Powdery mildew negatively impacts wheat yield and quality.Emmer wheat(Triticum dicoccum),an ancestral species of common wheat,is a gene donor for wheat improvement.Cultivated emmer accession H1-707 exhibited all-stage...Powdery mildew negatively impacts wheat yield and quality.Emmer wheat(Triticum dicoccum),an ancestral species of common wheat,is a gene donor for wheat improvement.Cultivated emmer accession H1-707 exhibited all-stage resistance to powdery mildew over consecutive years.Genetic analysis of H1-707 at the seedling stage revealed a dominant monogenic inheritance pattern,and the underlying gene was designated Pm71.By employing bulked segregant exome sequencing(BSE-Seq)and using 2000 F2:3 families,Pm71 was fine mapped to a 336-kb interval on chromosome arm 6AS by referencing to the durum cv.Svevo RefSeq 1.0.Collinearity analysis revealed high homology in the candidate interval between Svevo and six Triticum species.Among six high-confidence genes annotated within this interval,TRITD6Av1G005050 encoding a GDSL esterase/lipase was identified as a key candidate for Pm71.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
Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,j...Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,je0407,with an 84.34%-89.35%smaller flag leaf angle compared with the wild type.The mutant also had an abnormal lamina joint and no ligule or auricle.Genetic analysis indicated that the ligule was controlled by two recessive genes,which were mapped to chromosomes 2AS and 2DL.The mutant allele on chromosome 2AS was named Tafla1b,and it was fine mapped to a 1 Mb physical interval.The mutant allele on chr.2DL was identified as Taspl8b,a novel allele of TaSPL8 with a missense mutation in the second exon,which was used to develop a cleaved amplified polymorphic sequence marker.F3 and F4 lines derived from crosses between Jing411 and je0407 were genotyped to investigate interactions between the Tafla1b and Taspl8b alleles.Plants with the Tafla1b/Taspl8a genotype had 58.41%-82.76%smaller flag leaf angles,6.4%-24.9%shorter spikes,and a greater spikelet density(0.382 more spikelets per cm)compared with the wild type.Plants with the Tafla1a/Taspl8b genotype had 52.62%-82.24%smaller flag leaf angles and no differences in plant height or spikelet density compared with the wild type.Tafla1b/Taspl8b plants produced erect leaves with an abnormal lamina joint.The two alleles had dosage effects on ligule formation and flag leaf angle,but no significant effect on thousand-grain weight.The mutant alleles provide novel resources for improvement of wheat plant architecture.展开更多
The application of a male-sterile line is an ideal approach for hybrid seed production in non-heading Chinese cabbage(Brassica rapa ssp.chinensis).However,the molecular mechanisms underlying male sterility in B.rapa a...The application of a male-sterile line is an ideal approach for hybrid seed production in non-heading Chinese cabbage(Brassica rapa ssp.chinensis).However,the molecular mechanisms underlying male sterility in B.rapa are still largely unclear.We previously obtained the natural male sterile line WS24-3 of non-heading Chinese cabbage and located the male sterile locus,Bra2Ms,on the A2 chromosome.Cytological observations revealed that the male sterility of WS24-3 resulted from disruption of the meiosis process during pollen formation.Fine mapping of Bra2Ms delimited the locus within a physical distance of about 129 kb on the A2 chromosome of B.rapa.The Bra039753 gene encodes a plant homeodomain(PHD)-finger protein and is considered a potential candidate gene for Bra2Ms.Bra039753 was significantly downregulated in sterile line WS24-3 compared to the fertile line at the meiotic anther stage.Sequence analysis of Bra039753 identified a 369 bp fragment insertion in the first exon in male sterile plants,which led to an amino acid insertion in the Bra039753 protein.In addition,the 369 bp fragment insertion was found to cosegregate with the male sterility trait.This study identified a novel locus related to male sterility in non-heading Chinese cabbage,and the molecular marker obtained in this study will be beneficial for the marker-assisted selection of excellent sterile lines in non-heading Chinese cabbage and other Brassica crops.展开更多
In a wheat breeding line XQ-0508 showing consistent resistance to powdery mildew disease,a recessive gene,designated PmXQ-0508,was identified and mapped to a distal region on chromosome arm 2BS.Of three resistance-ass...In a wheat breeding line XQ-0508 showing consistent resistance to powdery mildew disease,a recessive gene,designated PmXQ-0508,was identified and mapped to a distal region on chromosome arm 2BS.Of three resistance-associated genes in this region,one encoding a protein kinase was selected as the primary candidate for PmXQ-0508.Ten closely linked DNA markers developed in the study could be used for marker-assisted selection for powdery-mildew resistance in breeding programs.展开更多
The ast ( anthocyanin spotted testa) mutant, which was induced by carbon ion radiation, was a single recessive gene mutant of Arabidopsis thaliana (L.) Heynh. with spotted pigment in seed coats, and involved in the an...The ast ( anthocyanin spotted testa) mutant, which was induced by carbon ion radiation, was a single recessive gene mutant of Arabidopsis thaliana (L.) Heynh. with spotted pigment in seed coats, and involved in the anthocyanin biosynthesis. To clone the AST gene by map-based cloning strategy, a series of molecular markers were designed according to the SNPs (single nucleotide polymophisms) and insertion/deletion polymophisms in the Arabidopsis database. With these molecular markers, the fine-structure mapping of the AST gene was finished, the AST locus was located in BAC clone T13M11. It was suggested that the AST candidate gene was T13M11. 8 in the T13M11 This gene was 1432 bp long with 6 exons and 5 introns. The putative protein of T13M11. 8 gene was similar to dihydroflavonol 4-reductase (DFR), which was an important enzyme in the anthocyanin biosynthesis pathway.展开更多
