Grain size is a crucial factor influencing both rice yield and appearance quality.In this study,we identified GL6.1 as a gene associated with rice grain size by map-based cloning.The GL6.1 encodes a protein with CC-NB...Grain size is a crucial factor influencing both rice yield and appearance quality.In this study,we identified GL6.1 as a gene associated with rice grain size by map-based cloning.The GL6.1 encodes a protein with CC-NB-LRR domain,a structural motif related to rice disease resistance.Genetic transformation experiments and the construction of gene pyramiding lines indicate that GL6.1 functions as a negative regulatory factor for rice grain length.By the analysis of SSSLs with diverse donor parents,a total of 11 single nucleotide polymorphisms(SNPs)are identified that are closely associated with the phenotype variations.A yeast one-hybrid library screening revealed that GL6.1 interacts with OsWRKY53,a transcription factor associated with rice disease resistance.Furthermore,RNA-seq assay also revealed the involvement of pathways associated with disease resistance,hinting at a multifaceted role for GL6.1 in both yield and stress tolerance traits in rice.These results indicate that the cloning and in-depth studies of GL6.1 would provide valuable insights into the interplay among high yield,superior quality,and stress tolerance,which are critical goals for rice breeding.展开更多
Wheat grain morphology,particularly grain length(GL)and width(GW),is a key determinant of yield.To improve the suboptimal grain dimensions of the local anthocyanin-rich variety Guizi 1(GZ1),we crossed it with Zhongyan...Wheat grain morphology,particularly grain length(GL)and width(GW),is a key determinant of yield.To improve the suboptimal grain dimensions of the local anthocyanin-rich variety Guizi 1(GZ1),we crossed it with Zhongyan 96-3(ZY96-3),an elite germplasm known for faster grain filling and superior grain size.A genotyping-by-sequencing(GBS)approach was applied to an F_(2)population of 110 individuals derived from GZ1×ZY96-3,resulting in the identification of 23,134 high-quality SNPs.Most of the SNPs associated with GL and GW were clustered on chromosomes 2B,3A,and 3B.QTL mapping for GL revealed two major loci,GL1 on chromosome 2B and GL2 on chromosome 3B,and eight candidate genes were identified within their corresponding intervals(2B:63.6–70.4 Mb;3B:631.5–633.3 Mb).These genes encode proteins potentially involved in grain size regulation,including a TOR2 regulation-associated protein,erect spike 2(EP2),fibroblast growth factor 6(FGF6),cellulose synthase-like(CSLD),RelA/pot homologue three family protein,and three GDSL esterase/lipase(GLIP)proteins.Additionally,we detected a QTL associated with GW on chromosome 3A and identified two candidate genes,TOR2 regulation and starch synthase within the 61.4–68.5 Mb interval.Overall,this study provides a strong theoretical and technical basis for wheat genetic improvement and offers valuable resources for precise QTL mapping and candidate gene discovery.展开更多
Large grain is a favorable trait for appearance quality and a large sink potential in wheat breeding.The stable QTL QGl.caas-5BS for grain length was previously identified in a recombinant inbred line population from ...Large grain is a favorable trait for appearance quality and a large sink potential in wheat breeding.The stable QTL QGl.caas-5BS for grain length was previously identified in a recombinant inbred line population from the cross of Zhongmai 871(ZM871)and its sister line Zhongmai 895(ZM895).Here,a BC_(1)F_6 residual heterozygous line was selected from the cross of a ZM871/ZM895//ZM871 population,and six heterozygous recombinant plants were identified in the BC_(1)F_(7)population from self-pollination of the heterozygous line.QGl.caas-5BS was delimited into an interval of approximately 2.2 Mb flanked by markers Kasp_5B33 and Kasp_5B2(25.3-27.5 Mb)by phenotyping and genotyping the secondary mapping populations derived from these heterozygous recombinant plants.Five genes were predicted as candidates of QGl.caas-5BS based on sequence polymorphism and differential expression analyses.Further mutation analysis showed that TraesCS5B02G026800 is likely the causal gene of QGl.caas-5BS.The gene-specific marker Kasp_5B_Gl for TraesCS5B02G026800 was developed,and a significant genetic effect of QGl.caas-5BS on grain length was identified in a validation population of 166 cultivars using this marker.These findings lay a good foundation for map-based cloning of QGl.caas-5BS and provide a breeding-applicable marker for the improvement of grain length in wheat.展开更多
A residual heterozygous line （RHL） carrying a heterozygous segment between two S SR loci RM 11 and RM134 on the rice chromo- some 7 was selected from a set of recombinant inbred lines from the cross D50 （javanica）...A residual heterozygous line （RHL） carrying a heterozygous segment between two S SR loci RM 11 and RM134 on the rice chromo- some 7 was selected from a set of recombinant inbred lines from the cross D50 （javanica）/HB277 （indica）. The former parent produces much longer grains than the latter. Selfed progenies of this selection were analyzed genotypically （SSRs） and phenotypically （grain length）. Grain length was discontinuously variable in the mapping populations, allowing for the placement of this QTL qGL7-2 within a -4.8 cM interval defined by RM351 and RM234. A set of new markers within this region were developed, which narrowed the QTL to a 278 kb region defined by the markers Indell and RM21945. This region contains 49 predicted genes. The results also suggest that the novel allele for grain length will be used for the application of marker assisted selection for the improvement of grain length.展开更多
Grain size is an important determinant of grain weight and yield in rice.Although several genes related to grain size have been identified,natural variations in these genes that affect grain size are poorly characteri...Grain size is an important determinant of grain weight and yield in rice.Although several genes related to grain size have been identified,natural variations in these genes that affect grain size are poorly characterized.Here,we describe the grain length QTL GL10,encoding MADS56,which positively regulates grain length and grain weight.A natural allelic variation of NIL-gl10,containing an~1.0-kb deletion in the first exon that abolishes its transcription,results in shorter grain length,lower grain weight and delayed flowering in gl10 plants.The knockout of GL10 in the HJX74 background leads to grain phenotypes similar to that of NIL-gl10,while overexpression of GL10 results in increased grain length and weight and earlier heading date.GL10 regulates grain length by promoting greater longitudinal cell growth in the grain glume.Additionally,GL10 participates in the regulation of gibberellic acid(GA)signaling pathway genes in young panicle tissues.Analysis of GL10 haplotypes shows obvious divergence between the japonica and indica lineages.Our findings reveal an allelic variation of GL10 that may explain differences in grain length among modern cultivars and could be used to breed rice varieties with optimized grain shape.展开更多
