucrose accumulation and utilization,thereby alleviating spikelet degeneration.At present,the mechanisms underlying rice spikelet degeneration have not been fully revealed,and the joint effects of hormones,carbohydrates,and carbon and nitrogen metabolism on this process require further investigation.To reduce the spikelet degeneration,the strategic application of water and fertilizer to establish a stable rice population can enhance the rice plants’resilience to abiotic stress.An effective approach to reducing spikelet degeneration is to increase the dry matter occupancy of each spikelet during the panicle initiation period.展开更多
Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of f...Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of fungicides for managing rice seedling blight,there has been a shift in focus towards biological control agents.In this study,we isolated biocontrol bacteria from paddy fields that significantly inhibited the growth of F.oxysporum in vitro and identified the strains as Bacillus amyloliquefaciens T40 and Bacillus pumilus T208.Additionally,our findings indicated that the combined application of these Bacillus strains in soil was more effective in reducing the incidence of rice seedling blight than their individual use.Analysis of 16S and internal transcribed spacer rRNA gene sequencing data revealed that the mixture of the T40 and T208 strains exhibited the lowest average clustering coefficients,which were negatively correlated with the biomass of F.oxysporum-inoculated rice seedlings.Furthermore,this mixture led to higher stochastic assembly(average|βNTI|<2)and reduced selection pressures on rice rhizosphere bacteria compared with individual strain applications.The mixture of the T40 and T208 strains also significantly increased the expression of defense-related genes.In conclusion,the mixture of the T40 and T208 strains effectively modulates microbial community structures,enhances microbial network stability,and boosts the resistance against rice seedling blight.Our study supports the development and utilization of biological resources for crop protection.展开更多
Rice crops are frequently threatened by pests such as rice planthoppers(Nilaparvata lugens,Sogatella furcifera,and Laodelphax striatellus)and leafhoppers(Cicadellidae),which cause significant yield losses.Accurate ide...Rice crops are frequently threatened by pests such as rice planthoppers(Nilaparvata lugens,Sogatella furcifera,and Laodelphax striatellus)and leafhoppers(Cicadellidae),which cause significant yield losses.Accurate identification of both pest developmental stages and their natural predators is crucial for effective pest control and maintaining ecological balance.However,conventional field surveys are often subjective,inefficient,and lack traceability.To overcome these limitations,this study proposed RiceInsectID,a two-stage cascaded detection method designed to identify and count tiny rice pests and their natural predators from white flat plate images captured by head-worn AR glasses.The method recognizes 25 insect classes,including 17 instars of rice planthoppers,2 instars of leafhoppers,4 spider species(Araneae),as well as Miridae and rove beetles(Staphylinidae Latreille).At the first coarse-grained detection stage,16 visually similar classes are consolidated into 6 broader categories and detected using an enhanced YOLOv6 model.To improve small object detection and address class imbalance,the fullregion overlapping sliding slices and target pasting(FOSTP)algorithm was applied,increasing the mean average precision at a 50%IoU threshold(mAP50)by 35.46%over the baseline YOLOv6.Feature extraction and fusion were further improved by incorporating an efficient channel attention path aggregation feature pyramid network(ECA-PAFPN)and adaptive structure feature fusion(ASFF)modules,while the balanced classification mosaic(BCM)enhanced detection of minority classes.With test-time augmentation(TTA),mAP50 improved by an additional 2.06%,reaching 84.71%.At the second fine-grained classification stage,each of the six broad classes from the first stage is further classified using individual ResNet50 models.Online data augmentation and transfer learning were employed to significantly enhance generalization.Compared with the baseline YOLOv6,the two-stage cascaded method improved recall by 4.06%,precision by 3.79%,and the F1-score by 3.92%.Overall,RiceInsectID achieved 82.85%recall,80.62%precision,and an F1-score of 81.72%,demonstrating an efficient and practical solution for monitoring tiny rice pests and their natural predators in paddy fields.This study provides valuable insights for ecosystem monitoring and supporting sustainable pest management in rice agriculture.展开更多
Rice sheath blight(RSB)is a major destructive disease impeding rice production.Identifying key germplasm resources with increased resistance remains a challenge.However,the mechanisms underlying disease resistance are...Rice sheath blight(RSB)is a major destructive disease impeding rice production.Identifying key germplasm resources with increased resistance remains a challenge.However,the mechanisms underlying disease resistance are not yet fully understood.Cytochrome P450 monooxygenases(CYP450s)serve biosynthesis and metabolic detoxification functions in plants,but there is limited information about their role in the response induced by RSB.This study demonstrated that CYT02 belongs to the CYP73A100 subfamily and is a typical member of the CYP450s.Overexpression(OE)in rice of the cytochrome P450 monooxygenase cyt02 conferred increased resistance to RSB and increased vegetative tillering.Cyt02 may increase RSB resistance by regulating plant hormone synthesis,regulate reactive oxygen species(ROS)by coordinating the activity of antioxidant enzymes,and initiate phytoalexin synthesis in response to fungal infection.These research findings have laid a foundation for a deeper understanding of the function of cyt02 and offered a potential target gene for breeding rice varieties resistant to sheath blight.展开更多