Green-revertible albino is a novel type of chlorophyll deficiency in rice （Oryza sativa L.）, which is helpful for further research in chlorophyll synthesis and chloroplast development to illuminate their molecular m...Green-revertible albino is a novel type of chlorophyll deficiency in rice （Oryza sativa L.）, which is helpful for further research in chlorophyll synthesis and chloroplast development to illuminate their molecular mechanism. In the previous study, we had reported a single recessive gene, gra（t）, controlling this trait on the long arm of chromosome 2. In this paper, we mapped the gra（t） gene using 1,936 recessive individuals with albino phenotype in the F2 population derived from the cross between themo-photoperiod-sensitive genic male-sterile （T/PGMS） line Pei＇ai 64S and the spontaneous mutant Qiufeng M. Eventually, it was located to a confined region of 42.4 kb flanked by two microsatellite markers RM2-97 and RM13553. Based on the annotation results of RiceGAAS system, 11 open reading frames （ORFs） were predicted in this region. Among them, ORF6 was the most possible gene related to chloroplast development, which encoded the chloroplast protein synthesis elongation factor Tu in rice. Therefore, we designated it as the candidate gene of gra（t）. Sequence analysis indicated that only one base substitution C to T occurred in the coding region, which caused a missense mutation （Thr to Ile） in gra（t） mutant. These results are very valuable for further study on gra（t） gene.展开更多
Rice with low glutelin content is suitable as functional food for patients affected with diabetes and kidney failure. The fine mapping of the gene(s) responsible for low glutelin content will provide information regar...Rice with low glutelin content is suitable as functional food for patients affected with diabetes and kidney failure. The fine mapping of the gene(s) responsible for low glutelin content will provide information regarding the distribution of glutelin related genes in rice genome and will generate markers for the selection of low glutelin rice varieties. Following an SDS-PAGE screen of rice germplasm from Taihu Valley of China, Japonica selection W3660 is identified to be a novel mutant characterized with low glutelin content. For fine mapping the mutant gene for low glutelin content, F2 and F3 populations were derived from a cross between W3660 and Jingrennuo. SDS-PAGE analysis of the total endosperm protein showed that the low glutelin content trait was controlled by a single dominant nuclear gene. Genetic mapping, using SSRs, located this gene to chromosome 2, in the region between SSR2-001/SSR2-004 and RM1358. The dis- tances of the two markers to the target gene were 1.1 cM and 3.8 cM respectively. By semi-quantitative RT-PCR analysis, the transcripts of GluB4/GluB5 genes located within the region do not change. However, GluB5 gene located proximal to SSR2-001/SSR2-004 was specifically reduced. SSR profiles of seven Japonica varieties were compared with that of W3660 for loci in the relevant genetic region. The markers SSR2-004 and RM1358 were used for marker- assisted selection. The selection efficiencies of SSR2-004 and RM1358 were 96.8% and 92.7% respectively. This provides a standard starting point for the breeding of low glutelin content rice varieties in China.展开更多
A thermo-insensitive pale green leaf mutant （pgl2） was isolated from T-DNA inserted transgenic lines of rice （Oryza sativa L. subsp, japonica cv. Nipponbare）. Genetic analysis indicated that the phenotype was caus...A thermo-insensitive pale green leaf mutant （pgl2） was isolated from T-DNA inserted transgenic lines of rice （Oryza sativa L. subsp, japonica cv. Nipponbare）. Genetic analysis indicated that the phenotype was caused by a recessive mutation in a single nuclear-encoded gene. To map the PGL2gene, an F2 population was constructed by crossing the mutant with Longtefu （Oryza sativa L. subsp, indica）. The PGL2 locus was roughly linked to SSR marker RM331 on chromosome 8. To finely map the gene, 14 new InDel markers were developed around the marker, and PGL2 was further mapped to a 2.37 Mb centromeric region. Analysis on chlorophyll contents of leaves showed that there was no obvious difference between the mutant and the wild type in total chlorophyll （Chl） content, while the ratio of Chl a / Chl b in the mutant was only about 1, which was distinctly lower than that in the wild type, suggesting that the PGL2 gene was related to the conversion between Chl a and Chl b. Moreover, the method of primer design around the centromeric region was discussed, which would provide insight into fine mapping of the functional genes in plant centromeres.展开更多
Seven residual heterozygous lines （RHLs） displaying different genotypic compositions in the genomic region covering probable locations of C （Chromogen for anthocyanin） gene on the short arm of rice chromosome 6 we...Seven residual heterozygous lines （RHLs） displaying different genotypic compositions in the genomic region covering probable locations of C （Chromogen for anthocyanin） gene on the short arm of rice chromosome 6 were selected from the progenies of the indica cross Zhenshan 97B/Milyang 46. Seeds were harvested from each of the seven plants, and the resultant F2：3 populations were used for fine mapping of C gene. It was shown in the populations that the apiculus coloration matched to basal leaf sheath coloration in each plant. By relating the coloration performances of the populations with the genotypic compositions of the RHLs, the C locus was located between rice SSR markers RM314 and RM253. By using a total of 1279 F2：3 individuals from two populations showing coloration segregation, the C locus was then located between RM111 and RM253, with genetic distances of 0.7 cM to RM111 and 0.4 cM to RM253. Twenty-two recombinants found in the two populations were assayed with seven more markers located between RM111 and RM253, including six SSR markers and one marker for the C gene candidate, OsCl. The C locus was delimited to a 59.3-kb region in which OsC1 was located.展开更多
Glabrous rice exhibits glabrous leaves and hulls because neither of these structures have trichomes on their surfaces. Glabrous rice varieties have become an important germplasm resource in the rice industry because t...Glabrous rice exhibits glabrous leaves and hulls because neither of these structures have trichomes on their surfaces. Glabrous rice varieties have become an important germplasm resource in the rice industry because they have considerable packaging efficiency and can reduce skin itching and dust during harvesting, drying, and packing （Shim et al., 2012; Zhang et al., 2012）.展开更多
