Pentatricopeptide repeat(PPR)proteins are a large group of eukaryote-specific RNA-binding proteins that play pivotal roles in plant organelle gene expression.Here,we report the function of PPR21 in mitochondrial intro...Pentatricopeptide repeat(PPR)proteins are a large group of eukaryote-specific RNA-binding proteins that play pivotal roles in plant organelle gene expression.Here,we report the function of PPR21 in mitochondrial intron splicing and its role in maize kernel development.PPR21 is a typical P-type PPR protein targeted to mitochondria.The ppr21 mutants are arrested in embryogenesis and endosperm development,leading to embryo lethality.Null mutations of PPR21 reduce the splicing efficiency of nad2 intron 1,2,and 4 and impair the assembly and activity of mitochondrial complex I.Previous studies show that the P-type PPR protein EMP12 is required for the splicing of identical introns.However,our protein interaction analyses reveal that PPR21 does not interact with EMP12.Instead,both PPR21 and EMP12 interact with the small MutS-related(SMR)domain-containing PPR protein 1(PPR-SMR1)and the short P-type PPR protein 2(SPR2).PPR-SMR1 interacts with SPR2,and both proteins are required for the splicing of many introns in mitochondria,including nad2 intron 1,2,and 4.These results suggest that a PPR21-(PPR-SMR1/SPR2)-EMP12 complex is involved in the splicing of nad2 introns in maize mitochondria.展开更多
The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use e...The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use efficiency and enhancing crop stress resistance.Nevertheless,the precise interaction between soil warming(SW)and SN remains unclear.In order to ascertain the impact of SW on maize growth and whether SN can improve the tolerance of maize to SW,a two-year field experiment was conducted(2022-2023).The aim was to examine the influence of two SW ranges(MT,warming 1.40℃;HT,warming 2.75℃)and two nitrogen application methods(N1,one-time basal application of nitrogen fertilizer;N2,one third of base nitrogen fertilizer+two thirds of jointing stage supplemental nitrogen fertilizer)on maize root growth,photosynthetic characteristics,nitrogen use efficiency,and yield.The results demonstrated that SW impeded root growth and precipitated the premature aging of maize leaves following anthesis,particularly in the HT,which led to a notable reduction in maize yield.In comparison to N1,SN has been shown to increase root length density by 8.54%,root bleeding rate by 8.57%,and enhance root distribution ratio in the middle soil layers(20-60 cm).The interaction between SW and SN had a notable impact on maize growth and yield.The SN improved the absorption and utilization efficiency of nitrogen by promoting root development and downward canopy growth,thus improving the tolerance of maize to SW at the later stage of growth.In particular,the N2HT resulted in a 14.51%increase in the photosynthetic rate,a 18.58%increase in nitrogen absorption efficiency,and a 18.32%increase in maize yield compared with N1HT.It can be posited that the SN represents a viable nitrogen management measure with the potential to enhance maize tolerance to soil high-temperature stress.展开更多
Maize(Zea mays L.)is a monoecious grass species with separate male and female inflorescences which form the tassel and ear,respectively.The mature ear inflorescences usually bear hundreds of grains,so they directly in...Maize(Zea mays L.)is a monoecious grass species with separate male and female inflorescences which form the tassel and ear,respectively.The mature ear inflorescences usually bear hundreds of grains,so they directly influence maize grain production and yield.Here,we isolated a recessive maize mutant,tasselseed2016(ts2016),which exhibits pleiotropic inflorescence defects and reduced grain yield.These defects include the loss of determinacy and identity in meristems and floral organs,as well as a lack of the lower floret abortion in maize ear,and a smaller grain size.Using map-based cloning and allelic testing,we identified and confirmed the microRNA gene MIR172e as the target gene controlling these related traits.Furthermore,our evidence uncovered a new potential miR172e/ETHYLENE RESPONSIVE ELEMENT BINDING197(EREB197)regulatory module which controls lower floret abortion in maize ear.Transcriptome analysis revealed that the mutation of MIR172e represses multiple biological processes,particularly the flower development and hormone-related pathways in maize ear.We also found that a mutation in the DNA sequence of MIR172e affects RNA transcription,resulting in elongation blockage at the mutant site.Our results reveal the function and molecular mechanism of MIR172e in maize inflorescences and grain yield,and this study deepens our knowledge of maize inflorescence development.展开更多
Increasing plant density is an effective strategy for enhancing crop yield per unit land area.A key architectural trait for crops adapting to high planting density is a smaller leaf angle(LA).Previous studies have dem...Increasing plant density is an effective strategy for enhancing crop yield per unit land area.A key architectural trait for crops adapting to high planting density is a smaller leaf angle(LA).Previous studies have demonstrated that LG1,a SQUAMOSA BINDING PROTEIN(SBP)transcription factor,plays a critical role in LA establishment.However,the molecular mechanisms underlying the regulation of LG1 on LA formation remain largely unclear.In this study,we conduct comparative RNA-seq analysis of the preligule band(PLB)region of wild type and lg1 mutant leaves.Gene Ontology(GO)term enrichment analysis reveals enrichment of phytohormone pathways and transcription factors,including three auxin transporter genes ZmPIN1a,ZmPIN1b,and ZmPIN1c.Further molecular experiments demonstrate that LG1 can directly bind to the promoter region of these auxin transporter genes and activate their transcription.We also show that double and triple mutants of these ZmPINs genes exhibit varying degrees of auricle size reduction and thus decreased LA.On the contrary,overexpression of ZmPIN1a causes larger auricle and LA.Taken together,our findings establish a functional link between LG1 and auxin transport in regulating PLB formation and provide valuable targets for genetic improvement of LA for breeding high-density tolerant maize cultivars.展开更多
