Grape berry shape is an important agricultural trait.Clarifying its genetic basis is significant for cultivating grape varieties that meet market demands.However,the current study by forward genetics has not achieved ...Grape berry shape is an important agricultural trait.Clarifying its genetic basis is significant for cultivating grape varieties that meet market demands.However,the current study by forward genetics has not achieved in-depth results.Here,a high-density map was constructed to identify quantitative trait loci(QTLs)for berry shape.A total of 358709 polymorphic SNPs were obtained using whole-genome resequencing(WGS)based on 208 F2 individuals derived from round grape‘E42-6’and oblong grape‘Rizamat’.The 1635.65 cM high-density map was divided into 19 linkage groups with an average distance of 0.37 cM.Using this map,three significant QTLs for fruit shape index(ShI:ratio of berry length to berry width)identified over three years were mapped onto LG4 and LG5,including one stable QTL on Chr5 with the genomic region of 0.47–1.94 Mb.Combining with gene annotation and expression patterns based on RNA-seq data from two contrasting F2 individuals with round and oblong berry(their average ShI was 1.89 and 1.10,respectively)at four developmental stages,four candidate genes were selected from the above QTLs.They were mainly involved in DNA replication,cell wall modification,and phytohormone biosynthesis.Further analysis of RNA-seq data revealed that several important phytohormone synthesis and metabolic pathways were enriched based on differentially expressed genes(DEGs),which was consistent with the results of QTL mapping for genes related to plant hormone biosynthesis in the F2 population.Furthermore,a comparison of plant hormone content showed that there were significant differences in IAA and tZ content between the two contrasting F2 individuals at different developmental stages.Our findings provide molecular insights into the genetic variation in grape berry shape.Stable QTLs and their tightly linked markers offer the possibility of marker-assisted selection to accelerate berry shape breeding.展开更多
A large amount of genome-wide association study(GWAS)panels together with quantitative-trait locus(QTL)information associated with breeding-targeted traits have been described in wheat(Triticum aestivum L.).However,th...A large amount of genome-wide association study(GWAS)panels together with quantitative-trait locus(QTL)information associated with breeding-targeted traits have been described in wheat(Triticum aestivum L.).However,the application of mapping results from a GWAS panel to conventional wheat breeding remains a challenge.In this study,we first report a general genetic map which was constructed from 44 published linkage maps.It permits the estimation of genetic distances between any two genetic loci with physical map positions,thereby unifying the linkage relationships between QTL,genes,and genomic markers from multiple genetic populations.Second,we describe QTL mapping in a wheat GWAS panel of 688 accessions,identifying 77 QTL associated with 12 yield and grain-quality traits.Because these QTL have known physical map positions,they could be mapped onto the general map.Finally,we present a design approach to wheat breeding by using known QTL information and computer simulation.Potential crosses between parents in the GWAS panel may be evaluated by the relative frequency of the target genotype,trait correlations in simulated progeny populations,and genetic gain of selected progenies.It is possible to simultaneously improve yield and grain quality by suitable parental selection,progeny population size,and progeny selection scheme.Applying the design approach will allow identifying the most promising crosses and selection schemes in advance of the field experiment,increasing predictability and efficiency in wheat breeding.展开更多
Owing to the limitation of a large genome size(~13 Gb),the genetic and gene mapping studies on faba bean(Vicia faba L.)are lagging far behind those for other legumes.In this study,we selected three purified faba bean ...Owing to the limitation of a large genome size(~13 Gb),the genetic and gene mapping studies on faba bean(Vicia faba L.)are lagging far behind those for other legumes.In this study,we selected three purified faba bean lines(Yundou 8137,H0003712,and H000572)as parents and constructed two F2 populations.These two F2 populations,namely 167 F2 plants in Pop1(Yundou 8137×H0003712)and 204 F2 plants in Pop2(H000572×Yundou 8137),were genotyped using a targeted next-generation sequencing(TNGS)genotyping platform,and two high-density single nucleotide polymorphisms(SNP)genetic linkage maps of faba bean were constructed.The map constructed from Pop1 contained 5103 SNPs with a length of 1333.31 cM and an average marker density of 0.26 cM.The map constructed from Pop2 contained 1904 SNPs with a greater length of 1610.61 cM.In these two F2 populations,QTL mapping identified 98 QTLs for 14 agronomic traits related to the flowers,pods,plant types and grains.The two maps were then merged into an integrated genetic linkage map containing 6895 SNPs,with a length of 3324.48 cM.These results not only lay the foundation for fine mapping and map-based cloning of related genes,but can also accelerate the molecular marker-assisted breeding of faba bean.展开更多
Soybean is a major crop in the world, and it is a main source of plant proteins and oil. A lot of soybean genetic maps and physical maps have been constructed, but there are no integrated map between soybean physical ...Soybean is a major crop in the world, and it is a main source of plant proteins and oil. A lot of soybean genetic maps and physical maps have been constructed, but there are no integrated map between soybean physical map and genetic map. In this study, soybean genome sequence data, released by JGI (US Department of Energy's Joint Genome Institute), had been downloaded. With the software Blast 2.2.16, a total of 161 super sequences were mapped on the soybean public genetic map to construct an integrated map. The length of these super sequences accounted for 73.08% of all the genome sequence. This integrated map could be used for gene cloning, gene mining, and comparative genome of legume.展开更多
Litchi chinensis Sonn is widely cultivated in subtropical regions and has an important economic value.A high-density genetic map is a valuable tool for mapping quantitative trait loci(QTL)and marker-assisted breeding ...Litchi chinensis Sonn is widely cultivated in subtropical regions and has an important economic value.A high-density genetic map is a valuable tool for mapping quantitative trait loci(QTL)and marker-assisted breeding programs.In this study,a single nucleotide polymorphism(SNP)-based high-density linkage map was constructed by a genotyping-by-sequencing(GBS)protocol using an F1 population of 178 progenies between two commercial litchi cultivars,‘Ziniangxi’(dwarf)and‘Feizixiao’(vigorous).The genetic map consisted of 3027 SNP markers with a total length of 1711.97 cM in 15 linkage groups(LGs)and an average marker distance of 0.57 cM.Based on this high-density linkage map and three years of phenotyping,a total of 37 QTLs were detected for eight dwarf-related traits,including length of new branch(LNB),diameter of new branch(DNB),length of common petiole(LCP),diameter of common petiole(DCP),length of internode(LI),length of single leaf(LSL),width of single leaf(WSL),and plant height(PH).These QTLs could explain 8.0 to 14.7%(mean=9.7%)of the phenotypic variation.Among them,several QTL clusters were observed,particularly on LG04 and LG11,which might show enrichment for genes regulating the dwarf-related traits in litchi.There were 126 candidate genes identified within the QTL regions,55 of which are differentially expressed genes by RNA-seq analysis between‘Ziniangxi’and‘Feizixiao’.These DEGs were found to participate in the regulation of cell development,material transportation,signal transduction,and plant morphogenesis,so they might play important roles in regulating plant dwarf-related traits.The high-density genetic map and QTLs identification related to dwarf traits can provide a valuable genetic resource and a basis for marker-assisted selection and genomic studies of litchi.展开更多