To fine map the previously detected quantitative trait loci （QTLs） affecting milk production traits on bovine chromosome 6 （BTA6）, 15 microsatellite markers situated within an interval of 14.3 cM spanning from BMS...To fine map the previously detected quantitative trait loci （QTLs） affecting milk production traits on bovine chromosome 6 （BTA6）, 15 microsatellite markers situated within an interval of 14.3 cM spanning from BMS690 to BM4528 were selected and 918 daughters of 8 sires were genotyped. Two mapping approaches, haplotype sharing based LD mapping and single marker regression mapping, were used to analyze the data. Both approaches revealed a quantitative trait locus （QTL） with significant effects on milk yield, fat yield and protein yield located in the segment flanked by markers BMS483 and MNB209, which spans a genetic distance of 0.6 cM and a physical distance of 1.5 Mb. In addition, the single marker regression mapping also revealed a QTL affecting fat percentage and protein percentage at marker DIK2291. Our fine mapping work will facilitate the cloning of candidate genes underlying the QTLs for milk production traits.展开更多
The major storage substance in rice endosperm is starch, which accounts for 80% of dry matter weight. In this study, rice mutant flo7, selected from the progeny of Nipponbare＇s tissue culture, displayed floury and op...The major storage substance in rice endosperm is starch, which accounts for 80% of dry matter weight. In this study, rice mutant flo7, selected from the progeny of Nipponbare＇s tissue culture, displayed floury and opaque endosperm. Compared with its corresponding wild type （WT） Nipponbare, the mutant rio7 produced longer, narrower, thinner and lighter grains. The levels of glucose, fructose and sucrose in the mutant flo7 endosperm were higher than those in the WT endosperm, whereas the protein content was not affected. With respect to both amylose content and gel consistency, the mutant flo7 was lower than WT, but its alkali value was higher. Scanning electron microscopic examinations showed that the endosperm of the mutant flo7 contained irregular, loosely packed and compound starch granules. Genetic analysis indicated that the mutant phenotype was determined by a single recessive nuclear gene The flo7 locus was mapped to a region on the long arm of chromosome 12, within a 95.1 kb interval defined by the markers C2-11 and C5-15. There are 13 open reading frames in the mapping interval. Transcription profiling of the developing grains showed that a number of genes involved in starch synthesis were affected differently in the mutant flo7.展开更多
Soybean mosaic virus(SMV) affects seed quality and production of soybean(Glycine max(L.) Merr.) worldwide.SC18 is one of the dominant SMV strains in South China,and accession Zhonghuang 24 displayed resistance to SC18...Soybean mosaic virus(SMV) affects seed quality and production of soybean(Glycine max(L.) Merr.) worldwide.SC18 is one of the dominant SMV strains in South China,and accession Zhonghuang 24 displayed resistance to SC18.The F_(1),F_(2) and 168 F_(11) recombinant inbred lines(RILs) population derived from a hybridization between Zhonghuang 24(resistant,R) and Huaxia 3(susceptible,S) were used in this study.According to the segregation ratios of the F_(2) generation(3 R:1 S) and the recombinant inbred lines(RILs) population(1 R:1 S),one dominant locus may regulate the resistance to SC18 in Zhonghuang 24.By using composite interval mapping(CIM),Rsc18 was mapped to a 415.357-kb region on chromosome 13.Three candidate genes,including one NBS-LRR type gene and two serine/threonine protein type genes,were identified according to the genetic annotations,which may be related to the resistance to SC18.The q RT-PCR demonstrated that these genes were up-regulated in the R genotype compared to the control.In conclusion,the findings of this research enhanced the understanding about the R genes at the Rsc18 locus.Moreover,our results will provide insights for designing molecular markers to improve marker-assisted selection and developing new varieties with resistance to SC18.展开更多
Rice is one of the most consumed staple food plants around the world, and its plant architecture is very important to improve the grain yield （Zhang et al., 2008）. Plant height, leaf angle, tiller number and angle, ...Rice is one of the most consumed staple food plants around the world, and its plant architecture is very important to improve the grain yield （Zhang et al., 2008）. Plant height, leaf angle, tiller number and angle, and uniformity of panicle layer all can have strong effects on grain yield （Wang and Li, 2008）. During the long history of domestication, rice has been selected to develop uniform tiller height architecture that ensures panicle layer uniformity and ease of harvesting （Ma et al., 2009）, and is largely determined by the synchronic culm elongation.展开更多
Rice panicle is the sink organ where assimilation product accumulates,and its morphology determines the rice yield.Panicle length has been suggested as a yield-related trait,but the genetic factor for its control is s...Rice panicle is the sink organ where assimilation product accumulates,and its morphology determines the rice yield.Panicle length has been suggested as a yield-related trait,but the genetic factor for its control is still limited.In this study,we carried out fine-mapping of qPL8,a QTL identified for panicle length in our previous work.Near isogenic line(NIL)with qPL8 exhibited elongated panicle without obvious effect on other panicle elements.With five key recombinants from NIL population,the locus was finally narrowed down to a 278-kb region,where 44 genes are annotated.By comparing the genomic sequence of two parents,17 genes were identified with SNPs or InDels variations in the coding region.Expression analysis showed that eight genes were up-regulated in the NIL with qPL8.Considering both the coding variation and expression status,several candidate genes for the locus were identified,and OsMADS37 was raised as the most possible candidate.Interestingly,an expression QTL(eQTL)also resides in the locus,leading to a cluster of gene expression variation in the region.This study will facilitate the application of qPL8 locus in rice breeding for yield potential.展开更多