With the aim of adapting agricultural practices to climate warming,this study projected sowing dates for summer maize in the 2030s(2031–2040)across the Huanghuaihai Plain by analyzing key photo-thermal variables deri...With the aim of adapting agricultural practices to climate warming,this study projected sowing dates for summer maize in the 2030s(2031–2040)across the Huanghuaihai Plain by analyzing key photo-thermal variables derived from field experiments and projected future climate data under Shared Socioeconomic Pathway 2–4.5 within a restricted planting season.Results showed that growing degree days(GDD)during the active dry matter accumulation period(AP),killing degree days(KDD)during AP,and GDD during the late dry matter accumulation period(LP)explained most yield variation and were used for determining suitable sowing windows.Thresholds of them were 571°C d,21°C d and 411°C d,respectively.In the 2030s,postponing sowing dates and shifting planting regions northward resulted in gradual declines in KDD during AP and GDD during LP.The proportion of regions limited by KDD and GDD changed from 66%to 0%and from 3%to 100%when sowing dates were postponed from June 1 to July 15.Suitable sowing dates for maize were determined as follows:June 25 to July 10 in regions south of 34°N,June 5 to June 30 between 34°N and 39°N,and before June 20 in regions north of 39°N.展开更多
The female inflorescence,or ear,of maize develops no branch meristem(BM),which differs from the male inforescence,or tassel.While the mutations of some well documented genes,such as fea2/3/4 and ramosa1/2/3,can cause ...The female inflorescence,or ear,of maize develops no branch meristem(BM),which differs from the male inforescence,or tassel.While the mutations of some well documented genes,such as fea2/3/4 and ramosa1/2/3,can cause the branched architecture of ears in maize,such mutations also change the normal phenotypic performance of the tassels.In the present study,a natural maize mutant with branched ears,named branched ear1(be1),was characterized.be1 shows several branched ears at the base of the central ear with unchanged architecture of the tassels.Besides,both the branched and central ears of be1 possess regularly arranged kerels.The phenotypic characteristics of be1 differ completely from those reported mutants of fasciated ears or RAMOSA-like ears in maize.An SEM survey at the very early development stage showed that meristems with three protrusions,similar to the BM in tassels,were present during the development of the branched ears in be1.Gene mapping and sequence alignment suggested that TEOSINTE BRANCHED1(TB1)was the candidate gene of BE1.Further verification showed that a be1-specific 31 bp deletion at the downstream of BE1 led to statistically reduced expression of this gene in the immature ear,which serves as the potential causal reason for the branched ears of be1.CRISPR/Cas9-based gene editing downstream of TB1 complemented the phenotypic architecture of branched ears,suggesting that TB1 was the target of BE1,and it was named as Zm TB1be1.The results of the present study implied a novel function of TB1 in female inforescence development,rather than shaping the plant architecture in maize.Meanwhile,further functional dissection of ZmTB1be1might shed new light on TB1,the most famous domestication related gene in maize.展开更多
Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we e...Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we employed two recombinant inbred line(RIL)populations with the common resistant parental line CML304 to identify FER-resistance loci.Initial QTL analysis identified 23 FER-resistance QTL,each explaining 5.21%-30.51%of the total phenotypic variation.Notably,one major QTL,qRfv2,on chromosome 2 was repeatedly detected,accounting for 11.92%-30.51%of the total phenotypic variation.qRfv2 was fine mapped to an interval of 1.01 Mb,flanked by the markers IDP8 and IDP10.qRfv2 is a semidominant resistance gene that could reduce the disease severity index(DSI)by 12.4%-20%,suggesting its potential for enhancing FER resistance in maize.Transcriptome analysis showed that 22 of the 28 annotated functional genes in the qRfv2 region displayed differential expression between parental lines in response to FER.One of the candidate genes,ZmLOX6,was validated to presumably provide a positive effect on FER resistance.Our study provides a basis for the potential cloning and application of FER resistance genes in maize breeding.展开更多
[Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu...[Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 as experimental materials,we preliminarily measured the dynamic changes of dry matter accumulation and moisture content with the days after pollination lasted,and investigated the effect of moisture content in kernels on mechanical harvesting of Zhengdan 958 and Liyu 16.[Results] During summer growing season,Zhengdan 958 and Liyu 16 became physiologically mature and suitable for harvesting at about 51 days after pollination,Xianyu 335 and Hongda 8 required 58 days to become physiologically mature and suitable for harvesting after pollination.At physiologically mature stage,the moisture contents in kernels of Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 were respectively 33.74%,28.86%,32.05% and 35.24%,respectively.Adopting mechanical harvesting at physiologically mature stage,the kernel loss rate of Zhengdan 958 and Liyu 16 was consistent with the range of mechanical operation index（kernel loss rate of 0.84%≤2%）,while the percentage of broken kernels did not accord with the range of mechanical operation index（kernel crashing rate of 10.12%≧1%）.The results indicate that Zhengdan 958 and Liyu 16 are not suitable for mechanical harvesting using full feeding combine havester.[Conclusion] This study provided theoretical basis for improving the maize harvest index under delayed harvesting.展开更多
This study examines the role of maize in food security and economic stability,focusing on its response to climate change and strategies to enhance resilience.Using a qualitative descriptive research methodology,the st...This study examines the role of maize in food security and economic stability,focusing on its response to climate change and strategies to enhance resilience.Using a qualitative descriptive research methodology,the study analyzes the impact of climate change on global maize production and proposes innovative strategies for sustainability and food security.The agricultural environment is vulnerable to heavy metal toxicity,which is linked to the relationship between soil health and climate change.From 1850 to 2020,the Earth’s temperature increased by 1.1℃,with projections indicating continued warming.This trend has significant economic implications,particularly in developing countries where agriculture employs 69%of the population.Heat waves and droughts represent abiotic stresses faced by maize.Research suggests that high greenhouse gas emissions could lead to a 24%reduction in maize yield by 2030.The study highlights the need to focus on breeding and phenotyping technologies to develop heat-and drought-tolerant maize varieties that use water efficiently.Additionally,strategies such as genomic editing,transcriptome analysis,and maize quality mapping are crucial to addressing these challenges.Developing insect-resistant maize is another objective.This study emphasizes the necessity of ongoing research to improve agricultural productivity and ensure food security,especially in light of global population growth.It also advocates for new regulations to reduce greenhouse gas emissions,which contribute to global warming.展开更多
Heat stress,a major challenge in modern agriculture due to global warming,significantly reduces crop productivity.To mitigate its adverse effects on maize yield,it is crucial to understand the mechanisms by which heat...Heat stress,a major challenge in modern agriculture due to global warming,significantly reduces crop productivity.To mitigate its adverse effects on maize yield,it is crucial to understand the mechanisms by which heat stress impacts reproductive development.This study investigated the impact of heat stress during the 12th leaf(V12)stage,where silk development begins on grain yield formation,using heat-sensitive and heat-tolerant cultivars.Compared to pollen,silks were found to be more vulnerable to heat stress.Heat stress disrupted hormone balance and inhibited hormone signaling transduction pathways in silks,delaying silk emergence from bracts and reducing fertilization and grain yield.The heat-tolerant cultivar maintained silk growth by activating more response pathways,displaying faster hormone responses,and up-regulating hormones.Taken together,we propose that hormones play an essential role in silk development and later fertilization process.展开更多
Mitochondria are semi-autonomous organelles present in eukaryotic cells,containing their own genome and transcriptional machinery.However,their functions are intricately linked to proteins encoded by the nuclear genom...Mitochondria are semi-autonomous organelles present in eukaryotic cells,containing their own genome and transcriptional machinery.However,their functions are intricately linked to proteins encoded by the nuclear genome.Mitochondrial transcription termination factors(mTERFs)are nucleic acid-binding proteins involved in RNA splicing and transcription termination within plant mitochondria and chloroplasts.Despite their recognized importance,the specific roles of mTERF proteins in maize remain largely unexplored.Here,we clone and functionally characterize the maize mTERF18 gene.Our findings reveal that mTERF18 mutations lead to severely undifferentiated embryos,resulting in abortive phenotypes.Early kernel exhibits abnormal basal endosperm transfer layer and a significant reduction in both starch and protein accumulation in mterf18.We identify the mTERF18 gene through mapping-based cloning and validate this gene through allelic tests.mTERF18 is widely expressed across various maize tissues and encodes a highly conserved mitochondrial protein.Transcriptome data reveal that mTERF18 mutations disrupt transcriptional termination of the nad6 gene,leading to undetectable levels of Nad6 protein and reduced complex I assembly and activity.Furthermore,transmission electron microscopy observation of mterf18 endosperm uncover severe mitochondrial defects.Collectively,these findings highlight the critical role of mTERF18 in mitochondrial gene transcription termination and its pivotal impact on maize kernel development.展开更多