Long-day length and high temperature inhibit sex expression in pumpkin(Cucurbita moschata Duch.),and therefore directly impact the production potential.In this study,female flowering patterns in photoperiod-insensitiv...Long-day length and high temperature inhibit sex expression in pumpkin(Cucurbita moschata Duch.),and therefore directly impact the production potential.In this study,female flowering patterns in photoperiod-insensitive(PPIS)and photoperiod-sensitive(PPS)germplasms differed significantly in a moderately long day and high temperature environment.However,both germplasms exhibited a similar response in short day with either low temperature or high temperature environment.Photoperiod sensitivity led to this difference in sex expression between the germplasms.For the traits of 1st female flowering node(FFFN)and number of female flowers(NFF),high-density linkage map construction and quantitative trait locus(QTL)mapping were performed using SLAF-seq technology and 162 F_(2) individuals generated from PPIS and PPS.In total,4655 SLAFs were selected and mapped on 20 linkage groups(LGs).The total map length was 2502.01 cM with an average interval distance of 0.75 cM.Major QTLs for both FFFN and NFF were detected on LG6 with intervals of 7.89 and 17.67 cM and PVE values of 30.5%and 22.9%,respectively.Further analyses of the major locus for FFFN revealed 73 protein-coding genes.Among them,4 were related to sex expression,photoperiod flowering,and hormone response.An InDel(insertion and deletion)marker partially correlated with FFFN of the F_(2) population was also developed.Our study identified the QTL for the sex expression response to environmental factors using the high-density linkage map.The identified candidate genes and markers will provide useful information about the molecular interaction between the environment and sex expression and for marker-assisted selection of pumpkin environment-insensitive resources.展开更多
General combining abilities (GCAs) are very important in utilization of heterosis in maize breeding. However, its genetic basis is unclear. In the present study, a set of 118 doubled haploid (DH) lines were induce...General combining abilities (GCAs) are very important in utilization of heterosis in maize breeding. However, its genetic basis is unclear. In the present study, a set of 118 doubled haploid (DH) lines were induced from F1 generations produced from the cross between the inbred line Zheng 58 and the inbred line W499 belonging to the Reid subgroup. Using the MaizeSNP50 BeadChip, a high-density genetic map was constructed based on the DH population which included 1 147 bin markers with an average interval length of 2.00 cM. Meanwhile, the DH population was crossed with three testers including W16-5, HD568, and W556, which belong to the Sipingtou subgroup. The GCAs of the ear height (EH), the kernel moisture content (KMC), the kernel ratio (KR), and the yield per plant (YPP) were estimated using these hybrids in three environments. Combining the high-density genetic map and the GCAs, a total of 14 QTLs were detected for the GCAs of the four traits. Especially, one pleiotropic QTL was identified on chromosome 1 between the SNP SYN16067 and the SNP PZE-101169244 which was simultaneously associated with the GCAs of the EH, the KR, and the YPP. These QTLs pave the way for further dissecting the genetic architecture underlying GCAs of the traits, and they may be used to enhance GCAs of inbred lines under the fixed heterotic pattern ReidxSipingtou in China through a marker-assisted selection approach.展开更多
Ancherythroculter nigrocauda is a fish endemic to the upper areas of the Changjiang(Yangtze)River in China.Quantitative trait locus(QTL)mapping is a powerful tool to identify potential genes affecting traits of econom...Ancherythroculter nigrocauda is a fish endemic to the upper areas of the Changjiang(Yangtze)River in China.Quantitative trait locus(QTL)mapping is a powerful tool to identify potential genes affecting traits of economic importance in domestic animals.In this study,a high-density genetic map was constructed with 5901 single nucleotide polymorphism(SNP)makers by sequencing 92 individual fish from a F1 family using the specific-locus amplified fragment sequencing approach.Initially,48 QTLs for total length,body length,body height,and body weight were identified according to the high density of the genetic map with 24 LGs,a total length of 3839.4 cM,and marker spacing of about 0.82 cM.These QTLs explained 27.1%-49.9%of phenotypic variance.The results of this study suggest that major QTLs are responsible for the growth of A.nigrocauda,and these are potentially useful in comparative genomics research,genome assembly,and marker-assisted breeding programs for this species.展开更多
F2:10 RIL population with 154 lines, crossed by Charleston as female parent and Dongnong 594 as male parent were used. 164 SSR primers were screened with the two parents and amplified on the 154 lines. A new soybean ...F2:10 RIL population with 154 lines, crossed by Charleston as female parent and Dongnong 594 as male parent were used. 164 SSR primers were screened with the two parents and amplified on the 154 lines. A new soybean molecular genetics map, named NEAUSRI-GMS, was constructed by Mapmaker. The total length of the soybean genetic map is 1 913.5 cM, and the average distance among markers is 11.89 cM. The length of linkage group varied from 0.4 to 309.5 cM, and the markers on the linkage group varied from 2 to 28. The distribution of SSR markers on every linkage group is not even. High density region of markers existed on linkage group A1, C2, and Dla. Compared with 5 soybean genetic maps constructed at home and abroad, NEAUSRI-GMS has high homologous with the public genetic map abroad.展开更多
Verticillium wilt is one of the most important diseases affecting cotton production in China.The fungus,Verticillium dahliae,has a wide host range and a high degree of genetic variability.No resistance resources have ...Verticillium wilt is one of the most important diseases affecting cotton production in China.The fungus,Verticillium dahliae,has a wide host range and a high degree of genetic variability.No resistance resources have been found in the available planting resources,thus presenting difficulties and challenges for our study.The long-term production practice shows that selection of disease-resistant varieties is the most economical and effective measure to control Verticillium wilt of cotton to reduce the yield loss and quality decline of cotton.In this paper,we summarized the genetic mapping population,the analysis method of genetic localization,the discovery,mining and cloning of disease-resistant quantitative trait loci/markers,and the analysis of their genetic functions,so as to provide information for the molecular breeding approach of disease-resistant cotton.展开更多