Our previous studies demonstrated that the region around markers BMS470 and BMS1242 on BTA6 showed a linkage to 305-d milk yield and composition traits in the Chinese Holstein population. We herein focused on such nar...Our previous studies demonstrated that the region around markers BMS470 and BMS1242 on BTA6 showed a linkage to 305-d milk yield and composition traits in the Chinese Holstein population. We herein focused on such narrow region to fine map milk production QTLs with 15 SNPs across 25 Mb with each SNP in 1 Mb within most regions in a Chinese Holstein population with daughter design. 1 449 Holstein cows and 11 sires were genotyped for such SNPs by using TaqMan probe and RFLP assays. Multipoint linkage analysis across family revealed a QTL affecting milk yield between PPARGC1A C4075T and SLC34A2 T1713C. Meanwhile, within family analysis found three milk yield QTLs （two in CR T60984131G-CEP135 C501T and one in PDLIM5 A106C-OPN T3907, a fat yield QTLin UGDH T1670C-CR T60984131G region, and two protein yield QTLs in TBC1D1 G501C-UGDH T1670C and PPARGC1A C4075T-SLC34A2 T1713C, respectively. Associations between aforementioned significant SNP markers and milk production traits were further implemented. We found significant associations of PPARGC1A C4075T, SLC34A2 T1713C with milk yield （P0.05, P0.01, P0.01）, UGDH T1670C, and CR T60984131G with fat yield （P0.01, P0.01）, and PPARGC1A C4075T, SLC34A2 T1713C, UGDH T1670C and OPN T3907 with protein yield （P0.01, P0.01, P0.01, P0.01）. Our findings implied that QTLs affecting milk production traits on BTA6 were pleictropism or multigenic effect and PPARGC1A and OPN may be the causal mutations behind milk production QTLs on BTA6 in the Chinese Holstein population.展开更多
Heading date(flowering time)determines the adaptability of cultivars to different environments.We report the fine mapping and candidate gene analysis of qHD1b,a quantitative trait locus(QTL)responsible for early flowe...Heading date(flowering time)determines the adaptability of cultivars to different environments.We report the fine mapping and candidate gene analysis of qHD1b,a quantitative trait locus(QTL)responsible for early flowering that was derived from common wild rice(O.rufipogon)under both short-day and longday conditions.The introgression line IL7391,which carried segments from common wild rice in a Zhonghui 8015(ZH8015)background,exhibited early heading compared to the background and was crossed with ZH8015 to generate BC_(5)F_(2:3) families for QTL analysis.This enabled the identification of two heading-date QTL,named qHD1b and qHD7,of which the first was selected for further research.High-resolution linkage analysis was performed in BC_(5)F_(4:5) and BC_(5)F_(6) populations,and the location of qHD1b was confined to a 112.7-kb interval containing 17 predicted genes.Five of these genes contained polymorphisms in the promoter or coding regions and were thus considered as candidates.Expression analysis revealed a positive association between LOC_Os01g11940 expression and early heading.This locus was annotated as OsFTL1,which encodes an ortholog of Arabidopsis Flowering Locus T and was the most likely candidate gene for qHD1b.Our study revealed that qHD1b acts as a floral activator that promotes flowering by up-regulating Ehd1,Hd3a,RFT1,OsMADS14,and OsMADS15 under both shortday and long-day conditions.Field experiments showed that qHD1b affected several yield-related agronomic traits including 1000-grain weight and grain length.qHD1b could be useful for marker-assisted selection and breeding of early-maturing cultivars.展开更多
A rice heading-date-related mutant was isolated from a ^60Co-y-ray-induced mutation pool of Zhejing 22, a conventional japonica cultivar in Zhejiang Province, China. The mutant was characterized by a delayed heading d...A rice heading-date-related mutant was isolated from a ^60Co-y-ray-induced mutation pool of Zhejing 22, a conventional japonica cultivar in Zhejiang Province, China. The mutant was characterized by a delayed heading date of almost 20 d longer than the wild type plant. Genetic analysis revealed that the mutation was controlled by a single nuclear-encoded recessive gene that was designed as HD（t） （heading date tentatively）. To isolate the HD（t） gene, a map-based cloning approach was employed using 479 F2 mutant individual plants derived from the cross between the hd（t） mutant （japonica） x Zhenshan 97 （indica）. Finally, the HD（t） gene was mapped to an approximate 53 kb region between the insertion and deletion （InDel） markers of 10-61W and 10-66W on chromosome 10. According to the genome sequence of Nipponbare, the target region contains 11 annotated genes. It is helpful for future cloning of HD（t） gene based on this fine mapping results.展开更多
Thousand-kernel weight(TKW)is a measure of grain weight,a target of wheat breeding.The object of this study was to fine-map a stable quantitative trait loci(QTL)for TKW and identify its candidate gene in a recombinant...Thousand-kernel weight(TKW)is a measure of grain weight,a target of wheat breeding.The object of this study was to fine-map a stable quantitative trait loci(QTL)for TKW and identify its candidate gene in a recombinant inbred line(RIL)population derived from the cross of Kenong 9204(KN9204)and Jing411(J411).On a high-density genetic linkage map,24,26 and 25 QTL were associated with TKW,kernel length(KL),and kernel width(KW),respectively.A major and stable QTL,QTkw-2D,was mapped to an8.3 cM interval on chromosome arm 2DL.By saturation of polymorphic markers in its target region,QTkw-2D was confined to a 9.13 Mb physical interval using a secondary mapping population derived from a residually heterozygous line(F6:7).This interval was further narrowed to 2.52 Mb using QTkw-2D near-isogenic lines(NILs).NILs~(KN9204)had higher fresh and dry weights than NILsJ411at various grain-filling stages.The TKW and KW of NILs~(KN9204)were much higher than those of NILsJ411in field trials.By comparison of both DNA sequence and expression between KN9204 and J411,TraesCS2D02G460300.1(TraesKN2D01HG49350)was assigned as a candidate gene for QTkw-2D.This was confirmed by RNA sequencing(RNA-seq)of QTkw-2D NILs.These results provide the basis of map-based cloning of QTkw-2D,and DNA markers linked to the candidate gene may be used in marker-assisted selection.展开更多
基金financially supported by National Natural Science Foundation of China(32301800,32301923 and 32072053)Wheat Industrial Technology System of Shandong Province(SDAIT-01-01)Key Research and Development Project of Shandong Province(2022LZG002-4,2023LZGC009-4-4).