Maize serves as a crucial cereal crop globally,yet the escalating frequency of drought stress during the reproductive phase poses a significant threat to grain yield by causing an irreversible loss in kernel number.En...Maize serves as a crucial cereal crop globally,yet the escalating frequency of drought stress during the reproductive phase poses a significant threat to grain yield by causing an irreversible loss in kernel number.Enhancing reproductive drought tolerance in maize requires elucidating the physiological mechanisms underlying its response to drought stress,which can then be incorporated into the development of new maize varieties through breeding programs.Additionally,innovative cultivation practices must be devised to complement these genetic improvements.In this review,the timing,duration,and severity of drought stress during the reproductive stage and their effects on maize kernel set are assessed,providing a basis for constructing a framework that links kernel setting to drought stress.Based on this framework,reproductive drought tolerance from tasseling through post-fertilization kernel establishment is subsequently examined.Evidence indicates that drought-induced fertilization failure is primarily due to delayed pollination resulting from slower silk elongation,which is caused by the loss of cell turgor and reduced carbon supply.Meanwhile,kernel abortion after fertilization is mainly triggered by carbohydrate starvation,increased ethylene emission,and the accumulation of abscisic acid(ABA).Therefore,sugar metabolism,hydraulic status,and hormone signaling collectively regulate maize's kernel setting tolerance to drought stress in a synergistic manner.Several novel gene candidates with potential for conferring drought tolerance in maize have been identified,offering promising targets for genetic improvement through genome editing combined with targeted cultivation practices to enhance maize drought tolerance and ensure stable grain yield in future crops.展开更多
Efficient and accurate identification of candidate causal genes within quantitative trait loci(QTL)is a significant challenge in genetic research.Conventional linkage analysis methods often require substantial time an...Efficient and accurate identification of candidate causal genes within quantitative trait loci(QTL)is a significant challenge in genetic research.Conventional linkage analysis methods often require substantial time and resources to identify causal genes.This paper proposes a QTG-LGBM method for prioritizing causal genes in maize based on the Light GBM algorithm.QTG-LGBM dynamically adjusts gene weights and sample proportions during training to mitigate the effects of class imbalance.The method prevents overfitting in datasets with small samples by introducing a regularization term.Experimental results on maize traits,including plant height(PH),flowering time(FT),and tassel branch number(TBN),demonstrated that QTG-LGBM outperforms the commonly used methods QTG-Finder,GBDT,XGBoost,Bernoulli NB,SVM,CNN,and ensemble learning.We validated the generalization of QTG-LGBM using Arabidopsis,rice,Setaria,and sorghum.We also applied QTG-LGBM using reported QTL that affect traits of maize PH,FT and TBN,and FT in Arabidopsis,rice,and sorghum,as well as known causal genes within the QTL.When examining the top 20%of ranked genes,QTG-LGBM demonstrated a significantly higher recall rate of causal genes compared to random selection methods.We identified key gene features affecting phenotypes through feature importance analysis.QTG-LGBM is available at http://www.deepcba.com/QTG-LGBM.展开更多
[Objective]The aim was to optimize SSR reaction system applied in the identification of authenticity of maize variety.[Method]The technical parameters of SSR including PCR reaction system,annealing temperature and ele...[Objective]The aim was to optimize SSR reaction system applied in the identification of authenticity of maize variety.[Method]The technical parameters of SSR including PCR reaction system,annealing temperature and electrophoresis time were optimized to identify 10 major maize varieties in Liaoning Province.[Result]The optimum PCR reaction system was：14.60 μl sterile ultrapure water,2.00 μl 10 × Buffer（Mg2＋）,1.20 μl dNTPs,0.20 μl Taq enzyme,0.50 μl each of the forward and reverse primers and1.00 μl DNA stock solution.Annealing temperature and electrophoresis time could greatly influence the results of PCR amplification.The optimal annealing temperature and electrophoresis time required for the ideal electrophoresis bands under the same conditions were different when different primers were used.[Conclusion]The system was feasible to be applied in rapid identification of authenticity of hybrid maize varieties.展开更多
In this study, six CIMMYT maize inbred lines and five representative do- mestic maize inbred lines were used as parental lines. By using incomplete diallel cross design, 30 hybrid combinations were developed to analyz...In this study, six CIMMYT maize inbred lines and five representative do- mestic maize inbred lines were used as parental lines. By using incomplete diallel cross design, 30 hybrid combinations were developed to analyze the general com- bining ability （GCA）, specific combining ability （SCA） and total combining ability （TCA） of seven panicle traits in six CIMMYT maize inbred lines. The results showed that CIMBL98 and GEMS13 were excellent inbred lines with good compre- hensive performance; CIMBL98 × 340 and GEMS13×Chang 7-2 were superior combinations.展开更多
基金supported by the National Natural Science Foundation of China(32072126 and 32230075)the Shandong Provincial Natural Science Foundation(ZR2019MC005).