The ratooning system enhances agricultural efficiency by reducing secondary sowing and resource input while maintaining rice yield parity with double cropping.However,the prolonged growth duration of the rice ratoonin...The ratooning system enhances agricultural efficiency by reducing secondary sowing and resource input while maintaining rice yield parity with double cropping.However,the prolonged growth duration of the rice ratooning system extends the exposure window to Magnaporthe oryzae infection,thereby elevating the probability of disease incidence.展开更多
Doubled haploid(DH)technology has revolutionized crop breeding by enabling the production of homozygous lines in a single generation.In vivo haploid induction(HI)offers a more widely applicable approach that can signi...Doubled haploid(DH)technology has revolutionized crop breeding by enabling the production of homozygous lines in a single generation.In vivo haploid induction(HI)offers a more widely applicable approach that can significantly improve DH breeding efficiency.ToPAR,a parthenogenesis gene,originally identified in dandelion(Taraxacum officinale),has been characterized.Researchers have successfully induced haploid embryo-like structures and haploid offspring in lettuce and foxtail millet,respectively.展开更多
Global warming poses a severe threat to rice production and food security.We identified a heat-sensitive mutant hs1 through largescale screening of an established rice mutant library,and subsequently cloned the corres...Global warming poses a severe threat to rice production and food security.We identified a heat-sensitive mutant hs1 through largescale screening of an established rice mutant library,and subsequently cloned the corresponding gene HS1,which confers thermotolerance in rice.HS1 is localized to the chloroplast and functions by preserving chloroplast integrity under elevated temperatures through stabilizing the photosystem I subunit protein PsaC.Loss of HS1 function in the hs1 mutant leads to severe structural damage to the chloroplast under heat stress,accompanied by intracellular accumulation of reactive oxygen species(ROS),which in turn triggers DNA damage and leaf albinism,ultimately manifesting as a heat-sensitive phenotype.展开更多
In rice fields,rice plants usually grow alongside wild weeds and are attacked by various invertebrate species.Viruses are abundant in plants and invertebrates,playing crucial ecological roles in controlling microbial ...In rice fields,rice plants usually grow alongside wild weeds and are attacked by various invertebrate species.Viruses are abundant in plants and invertebrates,playing crucial ecological roles in controlling microbial abundance and maintaining community structures.To date,only 16 rice viruses have been documented in rice-growing regions.These viruses pose serious threats to rice production and have traditionally been identified only from rice plants and insect vectors by isolation techniques.Advances in next-generation sequencing(NGS)have made it feasible to discover viruses on a global scale.Recently,numerous viruses have been identified in plants and invertebrates using NGS technologies.In this review,we discuss viral studies in rice plants,invertebrate species,and weeds in rice fields.Many novel viruses have been discovered in rice ecosystems through NGS technologies,with some also detected using metatranscriptomic and small RNA sequencing.These analyses greatly expand our understanding of viruses in rice fields and provide valuable insights for developing efficient strategies to manage insect pests and virus-mediated rice diseases.展开更多
Rice seed germination marks the start of cultivation and influences subsequent seedling growth,and is affected by hormones and environmental factors.Ubiquitination plays a critical role in this process by regulating h...Rice seed germination marks the start of cultivation and influences subsequent seedling growth,and is affected by hormones and environmental factors.Ubiquitination plays a critical role in this process by regulating hormonal homeostasis.In the ubiquitination cascade,ubiquitin-conjugating enzymes(UBCs)function as ubiquitin carriers to determine linkage specificity of ubiquitin chains.In rice(Oryza sativa),39 UBC genes are identified,but only one gene OsUBC12 has been functionally studied to promote seed germination under low-temperatures in japonica rice.To elucidate the role of UBCs in seed germination,we generated CRISPR-Cas9 mutants for 23 UBC genes and overexpressed 20 members in rice.Among them,seven UBC genes(OsUBC4/6/7/12/25/27/48)were found to regulate seed germination,with OsUBC27 and OsUBC48 acting through the ABA pathway.Exogenous ABA inhibitors restored the germination rate of osubc27^(CR).RT-qPCR analysis revealed that the ABA synthesis genes OsNCED1-5 were significantly upregulated in the mutants.Further differential ubiquitination proteomics in knockout mutants and wild-type plants showed that OsUBC27 regulates ABA homeostasis by modulating ubiquitination of the ABA-degrading protein OsABA8ox1,thereby balancing seed dormancy and germination.Sequence analysis identified distinct haplotypes of the seven OsUBCs that showed differential distribution between japonica and indica subspecies.Our study provides valuable molecular targets for developing rice varieties resistant to seed vivipary.展开更多
In natural ecosystems,the timely abscission of seeds in wild plants is a crucial adaptive trait that contributes to reproductive success,population renewal,and colony expansion(Thurber et al.2010).In contrast,the tend...In natural ecosystems,the timely abscission of seeds in wild plants is a crucial adaptive trait that contributes to reproductive success,population renewal,and colony expansion(Thurber et al.2010).In contrast,the tendency for high seed shattering in domesticated crops,such as rice,not only reduces paddy yield but also complicates mechanized harvesting.展开更多
Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,...Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,Sub1 and Dro1(Δbp:10 Mb),as well as Sub1 and TPP7(Δbp:6 Mb)were identified to exhibit long-range linkage disequilibrium(LRLD).Meta-QTL analysis further revealed that Sub1 and TPP7 co-segregated for tolerance to submergence at the germination and seedling stages.Based on this,we hypothesized that LRLD might influence plant responses to consecutive stresses.To test this hypothesis,we developed a structured recombinant inbred line population from a cross between Bhalum 2 and Nagina 22,with alleles(Sub1 and TPP7)in linkage equilibrium.Mendelian randomization analysis validated that the parental alleles,rather than the recombinant alleles of Sub1 and TPP7,significantly influenced 13 out of 41 traits under consecutive stress conditions.Additionally,16 minor additive effect QTLs were detected between the genomic regions,spanning Sub1 and TPP7 for various traits.A single allele difference between these genomic regions enhanced crown root number,root dry weight,and specific root area by 11.45%,15.69%,and 33.15%,respectively,under flooded germination conditions.Candidate gene analysis identified WAK79 and MRLK59 as regulators of stress responses during flooded germination,recovery,and subsequent water deficit conditions.These findings highlight the critical role of parental allele combinations and genomic regions between Sub1 and TPP7 in regulating the stress responses under consecutive stresses.Favourable haplotypes derived from these alleles can be utilized to improve stress resilience in direct-seeded rice.展开更多
Sucrose transporters(SUTs)contain multiple transmembrane domains that mediate sucrose transport and provide energy for plant growth and development.However,the role of OsSUTs in regulating rice quality and grain yield...Sucrose transporters(SUTs)contain multiple transmembrane domains that mediate sucrose transport and provide energy for plant growth and development.However,the role of OsSUTs in regulating rice quality and grain yield remains unclear.In this study,we identified five rice SUT genes(OsSUT1-OsSUT5)and examined their molecular characteristics and biological functions.OsSUT1,OsSUT2,and OsSUT4 were predominantly expressed in stems,while OsSUT3 and OsSUT5 showed higher expression in panicles.OsSUT1 and OsSUT4 are located on the plasma membrane,whereas OsSUT2,OsSUT3,and OsSUT5 are localized to the tonoplast.展开更多
The leaf is a major organ for photosynthesis,and its shape plays an important role in plant development and yield determination in rice(Oryza sativa L.).In this study,an adaxial curled leaf mutant,termed curly leaf 1-...The leaf is a major organ for photosynthesis,and its shape plays an important role in plant development and yield determination in rice(Oryza sativa L.).In this study,an adaxial curled leaf mutant,termed curly leaf 1-1(cul1-1),was obtained by chemical mutagenesis.The leaf rolling index of the cul1-1 mutant was higher than that of the wild-type,which was caused by the abnormal development of bulliform cells(BCs).We cloned the CUL1 gene by map-based cloning.A nonsense mutation was present in the cul1-1 mutant,converting a tryptophan codon into a stop codon.The CUL1 gene encodes a chromodomain,helicase/ATPase and DNA-binding domain containing protein.Genes related to leaf rolling and BC development,such as ADL1,REL1 and ROC5,were activated by the cul1-1 mutation.The trimethylation of lysine 27 in histone 3(H3K27me3),but not H3K4me3,at the ADL1,REL1 and ROC5 loci,was reduced in the cul1-1 mutant.High-throughput mRNA sequencing indicated that the cul1-1 mutation caused genome-wide differential gene expression.The differentially expressed genes were classified into a few gene ontology terms and Kyoto encyclopedia of genes and genomes pathways.In the natural population,22 missense genomic variations in the CUL1 locus were identified,which composed of 7 haplotypes.A haplotype network was also built with haplotype II as the ancestor.The findings revealed that CUL1 is essential for normal leaf development and regulates this process by inhibiting the expression of genes involved in leaf rolling and BC development.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2023YFD2301300)the National Rice Industry Technology System,China(Grant No.CARS-01).
文摘Flooding stress is a major adverse condition during the emergence period of direct-seeded rice.This study investigated the use of wood vinegar as a seed soaking treatment to enhance rice seedling rates under flooding stress,exploring both the methodology and physiological mechanisms involved.The optimal seed soaking concentration was determined through a gradient experiment,followed by a multi-cultivar validation test.The physiological mechanism of wood vinegar soaking on seedling emergence was analyzed by measuring the electrical conductivity of the flooding water,the changes in starch and soluble sugar contents in the grains and sprouts,and the dynamics ofα-amylase activity and antioxidant-related enzyme activities in the sprouts.The results showed that soaking rice seeds in a wood vinegar solution at a low concentration significantly enhanced the emergence of rice seedlings under flooding conditions,with a 100-fold dilution having the most pronounced effect,increasing seedling rates by 50.6%-60.0%.Further analysis indicated that wood vinegar treatment enhanced seedling establishment by inducing a significant increase inα-amylase activity,leading to a 74.9%-213.6%increase in soluble sugar content in the sprouts during 2-8 d after flooding stress compared with the control.Additionally,the treatment increased superoxide dismutase and peroxidase activities in the sprouts,mitigating lipid peroxidation of the cell membranes,and notably lower water electrical conductivity was observed in wood vinegar-treated seeds compared with the control.In conclusion,soaking rice seeds in a 100-fold diluted wood vinegar solution improves rice seedling rates under flooding stress by mitigating oxidative damage and maintaining energy supply.This approach is valuable for developing cost-effective seed treatment technologies and offering novel strategies to improve seedling rates and uniformity of direct-seeded rice under flooding conditions.