Grain yield is a polygenic trait that can be influenced by environmental factors and genetic compositions at all plant growth stages.Currently,the molecular mechanisms behind the coordination of the interaction betwee...Grain yield is a polygenic trait that can be influenced by environmental factors and genetic compositions at all plant growth stages.Currently,the molecular mechanisms behind the coordination of the interaction between grain yield-related traits remain unknown.In this study,we characterized the function of four STRESS_tolerance and GRAIN_LENGTH(Os SGL)Poaceae ortholog genes that are transcribed into DUF1645 domain-containing proteins in relation to the grain length,grain weight,and drought stress-tolerance of rice.The transgenic plants with overexpressing or heterologous high levels of Poaceae OsSGL ortholog genes exhibited longer grain size than the wild type plants.Larger cells were seen in panicles of the four transgenic lines with paraffin sectioning and scanning electron microscopy analyses.In addition,four Poaceae OsSGL ortholog genes positively affected the drought tolerance of rice.Four transgenic plants displayed higher resistance to drought stress at the seedling and vegetative stages.RNA-sequencing and qRT-PCR results indicated that over-or heterologous-expression of four Poaceae OsSGL ortholog genes also affected the transcriptome of rice plants.These genes may play a role in auxin and cytokinin biosynthesis and their transduction pathways.Taken together,these results suggested that the four OsSGL orthologs have a conserved function in the regulation of stress-tolerance and cell growth by modulating hormonal biosynthesis and signaling.展开更多
Grain size is one of the determinants of grain yield,and identifying the genetic loci that control grain size will be helpful for increasing grain yield.In our previous study,a quantitative trait locus(QTL)for grain l...Grain size is one of the determinants of grain yield,and identifying the genetic loci that control grain size will be helpful for increasing grain yield.In our previous study,a quantitative trait locus(QTL)for grain length(GL),QGl.cau-2D.1,was identified from an F2 population developed from the cross between the natural(TAA10)and synthetic(XX329)allohexaploid wheat.In the present study,we mainly fine mapped and validated its genetic effects.To this end,multiple near-isogenic lines(NILs)were obtained through marker-assisted selection with TAA10 as the recurrent parent.The secondary populations derived from 25 heterozygous recombinants were used for fine mapping of QGl.cau-2D.1,and the allele from XX329 significantly increased GL,thousand-grain weight(TGW),total spikelet number per spike(TSN)and spike compactness(SC).Using NILs for XX329(2D+)and TAA10(2D−),we determined the genetic and pleiotropic effects of QGl.cau-2D.1.The target sequences were aligned with the wheat reference genome RefSeq v2.1 and spanned an~0.9 Mb genomic region.TraesCS2D03G0114900(ortholog of Os03g0594700)was predicted as the candidate gene based on whole-genome re-sequencing and expression analyses.In summary,the map-based cloning of QGl.cau-2D.1 will be useful for improving grain weight with enhanced GL and TSN.展开更多
Grain size influences the yield and quality of rice(Oryza sativa L.),and grain length is one of the component traits of grain size.In this study,a near-isogenic line LB3 with long grain size was constructed using japo...Grain size influences the yield and quality of rice(Oryza sativa L.),and grain length is one of the component traits of grain size.In this study,a near-isogenic line LB3 with long grain size was constructed using japonica rice cultivar 02428,with short grain size,as the recipient parent and indica rice cultivar ZYX,with long grain size,as the donor parent,by multi-generation backcrossing and selfing.BSA-seq was used for preliminary QTL mapping and InDel markers were developed to fine map the locus.The major QTL,tentatively named qGL10,for grain length was located in a 128.45 kb region of chromosome 10.Combined with haplotype analysis of rice varieties,expression pattern analysis of candidate genes suggested LOC_Os10g39130(OsMADS56)as a candidate gene.Sequence alignment of OsMADS56 in 02428 and LB3 revealed that there were 15 SNPs in the promoter region and four in the coding region.Further haplotype analysis suggested that SNP9(G/A)located in the TGTCACA motif might account for the different expression levels of OsMADS56 in 02428 and LB3.These results lay a foundation for the application of qGL10 in molecular breeding of new rice varieties.展开更多
Mapping and isolation of quantitative trait loci(QTLs)or genes controlling grain size or weight is very important to uncover the molecular mechanisms of seed development and crop breeding.To identify the QTLs controll...Mapping and isolation of quantitative trait loci(QTLs)or genes controlling grain size or weight is very important to uncover the molecular mechanisms of seed development and crop breeding.To identify the QTLs controlling grain size and weight,we developed a near isogenic line F_2(NIL-F_2)population,which was derived from a residual heterozygous plant in an F_7 generation of recombinant inbred line(RIL).With the completion of more than 30×whole genome re-sequencing of the parents,two DNA bulks for large and small grains,a total of 58.94 Gb clean nucleotide data were generated.A total of455 262 single nucleotide polymorphisms(SNPs)between the parents were identified to perform bulked QTL-seq.A candidate genomic region containing SNPs strongly associated with grain length and weight was identified from 15 to 20 Mb on chromosome 5.We designated the major QTL in the candidate region as q TGW5.3.Then,q TGW5.3 was further validated with PCR-based conventional QTL mapping method through developing simple sequence repeat and Insertion/Deletion markers in the F_2 population.Furthermore,recombinants and the progeny tests delimited the candidate region of q TGW5.3 to 1.13 Mb,flanked by HX5009(15.15 Mb)and HX5003(16.28 Mb).A set of NILs,selected from the F_2 population,was developed to evaluate the genetic effect of q TGW5.3.Significant QTL effects were detected on grain length,grain width and 1000-grain weight of H12-29 allele with 1.14 mm,-0.11 mm and 3.11 g,which explained 99.64%,95.51%and 97.32%of the phenotypic variations,respectively.展开更多
Grain size is an important agronomic trait that largely determines grain yield in rice(Oryza sativa L.).The genes encoding the Growth Regulating Factors(GRFs)and G-proteins are major regulators for grain length regula...Grain size is an important agronomic trait that largely determines grain yield in rice(Oryza sativa L.).The genes encoding the Growth Regulating Factors(GRFs)and G-proteins are major regulators for grain length regulation,but how these pathways are coordinated in plants remains elusive.Here,we described OsPLATZ1 as a transcriptional activator,a member of the Plant AT-rich sequence-and Zinc-binding family proteins in rice that positively regulates grain length.OsPLATZ1 interacted with multiple GRFs,and the OsPLATZ1-Os GRF4 complex bound to regulatory regions in the promoter of the G-protein gene DENSE AND ERECT PANICLE1(DEP1)to enhance its expression,thereby regulating grain length.We used gene editing to modify the OsPLATZ1 promoter regulatory region and obtained mutant lines with downregulated or upregulated OsPLATZ1 expression depending on the type of editing event.One of these mutant lines had changes in multiple agronomic traits and improved grain yield and grain appearance quality.Our findings reveal a new regulatory module in which OsPLATZ1 connects the GRFs and G-protein signaling pathways to regulate grain length and suggest that finely modulating OsPLATZ1activity might be a promising molecular breeding approach.展开更多