文摘Pentatricopeptide repeat(PPR)proteins are a large group of eukaryote-specific RNA-binding proteins that play pivotal roles in plant organelle gene expression.Here,we report the function of PPR21 in mitochondrial intron splicing and its role in maize kernel development.PPR21 is a typical P-type PPR protein targeted to mitochondria.The ppr21 mutants are arrested in embryogenesis and endosperm development,leading to embryo lethality.Null mutations of PPR21 reduce the splicing efficiency of nad2 intron 1,2,and 4 and impair the assembly and activity of mitochondrial complex I.Previous studies show that the P-type PPR protein EMP12 is required for the splicing of identical introns.However,our protein interaction analyses reveal that PPR21 does not interact with EMP12.Instead,both PPR21 and EMP12 interact with the small MutS-related(SMR)domain-containing PPR protein 1(PPR-SMR1)and the short P-type PPR protein 2(SPR2).PPR-SMR1 interacts with SPR2,and both proteins are required for the splicing of many introns in mitochondria,including nad2 intron 1,2,and 4.These results suggest that a PPR21-(PPR-SMR1/SPR2)-EMP12 complex is involved in the splicing of nad2 introns in maize mitochondria.
基金supported by the Natural Science Fund of China(31771724)the Key Research and Development Project of Shaanxi Province(2024NC-ZDCYL-01-10).
文摘The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use efficiency and enhancing crop stress resistance.Nevertheless,the precise interaction between soil warming(SW)and SN remains unclear.In order to ascertain the impact of SW on maize growth and whether SN can improve the tolerance of maize to SW,a two-year field experiment was conducted(2022-2023).The aim was to examine the influence of two SW ranges(MT,warming 1.40℃;HT,warming 2.75℃)and two nitrogen application methods(N1,one-time basal application of nitrogen fertilizer;N2,one third of base nitrogen fertilizer+two thirds of jointing stage supplemental nitrogen fertilizer)on maize root growth,photosynthetic characteristics,nitrogen use efficiency,and yield.The results demonstrated that SW impeded root growth and precipitated the premature aging of maize leaves following anthesis,particularly in the HT,which led to a notable reduction in maize yield.In comparison to N1,SN has been shown to increase root length density by 8.54%,root bleeding rate by 8.57%,and enhance root distribution ratio in the middle soil layers(20-60 cm).The interaction between SW and SN had a notable impact on maize growth and yield.The SN improved the absorption and utilization efficiency of nitrogen by promoting root development and downward canopy growth,thus improving the tolerance of maize to SW at the later stage of growth.In particular,the N2HT resulted in a 14.51%increase in the photosynthetic rate,a 18.58%increase in nitrogen absorption efficiency,and a 18.32%increase in maize yield compared with N1HT.It can be posited that the SN represents a viable nitrogen management measure with the potential to enhance maize tolerance to soil high-temperature stress.
基金supported by the Natural Science Foundation of Henan Province,China(232300421260)the Tackling Key Problems in Science and Technology of Henan Province,China(222102110465,to LZ and 232102111097,to YS)the Open Project Program(SKL-KF202214)。
文摘Maize(Zea mays L.)is a monoecious grass species with separate male and female inflorescences which form the tassel and ear,respectively.The mature ear inflorescences usually bear hundreds of grains,so they directly influence maize grain production and yield.Here,we isolated a recessive maize mutant,tasselseed2016(ts2016),which exhibits pleiotropic inflorescence defects and reduced grain yield.These defects include the loss of determinacy and identity in meristems and floral organs,as well as a lack of the lower floret abortion in maize ear,and a smaller grain size.Using map-based cloning and allelic testing,we identified and confirmed the microRNA gene MIR172e as the target gene controlling these related traits.Furthermore,our evidence uncovered a new potential miR172e/ETHYLENE RESPONSIVE ELEMENT BINDING197(EREB197)regulatory module which controls lower floret abortion in maize ear.Transcriptome analysis revealed that the mutation of MIR172e represses multiple biological processes,particularly the flower development and hormone-related pathways in maize ear.We also found that a mutation in the DNA sequence of MIR172e affects RNA transcription,resulting in elongation blockage at the mutant site.Our results reveal the function and molecular mechanism of MIR172e in maize inflorescences and grain yield,and this study deepens our knowledge of maize inflorescence development.
基金supported by the National Key Research and Development Program of China(2021YFF1000301)the National Natural Science Foundation of China(32472179,32130077,32201835)+2 种基金the Natural Science Foundation of Hebei Province(C2022407068)the Natural Science Foundation of Guangdong Province(2024A1515030237,2022A1515011002)the Hainan Yazhou Bay Seed Lab(B21HJ8101).