Dramatic changes in climatic conditions that supplement the biotic and abiotic stresses pose severe threat to the sustainable rice production and have made it a difficult task for rice molecular breeders to enhance pr...Dramatic changes in climatic conditions that supplement the biotic and abiotic stresses pose severe threat to the sustainable rice production and have made it a difficult task for rice molecular breeders to enhance production and productivity under these stress factors. The main focus of rice molecular breeders is to understand the fundamentals of molecular pathways involved in complex agronomic traits to increase the yield. The availability of complete rice genome sequence and recent improvements in rice genomics research has made it possible to detect and map accurately a large number of genes by using linkage to DNA markers. Linkage mapping is an effective approach to identify the genetic markers which are co-segregating with target traits within the family. The ideas of genetic diversity, quantitative trait locus(QTL) mapping, and marker-assisted selection(MAS) are evolving into more efficient concepts of linkage disequilibrium(LD) also called association mapping and genomic selection(GS), respectively. The use of cost-effective DNA markers derived from the fine mapped position of the genes for important agronomic traits will provide opportunities for breeders to develop high-yielding, stress-resistant, and better quality rice cultivars. Here we focus on the progress of molecular marker technologies, their application in genetic mapping and evolution of association mapping techniques in rice.展开更多
Adzuki bean(Vigna angularis(Willd.)Ohwi&Ohashi)is an annual cultivated leguminous crop commonly grown in Asia and consumed worldwide.However,there has been limited research regarding adzuki bean genetics,which has...Adzuki bean(Vigna angularis(Willd.)Ohwi&Ohashi)is an annual cultivated leguminous crop commonly grown in Asia and consumed worldwide.However,there has been limited research regarding adzuki bean genetics,which has prevented the efficient application of genes during breeding.In the present study,we constructed a high-density genetic map based on whole genome re-sequencing technology and validated its utility by mining QTLs related to seed size.Moreover,we analyzed the sequences flanking insertions/deletions(In Dels)to develop a set of PCR-based markers useful for characterizing adzuki bean genetics.A total of 2904 markers were mapped to 11 linkage groups(LGs).The total length of the map was 1365.0 cM,with an average distance between markers of 0.47 cM.Among the LGs,the number of markers ranged from 208(LG7)to 397(LG1)and the total distance ranged from 97.4 cM(LG9)to 155.6 cM(LG1).Twelve QTLs related to seed size were identified using the constructed map.The two major QTLs in LG2 and LG9 explained 22.1 and 18.8%of the total phenotypic variation,respectively.Ten minor QTLs in LG4,LG5 and LG6 explained 3.0–10.4%of the total phenotypic variation.A total of 9718 primer pairs were designed based on the sequences flanking In Dels.Among the 200 selected primer pairs,75 revealed polymorphisms in 24 adzuki bean germplasms.The genetic map constructed in this study will be useful for screening genes related to other traits.Furthermore,the QTL analysis of seed size and the novel markers described herein may be relevant for future molecular investigations of adzuki bean and will be useful for exploiting the mechanisms underlying legume seed development.展开更多
Background:Segregation distortion(SD)is a common phenomenon among stable or segregating populations,and the principle behind it still puzzles many researchers.The F2:3 progenies developed from the wild cotton species ...Background:Segregation distortion(SD)is a common phenomenon among stable or segregating populations,and the principle behind it still puzzles many researchers.The F2:3 progenies developed from the wild cotton species of the D genomes were used to investigate the possible plant transcription factors within the segregation distortion regions(SDRs).A consensus map was developed between two maps from the four D genomes,map A derived from F2:3 progenies of Gossypium klotzschianum and G.davidsonii while Map B from G.thurberi and G.trilobum F2:3 generations.In each map,188 individual plants were used.Results:The consensus linkage map had 1492 markers across the 13 linkage groups with a map size of 1467.445 cM and an average marker distance of 1.0370 cM.Chromosome D502 had the highest percentage of SD with 58.6%,followed by Chromosome D507 with 47.9%.Six thousand and thirty-eight genes were mined within the SDRs on chromosome D502 and D507 of the consensus map.Within chromosome D502 and D507,2308 and 3730 genes were mined,respectively,and were found to belong to 1117 gourp out of which 622 groups were common across the two chromosomes.Moreover,genes within the top 9 groups related to plant resistance genes(R genes),whereas 188 genes encoding protein kinase domain(PF00069)comprised the largest group.Further analysis of the dominant gene group revealed that 287 miRNAs were found to target various genes,such as the gra-miR398,gramiR5207,miR164a,miR164b,miR164c among others,which have been found to target top-ranked stress-responsive transcription factors such as NAC genes.Moreover,some of the stress-responsive cis-regulatory elements were also detected.Furthermore,RNA profiling of the genes from the dominant family showed that higher numbers of genes were highly upregulated under salt and osmotic stress conditions,and also they were highly expressed at different stages of fiber development.Conclusion:The results indicated the critical role of the SDRs in the evolution of the key regulatory genes in plants.展开更多
Cotton (Gossypium spp.) is the most important natural fiber in the world, and its seeds are also used as a food source. Breeding cotton for traits of interest, such as production and processing of fibers, will ensure ...Cotton (Gossypium spp.) is the most important natural fiber in the world, and its seeds are also used as a food source. Breeding cotton for traits of interest, such as production and processing of fibers, will ensure that this natural product is as competitive as renewable synthetic fibers derived from petroleum. Thus, the mapping of the cotton genome for traits of interest may be the basis for its subsequent use in breeding programs. This work consists of a literature review, with the aim of bringing together works from different research groups working with the mapping of the cotton genome with molecular markers.展开更多
Rose is one of the most important ornamental and economic plants in the world.Modern rose cultivars are primarily tetraploid,and during meiosis,they may exhibit double reduction or preferential chromosome pairing.Ther...Rose is one of the most important ornamental and economic plants in the world.Modern rose cultivars are primarily tetraploid,and during meiosis,they may exhibit double reduction or preferential chromosome pairing.Therefore,the construction of a high density genetic map of tetraploid rose is both challenging and instructive.In this study,a tetraploid rose population was used to conduct a genetic analysis using genome sequencing.A total of 17382 single nucleotide polymorphism(SNP)markers were selected from 2308042 detected SNPs.Combined with 440 previously developed simple sequence repeats(SSR)and amplified fragment length polymorphism(AFLP)markers,a marker dosage of 6885 high quality markers was successfully assigned by GATK software in the tetraploid model.These markers were used in the construction of a high density genetic map,containing the expected seven linkage groups with 6842 markers,a total map length of 1158.9 c M,and an average inter-marker distance of 0.18 c M.Quantitative trait locus(QTL)analysis was subsequently performed to characterize the genetic architecture of petal number and flower diameter.One major QTL(qpnum-3-1)was detected for petal number in three consecutive years,which explained 20.18–22.11%of the variation in petal number.Four QTLs were detected for flower diameter;the main locus,qfdia-2-2,was identified in two consecutive years.Our results will benefit the molecular marker-assisted breeding of modern rose cultivars.In addition,this study provides a guide for the genetic and QTL analysis of autotetraploid plants using sequencing-based genotyping methods.展开更多