Grain size is one of the key factors determining grain weight and yield.However,it remains largely unknown how the auxin signal regulates grain size in rice.Here,a quantitative trait locus qGL1 for grain length was id...Grain size is one of the key factors determining grain weight and yield.However,it remains largely unknown how the auxin signal regulates grain size in rice.Here,a quantitative trait locus qGL1 for grain length was identified with recombinant inbred lines 9311 and Nipponbare(NIP),and fine-mapped to the OsABCB4 gene,which encodes a member of the ATP Binding Cassette B(ABCB)subfamily.Compared to NIP,loss of OsABCB4 function leads to longer and heavier grains,while over-expression of OsABCB4 causes shorter and lighter grains,demonstrating a negative control of grain length and weight in rice.Haplotype analyses using 3024 rice-sequenced genomes indicated that SNP25 and SNP55 in OsABCB4 are correlated with grain length in rice.OsbHLH166,a basic helix-loop-helix transcription factor,was screened from a yeast one-hybrid library and confirmed to directly bind the promoter of OsABCB4 by electrophoretic mobility shift assay and yeast one hybridization validation and to activate the expression of OsABCB4 by dual-luciferase reporter assay.And OsbHLH166 expressions matching OsABCB4 were all higher expressed in stems and glumes.OsABCB4 was subcellularly localized on the plasma membrane,which was verified as an auxin efflux transporter.Histological analysis,IAA content measurement and DR5:GUS activity analyses demonstrated that OsbHLH166 and OsABCB4 control grain length by regulating cell expansion and auxin contents in glume cells and altering the expression of GL7,GS2,TGW3 and GS3 genes during rice grain development.This newly identified OsbHLH166-OsABCB4 module sheds light on our understanding of molecular mechanisms underlying the regulation of grain size and weight via auxin and provides a new gene resource for molecular design breeding of grain type.展开更多
Wheat is a staple food globally.Grain size substantially affects yield by influencing grain weight.Only a few genes associated with grain yield have been cloned in wheat by omics strategies and map-based cloning.Lecti...Wheat is a staple food globally.Grain size substantially affects yield by influencing grain weight.Only a few genes associated with grain yield have been cloned in wheat by omics strategies and map-based cloning.Lectin receptor-like kinases(LecRLKs),a plant-specific RLK subfamily,are involved in plant development,seed germination,hormone signaling,and response to abiotic and biotic stresses[1].A recent study has indicated an association of LecRLKs with grain yield[2].However,the role of wheat LecRLKs in the regulation of grain size remains poorly understood.展开更多
Grain size is one of the most important factors that control rice yield,as it is associated with grain weight(GW).To date,dozens of rice genes that regulate grain size have been isolated;however,the regulatory mechani...Grain size is one of the most important factors that control rice yield,as it is associated with grain weight(GW).To date,dozens of rice genes that regulate grain size have been isolated;however,the regulatory mechanism underlying GW control is not fully understood.Here,the quantitative trait locus qGL5 for grain length(GL)and GW was identified in recombinant inbred lines of 9311 and Nipponbare(NPB)and fine mapped to a candidate gene,OsAUX3.Sequence variations between 9311 and NPB in the OsAUX3 promoter and loss of function of OsAUX3 led to higher GL and GW.RNA sequencing,gene expression quantification,dual-luciferase reporter assays,chromatin immunoprecipitation-quantitative PCR,and yeast one-hybrid assays demonstrated that OsARF6 is an upstream transcription factor regulating the expression of OsAUX3.OsARF6 binds directly to the auxin response elements of the OsAUX3 promoter,covering a single-nucleotide polymorphism site between 9311 and NPB/Dongjin/Hwayoung,and thereby controls GL by altering longitudinal expansion and auxin distribution/content in glume cells.Furthermore,we showed that miR167a positively regulate GL and GW by directing OsARF6 mRNA silencing.Taken together,our study reveals that a novel miR167a-OsARF6-OsAUX3 module regulates GL and GW in rice,providing a potential target for the improvement of rice yield.展开更多
Grain size and grain weight are important determinants for grain yield.In this study,we identify a novel OsMAPK5–OsWRKY72 module that negatively regulates grain length and grain weight in rice.We found that loss-of-f...Grain size and grain weight are important determinants for grain yield.In this study,we identify a novel OsMAPK5–OsWRKY72 module that negatively regulates grain length and grain weight in rice.We found that loss-of-function of OsMAPK5 leads to larger cell size of the rice spikelet hulls and a significant increase in both grain length and grain weight in an indica variety Minghui 86(MH86).OsMAPK5 interacts with OsMAPKK3/4/5 and OsWRKY72 and phosphorylates OsWRKY72 at T86 and S88.Similar to the osmapk5 MH86 mutants,the oswrky72 knockout MH86 mutants exhibited larger size of spikelet hull cells and increased grain length and grain weight,whereas the OsWRKY72-overexpression MH86 plants showed opposite phenotypes.OsWRKY72 targets the W-box motifs in the promoter of OsARF6,an auxin response factor involved in auxin signaling.Dual-luciferase reporter assays demonstrated that OsWRKY72 activates OsARF6 expression.The activation effect of the phosphorylation-mimicking OsWRKY72T86D/S88D on OsARF6 expression was significantly enhanced,whereas the effects of the OsWRKY72 phosphorylation-null mutants were significantly reduced.In addition,auxin levels in young panicles of the osmapk5 and oswrky72 mutants were significantly higher than that in the wild-type MH86.Collectively,our study uncovered novel connections of the OsMAPKK3/4/5-OsMAPK5-mediated MAPK signaling,OsWRKY72-mediated transcription regulation,and OsARF6-mediated auxin signaling pathways in regulating grain length and grain weight in an indica-type rice,providing promising targets for molecular breeding of rice varieties with high yield and quality.展开更多