基金funded by the National Key R&D Project‘Innovation and Integration of Key Technologies for Integration of Agricultural Machinery and Agronomy in Weak Links of Hybrid Mid-season Rice in Hilly Areas of Southwest China’(2023YFD2301901).
文摘Chilo suppressalis(Walker)is one of the most important rice pests worldwide,posing a significant challenge to effective control.To develop a precision-timed,eco-friendly management strategy,overwintering population investigation and dynamic monitoring of C.suppressalis populations were conducted in the Meishan region of Sichuan,China,from 2023 to 2024.The optimal timing for insecticide application was estimated,followed by field trials evaluating the efficacy of different insecticides.Results demonstrated that the peak emergence of first-generation adults typically occurred in early July(under the environmental conditions of the Meishan region),with the ambient humidity below 75%and temperature around 29◦C.Pesticide efficacy trials show that insecticide combinations exhibited superior control.Notably,a combined treatment of emamectin benzoate⋅methoxyfenozide+chlorantraniliprole achieved the highest control efficacy(90.05%)and a corresponding yield of 12,491.55 kg/ha.All tested treatments were determined to be safe for rice growth.Furthermore,this optimized strategy resulted in notable economic benefits,including a 50%reduction in pesticide usage and cost savings of 4796.15 CNY compared to conventional practices.This study provides valuable insights into sustainable rice production and pest management and,for the first time,proposes a precision application time window based on intelligent monitoring.
基金supported by the National Key R&D Program,China(Grant No.2022YFD1201505)the Key Laboratory of Sichuan Province Open Project,China(Grant No.2023LYKF02)+1 种基金the Central Public-Interest Scientific Institution Basal Research Fund,China(Grant No.CPSIBRF-CNRRI-202306)the Sichuan Provincial Financial Independent Innovation Project,China(Grant No.2022ZZCX001).
文摘The NRAMP(natural resistance-associated macrophage protein)family plays a pivotal role in metal ion transport,regulating both essential micronutrient uptake and toxic heavy metal accumulation in plants.In rice(Oryza sativa),OsNRAMP transporters critically influence metal homeostasis,stress adaptation,and grain safety.Among them,OsNRAMP5 serves as a major entry point for cadmium(Cd)and manganese(Mn)uptake,making it a prime target for low-Cd rice breeding.However,knockout of OsNRAMP5 leads to severe Mn deficiency,highlighting the need for precise genetic modifications(e.g.,OsNRAMP5-Q337K),which reduce Cd accumulation while maintaining Mn nutrition.Additionally,OsNRAMP1 and OsNRAMP2 contribute to Cd translocation and plant immunity,whereas OsNRAMP3/4/6/7 participate in Mn,iron,and zinc distribution and stress responses.This review systematically summarizes the structural,functional,and regulatory mechanisms of OsNRAMPs,emphasizing their roles in metal transport,pathogen resistance,and abiotic stress adaptation.Furthermore,we discuss strategies for developing low-Cd rice varieties,including QTL-based breeding,CRISPR/Cas9-mediated gene editing,and multi-gene stacking approaches.Finally,we outline future research directions,such as structural engineering of metal-binding sites and field validation of engineered rice lines,to ensure sustainable rice production in heavy metal-contaminated soils.
基金supported by the director of Indian Council of Agricultural Research and International Rice Research Institute (ICAR-CRRI), Cuttack, Indiathe coordinator of the ICAR-sponsored project ‘C-reactive protein (CRP) in Biofortification in Selected Crops’, India
文摘CR Dhan 310(CRD310),a biofortified rice variety,contains a significantly higher level of grain protein compared with its recurrent parent Naveen(NV),as well as most adapted high-yielding rice varieties in India.Although a limited investigation depicted that CRD310 contained higher levels of glutelin and some essential amino acids,detailed biochemical,molecular,and cellular mechanisms remain to be studied.As one of the means to identify the proteins and understand the underlying mechanism of higher proteins accumulation in grains of CRD310,the comparative proteomics was undertaken on grains of CRD310 and NV at the yellow ripening stage.
基金supported by the Biological BreedingMajor Projects(2023ZD04076)the National Natural Science Foundation of China(32300312)+2 种基金the Innovation Program of Chinses Academy of Agricultural Sciences(CAAS-CSIAF-202303)the Guangdong Basic and Applied Basic Research Foundation(2020B1515120086)the KeyArea Research and Development Program of Guangdong Province(2021B0707010006)。
文摘Rice, a global staple food, is critical for food security. The cultivated Oryza sativa, domesticated from wild O. rufipogon, derives~80%of its 993 identified domestication-related genes from O. rufipogon and 20%from South/Southeast Asian wild O. nivara(Jing et al., 2023). Genes like An-1, BH4, PROG1,SH4, Rc, Rd, and GS3—which regulate awn length, hull color,til er angle, seed shattering, pericarp color, seed length, and thousand-grain weight, respectively—were selected against during domestication to form modern O. sativa(Yu et al., 2021).However, domestication and yield-focused breeding eliminated wild rice's valuable genes(e.g., for disease resistance, stress tolerance, nutrition), narrowing genetic diversity and impeding efforts to meet growing societal demands.