Genetic mapping provides a powerful tool for the analysis of quantitative trait loci (QTLs) at the genomic level. Herein, we report a new genetic linkage map developed from an F1-derived doubled haploid (DH) popul...Genetic mapping provides a powerful tool for the analysis of quantitative trait loci (QTLs) at the genomic level. Herein, we report a new genetic linkage map developed from an F1-derived doubled haploid (DH) population of 168 lines, which was generated from the cross between two elite Chinese common wheat (Triticum aestivum L.) varieties, Huapei 3 and Yumai 57. The map contained 305 loci, represented by 283 simple sequence repeat (SSR) and 22 expressed sequence tag (EST)-SSR markers, which covered a total length of 2141.7 cM with an average distance of 7.02 cM between adjacent markers on the map. The chromosomal locations and map positions of 22 new SSR markers were determined, and were found to distribute on 14 linkage groups. Twenty SSR loci showed different chromosomal locations from those reported in other maps. Therefore, this map offers new information on the SSR markers of wheat. This genetic map provides new opportunities to detect and map QTLs controlling agronomically important traits. The unique features of this map are discussed.展开更多
Kenaf (Hibiscus cannabinus L.) is one of the most economically important crops for non-wood fiber production. The objective of this study was to establish a genetic linkage map of kenaf with higher density of molecu...Kenaf (Hibiscus cannabinus L.) is one of the most economically important crops for non-wood fiber production. The objective of this study was to establish a genetic linkage map of kenaf with higher density of molecular markers. A semi- wild variety Ga42 and a cultivar Alain kenaf were used as parents to construct an F2 population consisting of 155 plants. The genetic linkage map comprising 134 marker loci was constructed, including 65 sequence-related amplified polymorphism (SRAP), 56 inter-simple sequence repeat (ISSR), and 13 randomly amplified polymorphic DNA (RAPD) markers. This map spans 2 108.9 cM and contains 20 linkage groups with an average marker density of 15.7 cM between the adjacent markers.展开更多
A hybrid Ft population was obtained by crossing between mango cultivars ' Jinhuang' and ' Guifei'. Among the hybrid population, 98 F1 plants were selected as the mapping population. The molecular genetic map of ma...A hybrid Ft population was obtained by crossing between mango cultivars ' Jinhuang' and ' Guifei'. Among the hybrid population, 98 F1 plants were selected as the mapping population. The molecular genetic map of mango was constructed by linkage analysis by SRAP, AFLP and ISSR markers using Joinmap4. 0 software. The genetic linkage map consisted of 33 linkage groups, with a total genetic distance of 1 561.1 cM. Moreover, the genetic linkage map involved 245 polymorphic markers, including 149 SRAP markers, 90 AFLP markers and 6 ISSR markers, with an average genetic distance of 6.37 cM. This study laid a founda- tion for further investigation of the important agronomic traits of mango.展开更多
Genetic map is a linear arrangement of the relative positions of sites in the chromosome or genome based on the recombination frequency between genetic markers.It is the important basis for genetic analysis.Several ki...Genetic map is a linear arrangement of the relative positions of sites in the chromosome or genome based on the recombination frequency between genetic markers.It is the important basis for genetic analysis.Several kinds of software have been designed for genetic mapping,but all these tools require users to write or edit code,making it time-costing and difficult for researchers without programming skills to handle with.Here,MG2C,a new online tool was designed,based on PERL and SVG languages.Users can get a standard genetic map,only by providing the location of genes(or quantitative trait loci)and the length of the chromosome,without writing additional code.The operation interface of MG2C contains three sections:data input,data output and parameters.There are 33 attribute parameters in MG2C,which are further divided into 8 modules.Values of the parameters can be changed according to the users’requirements.The information submitted by users will be transformed into the genetic map in SVG file,which can be further modified by other image processing tools.MG2C is a user-friendly and time-saving online tool for drawing genetic maps,especially for those without programming skills.The tool has been running smoothly since 2015,and updated to version 2.1.It significantly lowers the technical barriers for the users,and provides great convenience for the researchers.展开更多
Erect milkvetch(Astragalus adsurgens)is a perennial legume forage crop with economic and ecological value in livestock grazing and soil-erosion control in arid and semiarid areas worldwide.Genomic information and mole...Erect milkvetch(Astragalus adsurgens)is a perennial legume forage crop with economic and ecological value in livestock grazing and soil-erosion control in arid and semiarid areas worldwide.Genomic information and molecular tools to support breeding and research in the species are limited.The objectives of this investigation were to map its genome using DNA markers and to identify quantitative trait loci(QTL)in the species.An F1 mapping population of 250 plants was developed from a cross between two parents with differing flowering-related traits.A high-density genetic linkage map containing 4821 markers on eight linkage groups(LGs)with a total genetic length of 1395 cM and a mean interval of 0.29 cM between adjacent markers was constructed with SLAF-seq technology.Comparative genomic analyses revealed the highest genome sequence similarity(8.71%)between erect milkvetch and Medicago truncatula,followed by Glycine max(7.65%),Cicer arietinum(7.53%),and Lupinus angustifolius(5.21%).A total of 64 significant QTL for flowering-related traits on six LGs were detected,accounting for 9.38 to 19.1%of the associated phenotype variation.Five and 48 key candidate genes for floret number and inflorescence length were identified based on the Glycyrrhiza uralensis genome.These candidate genes were involved in ubiquitination/degradation,pollen development,cell division,cytokinin biosynthetic process,and plant flowering.These findings shed light on the regulation of flowering traits in erect milkvetch and provide genomic resources for future molecular breeding of the crop.展开更多
基金financially supported by National Key R&D Program of China(Grant No.2019YFD1001401)Project of Construction of Grape Germplasm Resources Sharing Platform(Grant No.PT2029)+2 种基金Zhengzhou Major Scientific and Technological Innovation Projects(Grant No.2020CXZX0082)National Modern Agricultural Industry Technology System Construction Special Project(Grant No.CARS-29-yc-1)Special Project of Science,Technology Innovation Project of Chinese Academy of Agricultural Sciences(Grant No.CAAS-ASTIP-2019-ZFRI).