Grain size and weight are key components of wheat yield.Exploitation of major underlying quantitative trait loci(QTL)can improve yield potential in wheat breeding.A recombinant inbred line(RIL)population was construct...Grain size and weight are key components of wheat yield.Exploitation of major underlying quantitative trait loci(QTL)can improve yield potential in wheat breeding.A recombinant inbred line(RIL)population was constructed to detect QTL for thousand-grain weight(TGW),grain length(GL)and grain width(GW)across eight environments.Genomic regions associated with grain size and grain weight were identified on chromosomes 4A and 6A using bulked segregant exome sequencing(BSE-Seq)analysis.After constructing genetic maps,six major QTL detected in at least four individual environments and in best linear unbiased estimator(BLUE)datasets,explained 7.50%-23.45%of the phenotypic variation.Except for QGl.cib-4A,the other five QTL were co-located in two regions,namely QTgw/Gw.cib-4A and QTgw/Gw/Gl.cib-6A.Interactions of these QTL were analyzed.Unlike QTgw/Gw/Gl.cib-6A,QTgw/Gw.cib-4A and QGl.cib-4A had no effect on grain number per spike(GNS).The QTL were validated in a second cross using Kompetitive Allele Specific PCR(KASP)markers.Since QTgw/Gw.cib-4A was probably a novel locus,it and the KASP markers reported here can be used in wheat breeding.TraesCS4A03G0191200 was predicted to be potential candidate gene for QTgw/Gw.cib-4A based on the sequence differences,spatiotemporal expression patterns,gene annotation and haplotype analysis.Our findings will be useful for fine mapping and for marker-assisted selection in wheat grain yield improvement.展开更多
Grain size is one of the most important agronomic traits controlling grain yield. Development of novel germplasm with large grains would be beneficial for crop improvement. We report the genetic identification and fun...Grain size is one of the most important agronomic traits controlling grain yield. Development of novel germplasm with large grains would be beneficial for crop improvement. We report the genetic identification and functional analysis of the LONG GRAIN 6(LOG6) gene, which is identical to MITOGENACTIVATED PROTEIN KINASE 6(OsMAPK6), affecting grain length of rice. Map-based cloning revealed that the long-grain phenotype of log6-D results from a glutamine(E) to lysine(K) mutation in the conserved TEY motif of OsMAPK6. In near-isogenic lines(NILs), the log6-D allele increased grain length and grain yield of Guichao 2(GC2), Teqing(TQ), and 93–11. Sequence analysis revealed 10 OsMAPK6 haplotypes,with xian(indica) and geng(japonica) harboring different haplotypes. Our findings shed light on the function of MAPKs and offer a novel dominant allele for improving the grain yield of rice.展开更多
The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed i...The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed in young spikelets and glumes.Its overexpression led to enlarged seeds with increased width and decreased length/width ratio(LWR)and knocking out OsDA1 reduced grain width and increased grain length and LWR.A R310K point mutation in the DA1-like domain is a potential target for breeding for increased grain width and length.OsDA1 interacted with TCP gene-family proteins to regulate grain size and shape.Our findings deepen our understanding of the molecular mechanisms underlying grain size regulation and provide useful information for improving grain yield.展开更多
To create the japonica germplasm with long grain and fragrance,we edited GS3 and OsBADH2 of a japonica rice cultivar Chunjiang 151 by using CRISPR/Cas9 system for multiplex genome editing.10 long-grain fragrant japoni...To create the japonica germplasm with long grain and fragrance,we edited GS3 and OsBADH2 of a japonica rice cultivar Chunjiang 151 by using CRISPR/Cas9 system for multiplex genome editing.10 long-grain fragrant japonica rice plants without transgenic components were obtained.Compared with those of Chunjiang 151,the grain length,thousand-grain weight,and yield per plant of the edited line increased 12.20%,18.45%,and 8.31%,respectively.We created the fragrant japonica rice line with improved grain length and yield,which enriched the germplasm resource of japonica rice and provided reference for the improvement of rice quality.展开更多
Thousand-grain weight (TGW) is a key component of grain yield in rice. This study was conducted to validate and fine-map qTGW1.2a, a quantitative trait locus for grain weight and grain size previously located in a 933...Thousand-grain weight (TGW) is a key component of grain yield in rice. This study was conducted to validate and fine-map qTGW1.2a, a quantitative trait locus for grain weight and grain size previously located in a 933.6-kb region on the long arm of rice chromosome 1. Firstly, three residual heterozygotes (RHs) were selected from a BC2F11 population of the indica rice cross Zhenshan 97 (ZS97)///ZS97//ZS97/Milyang 46. The heterozygous segments in these RHs were arranged successively in physical positions, forming one set of sequential residual heterozygotes (SeqRHs). In each of the populations derived, non-recombinant homozygotes were identified to produce near isogenic lines (NILs) comprising the two homozygous genotypes. The NILs were tested for grain weight, grain length and grain width. QTL analyses for the three traits were performed. Then, the updated QTL location was followed for a new run of SeqRHs identification-NIL development-QTL mapping. Altogether, 11 NIL populations derived from four sets of SeqRHs were developed and used. qTGW1.2a was finally delimitated into a 77.5-kb region containing 13 annotated genes. In the six populations segregating this QTL, which were in four generations and were tested across four years, the allelic direction of qTGW1.2a remained consistent and the genetic effects were stable. For TGW, the additive effects ranged from 0.23 to 0.38 g and the proportions of phenotypic variance explained ranged from 26.15% to 41.65%. These results provide a good foundation for the cloning and functional analysis of qTGW1.2a.展开更多
Grain weight is one of themost important determinants of grain yield in rice.In this study,QTL analysis for grain weight,grain length,and grainwidthwas performed using populations derived from crosses between major pa...Grain weight is one of themost important determinants of grain yield in rice.In this study,QTL analysis for grain weight,grain length,and grainwidthwas performed using populations derived from crosses between major parental lines of three-line indica hybrid rice.A total of 27 QTL for grain weight were detected using three recombinant inbred line populations derived from the crosses Teqing/IRBB lines,Zhenshan 97/Milyang 46,and Xieqingzao/Milyang 46.Of these,10 were found in only a single population and the other 17 in two or all three populations.Nine of the 17 common QTL were located in regions where no QTL associated with grain weight have been cloned and onewas selected for fine-mapping.Eight populations segregating in an isogenic background were derived from one F7 residual heterozygote of Teqing/IRBB52.The target QTL,qTGW10-20.8 controlling grain weight,grain length,and grain width,was localized to a 70.7-kb region flanked by InDel markers Te20811 and Te20882 on the long arm of chromosome 10.The QTL region contains seven annotated genes,ofwhich six encode proteins with known functional domains and one encodes a hypothetical protein.One of the genes,Os10g0536100 encoding the MIKC-type MADS-box protein OsMADS56,is the most likely candidate for qTGW10-20.8.These results provide a basis for cloning qTGW10-20.8,which has an important contribution to grain weight variation in rice.展开更多
基金supported by STI 2030-Major Project(2023ZD04069)the National Natural Science Foundation of China(32472129,U24A20392,32201841)+1 种基金Regional Joint Youth Fund for Basic and Applied Basic Research Foundation of Guangdong Province(2022 A1515110454)Science and Technology Projects in Guangzhou(2023B03J1355).