文摘Increasing plant density is an effective strategy for enhancing crop yield per unit land area.A key architectural trait for crops adapting to high planting density is a smaller leaf angle(LA).Previous studies have demonstrated that LG1,a SQUAMOSA BINDING PROTEIN(SBP)transcription factor,plays a critical role in LA establishment.However,the molecular mechanisms underlying the regulation of LG1 on LA formation remain largely unclear.In this study,we conduct comparative RNA-seq analysis of the preligule band(PLB)region of wild type and lg1 mutant leaves.Gene Ontology(GO)term enrichment analysis reveals enrichment of phytohormone pathways and transcription factors,including three auxin transporter genes ZmPIN1a,ZmPIN1b,and ZmPIN1c.Further molecular experiments demonstrate that LG1 can directly bind to the promoter region of these auxin transporter genes and activate their transcription.We also show that double and triple mutants of these ZmPINs genes exhibit varying degrees of auricle size reduction and thus decreased LA.On the contrary,overexpression of ZmPIN1a causes larger auricle and LA.Taken together,our findings establish a functional link between LG1 and auxin transport in regulating PLB formation and provide valuable targets for genetic improvement of LA for breeding high-density tolerant maize cultivars.
基金supported by National Natural Science Foundation of China(32172115)National Modern Agriculture Industry Technology System(CARS-02-21).
文摘With the aim of adapting agricultural practices to climate warming,this study projected sowing dates for summer maize in the 2030s(2031–2040)across the Huanghuaihai Plain by analyzing key photo-thermal variables derived from field experiments and projected future climate data under Shared Socioeconomic Pathway 2–4.5 within a restricted planting season.Results showed that growing degree days(GDD)during the active dry matter accumulation period(AP),killing degree days(KDD)during AP,and GDD during the late dry matter accumulation period(LP)explained most yield variation and were used for determining suitable sowing windows.Thresholds of them were 571°C d,21°C d and 411°C d,respectively.In the 2030s,postponing sowing dates and shifting planting regions northward resulted in gradual declines in KDD during AP and GDD during LP.The proportion of regions limited by KDD and GDD changed from 66%to 0%and from 3%to 100%when sowing dates were postponed from June 1 to July 15.Suitable sowing dates for maize were determined as follows:June 25 to July 10 in regions south of 34°N,June 5 to June 30 between 34°N and 39°N,and before June 20 in regions north of 39°N.
基金supported by the Special Key Project for Technological Innovation and Application Development in Chongqing,China(CSTB2022TIAD-KPX0011)the Special Fund for Youth Team of the Southwest Universities,China(SWU-XJPY202306)+1 种基金the Natural Science Foundation of Chongqing,China(cstc2021jcyj-msxmX0583)the Fundamental Research Funds for the Central Universities of Southwest University,China(S202210635326)。
文摘The female inflorescence,or ear,of maize develops no branch meristem(BM),which differs from the male inforescence,or tassel.While the mutations of some well documented genes,such as fea2/3/4 and ramosa1/2/3,can cause the branched architecture of ears in maize,such mutations also change the normal phenotypic performance of the tassels.In the present study,a natural maize mutant with branched ears,named branched ear1(be1),was characterized.be1 shows several branched ears at the base of the central ear with unchanged architecture of the tassels.Besides,both the branched and central ears of be1 possess regularly arranged kerels.The phenotypic characteristics of be1 differ completely from those reported mutants of fasciated ears or RAMOSA-like ears in maize.An SEM survey at the very early development stage showed that meristems with three protrusions,similar to the BM in tassels,were present during the development of the branched ears in be1.Gene mapping and sequence alignment suggested that TEOSINTE BRANCHED1(TB1)was the candidate gene of BE1.Further verification showed that a be1-specific 31 bp deletion at the downstream of BE1 led to statistically reduced expression of this gene in the immature ear,which serves as the potential causal reason for the branched ears of be1.CRISPR/Cas9-based gene editing downstream of TB1 complemented the phenotypic architecture of branched ears,suggesting that TB1 was the target of BE1,and it was named as Zm TB1be1.The results of the present study implied a novel function of TB1 in female inforescence development,rather than shaping the plant architecture in maize.Meanwhile,further functional dissection of ZmTB1be1might shed new light on TB1,the most famous domestication related gene in maize.
基金financially funded by the National Natural Science Foundation of China(U2004205)the China Agricultural University-Syngenta Project.
文摘Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we employed two recombinant inbred line(RIL)populations with the common resistant parental line CML304 to identify FER-resistance loci.Initial QTL analysis identified 23 FER-resistance QTL,each explaining 5.21%-30.51%of the total phenotypic variation.Notably,one major QTL,qRfv2,on chromosome 2 was repeatedly detected,accounting for 11.92%-30.51%of the total phenotypic variation.qRfv2 was fine mapped to an interval of 1.01 Mb,flanked by the markers IDP8 and IDP10.qRfv2 is a semidominant resistance gene that could reduce the disease severity index(DSI)by 12.4%-20%,suggesting its potential for enhancing FER resistance in maize.Transcriptome analysis showed that 22 of the 28 annotated functional genes in the qRfv2 region displayed differential expression between parental lines in response to FER.One of the candidate genes,ZmLOX6,was validated to presumably provide a positive effect on FER resistance.Our study provides a basis for the potential cloning and application of FER resistance genes in maize breeding.