基金financially supported by the National Key R&D Program of China(2024YFD1200800)the Guangdong Basic and Applied Basic Research Foundation,China(2024A1515030094)。
文摘Highlights OsCAX2 is localized to tonoplast,and cadmium induces its expression.OsCAX2 overexpression reduces cadmium concentration in indica rice grains by 49.1%.Cadmium(Cd)exposure poses significant health risks to humans,and the International Agency for Research on Cancer has classified it as a Group I carcinogen.Cadmium undergoes minimal metabolism in the human body;consequently,prolonged Cd^(2+)exposure can cause severe damage to multiple organs including the liver,kidneys,lungs,bones,and immune system(Shao et al.2024).Rice,one of the three global staple crops,and Cd exposure in humans primarily occurs the consumption of contaminated rice grains.The contribution of rice to the total dietary Cd intake is over 50% for non-smoking Asian populations(Chen et al.2018;Shi et al.2020).
基金supported by the Central Public-Interest Scientific Institution Basal Research Fund,China(Grant No.CPSIBRF-CNRRI-202403)。
文摘Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confirmed that OsADCS and OsGTPCHI,encoding the initial enzymes necessary for folate synthesis,positively regulate folate accumulation in knockout mutants of both japonica and indica rice backgrounds.The folate content in the low-folate japonica variety was slightly increased by the expression of the indica alleles driven by the endosperm-specific promoter.We further obtained co-expression lines by stacking OsADCS and OsGTPCHI genes;the folate accumulation in brown rice and polished rice reached 5.65μg/g and 2.95μg/g,respectively,representing 37.9-fold and 26.5-fold increases compared with the wild type.Transcriptomic analysis of rice grains from six transgenic lines showed that folate changes affected biological pathways involved in the synthesis and metabolism of rice seed storage substances,while the expression of other folate synthesis genes was weakly regulated.In addition,we identified Aus rice as a high-folate germplasm carrying superior haplotypes of OsADCS and OsGTPCHI through natural variation.This study provides an alternative and effective complementary strategy for rice biofortification,promoting the rational combination of metabolic engineering and conventional breeding to breed high-folate varieties.
基金funded by the National Natural Science Foundation of China(Grant No.32201896)the Zhejiang Province Key Research and Development Plan Project,China(Grant No.2022C02034)the National Modern Agricultural Industrial Technology System Construction Project,China(Grant No.CARS-01-21).
文摘Rice yield is heavily reliant on the number of spikelets per panicle,a factor determined by the processes of spikelet differentiation and degeneration.In rice cultivars with large panicles,spikelet degeneration negates the advantages of large panicle and constrains yield potential.Environmental stress-induced metabolic disorders in plants aggravate spikelet degeneration,with the sensitive period for this process commencing approximately 15‒20 d before panicle heading.Notable positional variations occur within the panicle,with significantly higher spikelet degeneration rates at the basal than at the upper positions.An imbalance of carbon and nitrogen metabolism represents the primary physiological basis for aggravated spikelet degeneration under abiotic stress.Impaired carbon and nitrogen metabolism leads to disordered energy metabolism and disrupted respiratory electron transport,which accelerates the apoptosis of young spikelets through excessive reactive oxygen species accumulation.Sucrose serves as the main carbohydrate source for spikelet development,demonstrating an apical dominance pattern that favors spikelet formation.However,under abiotic stress,the inhibition of sucrose decomposition,rather than sucrose transport impairment,predominantly contributes to aggravated spikelet degeneration at the basal panicle positions.Brassinolide and auxin have a significant relationship with spikelet formation,potentially mediating apical dominance.Specifically,brassinolide enhances sucrose accumulation and utilization,thereby alleviating spikelet degeneration.At present,the mechanisms underlying rice spikelet degeneration have not been fully revealed,and the joint effects of hormones,carbohydrates,and carbon and nitrogen metabolism on this process require further investigation.To reduce the spikelet degeneration,the strategic application of water and fertilizer to establish a stable rice population can enhance the rice plants’resilience to abiotic stress.An effective approach to reducing spikelet degeneration is to increase the dry matter occupancy of each spikelet during the panicle initiation period.
基金supported by the Zhejiang Provincial Natural Science Foundation,China(Grant No.LQ24C010007)Zhejiang Science and Technology Major Program on Rice New Variety Breeding,China(Grant No.2021C02063)+4 种基金the Agricultural Sciences and Technologies Innovation Program,China(Grant No.CAAS-CSCB-202301)the Key Projects of Zhejiang Provincial Natural Science Foundation,China(Grant No.LZ23C130002)the Youth Innovation Program of Chinese Academy of Agricultural Sciences(Grant No.Y2023QC22)the Joint Open Competitive Project of the Yazhou Bay Seed Laboratory and China National Seed Company Limited(Grant Nos.B23YQ1514 and B23CQ15EP)the External Cooperation Projects of Biotechnology Research Institute,Fujian Academy of Agricultural Sciences,China(Grant No.DWHZ2024-07).