文摘Grain size is a crucial factor influencing both rice yield and appearance quality.In this study,we identified GL6.1 as a gene associated with rice grain size by map-based cloning.The GL6.1 encodes a protein with CC-NB-LRR domain,a structural motif related to rice disease resistance.Genetic transformation experiments and the construction of gene pyramiding lines indicate that GL6.1 functions as a negative regulatory factor for rice grain length.By the analysis of SSSLs with diverse donor parents,a total of 11 single nucleotide polymorphisms(SNPs)are identified that are closely associated with the phenotype variations.A yeast one-hybrid library screening revealed that GL6.1 interacts with OsWRKY53,a transcription factor associated with rice disease resistance.Furthermore,RNA-seq assay also revealed the involvement of pathways associated with disease resistance,hinting at a multifaceted role for GL6.1 in both yield and stress tolerance traits in rice.These results indicate that the cloning and in-depth studies of GL6.1 would provide valuable insights into the interplay among high yield,superior quality,and stress tolerance,which are critical goals for rice breeding.
基金Funding for this project was provided by the National Natural Science Foundation of China(Grants No.32160456,32360474,32360486,32260496)the Key Laboratory of Functional Agriculture of Guizhou Provincial Higher Education Institutions(Grant No.Qianjiaoji(2023)007).
文摘Wheat grain morphology,particularly grain length(GL)and width(GW),is a key determinant of yield.To improve the suboptimal grain dimensions of the local anthocyanin-rich variety Guizi 1(GZ1),we crossed it with Zhongyan 96-3(ZY96-3),an elite germplasm known for faster grain filling and superior grain size.A genotyping-by-sequencing(GBS)approach was applied to an F_(2)population of 110 individuals derived from GZ1×ZY96-3,resulting in the identification of 23,134 high-quality SNPs.Most of the SNPs associated with GL and GW were clustered on chromosomes 2B,3A,and 3B.QTL mapping for GL revealed two major loci,GL1 on chromosome 2B and GL2 on chromosome 3B,and eight candidate genes were identified within their corresponding intervals(2B:63.6–70.4 Mb;3B:631.5–633.3 Mb).These genes encode proteins potentially involved in grain size regulation,including a TOR2 regulation-associated protein,erect spike 2(EP2),fibroblast growth factor 6(FGF6),cellulose synthase-like(CSLD),RelA/pot homologue three family protein,and three GDSL esterase/lipase(GLIP)proteins.Additionally,we detected a QTL associated with GW on chromosome 3A and identified two candidate genes,TOR2 regulation and starch synthase within the 61.4–68.5 Mb interval.Overall,this study provides a strong theoretical and technical basis for wheat genetic improvement and offers valuable resources for precise QTL mapping and candidate gene discovery.
基金funded by the National Natural Science Foundation of China(31961143007)the Key Research and Development Program of Xinjiang Uygur Autonomous Region,China(2023B02006)+1 种基金the Core Research Budget of the Non-profit Governmental Research Institutions,Institute of Crop Sciences,Chinese Academy of Agricultural Sciences(S2021ZD04 and S2022ZD04)the Natural Science Foundation of Hebei Province,China(C2021205013)。
文摘Large grain is a favorable trait for appearance quality and a large sink potential in wheat breeding.The stable QTL QGl.caas-5BS for grain length was previously identified in a recombinant inbred line population from the cross of Zhongmai 871(ZM871)and its sister line Zhongmai 895(ZM895).Here,a BC_(1)F_6 residual heterozygous line was selected from the cross of a ZM871/ZM895//ZM871 population,and six heterozygous recombinant plants were identified in the BC_(1)F_(7)population from self-pollination of the heterozygous line.QGl.caas-5BS was delimited into an interval of approximately 2.2 Mb flanked by markers Kasp_5B33 and Kasp_5B2(25.3-27.5 Mb)by phenotyping and genotyping the secondary mapping populations derived from these heterozygous recombinant plants.Five genes were predicted as candidates of QGl.caas-5BS based on sequence polymorphism and differential expression analyses.Further mutation analysis showed that TraesCS5B02G026800 is likely the causal gene of QGl.caas-5BS.The gene-specific marker Kasp_5B_Gl for TraesCS5B02G026800 was developed,and a significant genetic effect of QGl.caas-5BS on grain length was identified in a validation population of 166 cultivars using this marker.These findings lay a good foundation for map-based cloning of QGl.caas-5BS and provide a breeding-applicable marker for the improvement of grain length in wheat.
基金supported by the National High-tech R&D Program (863 Program) (No. 2009AA101101)the National S&T Major Project (No. 2008ZX08001)the Central Level, Non-profit, Scientific Research Insti-tutes’ Basic R&D Operations Special Fund (No. 2009RG002-3)
文摘A residual heterozygous line （RHL） carrying a heterozygous segment between two S SR loci RM 11 and RM134 on the rice chromo- some 7 was selected from a set of recombinant inbred lines from the cross D50 （javanica）/HB277 （indica）. The former parent produces much longer grains than the latter. Selfed progenies of this selection were analyzed genotypically （SSRs） and phenotypically （grain length）. Grain length was discontinuously variable in the mapping populations, allowing for the placement of this QTL qGL7-2 within a -4.8 cM interval defined by RM351 and RM234. A set of new markers within this region were developed, which narrowed the QTL to a 278 kb region defined by the markers Indell and RM21945. This region contains 49 predicted genes. The results also suggest that the novel allele for grain length will be used for the application of marker assisted selection for the improvement of grain length.
基金supported by the National Natural Science Foundation of China (32072040, 31622041)the Key Projects of Basic Research and Applied Basic Research of Guangdong Province(2019B030302006)
文摘Grain size is an important determinant of grain weight and yield in rice.Although several genes related to grain size have been identified,natural variations in these genes that affect grain size are poorly characterized.Here,we describe the grain length QTL GL10,encoding MADS56,which positively regulates grain length and grain weight.A natural allelic variation of NIL-gl10,containing an~1.0-kb deletion in the first exon that abolishes its transcription,results in shorter grain length,lower grain weight and delayed flowering in gl10 plants.The knockout of GL10 in the HJX74 background leads to grain phenotypes similar to that of NIL-gl10,while overexpression of GL10 results in increased grain length and weight and earlier heading date.GL10 regulates grain length by promoting greater longitudinal cell growth in the grain glume.Additionally,GL10 participates in the regulation of gibberellic acid(GA)signaling pathway genes in young panicle tissues.Analysis of GL10 haplotypes shows obvious divergence between the japonica and indica lineages.Our findings reveal an allelic variation of GL10 that may explain differences in grain length among modern cultivars and could be used to breed rice varieties with optimized grain shape.