文摘Grape berry shape is an important agricultural trait.Clarifying its genetic basis is significant for cultivating grape varieties that meet market demands.However,the current study by forward genetics has not achieved in-depth results.Here,a high-density map was constructed to identify quantitative trait loci(QTLs)for berry shape.A total of 358709 polymorphic SNPs were obtained using whole-genome resequencing(WGS)based on 208 F2 individuals derived from round grape‘E42-6’and oblong grape‘Rizamat’.The 1635.65 cM high-density map was divided into 19 linkage groups with an average distance of 0.37 cM.Using this map,three significant QTLs for fruit shape index(ShI:ratio of berry length to berry width)identified over three years were mapped onto LG4 and LG5,including one stable QTL on Chr5 with the genomic region of 0.47–1.94 Mb.Combining with gene annotation and expression patterns based on RNA-seq data from two contrasting F2 individuals with round and oblong berry(their average ShI was 1.89 and 1.10,respectively)at four developmental stages,four candidate genes were selected from the above QTLs.They were mainly involved in DNA replication,cell wall modification,and phytohormone biosynthesis.Further analysis of RNA-seq data revealed that several important phytohormone synthesis and metabolic pathways were enriched based on differentially expressed genes(DEGs),which was consistent with the results of QTL mapping for genes related to plant hormone biosynthesis in the F2 population.Furthermore,a comparison of plant hormone content showed that there were significant differences in IAA and tZ content between the two contrasting F2 individuals at different developmental stages.Our findings provide molecular insights into the genetic variation in grape berry shape.Stable QTLs and their tightly linked markers offer the possibility of marker-assisted selection to accelerate berry shape breeding.
基金the Hainan Yazhou Bay Seed Laboratory(B21Y10209 and B22C10212)China Postdoctoral Science Foundation(2022M713433)+1 种基金National Natural Science Foundation of China(31861143003)Innovation Program of Chinese Academy of Agricultural Sciences.
文摘A large amount of genome-wide association study(GWAS)panels together with quantitative-trait locus(QTL)information associated with breeding-targeted traits have been described in wheat(Triticum aestivum L.).However,the application of mapping results from a GWAS panel to conventional wheat breeding remains a challenge.In this study,we first report a general genetic map which was constructed from 44 published linkage maps.It permits the estimation of genetic distances between any two genetic loci with physical map positions,thereby unifying the linkage relationships between QTL,genes,and genomic markers from multiple genetic populations.Second,we describe QTL mapping in a wheat GWAS panel of 688 accessions,identifying 77 QTL associated with 12 yield and grain-quality traits.Because these QTL have known physical map positions,they could be mapped onto the general map.Finally,we present a design approach to wheat breeding by using known QTL information and computer simulation.Potential crosses between parents in the GWAS panel may be evaluated by the relative frequency of the target genotype,trait correlations in simulated progeny populations,and genetic gain of selected progenies.It is possible to simultaneously improve yield and grain quality by suitable parental selection,progeny population size,and progeny selection scheme.Applying the design approach will allow identifying the most promising crosses and selection schemes in advance of the field experiment,increasing predictability and efficiency in wheat breeding.
基金supported by the National Key R&D Program of China(2019YFD1001300 and 2019YFD1001303)the Construction of Molecular Database of Faba Bean and Pea and Identification of Maize Germplasm Project,Ministry of Agriculture and Rural Affairs,China(19200030)+3 种基金the Yunnan Key R&D Program,China(202202AE090003)the earmarked fund for China Agriculture Research System(CARS-08)the Crop Germplasm Resources Protection(2130135)the Major Agricultural Science and Technology Program of Chinese Academy of Agricultural Sciences(CAAS-XTCX20190025)。
文摘Owing to the limitation of a large genome size(~13 Gb),the genetic and gene mapping studies on faba bean(Vicia faba L.)are lagging far behind those for other legumes.In this study,we selected three purified faba bean lines(Yundou 8137,H0003712,and H000572)as parents and constructed two F2 populations.These two F2 populations,namely 167 F2 plants in Pop1(Yundou 8137×H0003712)and 204 F2 plants in Pop2(H000572×Yundou 8137),were genotyped using a targeted next-generation sequencing(TNGS)genotyping platform,and two high-density single nucleotide polymorphisms(SNP)genetic linkage maps of faba bean were constructed.The map constructed from Pop1 contained 5103 SNPs with a length of 1333.31 cM and an average marker density of 0.26 cM.The map constructed from Pop2 contained 1904 SNPs with a greater length of 1610.61 cM.In these two F2 populations,QTL mapping identified 98 QTLs for 14 agronomic traits related to the flowers,pods,plant types and grains.The two maps were then merged into an integrated genetic linkage map containing 6895 SNPs,with a length of 3324.48 cM.These results not only lay the foundation for fine mapping and map-based cloning of related genes,but can also accelerate the molecular marker-assisted breeding of faba bean.
基金Supported by the Projects of the National Science and Technology Programs (2006AA10Z1F4)Heilongjiang Postdoctoral Science-Research Foundation (LHK-04014 & LRB06-126)+1 种基金Heilongjiang "11th Five-Year Plan" Science and Technology Research Projects (GA06B101-2-6)Heilongjiang Young Academic Supporting Project (1152G007)
文摘Soybean is a major crop in the world, and it is a main source of plant proteins and oil. A lot of soybean genetic maps and physical maps have been constructed, but there are no integrated map between soybean physical map and genetic map. In this study, soybean genome sequence data, released by JGI (US Department of Energy's Joint Genome Institute), had been downloaded. With the software Blast 2.2.16, a total of 161 super sequences were mapped on the soybean public genetic map to construct an integrated map. The length of these super sequences accounted for 73.08% of all the genome sequence. This integrated map could be used for gene cloning, gene mining, and comparative genome of legume.