文摘Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of fungicides for managing rice seedling blight,there has been a shift in focus towards biological control agents.In this study,we isolated biocontrol bacteria from paddy fields that significantly inhibited the growth of F.oxysporum in vitro and identified the strains as Bacillus amyloliquefaciens T40 and Bacillus pumilus T208.Additionally,our findings indicated that the combined application of these Bacillus strains in soil was more effective in reducing the incidence of rice seedling blight than their individual use.Analysis of 16S and internal transcribed spacer rRNA gene sequencing data revealed that the mixture of the T40 and T208 strains exhibited the lowest average clustering coefficients,which were negatively correlated with the biomass of F.oxysporum-inoculated rice seedlings.Furthermore,this mixture led to higher stochastic assembly(average|βNTI|<2)and reduced selection pressures on rice rhizosphere bacteria compared with individual strain applications.The mixture of the T40 and T208 strains also significantly increased the expression of defense-related genes.In conclusion,the mixture of the T40 and T208 strains effectively modulates microbial community structures,enhances microbial network stability,and boosts the resistance against rice seedling blight.Our study supports the development and utilization of biological resources for crop protection.
基金supported by the National Key Research Program of China during the 14th Five-Year Plan Period(Grant No.2021YFD1401100)the Zhejiang Provincial Natural Science Foundation of China(Grant No.LTGN24C140007)the‘San Nong Jiu Fang’Sciences and Technologies Cooperation Project of Zhejiang Province,China(Grant No.2024SNJF010)。
文摘Rice crops are frequently threatened by pests such as rice planthoppers(Nilaparvata lugens,Sogatella furcifera,and Laodelphax striatellus)and leafhoppers(Cicadellidae),which cause significant yield losses.Accurate identification of both pest developmental stages and their natural predators is crucial for effective pest control and maintaining ecological balance.However,conventional field surveys are often subjective,inefficient,and lack traceability.To overcome these limitations,this study proposed RiceInsectID,a two-stage cascaded detection method designed to identify and count tiny rice pests and their natural predators from white flat plate images captured by head-worn AR glasses.The method recognizes 25 insect classes,including 17 instars of rice planthoppers,2 instars of leafhoppers,4 spider species(Araneae),as well as Miridae and rove beetles(Staphylinidae Latreille).At the first coarse-grained detection stage,16 visually similar classes are consolidated into 6 broader categories and detected using an enhanced YOLOv6 model.To improve small object detection and address class imbalance,the fullregion overlapping sliding slices and target pasting(FOSTP)algorithm was applied,increasing the mean average precision at a 50%IoU threshold(mAP50)by 35.46%over the baseline YOLOv6.Feature extraction and fusion were further improved by incorporating an efficient channel attention path aggregation feature pyramid network(ECA-PAFPN)and adaptive structure feature fusion(ASFF)modules,while the balanced classification mosaic(BCM)enhanced detection of minority classes.With test-time augmentation(TTA),mAP50 improved by an additional 2.06%,reaching 84.71%.At the second fine-grained classification stage,each of the six broad classes from the first stage is further classified using individual ResNet50 models.Online data augmentation and transfer learning were employed to significantly enhance generalization.Compared with the baseline YOLOv6,the two-stage cascaded method improved recall by 4.06%,precision by 3.79%,and the F1-score by 3.92%.Overall,RiceInsectID achieved 82.85%recall,80.62%precision,and an F1-score of 81.72%,demonstrating an efficient and practical solution for monitoring tiny rice pests and their natural predators in paddy fields.This study provides valuable insights for ecosystem monitoring and supporting sustainable pest management in rice agriculture.
基金supported by the Sichuan Province International Science and Technology Innovation Cooperation(2024YFHZ0299)the Project of Science and Technology Department of Sichuan Province(2022YFH0031)Chengdu Science and Technology Bureau(2024-YF05-02168-SN).
文摘Rice sheath blight(RSB)is a major destructive disease impeding rice production.Identifying key germplasm resources with increased resistance remains a challenge.However,the mechanisms underlying disease resistance are not yet fully understood.Cytochrome P450 monooxygenases(CYP450s)serve biosynthesis and metabolic detoxification functions in plants,but there is limited information about their role in the response induced by RSB.This study demonstrated that CYT02 belongs to the CYP73A100 subfamily and is a typical member of the CYP450s.Overexpression(OE)in rice of the cytochrome P450 monooxygenase cyt02 conferred increased resistance to RSB and increased vegetative tillering.Cyt02 may increase RSB resistance by regulating plant hormone synthesis,regulate reactive oxygen species(ROS)by coordinating the activity of antioxidant enzymes,and initiate phytoalexin synthesis in response to fungal infection.These research findings have laid a foundation for a deeper understanding of the function of cyt02 and offered a potential target gene for breeding rice varieties resistant to sheath blight.