基金supported by the National Natural Science Foundation of China(Grant Nos.31501393,31671671 and 31671612)the Open Research Fund of State Key Laboratory of Hybrid Rice(Wuhan University,China)(Grant No.KF201803)。
文摘Grain yield is a polygenic trait that can be influenced by environmental factors and genetic compositions at all plant growth stages.Currently,the molecular mechanisms behind the coordination of the interaction between grain yield-related traits remain unknown.In this study,we characterized the function of four STRESS_tolerance and GRAIN_LENGTH(Os SGL)Poaceae ortholog genes that are transcribed into DUF1645 domain-containing proteins in relation to the grain length,grain weight,and drought stress-tolerance of rice.The transgenic plants with overexpressing or heterologous high levels of Poaceae OsSGL ortholog genes exhibited longer grain size than the wild type plants.Larger cells were seen in panicles of the four transgenic lines with paraffin sectioning and scanning electron microscopy analyses.In addition,four Poaceae OsSGL ortholog genes positively affected the drought tolerance of rice.Four transgenic plants displayed higher resistance to drought stress at the seedling and vegetative stages.RNA-sequencing and qRT-PCR results indicated that over-or heterologous-expression of four Poaceae OsSGL ortholog genes also affected the transcriptome of rice plants.These genes may play a role in auxin and cytokinin biosynthesis and their transduction pathways.Taken together,these results suggested that the four OsSGL orthologs have a conserved function in the regulation of stress-tolerance and cell growth by modulating hormonal biosynthesis and signaling.
基金supported by the National Key Research and Development Program of China(32172069).
文摘Grain size is one of the determinants of grain yield,and identifying the genetic loci that control grain size will be helpful for increasing grain yield.In our previous study,a quantitative trait locus(QTL)for grain length(GL),QGl.cau-2D.1,was identified from an F2 population developed from the cross between the natural(TAA10)and synthetic(XX329)allohexaploid wheat.In the present study,we mainly fine mapped and validated its genetic effects.To this end,multiple near-isogenic lines(NILs)were obtained through marker-assisted selection with TAA10 as the recurrent parent.The secondary populations derived from 25 heterozygous recombinants were used for fine mapping of QGl.cau-2D.1,and the allele from XX329 significantly increased GL,thousand-grain weight(TGW),total spikelet number per spike(TSN)and spike compactness(SC).Using NILs for XX329(2D+)and TAA10(2D−),we determined the genetic and pleiotropic effects of QGl.cau-2D.1.The target sequences were aligned with the wheat reference genome RefSeq v2.1 and spanned an~0.9 Mb genomic region.TraesCS2D03G0114900(ortholog of Os03g0594700)was predicted as the candidate gene based on whole-genome re-sequencing and expression analyses.In summary,the map-based cloning of QGl.cau-2D.1 will be useful for improving grain weight with enhanced GL and TSN.
基金supported by the Guangdong Provincial Key R&D Program(2021B0707010010)the Key R&D Program of Guangzhou Science and Technology Project(202103000083).
文摘Grain size influences the yield and quality of rice(Oryza sativa L.),and grain length is one of the component traits of grain size.In this study,a near-isogenic line LB3 with long grain size was constructed using japonica rice cultivar 02428,with short grain size,as the recipient parent and indica rice cultivar ZYX,with long grain size,as the donor parent,by multi-generation backcrossing and selfing.BSA-seq was used for preliminary QTL mapping and InDel markers were developed to fine map the locus.The major QTL,tentatively named qGL10,for grain length was located in a 128.45 kb region of chromosome 10.Combined with haplotype analysis of rice varieties,expression pattern analysis of candidate genes suggested LOC_Os10g39130(OsMADS56)as a candidate gene.Sequence alignment of OsMADS56 in 02428 and LB3 revealed that there were 15 SNPs in the promoter region and four in the coding region.Further haplotype analysis suggested that SNP9(G/A)located in the TGTCACA motif might account for the different expression levels of OsMADS56 in 02428 and LB3.These results lay a foundation for the application of qGL10 in molecular breeding of new rice varieties.
基金supported by National Natural Science Foundation of China(Grant No.31371605)Chinese High-Yielding Transgenic Program(Grant No.2016ZX08001-004)
文摘Mapping and isolation of quantitative trait loci(QTLs)or genes controlling grain size or weight is very important to uncover the molecular mechanisms of seed development and crop breeding.To identify the QTLs controlling grain size and weight,we developed a near isogenic line F_2(NIL-F_2)population,which was derived from a residual heterozygous plant in an F_7 generation of recombinant inbred line(RIL).With the completion of more than 30×whole genome re-sequencing of the parents,two DNA bulks for large and small grains,a total of 58.94 Gb clean nucleotide data were generated.A total of455 262 single nucleotide polymorphisms(SNPs)between the parents were identified to perform bulked QTL-seq.A candidate genomic region containing SNPs strongly associated with grain length and weight was identified from 15 to 20 Mb on chromosome 5.We designated the major QTL in the candidate region as q TGW5.3.Then,q TGW5.3 was further validated with PCR-based conventional QTL mapping method through developing simple sequence repeat and Insertion/Deletion markers in the F_2 population.Furthermore,recombinants and the progeny tests delimited the candidate region of q TGW5.3 to 1.13 Mb,flanked by HX5009(15.15 Mb)and HX5003(16.28 Mb).A set of NILs,selected from the F_2 population,was developed to evaluate the genetic effect of q TGW5.3.Significant QTL effects were detected on grain length,grain width and 1000-grain weight of H12-29 allele with 1.14 mm,-0.11 mm and 3.11 g,which explained 99.64%,95.51%and 97.32%of the phenotypic variations,respectively.
基金supported by grants from the National Natural Science Foundation of China(32100278)the China Postdoctoral Science Foundation(2023M741225)the Postdoctoral Fellowship Program(Grade C)of China Postdoctoral Science Foundation(GZC20230864)。
文摘Grain size is an important agronomic trait that largely determines grain yield in rice(Oryza sativa L.).The genes encoding the Growth Regulating Factors(GRFs)and G-proteins are major regulators for grain length regulation,but how these pathways are coordinated in plants remains elusive.Here,we described OsPLATZ1 as a transcriptional activator,a member of the Plant AT-rich sequence-and Zinc-binding family proteins in rice that positively regulates grain length.OsPLATZ1 interacted with multiple GRFs,and the OsPLATZ1-Os GRF4 complex bound to regulatory regions in the promoter of the G-protein gene DENSE AND ERECT PANICLE1(DEP1)to enhance its expression,thereby regulating grain length.We used gene editing to modify the OsPLATZ1 promoter regulatory region and obtained mutant lines with downregulated or upregulated OsPLATZ1 expression depending on the type of editing event.One of these mutant lines had changes in multiple agronomic traits and improved grain yield and grain appearance quality.Our findings reveal a new regulatory module in which OsPLATZ1 connects the GRFs and G-protein signaling pathways to regulate grain length and suggest that finely modulating OsPLATZ1activity might be a promising molecular breeding approach.