文摘Powdery mildew negatively impacts wheat yield and quality.Emmer wheat(Triticum dicoccum),an ancestral species of common wheat,is a gene donor for wheat improvement.Cultivated emmer accession H1-707 exhibited all-stage resistance to powdery mildew over consecutive years.Genetic analysis of H1-707 at the seedling stage revealed a dominant monogenic inheritance pattern,and the underlying gene was designated Pm71.By employing bulked segregant exome sequencing(BSE-Seq)and using 2000 F2:3 families,Pm71 was fine mapped to a 336-kb interval on chromosome arm 6AS by referencing to the durum cv.Svevo RefSeq 1.0.Collinearity analysis revealed high homology in the candidate interval between Svevo and six Triticum species.Among six high-confidence genes annotated within this interval,TRITD6Av1G005050 encoding a GDSL esterase/lipase was identified as a key candidate for Pm71.
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 Key Research and Development Project of China(2022YFD1200700)the Crop Varietal Improvement and Insect Pests Control by Nuclear Radiation,Innovation Program of Chinese Academy of Agricultural Sciences,and the China Agriculture Research System(CARS-03).
文摘Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,je0407,with an 84.34%-89.35%smaller flag leaf angle compared with the wild type.The mutant also had an abnormal lamina joint and no ligule or auricle.Genetic analysis indicated that the ligule was controlled by two recessive genes,which were mapped to chromosomes 2AS and 2DL.The mutant allele on chromosome 2AS was named Tafla1b,and it was fine mapped to a 1 Mb physical interval.The mutant allele on chr.2DL was identified as Taspl8b,a novel allele of TaSPL8 with a missense mutation in the second exon,which was used to develop a cleaved amplified polymorphic sequence marker.F3 and F4 lines derived from crosses between Jing411 and je0407 were genotyped to investigate interactions between the Tafla1b and Taspl8b alleles.Plants with the Tafla1b/Taspl8a genotype had 58.41%-82.76%smaller flag leaf angles,6.4%-24.9%shorter spikes,and a greater spikelet density(0.382 more spikelets per cm)compared with the wild type.Plants with the Tafla1a/Taspl8b genotype had 52.62%-82.24%smaller flag leaf angles and no differences in plant height or spikelet density compared with the wild type.Tafla1b/Taspl8b plants produced erect leaves with an abnormal lamina joint.The two alleles had dosage effects on ligule formation and flag leaf angle,but no significant effect on thousand-grain weight.The mutant alleles provide novel resources for improvement of wheat plant architecture.
基金We thank the Wuhan Major Project of Key Technologies in Biological Breeding and New Variety Cultivation,China(2022021302024852)The Science and Technology Support Project of Rural Vitalization in Hubei Province,China(2022BBA121)+1 种基金the Key Research and Development Project of Hubei Province,China(2021BBA097)The Key Research and Development Project of Hubei Province,China(2021BBA102)。
文摘The application of a male-sterile line is an ideal approach for hybrid seed production in non-heading Chinese cabbage(Brassica rapa ssp.chinensis).However,the molecular mechanisms underlying male sterility in B.rapa are still largely unclear.We previously obtained the natural male sterile line WS24-3 of non-heading Chinese cabbage and located the male sterile locus,Bra2Ms,on the A2 chromosome.Cytological observations revealed that the male sterility of WS24-3 resulted from disruption of the meiosis process during pollen formation.Fine mapping of Bra2Ms delimited the locus within a physical distance of about 129 kb on the A2 chromosome of B.rapa.The Bra039753 gene encodes a plant homeodomain(PHD)-finger protein and is considered a potential candidate gene for Bra2Ms.Bra039753 was significantly downregulated in sterile line WS24-3 compared to the fertile line at the meiotic anther stage.Sequence analysis of Bra039753 identified a 369 bp fragment insertion in the first exon in male sterile plants,which led to an amino acid insertion in the Bra039753 protein.In addition,the 369 bp fragment insertion was found to cosegregate with the male sterility trait.This study identified a novel locus related to male sterility in non-heading Chinese cabbage,and the molecular marker obtained in this study will be beneficial for the marker-assisted selection of excellent sterile lines in non-heading Chinese cabbage and other Brassica crops.
基金supported by the National Natural Science Foundation of China(32072053,32301800,and 32301923)Wheat Industry Technology System of Shandong Province(SDAIT-01-01)the Key R&D Plan of Shandong Province(2022LZG002-4).
文摘In a wheat breeding line XQ-0508 showing consistent resistance to powdery mildew disease,a recessive gene,designated PmXQ-0508,was identified and mapped to a distal region on chromosome arm 2BS.Of three resistance-associated genes in this region,one encoding a protein kinase was selected as the primary candidate for PmXQ-0508.Ten closely linked DNA markers developed in the study could be used for marker-assisted selection for powdery-mildew resistance in breeding programs.
文摘The ast ( anthocyanin spotted testa) mutant, which was induced by carbon ion radiation, was a single recessive gene mutant of Arabidopsis thaliana (L.) Heynh. with spotted pigment in seed coats, and involved in the anthocyanin biosynthesis. To clone the AST gene by map-based cloning strategy, a series of molecular markers were designed according to the SNPs (single nucleotide polymophisms) and insertion/deletion polymophisms in the Arabidopsis database. With these molecular markers, the fine-structure mapping of the AST gene was finished, the AST locus was located in BAC clone T13M11. It was suggested that the AST candidate gene was T13M11. 8 in the T13M11 This gene was 1432 bp long with 6 exons and 5 introns. The putative protein of T13M11. 8 gene was similar to dihydroflavonol 4-reductase (DFR), which was an important enzyme in the anthocyanin biosynthesis pathway.
基金supported by the National High-tech Research and Development Program of China (863 Program) (No. 2006AA100101)the National Science and Technology Support Program (No. 2006BAD01A01-5)+1 种基金Special Program for Rice Scientific Research of Ministry of Agriculture (No. nyhyzx 07-001-006)Super Rice Breeding and Demonstration Program of Ministry of Agriculture, and Jiangsu Selfinnovation Fund for Agricultural Science and Technology (No. CX[08]603).