基金funded by the Key-Area of Research and Development Program of Guangdong Province,China(2018B020202011)the National Natural Science Foundation of China(31701885)+2 种基金the China Agriculture Research System of MOF and MARA(CARS-32-05)the State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources,China(SKLCUSA-b201716)the YangFan Innovative&Entrepreneurial Research Team Project,China(2014YT02H013)。
文摘Litchi chinensis Sonn is widely cultivated in subtropical regions and has an important economic value.A high-density genetic map is a valuable tool for mapping quantitative trait loci(QTL)and marker-assisted breeding programs.In this study,a single nucleotide polymorphism(SNP)-based high-density linkage map was constructed by a genotyping-by-sequencing(GBS)protocol using an F1 population of 178 progenies between two commercial litchi cultivars,‘Ziniangxi’(dwarf)and‘Feizixiao’(vigorous).The genetic map consisted of 3027 SNP markers with a total length of 1711.97 cM in 15 linkage groups(LGs)and an average marker distance of 0.57 cM.Based on this high-density linkage map and three years of phenotyping,a total of 37 QTLs were detected for eight dwarf-related traits,including length of new branch(LNB),diameter of new branch(DNB),length of common petiole(LCP),diameter of common petiole(DCP),length of internode(LI),length of single leaf(LSL),width of single leaf(WSL),and plant height(PH).These QTLs could explain 8.0 to 14.7%(mean=9.7%)of the phenotypic variation.Among them,several QTL clusters were observed,particularly on LG04 and LG11,which might show enrichment for genes regulating the dwarf-related traits in litchi.There were 126 candidate genes identified within the QTL regions,55 of which are differentially expressed genes by RNA-seq analysis between‘Ziniangxi’and‘Feizixiao’.These DEGs were found to participate in the regulation of cell development,material transportation,signal transduction,and plant morphogenesis,so they might play important roles in regulating plant dwarf-related traits.The high-density genetic map and QTLs identification related to dwarf traits can provide a valuable genetic resource and a basis for marker-assisted selection and genomic studies of litchi.
基金supported by Key Realm R&D Program of Guangdong Province(Grant No.2020B020220003)the National Natural Science Foundation of China(Grant No.31601748)the Agricultural competitive industry discipline team building project of Guangdong Academy of Agricultural Sciences(Grant No.202103TD).
文摘Long-day length and high temperature inhibit sex expression in pumpkin(Cucurbita moschata Duch.),and therefore directly impact the production potential.In this study,female flowering patterns in photoperiod-insensitive(PPIS)and photoperiod-sensitive(PPS)germplasms differed significantly in a moderately long day and high temperature environment.However,both germplasms exhibited a similar response in short day with either low temperature or high temperature environment.Photoperiod sensitivity led to this difference in sex expression between the germplasms.For the traits of 1st female flowering node(FFFN)and number of female flowers(NFF),high-density linkage map construction and quantitative trait locus(QTL)mapping were performed using SLAF-seq technology and 162 F_(2) individuals generated from PPIS and PPS.In total,4655 SLAFs were selected and mapped on 20 linkage groups(LGs).The total map length was 2502.01 cM with an average interval distance of 0.75 cM.Major QTLs for both FFFN and NFF were detected on LG6 with intervals of 7.89 and 17.67 cM and PVE values of 30.5%and 22.9%,respectively.Further analyses of the major locus for FFFN revealed 73 protein-coding genes.Among them,4 were related to sex expression,photoperiod flowering,and hormone response.An InDel(insertion and deletion)marker partially correlated with FFFN of the F_(2) population was also developed.Our study identified the QTL for the sex expression response to environmental factors using the high-density linkage map.The identified candidate genes and markers will provide useful information about the molecular interaction between the environment and sex expression and for marker-assisted selection of pumpkin environment-insensitive resources.
基金financially supported by the National Key Research and Development Plan of China(2016YFD0101200)
文摘General combining abilities (GCAs) are very important in utilization of heterosis in maize breeding. However, its genetic basis is unclear. In the present study, a set of 118 doubled haploid (DH) lines were induced from F1 generations produced from the cross between the inbred line Zheng 58 and the inbred line W499 belonging to the Reid subgroup. Using the MaizeSNP50 BeadChip, a high-density genetic map was constructed based on the DH population which included 1 147 bin markers with an average interval length of 2.00 cM. Meanwhile, the DH population was crossed with three testers including W16-5, HD568, and W556, which belong to the Sipingtou subgroup. The GCAs of the ear height (EH), the kernel moisture content (KMC), the kernel ratio (KR), and the yield per plant (YPP) were estimated using these hybrids in three environments. Combining the high-density genetic map and the GCAs, a total of 14 QTLs were detected for the GCAs of the four traits. Especially, one pleiotropic QTL was identified on chromosome 1 between the SNP SYN16067 and the SNP PZE-101169244 which was simultaneously associated with the GCAs of the EH, the KR, and the YPP. These QTLs pave the way for further dissecting the genetic architecture underlying GCAs of the traits, and they may be used to enhance GCAs of inbred lines under the fixed heterotic pattern ReidxSipingtou in China through a marker-assisted selection approach.
基金Supported by the Technical Innovation Project of Hubei Province(No.2018ABA105)the Enterprise Technology Innovation Project of Wuhan(No.39 of 2019 WuKe)。
文摘Ancherythroculter nigrocauda is a fish endemic to the upper areas of the Changjiang(Yangtze)River in China.Quantitative trait locus(QTL)mapping is a powerful tool to identify potential genes affecting traits of economic importance in domestic animals.In this study,a high-density genetic map was constructed with 5901 single nucleotide polymorphism(SNP)makers by sequencing 92 individual fish from a F1 family using the specific-locus amplified fragment sequencing approach.Initially,48 QTLs for total length,body length,body height,and body weight were identified according to the high density of the genetic map with 24 LGs,a total length of 3839.4 cM,and marker spacing of about 0.82 cM.These QTLs explained 27.1%-49.9%of phenotypic variance.The results of this study suggest that major QTLs are responsible for the growth of A.nigrocauda,and these are potentially useful in comparative genomics research,genome assembly,and marker-assisted breeding programs for this species.
基金This work was supported by the National 863 Program of China(20012AA211041)National Key Technolo-gies R&D Program of China(2004BA907A26)Young Science Foundation of Harbin,China(2002AFQXJ043).
文摘F2:10 RIL population with 154 lines, crossed by Charleston as female parent and Dongnong 594 as male parent were used. 164 SSR primers were screened with the two parents and amplified on the 154 lines. A new soybean molecular genetics map, named NEAUSRI-GMS, was constructed by Mapmaker. The total length of the soybean genetic map is 1 913.5 cM, and the average distance among markers is 11.89 cM. The length of linkage group varied from 0.4 to 309.5 cM, and the markers on the linkage group varied from 2 to 28. The distribution of SSR markers on every linkage group is not even. High density region of markers existed on linkage group A1, C2, and Dla. Compared with 5 soybean genetic maps constructed at home and abroad, NEAUSRI-GMS has high homologous with the public genetic map abroad.
基金supported by the National Natural Science Foundation of China(31760402)Young and Middle-aged Science and Technology Leading Talents of Xinjiang Production and Construction Corps(2019CB027)+1 种基金Science and Technology Innovation Talent Plan of Xinjiang Production and Construction Corps(2021CB028)National Natural Funds-Xinjiang Joint Fund(U1703231).