基金supported by the National Natural Science Foundation of China(32188102,32372073,and 32301911)the Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-CSNCB-202301)+4 种基金the Natural Science Foundation of Nei Mongol(2022ZD11)the Science Technology Plan Project of Nei Mongol(2023YFDZ0007)the Swiss National Funds(310030_197563)the 2024 Science and Technology Support Project of the Nei Mongol Innovation Center of Biological Breeding Technology(2024NSZC06)the Opening/Autonomous Fund of Key Laboratory of Herbage and Endemic Crop Biology,Ministry of Education,IMU(HECB2024AF01).
文摘Grain size is one of the key factors determining grain weight and yield.However,it remains largely unknown how the auxin signal regulates grain size in rice.Here,a quantitative trait locus qGL1 for grain length was identified with recombinant inbred lines 9311 and Nipponbare(NIP),and fine-mapped to the OsABCB4 gene,which encodes a member of the ATP Binding Cassette B(ABCB)subfamily.Compared to NIP,loss of OsABCB4 function leads to longer and heavier grains,while over-expression of OsABCB4 causes shorter and lighter grains,demonstrating a negative control of grain length and weight in rice.Haplotype analyses using 3024 rice-sequenced genomes indicated that SNP25 and SNP55 in OsABCB4 are correlated with grain length in rice.OsbHLH166,a basic helix-loop-helix transcription factor,was screened from a yeast one-hybrid library and confirmed to directly bind the promoter of OsABCB4 by electrophoretic mobility shift assay and yeast one hybridization validation and to activate the expression of OsABCB4 by dual-luciferase reporter assay.And OsbHLH166 expressions matching OsABCB4 were all higher expressed in stems and glumes.OsABCB4 was subcellularly localized on the plasma membrane,which was verified as an auxin efflux transporter.Histological analysis,IAA content measurement and DR5:GUS activity analyses demonstrated that OsbHLH166 and OsABCB4 control grain length by regulating cell expansion and auxin contents in glume cells and altering the expression of GL7,GS2,TGW3 and GS3 genes during rice grain development.This newly identified OsbHLH166-OsABCB4 module sheds light on our understanding of molecular mechanisms underlying the regulation of grain size and weight via auxin and provides a new gene resource for molecular design breeding of grain type.
基金funded by the National Key Research and Development Program(2023YFD1200403)the Henan Natural Science Foundation(24HASTIT055,252300421246,and 25A210020)of China.
文摘Wheat is a staple food globally.Grain size substantially affects yield by influencing grain weight.Only a few genes associated with grain yield have been cloned in wheat by omics strategies and map-based cloning.Lectin receptor-like kinases(LecRLKs),a plant-specific RLK subfamily,are involved in plant development,seed germination,hormone signaling,and response to abiotic and biotic stresses[1].A recent study has indicated an association of LecRLKs with grain yield[2].However,the role of wheat LecRLKs in the regulation of grain size remains poorly understood.
基金This project was funded by grants from the National Key Research and Development Program of China(2016YFD0100400)the National Natural Science Foundation of China(32060451)the Zhejiang Provincial Nat-ural Science Foundation of China(grant no.L Z19C020001).
文摘Grain size is one of the most important factors that control rice yield,as it is associated with grain weight(GW).To date,dozens of rice genes that regulate grain size have been isolated;however,the regulatory mechanism underlying GW control is not fully understood.Here,the quantitative trait locus qGL5 for grain length(GL)and GW was identified in recombinant inbred lines of 9311 and Nipponbare(NPB)and fine mapped to a candidate gene,OsAUX3.Sequence variations between 9311 and NPB in the OsAUX3 promoter and loss of function of OsAUX3 led to higher GL and GW.RNA sequencing,gene expression quantification,dual-luciferase reporter assays,chromatin immunoprecipitation-quantitative PCR,and yeast one-hybrid assays demonstrated that OsARF6 is an upstream transcription factor regulating the expression of OsAUX3.OsARF6 binds directly to the auxin response elements of the OsAUX3 promoter,covering a single-nucleotide polymorphism site between 9311 and NPB/Dongjin/Hwayoung,and thereby controls GL by altering longitudinal expansion and auxin distribution/content in glume cells.Furthermore,we showed that miR167a positively regulate GL and GW by directing OsARF6 mRNA silencing.Taken together,our study reveals that a novel miR167a-OsARF6-OsAUX3 module regulates GL and GW in rice,providing a potential target for the improvement of rice yield.
基金funded by grants from Fujian Provincial Science and Technology Key Project(2022NZ030014)National Natural Science Foundation of China(32071941)+1 种基金Natural Science Foundation of Fujian Province(2023J011418)Minjiang University(MJY22023).
文摘Grain size and grain weight are important determinants for grain yield.In this study,we identify a novel OsMAPK5–OsWRKY72 module that negatively regulates grain length and grain weight in rice.We found that loss-of-function of OsMAPK5 leads to larger cell size of the rice spikelet hulls and a significant increase in both grain length and grain weight in an indica variety Minghui 86(MH86).OsMAPK5 interacts with OsMAPKK3/4/5 and OsWRKY72 and phosphorylates OsWRKY72 at T86 and S88.Similar to the osmapk5 MH86 mutants,the oswrky72 knockout MH86 mutants exhibited larger size of spikelet hull cells and increased grain length and grain weight,whereas the OsWRKY72-overexpression MH86 plants showed opposite phenotypes.OsWRKY72 targets the W-box motifs in the promoter of OsARF6,an auxin response factor involved in auxin signaling.Dual-luciferase reporter assays demonstrated that OsWRKY72 activates OsARF6 expression.The activation effect of the phosphorylation-mimicking OsWRKY72T86D/S88D on OsARF6 expression was significantly enhanced,whereas the effects of the OsWRKY72 phosphorylation-null mutants were significantly reduced.In addition,auxin levels in young panicles of the osmapk5 and oswrky72 mutants were significantly higher than that in the wild-type MH86.Collectively,our study uncovered novel connections of the OsMAPKK3/4/5-OsMAPK5-mediated MAPK signaling,OsWRKY72-mediated transcription regulation,and OsARF6-mediated auxin signaling pathways in regulating grain length and grain weight in an indica-type rice,providing promising targets for molecular breeding of rice varieties with high yield and quality.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA24030402)Sichuan Science and Technology Program.