文摘Green-revertible albino is a novel type of chlorophyll deficiency in rice （Oryza sativa L.）, which is helpful for further research in chlorophyll synthesis and chloroplast development to illuminate their molecular mechanism. In the previous study, we had reported a single recessive gene, gra（t）, controlling this trait on the long arm of chromosome 2. In this paper, we mapped the gra（t） gene using 1,936 recessive individuals with albino phenotype in the F2 population derived from the cross between themo-photoperiod-sensitive genic male-sterile （T/PGMS） line Pei＇ai 64S and the spontaneous mutant Qiufeng M. Eventually, it was located to a confined region of 42.4 kb flanked by two microsatellite markers RM2-97 and RM13553. Based on the annotation results of RiceGAAS system, 11 open reading frames （ORFs） were predicted in this region. Among them, ORF6 was the most possible gene related to chloroplast development, which encoded the chloroplast protein synthesis elongation factor Tu in rice. Therefore, we designated it as the candidate gene of gra（t）. Sequence analysis indicated that only one base substitution C to T occurred in the coding region, which caused a missense mutation （Thr to Ile） in gra（t） mutant. These results are very valuable for further study on gra（t） gene.
基金supported by the grants from Hi-Tech Research and Development Program of China("863"Program,No.2003AA222131,2003AA207020)the National Natural Science Foundation of China(No.30170570)Special Program for gene-transfering(No.JY03-B-07,JY03-A-07-02)
文摘Rice with low glutelin content is suitable as functional food for patients affected with diabetes and kidney failure. The fine mapping of the gene(s) responsible for low glutelin content will provide information regarding the distribution of glutelin related genes in rice genome and will generate markers for the selection of low glutelin rice varieties. Following an SDS-PAGE screen of rice germplasm from Taihu Valley of China, Japonica selection W3660 is identified to be a novel mutant characterized with low glutelin content. For fine mapping the mutant gene for low glutelin content, F2 and F3 populations were derived from a cross between W3660 and Jingrennuo. SDS-PAGE analysis of the total endosperm protein showed that the low glutelin content trait was controlled by a single dominant nuclear gene. Genetic mapping, using SSRs, located this gene to chromosome 2, in the region between SSR2-001/SSR2-004 and RM1358. The dis- tances of the two markers to the target gene were 1.1 cM and 3.8 cM respectively. By semi-quantitative RT-PCR analysis, the transcripts of GluB4/GluB5 genes located within the region do not change. However, GluB5 gene located proximal to SSR2-001/SSR2-004 was specifically reduced. SSR profiles of seven Japonica varieties were compared with that of W3660 for loci in the relevant genetic region. The markers SSR2-004 and RM1358 were used for marker- assisted selection. The selection efficiencies of SSR2-004 and RM1358 were 96.8% and 92.7% respectively. This provides a standard starting point for the breeding of low glutelin content rice varieties in China.
文摘A thermo-insensitive pale green leaf mutant （pgl2） was isolated from T-DNA inserted transgenic lines of rice （Oryza sativa L. subsp, japonica cv. Nipponbare）. Genetic analysis indicated that the phenotype was caused by a recessive mutation in a single nuclear-encoded gene. To map the PGL2gene, an F2 population was constructed by crossing the mutant with Longtefu （Oryza sativa L. subsp, indica）. The PGL2 locus was roughly linked to SSR marker RM331 on chromosome 8. To finely map the gene, 14 new InDel markers were developed around the marker, and PGL2 was further mapped to a 2.37 Mb centromeric region. Analysis on chlorophyll contents of leaves showed that there was no obvious difference between the mutant and the wild type in total chlorophyll （Chl） content, while the ratio of Chl a / Chl b in the mutant was only about 1, which was distinctly lower than that in the wild type, suggesting that the PGL2 gene was related to the conversion between Chl a and Chl b. Moreover, the method of primer design around the centromeric region was discussed, which would provide insight into fine mapping of the functional genes in plant centromeres.
基金This work was supported by the Chinese 863 Program(Grant No.2006AA10Z1E8)the Super Rice Program of the Chinese Ministry of Agriculture(Grant No.200606)the Natural Science Foundation of Zhejiang Province(Grant No.Y304446).
文摘Seven residual heterozygous lines （RHLs） displaying different genotypic compositions in the genomic region covering probable locations of C （Chromogen for anthocyanin） gene on the short arm of rice chromosome 6 were selected from the progenies of the indica cross Zhenshan 97B/Milyang 46. Seeds were harvested from each of the seven plants, and the resultant F2：3 populations were used for fine mapping of C gene. It was shown in the populations that the apiculus coloration matched to basal leaf sheath coloration in each plant. By relating the coloration performances of the populations with the genotypic compositions of the RHLs, the C locus was located between rice SSR markers RM314 and RM253. By using a total of 1279 F2：3 individuals from two populations showing coloration segregation, the C locus was then located between RM111 and RM253, with genetic distances of 0.7 cM to RM111 and 0.4 cM to RM253. Twenty-two recombinants found in the two populations were assayed with seven more markers located between RM111 and RM253, including six SSR markers and one marker for the C gene candidate, OsCl. The C locus was delimited to a 59.3-kb region in which OsC1 was located.
基金supported by the grants from the National Natural Science Foundation of China(Nos.31025017 and30971763)the National High-tech R&D Program of China(863 Program)(No.2012AA101101)
文摘Glabrous rice exhibits glabrous leaves and hulls because neither of these structures have trichomes on their surfaces. Glabrous rice varieties have become an important germplasm resource in the rice industry because they have considerable packaging efficiency and can reduce skin itching and dust during harvesting, drying, and packing （Shim et al., 2012; Zhang et al., 2012）.