基金Supported by Supporting Program for Sci & Tech Research of China(2009BADA6B01)Natural Science Foundation of Anhui Province(090411017)~~
文摘[Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 as experimental materials,we preliminarily measured the dynamic changes of dry matter accumulation and moisture content with the days after pollination lasted,and investigated the effect of moisture content in kernels on mechanical harvesting of Zhengdan 958 and Liyu 16.[Results] During summer growing season,Zhengdan 958 and Liyu 16 became physiologically mature and suitable for harvesting at about 51 days after pollination,Xianyu 335 and Hongda 8 required 58 days to become physiologically mature and suitable for harvesting after pollination.At physiologically mature stage,the moisture contents in kernels of Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 were respectively 33.74%,28.86%,32.05% and 35.24%,respectively.Adopting mechanical harvesting at physiologically mature stage,the kernel loss rate of Zhengdan 958 and Liyu 16 was consistent with the range of mechanical operation index（kernel loss rate of 0.84%≤2%）,while the percentage of broken kernels did not accord with the range of mechanical operation index（kernel crashing rate of 10.12%≧1%）.The results indicate that Zhengdan 958 and Liyu 16 are not suitable for mechanical harvesting using full feeding combine havester.[Conclusion] This study provided theoretical basis for improving the maize harvest index under delayed harvesting.
文摘This study examines the role of maize in food security and economic stability,focusing on its response to climate change and strategies to enhance resilience.Using a qualitative descriptive research methodology,the study analyzes the impact of climate change on global maize production and proposes innovative strategies for sustainability and food security.The agricultural environment is vulnerable to heavy metal toxicity,which is linked to the relationship between soil health and climate change.From 1850 to 2020,the Earth’s temperature increased by 1.1℃,with projections indicating continued warming.This trend has significant economic implications,particularly in developing countries where agriculture employs 69%of the population.Heat waves and droughts represent abiotic stresses faced by maize.Research suggests that high greenhouse gas emissions could lead to a 24%reduction in maize yield by 2030.The study highlights the need to focus on breeding and phenotyping technologies to develop heat-and drought-tolerant maize varieties that use water efficiently.Additionally,strategies such as genomic editing,transcriptome analysis,and maize quality mapping are crucial to addressing these challenges.Developing insect-resistant maize is another objective.This study emphasizes the necessity of ongoing research to improve agricultural productivity and ensure food security,especially in light of global population growth.It also advocates for new regulations to reduce greenhouse gas emissions,which contribute to global warming.
基金supported by the National Natural Science Foundation of China(32071959)the National Key Research and Development Program of China(2023YFD2303304)+1 种基金the Key Research and Development Program of Shandong Province(LJNY202103)the Shandong Province Key Agricultural Project for Application Technology Innovation(SDAIT02-08)to Peng Liu.
文摘Heat stress,a major challenge in modern agriculture due to global warming,significantly reduces crop productivity.To mitigate its adverse effects on maize yield,it is crucial to understand the mechanisms by which heat stress impacts reproductive development.This study investigated the impact of heat stress during the 12th leaf(V12)stage,where silk development begins on grain yield formation,using heat-sensitive and heat-tolerant cultivars.Compared to pollen,silks were found to be more vulnerable to heat stress.Heat stress disrupted hormone balance and inhibited hormone signaling transduction pathways in silks,delaying silk emergence from bracts and reducing fertilization and grain yield.The heat-tolerant cultivar maintained silk growth by activating more response pathways,displaying faster hormone responses,and up-regulating hormones.Taken together,we propose that hormones play an essential role in silk development and later fertilization process.
基金supported by the National Key Research and Development Program of China(2021YFF1000304)the National Natural Science Foundation of China(32222060)Anhui Agricultural University(RC422404)to J.Y.
文摘Mitochondria are semi-autonomous organelles present in eukaryotic cells,containing their own genome and transcriptional machinery.However,their functions are intricately linked to proteins encoded by the nuclear genome.Mitochondrial transcription termination factors(mTERFs)are nucleic acid-binding proteins involved in RNA splicing and transcription termination within plant mitochondria and chloroplasts.Despite their recognized importance,the specific roles of mTERF proteins in maize remain largely unexplored.Here,we clone and functionally characterize the maize mTERF18 gene.Our findings reveal that mTERF18 mutations lead to severely undifferentiated embryos,resulting in abortive phenotypes.Early kernel exhibits abnormal basal endosperm transfer layer and a significant reduction in both starch and protein accumulation in mterf18.We identify the mTERF18 gene through mapping-based cloning and validate this gene through allelic tests.mTERF18 is widely expressed across various maize tissues and encodes a highly conserved mitochondrial protein.Transcriptome data reveal that mTERF18 mutations disrupt transcriptional termination of the nad6 gene,leading to undetectable levels of Nad6 protein and reduced complex I assembly and activity.Furthermore,transmission electron microscopy observation of mterf18 endosperm uncover severe mitochondrial defects.Collectively,these findings highlight the critical role of mTERF18 in mitochondrial gene transcription termination and its pivotal impact on maize kernel development.