文摘Grain size and weight are key components of wheat yield.Exploitation of major underlying quantitative trait loci(QTL)can improve yield potential in wheat breeding.A recombinant inbred line(RIL)population was constructed to detect QTL for thousand-grain weight(TGW),grain length(GL)and grain width(GW)across eight environments.Genomic regions associated with grain size and grain weight were identified on chromosomes 4A and 6A using bulked segregant exome sequencing(BSE-Seq)analysis.After constructing genetic maps,six major QTL detected in at least four individual environments and in best linear unbiased estimator(BLUE)datasets,explained 7.50%-23.45%of the phenotypic variation.Except for QGl.cib-4A,the other five QTL were co-located in two regions,namely QTgw/Gw.cib-4A and QTgw/Gw/Gl.cib-6A.Interactions of these QTL were analyzed.Unlike QTgw/Gw/Gl.cib-6A,QTgw/Gw.cib-4A and QGl.cib-4A had no effect on grain number per spike(GNS).The QTL were validated in a second cross using Kompetitive Allele Specific PCR(KASP)markers.Since QTgw/Gw.cib-4A was probably a novel locus,it and the KASP markers reported here can be used in wheat breeding.TraesCS4A03G0191200 was predicted to be potential candidate gene for QTgw/Gw.cib-4A based on the sequence differences,spatiotemporal expression patterns,gene annotation and haplotype analysis.Our findings will be useful for fine mapping and for marker-assisted selection in wheat grain yield improvement.
基金supported by the National Natural Science Foundation of China (91935302, 31971870)。
文摘Grain size is one of the most important agronomic traits controlling grain yield. Development of novel germplasm with large grains would be beneficial for crop improvement. We report the genetic identification and functional analysis of the LONG GRAIN 6(LOG6) gene, which is identical to MITOGENACTIVATED PROTEIN KINASE 6(OsMAPK6), affecting grain length of rice. Map-based cloning revealed that the long-grain phenotype of log6-D results from a glutamine(E) to lysine(K) mutation in the conserved TEY motif of OsMAPK6. In near-isogenic lines(NILs), the log6-D allele increased grain length and grain yield of Guichao 2(GC2), Teqing(TQ), and 93–11. Sequence analysis revealed 10 OsMAPK6 haplotypes,with xian(indica) and geng(japonica) harboring different haplotypes. Our findings shed light on the function of MAPKs and offer a novel dominant allele for improving the grain yield of rice.
基金This work is supported in part by the National Transgenic Science and Technology Program(2016ZX08010-002)National Natural Science Foundation of China(157101834)Agricultural Science and Technology Innovation Program of CAAS.
文摘The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed in young spikelets and glumes.Its overexpression led to enlarged seeds with increased width and decreased length/width ratio(LWR)and knocking out OsDA1 reduced grain width and increased grain length and LWR.A R310K point mutation in the DA1-like domain is a potential target for breeding for increased grain width and length.OsDA1 interacted with TCP gene-family proteins to regulate grain size and shape.Our findings deepen our understanding of the molecular mechanisms underlying grain size regulation and provide useful information for improving grain yield.
文摘To create the japonica germplasm with long grain and fragrance,we edited GS3 and OsBADH2 of a japonica rice cultivar Chunjiang 151 by using CRISPR/Cas9 system for multiplex genome editing.10 long-grain fragrant japonica rice plants without transgenic components were obtained.Compared with those of Chunjiang 151,the grain length,thousand-grain weight,and yield per plant of the edited line increased 12.20%,18.45%,and 8.31%,respectively.We created the fragrant japonica rice line with improved grain length and yield,which enriched the germplasm resource of japonica rice and provided reference for the improvement of rice quality.
基金funded by the National Key R&D Program of China (Grant No. 2017YFD0100305)the National Natural Science Foundation of China (Grant No. 31521064)a project of the China National Rice Research Institute (Grant No. 2017RG001-2)
文摘Thousand-grain weight (TGW) is a key component of grain yield in rice. This study was conducted to validate and fine-map qTGW1.2a, a quantitative trait locus for grain weight and grain size previously located in a 933.6-kb region on the long arm of rice chromosome 1. Firstly, three residual heterozygotes (RHs) were selected from a BC2F11 population of the indica rice cross Zhenshan 97 (ZS97)///ZS97//ZS97/Milyang 46. The heterozygous segments in these RHs were arranged successively in physical positions, forming one set of sequential residual heterozygotes (SeqRHs). In each of the populations derived, non-recombinant homozygotes were identified to produce near isogenic lines (NILs) comprising the two homozygous genotypes. The NILs were tested for grain weight, grain length and grain width. QTL analyses for the three traits were performed. Then, the updated QTL location was followed for a new run of SeqRHs identification-NIL development-QTL mapping. Altogether, 11 NIL populations derived from four sets of SeqRHs were developed and used. qTGW1.2a was finally delimitated into a 77.5-kb region containing 13 annotated genes. In the six populations segregating this QTL, which were in four generations and were tested across four years, the allelic direction of qTGW1.2a remained consistent and the genetic effects were stable. For TGW, the additive effects ranged from 0.23 to 0.38 g and the proportions of phenotypic variance explained ranged from 26.15% to 41.65%. These results provide a good foundation for the cloning and functional analysis of qTGW1.2a.
基金supported by the National Key Research and Development Program of China (2016YFD0101104)the National Natural Science Foundation of China (31521064)project of the China National Rice Research Institute (2017RG001-2)
文摘Grain weight is one of themost important determinants of grain yield in rice.In this study,QTL analysis for grain weight,grain length,and grainwidthwas performed using populations derived from crosses between major parental lines of three-line indica hybrid rice.A total of 27 QTL for grain weight were detected using three recombinant inbred line populations derived from the crosses Teqing/IRBB lines,Zhenshan 97/Milyang 46,and Xieqingzao/Milyang 46.Of these,10 were found in only a single population and the other 17 in two or all three populations.Nine of the 17 common QTL were located in regions where no QTL associated with grain weight have been cloned and onewas selected for fine-mapping.Eight populations segregating in an isogenic background were derived from one F7 residual heterozygote of Teqing/IRBB52.The target QTL,qTGW10-20.8 controlling grain weight,grain length,and grain width,was localized to a 70.7-kb region flanked by InDel markers Te20811 and Te20882 on the long arm of chromosome 10.The QTL region contains seven annotated genes,ofwhich six encode proteins with known functional domains and one encodes a hypothetical protein.One of the genes,Os10g0536100 encoding the MIKC-type MADS-box protein OsMADS56,is the most likely candidate for qTGW10-20.8.These results provide a basis for cloning qTGW10-20.8,which has an important contribution to grain weight variation in rice.