基金supported by the National Key Basic Research Program of China (No. 2006CB102104)
文摘To fine map the previously detected quantitative trait loci （QTLs） affecting milk production traits on bovine chromosome 6 （BTA6）, 15 microsatellite markers situated within an interval of 14.3 cM spanning from BMS690 to BM4528 were selected and 918 daughters of 8 sires were genotyped. Two mapping approaches, haplotype sharing based LD mapping and single marker regression mapping, were used to analyze the data. Both approaches revealed a quantitative trait locus （QTL） with significant effects on milk yield, fat yield and protein yield located in the segment flanked by markers BMS483 and MNB209, which spans a genetic distance of 0.6 cM and a physical distance of 1.5 Mb. In addition, the single marker regression mapping also revealed a QTL affecting fat percentage and protein percentage at marker DIK2291. Our fine mapping work will facilitate the cloning of candidate genes underlying the QTLs for milk production traits.
基金supported by China National Natural Science Foundation (Grant Nos. 31471472 and 31301303)Natural Science Foundation of Zhejiang Province,China (Grant Nos. LY13C130003 and LY14C130012)
文摘The major storage substance in rice endosperm is starch, which accounts for 80% of dry matter weight. In this study, rice mutant flo7, selected from the progeny of Nipponbare＇s tissue culture, displayed floury and opaque endosperm. Compared with its corresponding wild type （WT） Nipponbare, the mutant rio7 produced longer, narrower, thinner and lighter grains. The levels of glucose, fructose and sucrose in the mutant flo7 endosperm were higher than those in the WT endosperm, whereas the protein content was not affected. With respect to both amylose content and gel consistency, the mutant flo7 was lower than WT, but its alkali value was higher. Scanning electron microscopic examinations showed that the endosperm of the mutant flo7 contained irregular, loosely packed and compound starch granules. Genetic analysis indicated that the mutant phenotype was determined by a single recessive nuclear gene The flo7 locus was mapped to a region on the long arm of chromosome 12, within a 95.1 kb interval defined by the markers C2-11 and C5-15. There are 13 open reading frames in the mapping interval. Transcription profiling of the developing grains showed that a number of genes involved in starch synthesis were affected differently in the mutant flo7.
基金supported by the projects of the Key-Areas Research and Development Program of Guangdong Province, China (2020B020220008)the China Agriculture Research System of MOF and MARA (CARS-04-PSO9)+2 种基金the Major Project of New Varieties Cultivation of Genetically Modified Varieties, China (2016ZX08004002-007)the National Key R&D Program of China (2017FYD0101500)the National Natural Science Foundation of China (31971966)。
文摘Soybean mosaic virus(SMV) affects seed quality and production of soybean(Glycine max(L.) Merr.) worldwide.SC18 is one of the dominant SMV strains in South China,and accession Zhonghuang 24 displayed resistance to SC18.The F_(1),F_(2) and 168 F_(11) recombinant inbred lines(RILs) population derived from a hybridization between Zhonghuang 24(resistant,R) and Huaxia 3(susceptible,S) were used in this study.According to the segregation ratios of the F_(2) generation(3 R:1 S) and the recombinant inbred lines(RILs) population(1 R:1 S),one dominant locus may regulate the resistance to SC18 in Zhonghuang 24.By using composite interval mapping(CIM),Rsc18 was mapped to a 415.357-kb region on chromosome 13.Three candidate genes,including one NBS-LRR type gene and two serine/threonine protein type genes,were identified according to the genetic annotations,which may be related to the resistance to SC18.The q RT-PCR demonstrated that these genes were up-regulated in the R genotype compared to the control.In conclusion,the findings of this research enhanced the understanding about the R genes at the Rsc18 locus.Moreover,our results will provide insights for designing molecular markers to improve marker-assisted selection and developing new varieties with resistance to SC18.
基金supported by funds from the National Transgenic Major Program Grants(No.2009ZX08009-022B)
文摘Rice is one of the most consumed staple food plants around the world, and its plant architecture is very important to improve the grain yield （Zhang et al., 2008）. Plant height, leaf angle, tiller number and angle, and uniformity of panicle layer all can have strong effects on grain yield （Wang and Li, 2008）. During the long history of domestication, rice has been selected to develop uniform tiller height architecture that ensures panicle layer uniformity and ease of harvesting （Ma et al., 2009）, and is largely determined by the synchronic culm elongation.
基金This work was supported by grants from the National Natural Science Foundation of China(31871217 and 32072037)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(20KJA210002)the Key Research and Development Program of Jiangsu Province(BE2018357).
文摘Rice panicle is the sink organ where assimilation product accumulates,and its morphology determines the rice yield.Panicle length has been suggested as a yield-related trait,but the genetic factor for its control is still limited.In this study,we carried out fine-mapping of qPL8,a QTL identified for panicle length in our previous work.Near isogenic line(NIL)with qPL8 exhibited elongated panicle without obvious effect on other panicle elements.With five key recombinants from NIL population,the locus was finally narrowed down to a 278-kb region,where 44 genes are annotated.By comparing the genomic sequence of two parents,17 genes were identified with SNPs or InDels variations in the coding region.Expression analysis showed that eight genes were up-regulated in the NIL with qPL8.Considering both the coding variation and expression status,several candidate genes for the locus were identified,and OsMADS37 was raised as the most possible candidate.Interestingly,an expression QTL(eQTL)also resides in the locus,leading to a cluster of gene expression variation in the region.This study will facilitate the application of qPL8 locus in rice breeding for yield potential.