文摘Verticillium wilt is one of the most important diseases affecting cotton production in China.The fungus,Verticillium dahliae,has a wide host range and a high degree of genetic variability.No resistance resources have been found in the available planting resources,thus presenting difficulties and challenges for our study.The long-term production practice shows that selection of disease-resistant varieties is the most economical and effective measure to control Verticillium wilt of cotton to reduce the yield loss and quality decline of cotton.In this paper,we summarized the genetic mapping population,the analysis method of genetic localization,the discovery,mining and cloning of disease-resistant quantitative trait loci/markers,and the analysis of their genetic functions,so as to provide information for the molecular breeding approach of disease-resistant cotton.
文摘Dramatic changes in climatic conditions that supplement the biotic and abiotic stresses pose severe threat to the sustainable rice production and have made it a difficult task for rice molecular breeders to enhance production and productivity under these stress factors. The main focus of rice molecular breeders is to understand the fundamentals of molecular pathways involved in complex agronomic traits to increase the yield. The availability of complete rice genome sequence and recent improvements in rice genomics research has made it possible to detect and map accurately a large number of genes by using linkage to DNA markers. Linkage mapping is an effective approach to identify the genetic markers which are co-segregating with target traits within the family. The ideas of genetic diversity, quantitative trait locus(QTL) mapping, and marker-assisted selection(MAS) are evolving into more efficient concepts of linkage disequilibrium(LD) also called association mapping and genomic selection(GS), respectively. The use of cost-effective DNA markers derived from the fine mapped position of the genes for important agronomic traits will provide opportunities for breeders to develop high-yielding, stress-resistant, and better quality rice cultivars. Here we focus on the progress of molecular marker technologies, their application in genetic mapping and evolution of association mapping techniques in rice.
基金supported by the National Key Research&Development Program of China(2019YFD1001300 and 2019YFD1001303)the earmarked fund for China Agriculture Research System(CARS-08)the Agricultural Science Technology Innovation Program(ASTIP)of Chinese Academy of Agricultural Sciences。
文摘Adzuki bean(Vigna angularis(Willd.)Ohwi&Ohashi)is an annual cultivated leguminous crop commonly grown in Asia and consumed worldwide.However,there has been limited research regarding adzuki bean genetics,which has prevented the efficient application of genes during breeding.In the present study,we constructed a high-density genetic map based on whole genome re-sequencing technology and validated its utility by mining QTLs related to seed size.Moreover,we analyzed the sequences flanking insertions/deletions(In Dels)to develop a set of PCR-based markers useful for characterizing adzuki bean genetics.A total of 2904 markers were mapped to 11 linkage groups(LGs).The total length of the map was 1365.0 cM,with an average distance between markers of 0.47 cM.Among the LGs,the number of markers ranged from 208(LG7)to 397(LG1)and the total distance ranged from 97.4 cM(LG9)to 155.6 cM(LG1).Twelve QTLs related to seed size were identified using the constructed map.The two major QTLs in LG2 and LG9 explained 22.1 and 18.8%of the total phenotypic variation,respectively.Ten minor QTLs in LG4,LG5 and LG6 explained 3.0–10.4%of the total phenotypic variation.A total of 9718 primer pairs were designed based on the sequences flanking In Dels.Among the 200 selected primer pairs,75 revealed polymorphisms in 24 adzuki bean germplasms.The genetic map constructed in this study will be useful for screening genes related to other traits.Furthermore,the QTL analysis of seed size and the novel markers described herein may be relevant for future molecular investigations of adzuki bean and will be useful for exploiting the mechanisms underlying legume seed development.
基金This research program was financially sponsored by the National Key Research and Development Plan(2016YFD0100306)the National Natural Science Foundation of China(31671745,31530053).
文摘Background:Segregation distortion(SD)is a common phenomenon among stable or segregating populations,and the principle behind it still puzzles many researchers.The F2:3 progenies developed from the wild cotton species of the D genomes were used to investigate the possible plant transcription factors within the segregation distortion regions(SDRs).A consensus map was developed between two maps from the four D genomes,map A derived from F2:3 progenies of Gossypium klotzschianum and G.davidsonii while Map B from G.thurberi and G.trilobum F2:3 generations.In each map,188 individual plants were used.Results:The consensus linkage map had 1492 markers across the 13 linkage groups with a map size of 1467.445 cM and an average marker distance of 1.0370 cM.Chromosome D502 had the highest percentage of SD with 58.6%,followed by Chromosome D507 with 47.9%.Six thousand and thirty-eight genes were mined within the SDRs on chromosome D502 and D507 of the consensus map.Within chromosome D502 and D507,2308 and 3730 genes were mined,respectively,and were found to belong to 1117 gourp out of which 622 groups were common across the two chromosomes.Moreover,genes within the top 9 groups related to plant resistance genes(R genes),whereas 188 genes encoding protein kinase domain(PF00069)comprised the largest group.Further analysis of the dominant gene group revealed that 287 miRNAs were found to target various genes,such as the gra-miR398,gramiR5207,miR164a,miR164b,miR164c among others,which have been found to target top-ranked stress-responsive transcription factors such as NAC genes.Moreover,some of the stress-responsive cis-regulatory elements were also detected.Furthermore,RNA profiling of the genes from the dominant family showed that higher numbers of genes were highly upregulated under salt and osmotic stress conditions,and also they were highly expressed at different stages of fiber development.Conclusion:The results indicated the critical role of the SDRs in the evolution of the key regulatory genes in plants.
文摘Cotton (Gossypium spp.) is the most important natural fiber in the world, and its seeds are also used as a food source. Breeding cotton for traits of interest, such as production and processing of fibers, will ensure that this natural product is as competitive as renewable synthetic fibers derived from petroleum. Thus, the mapping of the cotton genome for traits of interest may be the basis for its subsequent use in breeding programs. This work consists of a literature review, with the aim of bringing together works from different research groups working with the mapping of the cotton genome with molecular markers.