基金supported by the Key Research and Development Program Project of Hunan Province, China (Grant No. 2023NK2003)the National Key Research and Development Program of China (Grant No. 2022YFD2301001-03)the National Key Research and Development Program of China (Grant No. 2022YFD2301003)
文摘The ratooning system enhances agricultural efficiency by reducing secondary sowing and resource input while maintaining rice yield parity with double cropping.However,the prolonged growth duration of the rice ratooning system extends the exposure window to Magnaporthe oryzae infection,thereby elevating the probability of disease incidence.
基金supported by the Nanfan Special Project of the Chinese Academy of Agricultural Sciences(Grant Nos.YBXM2320 and YBXM2433)the Project of Sanya Yazhou Bay Science and Technology City,China(Grant No.SCKJ-JYRC-2024-58)the Agricultural Science and Technology Innovation Program,China(Grant No.CAAS-ASTIP-2021-CNRRI).
文摘Doubled haploid(DH)technology has revolutionized crop breeding by enabling the production of homozygous lines in a single generation.In vivo haploid induction(HI)offers a more widely applicable approach that can significantly improve DH breeding efficiency.ToPAR,a parthenogenesis gene,originally identified in dandelion(Taraxacum officinale),has been characterized.Researchers have successfully induced haploid embryo-like structures and haploid offspring in lettuce and foxtail millet,respectively.
基金supported by the National Natural Science Foundation of China(Grant Nos.32372118 and 32188102)the Zhejiang Natural Science Foundation,China(Grant No.LZ25C130010)+1 种基金the Qian Qian Academician Workstation,and the specific research fund of the Innovation Platform for Academicians of Hainan Province,China(Grant No.YSPTZX202303)the Central Public-Interest Scientific Institution Basal Research Fund from Chinese Academy of Agricultural Sciences(Grant No.Y2025YC93)。
文摘Global warming poses a severe threat to rice production and food security.We identified a heat-sensitive mutant hs1 through largescale screening of an established rice mutant library,and subsequently cloned the corresponding gene HS1,which confers thermotolerance in rice.HS1 is localized to the chloroplast and functions by preserving chloroplast integrity under elevated temperatures through stabilizing the photosystem I subunit protein PsaC.Loss of HS1 function in the hs1 mutant leads to severe structural damage to the chloroplast under heat stress,accompanied by intracellular accumulation of reactive oxygen species(ROS),which in turn triggers DNA damage and leaf albinism,ultimately manifesting as a heat-sensitive phenotype.
基金supported by the National Natural Science Foundation of China(Grant Nos.31972983 and 32072487)the Key Technology R&D Program of Zhejiang Province,China(Grant No.2021C02006)the Zhejiang Provincial Natural Science Foundation of China(Grant No.LY23C140001).
文摘In rice fields,rice plants usually grow alongside wild weeds and are attacked by various invertebrate species.Viruses are abundant in plants and invertebrates,playing crucial ecological roles in controlling microbial abundance and maintaining community structures.To date,only 16 rice viruses have been documented in rice-growing regions.These viruses pose serious threats to rice production and have traditionally been identified only from rice plants and insect vectors by isolation techniques.Advances in next-generation sequencing(NGS)have made it feasible to discover viruses on a global scale.Recently,numerous viruses have been identified in plants and invertebrates using NGS technologies.In this review,we discuss viral studies in rice plants,invertebrate species,and weeds in rice fields.Many novel viruses have been discovered in rice ecosystems through NGS technologies,with some also detected using metatranscriptomic and small RNA sequencing.These analyses greatly expand our understanding of viruses in rice fields and provide valuable insights for developing efficient strategies to manage insect pests and virus-mediated rice diseases.
基金supported by the Zhejiang Provincial Natural Science Foundation,China(ZCLMS25C1302)the Central Public-interest Scientific Institution Basal Research Fund(CPSIBRF-CNRRI-202408)the Agricultural Science and Technology Innovation Program(ASTIP)
文摘Rice seed germination marks the start of cultivation and influences subsequent seedling growth,and is affected by hormones and environmental factors.Ubiquitination plays a critical role in this process by regulating hormonal homeostasis.In the ubiquitination cascade,ubiquitin-conjugating enzymes(UBCs)function as ubiquitin carriers to determine linkage specificity of ubiquitin chains.In rice(Oryza sativa),39 UBC genes are identified,but only one gene OsUBC12 has been functionally studied to promote seed germination under low-temperatures in japonica rice.To elucidate the role of UBCs in seed germination,we generated CRISPR-Cas9 mutants for 23 UBC genes and overexpressed 20 members in rice.Among them,seven UBC genes(OsUBC4/6/7/12/25/27/48)were found to regulate seed germination,with OsUBC27 and OsUBC48 acting through the ABA pathway.Exogenous ABA inhibitors restored the germination rate of osubc27^(CR).RT-qPCR analysis revealed that the ABA synthesis genes OsNCED1-5 were significantly upregulated in the mutants.Further differential ubiquitination proteomics in knockout mutants and wild-type plants showed that OsUBC27 regulates ABA homeostasis by modulating ubiquitination of the ABA-degrading protein OsABA8ox1,thereby balancing seed dormancy and germination.Sequence analysis identified distinct haplotypes of the seven OsUBCs that showed differential distribution between japonica and indica subspecies.Our study provides valuable molecular targets for developing rice varieties resistant to seed vivipary.