基金supported by the National 948 Project of China (2006-G48)the National Key Technologies R&D Program of China (2006BAD04A01)+1 种基金the Key Development of New Transgenic Breeds Program of China (2009ZX08009-156B)the National Natural Science Foundation of China (31072016)
文摘Our previous studies demonstrated that the region around markers BMS470 and BMS1242 on BTA6 showed a linkage to 305-d milk yield and composition traits in the Chinese Holstein population. We herein focused on such narrow region to fine map milk production QTLs with 15 SNPs across 25 Mb with each SNP in 1 Mb within most regions in a Chinese Holstein population with daughter design. 1 449 Holstein cows and 11 sires were genotyped for such SNPs by using TaqMan probe and RFLP assays. Multipoint linkage analysis across family revealed a QTL affecting milk yield between PPARGC1A C4075T and SLC34A2 T1713C. Meanwhile, within family analysis found three milk yield QTLs （two in CR T60984131G-CEP135 C501T and one in PDLIM5 A106C-OPN T3907, a fat yield QTLin UGDH T1670C-CR T60984131G region, and two protein yield QTLs in TBC1D1 G501C-UGDH T1670C and PPARGC1A C4075T-SLC34A2 T1713C, respectively. Associations between aforementioned significant SNP markers and milk production traits were further implemented. We found significant associations of PPARGC1A C4075T, SLC34A2 T1713C with milk yield （P0.05, P0.01, P0.01）, UGDH T1670C, and CR T60984131G with fat yield （P0.01, P0.01）, and PPARGC1A C4075T, SLC34A2 T1713C, UGDH T1670C and OPN T3907 with protein yield （P0.01, P0.01, P0.01, P0.01）. Our findings implied that QTLs affecting milk production traits on BTA6 were pleictropism or multigenic effect and PPARGC1A and OPN may be the causal mutations behind milk production QTLs on BTA6 in the Chinese Holstein population.
基金supported by the National Natural Science Foundation of China(31871604,32071996,and 31961143016)the National Key Research and Development Program of China(2020YFE0202300)+1 种基金the Fundamental Research Funds of Central Public Welfare Research Institutions(CPSIBRFCNRRI-202102)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP2013-CNRRI).
文摘Heading date(flowering time)determines the adaptability of cultivars to different environments.We report the fine mapping and candidate gene analysis of qHD1b,a quantitative trait locus(QTL)responsible for early flowering that was derived from common wild rice(O.rufipogon)under both short-day and longday conditions.The introgression line IL7391,which carried segments from common wild rice in a Zhonghui 8015(ZH8015)background,exhibited early heading compared to the background and was crossed with ZH8015 to generate BC_(5)F_(2:3) families for QTL analysis.This enabled the identification of two heading-date QTL,named qHD1b and qHD7,of which the first was selected for further research.High-resolution linkage analysis was performed in BC_(5)F_(4:5) and BC_(5)F_(6) populations,and the location of qHD1b was confined to a 112.7-kb interval containing 17 predicted genes.Five of these genes contained polymorphisms in the promoter or coding regions and were thus considered as candidates.Expression analysis revealed a positive association between LOC_Os01g11940 expression and early heading.This locus was annotated as OsFTL1,which encodes an ortholog of Arabidopsis Flowering Locus T and was the most likely candidate gene for qHD1b.Our study revealed that qHD1b acts as a floral activator that promotes flowering by up-regulating Ehd1,Hd3a,RFT1,OsMADS14,and OsMADS15 under both shortday and long-day conditions.Field experiments showed that qHD1b affected several yield-related agronomic traits including 1000-grain weight and grain length.qHD1b could be useful for marker-assisted selection and breeding of early-maturing cultivars.
基金supported by the Chinese Ministry of Agriculture(Grant Nos.200803034 and 2011ZX08001001)the Zhejiang Provincial and the National Natural Science Foundation of China(Grant Nos.Y3080361 and 31071207)+2 种基金the Science and Technology Department of Zhejiang Province,China(Grant No.2004C12020)the Special Fund for Agro-scientific Research in the Public Interest(Grant No.201103007)the Special Fund of Zhejiang Academy of Agricultural Science,China
文摘A rice heading-date-related mutant was isolated from a ^60Co-y-ray-induced mutation pool of Zhejing 22, a conventional japonica cultivar in Zhejiang Province, China. The mutant was characterized by a delayed heading date of almost 20 d longer than the wild type plant. Genetic analysis revealed that the mutation was controlled by a single nuclear-encoded recessive gene that was designed as HD（t） （heading date tentatively）. To isolate the HD（t） gene, a map-based cloning approach was employed using 479 F2 mutant individual plants derived from the cross between the hd（t） mutant （japonica） x Zhenshan 97 （indica）. Finally, the HD（t） gene was mapped to an approximate 53 kb region between the insertion and deletion （InDel） markers of 10-61W and 10-66W on chromosome 10. According to the genome sequence of Nipponbare, the target region contains 11 annotated genes. It is helpful for future cloning of HD（t） gene based on this fine mapping results.
基金jointly supported by the National Natural Science Foundation of China(32272056,U22A6009,31671673,and 31871612)Hebei Natural Science Foundation(C2021205013,C2022204202)+1 种基金Talents Program of Hebei Agricultural University in China(YJ2021016)China Agriculture Research System of MOF and MARA(CARS-03)。
文摘Thousand-kernel weight(TKW)is a measure of grain weight,a target of wheat breeding.The object of this study was to fine-map a stable quantitative trait loci(QTL)for TKW and identify its candidate gene in a recombinant inbred line(RIL)population derived from the cross of Kenong 9204(KN9204)and Jing411(J411).On a high-density genetic linkage map,24,26 and 25 QTL were associated with TKW,kernel length(KL),and kernel width(KW),respectively.A major and stable QTL,QTkw-2D,was mapped to an8.3 cM interval on chromosome arm 2DL.By saturation of polymorphic markers in its target region,QTkw-2D was confined to a 9.13 Mb physical interval using a secondary mapping population derived from a residually heterozygous line(F6:7).This interval was further narrowed to 2.52 Mb using QTkw-2D near-isogenic lines(NILs).NILs~(KN9204)had higher fresh and dry weights than NILsJ411at various grain-filling stages.The TKW and KW of NILs~(KN9204)were much higher than those of NILsJ411in field trials.By comparison of both DNA sequence and expression between KN9204 and J411,TraesCS2D02G460300.1(TraesKN2D01HG49350)was assigned as a candidate gene for QTkw-2D.This was confirmed by RNA sequencing(RNA-seq)of QTkw-2D NILs.These results provide the basis of map-based cloning of QTkw-2D,and DNA markers linked to the candidate gene may be used in marker-assisted selection.