基金the National Natural Science Foundation of China(31600565)the Fundamental Research Funds for the Central Public Welfare Research Institutes,China(ZZ13-YQ-053)+1 种基金the Special Fund for Beijing Common Construction Project,ChinaDr.Peter M.Bourke from Plant Breeding,Wageningen University&Research,The Netherlands,was partly funded through the TKI polyploids project(BO-26.03-009-004 and BO-50-002-022)。
文摘Rose is one of the most important ornamental and economic plants in the world.Modern rose cultivars are primarily tetraploid,and during meiosis,they may exhibit double reduction or preferential chromosome pairing.Therefore,the construction of a high density genetic map of tetraploid rose is both challenging and instructive.In this study,a tetraploid rose population was used to conduct a genetic analysis using genome sequencing.A total of 17382 single nucleotide polymorphism(SNP)markers were selected from 2308042 detected SNPs.Combined with 440 previously developed simple sequence repeats(SSR)and amplified fragment length polymorphism(AFLP)markers,a marker dosage of 6885 high quality markers was successfully assigned by GATK software in the tetraploid model.These markers were used in the construction of a high density genetic map,containing the expected seven linkage groups with 6842 markers,a total map length of 1158.9 c M,and an average inter-marker distance of 0.18 c M.Quantitative trait locus(QTL)analysis was subsequently performed to characterize the genetic architecture of petal number and flower diameter.One major QTL(qpnum-3-1)was detected for petal number in three consecutive years,which explained 20.18–22.11%of the variation in petal number.Four QTLs were detected for flower diameter;the main locus,qfdia-2-2,was identified in two consecutive years.Our results will benefit the molecular marker-assisted breeding of modern rose cultivars.In addition,this study provides a guide for the genetic and QTL analysis of autotetraploid plants using sequencing-based genotyping methods.
基金the National Natural Science Foundation of China (30671270)the Hi-Tech Research and Development (863) Program of China(2006AA10Z1E9 and 2006AA100101)
文摘Genetic mapping provides a powerful tool for the analysis of quantitative trait loci (QTLs) at the genomic level. Herein, we report a new genetic linkage map developed from an F1-derived doubled haploid (DH) population of 168 lines, which was generated from the cross between two elite Chinese common wheat (Triticum aestivum L.) varieties, Huapei 3 and Yumai 57. The map contained 305 loci, represented by 283 simple sequence repeat (SSR) and 22 expressed sequence tag (EST)-SSR markers, which covered a total length of 2141.7 cM with an average distance of 7.02 cM between adjacent markers on the map. The chromosomal locations and map positions of 22 new SSR markers were determined, and were found to distribute on 14 linkage groups. Twenty SSR loci showed different chromosomal locations from those reported in other maps. Therefore, this map offers new information on the SSR markers of wheat. This genetic map provides new opportunities to detect and map QTLs controlling agronomically important traits. The unique features of this map are discussed.
基金supported by the National Natural Science Fundation of China (30571188 and 31000734)the National Agri-Industry Technology Research System for Crops of Bast and Leaf Fiber, China (nycytx-19-E05)the Construction of Germplasm Resources Platform for Bast Fiber Crops in Fujian, China (2010N2002)
文摘Kenaf (Hibiscus cannabinus L.) is one of the most economically important crops for non-wood fiber production. The objective of this study was to establish a genetic linkage map of kenaf with higher density of molecular markers. A semi- wild variety Ga42 and a cultivar Alain kenaf were used as parents to construct an F2 population consisting of 155 plants. The genetic linkage map comprising 134 marker loci was constructed, including 65 sequence-related amplified polymorphism (SRAP), 56 inter-simple sequence repeat (ISSR), and 13 randomly amplified polymorphic DNA (RAPD) markers. This map spans 2 108.9 cM and contains 20 linkage groups with an average marker density of 15.7 cM between the adjacent markers.
基金Supported by National Key Technology R&D Program"Breeding of New Varieties of Mango and Litchi"(2013BAD02B02-5)
文摘A hybrid Ft population was obtained by crossing between mango cultivars ' Jinhuang' and ' Guifei'. Among the hybrid population, 98 F1 plants were selected as the mapping population. The molecular genetic map of mango was constructed by linkage analysis by SRAP, AFLP and ISSR markers using Joinmap4. 0 software. The genetic linkage map consisted of 33 linkage groups, with a total genetic distance of 1 561.1 cM. Moreover, the genetic linkage map involved 245 polymorphic markers, including 149 SRAP markers, 90 AFLP markers and 6 ISSR markers, with an average genetic distance of 6.37 cM. This study laid a founda- tion for further investigation of the important agronomic traits of mango.
基金This work was funded by Science Foundation for Young Scholars of Tobacco Research Institute of Chinese Academy of Agricultural Sciences(2017B06)the Agricultural Science and Technology Innovation Program(ASTIPTRIC02)China Tobacco Genome Project(Grant No.202013-KN274).
文摘Genetic map is a linear arrangement of the relative positions of sites in the chromosome or genome based on the recombination frequency between genetic markers.It is the important basis for genetic analysis.Several kinds of software have been designed for genetic mapping,but all these tools require users to write or edit code,making it time-costing and difficult for researchers without programming skills to handle with.Here,MG2C,a new online tool was designed,based on PERL and SVG languages.Users can get a standard genetic map,only by providing the location of genes(or quantitative trait loci)and the length of the chromosome,without writing additional code.The operation interface of MG2C contains three sections:data input,data output and parameters.There are 33 attribute parameters in MG2C,which are further divided into 8 modules.Values of the parameters can be changed according to the users’requirements.The information submitted by users will be transformed into the genetic map in SVG file,which can be further modified by other image processing tools.MG2C is a user-friendly and time-saving online tool for drawing genetic maps,especially for those without programming skills.The tool has been running smoothly since 2015,and updated to version 2.1.It significantly lowers the technical barriers for the users,and provides great convenience for the researchers.
基金supported by the Chinese Universities Scientific Fund(2021RC001)the China Agriculture Research System(CARS34)the National Program for Forage Germplasm Conservation(2130135).
文摘Erect milkvetch(Astragalus adsurgens)is a perennial legume forage crop with economic and ecological value in livestock grazing and soil-erosion control in arid and semiarid areas worldwide.Genomic information and molecular tools to support breeding and research in the species are limited.The objectives of this investigation were to map its genome using DNA markers and to identify quantitative trait loci(QTL)in the species.An F1 mapping population of 250 plants was developed from a cross between two parents with differing flowering-related traits.A high-density genetic linkage map containing 4821 markers on eight linkage groups(LGs)with a total genetic length of 1395 cM and a mean interval of 0.29 cM between adjacent markers was constructed with SLAF-seq technology.Comparative genomic analyses revealed the highest genome sequence similarity(8.71%)between erect milkvetch and Medicago truncatula,followed by Glycine max(7.65%),Cicer arietinum(7.53%),and Lupinus angustifolius(5.21%).A total of 64 significant QTL for flowering-related traits on six LGs were detected,accounting for 9.38 to 19.1%of the associated phenotype variation.Five and 48 key candidate genes for floret number and inflorescence length were identified based on the Glycyrrhiza uralensis genome.These candidate genes were involved in ubiquitination/degradation,pollen development,cell division,cytokinin biosynthetic process,and plant flowering.These findings shed light on the regulation of flowering traits in erect milkvetch and provide genomic resources for future molecular breeding of the crop.