基金supported by the National Natural Science Foundation of China(32372118 and 32188102)the Qian Qian Academician Workstation,China+3 种基金the Specific Research Fund of the Innovation Platform for Academicians of Hainan Province,China(YSPTZX202303)the Nanfan Special Project,Chinese Academy of Agricultural Sciences(ZDXM2315)the Chinese Academy of Agricultural Sciences Talent Plan-Outstanding Young Talentthe Zhejiang Province’s High-level Talent Special Support Plan-Young Talent,China。
文摘In natural ecosystems,the timely abscission of seeds in wild plants is a crucial adaptive trait that contributes to reproductive success,population renewal,and colony expansion(Thurber et al.2010).In contrast,the tendency for high seed shattering in domesticated crops,such as rice,not only reduces paddy yield but also complicates mechanized harvesting.
基金supported by the Director General,Indian Council of Agricultural Research(ICAR),New Delhithe Director,ICAR-National Rice Research Institute,Cuttack.
文摘Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,Sub1 and Dro1(Δbp:10 Mb),as well as Sub1 and TPP7(Δbp:6 Mb)were identified to exhibit long-range linkage disequilibrium(LRLD).Meta-QTL analysis further revealed that Sub1 and TPP7 co-segregated for tolerance to submergence at the germination and seedling stages.Based on this,we hypothesized that LRLD might influence plant responses to consecutive stresses.To test this hypothesis,we developed a structured recombinant inbred line population from a cross between Bhalum 2 and Nagina 22,with alleles(Sub1 and TPP7)in linkage equilibrium.Mendelian randomization analysis validated that the parental alleles,rather than the recombinant alleles of Sub1 and TPP7,significantly influenced 13 out of 41 traits under consecutive stress conditions.Additionally,16 minor additive effect QTLs were detected between the genomic regions,spanning Sub1 and TPP7 for various traits.A single allele difference between these genomic regions enhanced crown root number,root dry weight,and specific root area by 11.45%,15.69%,and 33.15%,respectively,under flooded germination conditions.Candidate gene analysis identified WAK79 and MRLK59 as regulators of stress responses during flooded germination,recovery,and subsequent water deficit conditions.These findings highlight the critical role of parental allele combinations and genomic regions between Sub1 and TPP7 in regulating the stress responses under consecutive stresses.Favourable haplotypes derived from these alleles can be utilized to improve stress resilience in direct-seeded rice.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFF1000500)the National Natural Science Foundation of China(Grant Nos.32372099,32172080,and 32188102)the Innovation Program of the Chinese Academy of Agricultural Sciences,China(Grant No.CAAS-CSCB-202402).
文摘Sucrose transporters(SUTs)contain multiple transmembrane domains that mediate sucrose transport and provide energy for plant growth and development.However,the role of OsSUTs in regulating rice quality and grain yield remains unclear.In this study,we identified five rice SUT genes(OsSUT1-OsSUT5)and examined their molecular characteristics and biological functions.OsSUT1,OsSUT2,and OsSUT4 were predominantly expressed in stems,while OsSUT3 and OsSUT5 showed higher expression in panicles.OsSUT1 and OsSUT4 are located on the plasma membrane,whereas OsSUT2,OsSUT3,and OsSUT5 are localized to the tonoplast.
基金supported by the National Natural Science Foundation of China(32070642 and 31371222 to Dr.Xiaoxue Wang)the National Key Research and Development Program from the Ministry of Science and Technology of China(2016YFD0100406 and 2017YFD0300107 to Dr.Xiaoxue Wang)the Science and Technology Department of Liaoning province(2022JH6/100100039 to Dr.Xiaoxue Wang)。
文摘The leaf is a major organ for photosynthesis,and its shape plays an important role in plant development and yield determination in rice(Oryza sativa L.).In this study,an adaxial curled leaf mutant,termed curly leaf 1-1(cul1-1),was obtained by chemical mutagenesis.The leaf rolling index of the cul1-1 mutant was higher than that of the wild-type,which was caused by the abnormal development of bulliform cells(BCs).We cloned the CUL1 gene by map-based cloning.A nonsense mutation was present in the cul1-1 mutant,converting a tryptophan codon into a stop codon.The CUL1 gene encodes a chromodomain,helicase/ATPase and DNA-binding domain containing protein.Genes related to leaf rolling and BC development,such as ADL1,REL1 and ROC5,were activated by the cul1-1 mutation.The trimethylation of lysine 27 in histone 3(H3K27me3),but not H3K4me3,at the ADL1,REL1 and ROC5 loci,was reduced in the cul1-1 mutant.High-throughput mRNA sequencing indicated that the cul1-1 mutation caused genome-wide differential gene expression.The differentially expressed genes were classified into a few gene ontology terms and Kyoto encyclopedia of genes and genomes pathways.In the natural population,22 missense genomic variations in the CUL1 locus were identified,which composed of 7 haplotypes.A haplotype network was also built with haplotype II as the ancestor.The findings revealed that CUL1 is essential for normal leaf development and regulates this process by inhibiting the expression of genes involved in leaf rolling and BC development.