基金financially supported by the Natural Key Research and Development Program of China(2023YFD2301500)。
文摘Maize serves as a crucial cereal crop globally,yet the escalating frequency of drought stress during the reproductive phase poses a significant threat to grain yield by causing an irreversible loss in kernel number.Enhancing reproductive drought tolerance in maize requires elucidating the physiological mechanisms underlying its response to drought stress,which can then be incorporated into the development of new maize varieties through breeding programs.Additionally,innovative cultivation practices must be devised to complement these genetic improvements.In this review,the timing,duration,and severity of drought stress during the reproductive stage and their effects on maize kernel set are assessed,providing a basis for constructing a framework that links kernel setting to drought stress.Based on this framework,reproductive drought tolerance from tasseling through post-fertilization kernel establishment is subsequently examined.Evidence indicates that drought-induced fertilization failure is primarily due to delayed pollination resulting from slower silk elongation,which is caused by the loss of cell turgor and reduced carbon supply.Meanwhile,kernel abortion after fertilization is mainly triggered by carbohydrate starvation,increased ethylene emission,and the accumulation of abscisic acid(ABA).Therefore,sugar metabolism,hydraulic status,and hormone signaling collectively regulate maize's kernel setting tolerance to drought stress in a synergistic manner.Several novel gene candidates with potential for conferring drought tolerance in maize have been identified,offering promising targets for genetic improvement through genome editing combined with targeted cultivation practices to enhance maize drought tolerance and ensure stable grain yield in future crops.
基金supported by the Biological Breeding-Major Projects(2023ZD04067)Hubei Provincial Natural Science Foundation of China(2023AFB832)+1 种基金Guizhou Provincial Basic Research Program(Natural Science)(MS[2025]096)Major Project of Hubei Hongshan Laboratory(2022HSZD031)。
文摘Efficient and accurate identification of candidate causal genes within quantitative trait loci(QTL)is a significant challenge in genetic research.Conventional linkage analysis methods often require substantial time and resources to identify causal genes.This paper proposes a QTG-LGBM method for prioritizing causal genes in maize based on the Light GBM algorithm.QTG-LGBM dynamically adjusts gene weights and sample proportions during training to mitigate the effects of class imbalance.The method prevents overfitting in datasets with small samples by introducing a regularization term.Experimental results on maize traits,including plant height(PH),flowering time(FT),and tassel branch number(TBN),demonstrated that QTG-LGBM outperforms the commonly used methods QTG-Finder,GBDT,XGBoost,Bernoulli NB,SVM,CNN,and ensemble learning.We validated the generalization of QTG-LGBM using Arabidopsis,rice,Setaria,and sorghum.We also applied QTG-LGBM using reported QTL that affect traits of maize PH,FT and TBN,and FT in Arabidopsis,rice,and sorghum,as well as known causal genes within the QTL.When examining the top 20%of ranked genes,QTG-LGBM demonstrated a significantly higher recall rate of causal genes compared to random selection methods.We identified key gene features affecting phenotypes through feature importance analysis.QTG-LGBM is available at http://www.deepcba.com/QTG-LGBM.
文摘[Objective]The aim was to optimize SSR reaction system applied in the identification of authenticity of maize variety.[Method]The technical parameters of SSR including PCR reaction system,annealing temperature and electrophoresis time were optimized to identify 10 major maize varieties in Liaoning Province.[Result]The optimum PCR reaction system was：14.60 μl sterile ultrapure water,2.00 μl 10 × Buffer（Mg2＋）,1.20 μl dNTPs,0.20 μl Taq enzyme,0.50 μl each of the forward and reverse primers and1.00 μl DNA stock solution.Annealing temperature and electrophoresis time could greatly influence the results of PCR amplification.The optimal annealing temperature and electrophoresis time required for the ideal electrophoresis bands under the same conditions were different when different primers were used.[Conclusion]The system was feasible to be applied in rapid identification of authenticity of hybrid maize varieties.
基金Supported by 2015 Basic Research Operating Expenses Program of Chongqing Municipality‘Excavation and Appraisal of High-Se Maize Germplasm Resources’Key Project of Development and Application of Chongqing Municipality(cstc2014yykf B80014)~~
文摘In this study, six CIMMYT maize inbred lines and five representative do- mestic maize inbred lines were used as parental lines. By using incomplete diallel cross design, 30 hybrid combinations were developed to analyze the general com- bining ability （GCA）, specific combining ability （SCA） and total combining ability （TCA） of seven panicle traits in six CIMMYT maize inbred lines. The results showed that CIMBL98 and GEMS13 were excellent inbred lines with good compre- hensive performance; CIMBL98 × 340 and GEMS13×Chang 7-2 were superior combinations.
