Three residual heterozygous lines (RHLs) carrying heterozygous segments in the intervals RM587–RM225, RM204–RM6119 and RM6119–RM402 on the short arm of rice chromosome 6, respectively, were selected from a rice pop...Three residual heterozygous lines (RHLs) carrying heterozygous segments in the intervals RM587–RM225, RM204–RM6119 and RM6119–RM402 on the short arm of rice chromosome 6, respectively, were selected from a rice population derived from an RHL for the interval RM587–RM402. Ten maternal homozygotes, 10 paternal homozygotes and 20 heterozygotes were selected from each of the F2 populations derived from the three RHLs. The three sets of near isogenic lines (NILs) were grown to detect the grain yield per plant, number of panicles per plant, number of filled grains per panicle and 1000-grain weight. With analysis on the phenotypic differences among the three genotype groups in each NIL set and those among overlapping chromosome segment substitution lines, three QTLs for number of filled grains per panicle and two QTLs for grain yield per plant were resolved. They were located in the intervals ranging from 0.66 Mb to 2.49 Mb. The additive effect was higher than the dominance effect at each locus. The allele for increasing the trait value was derived from the paternal parent at qNFGP6-1, and from the maternal alleles at other QTLs. Based on the present study, an approach for constructing new genetic resource to facilitate fine mapping of QTLs in rice was proposed.展开更多
The results of QTL mapping based on a primary mapping population should be further verified and refined for its real utilization in marker-assisted selection or map-based cloning.The primary mapping population contain...The results of QTL mapping based on a primary mapping population should be further verified and refined for its real utilization in marker-assisted selection or map-based cloning.The primary mapping population contains 114 BC1F1 plants of the backcross between Essex (maturity group V,MG V) as the donor parent and ZDD2315 (MG II) as the recurrent parent.In this study,a genetic linkage map with 250 SSR markers spanning a total length of 2963.5 cM on 25 linkage groups (LG) was constructed using software MAPMAKER3.0.Six kinds of genetic statistical models of 4 softwares,i.e.WinQTL Cartographer Version 2.5,IciMapping Version 2.0,MapQTL Version 5.0 and QTLnetwork Version 2.0,were used to map QTLs conferring days to flowering of the BC1F3 lines.Nine QTLs were mapped on 6 different linkage groups (LG).Of those,6 QTLs were detected by at least two different genetic statistical models,while the other three were detected by only one procedure.Among the three QTLs,Flwdt7 was mapped between Sat_213 and Satt643 on LG C2 with only 11.0% contribution rate.For confirmation of Flwdt7,5 RHL populations were developed through selfing eight BC1F5 plants heterozygous at seven markers around the locus.The RHL populations with the same segregating loci were bulked and used to construct a secondary linkage map of the specific segment using software JoinMap 3.0.The genetic distances among the markers on the specific segment became shorter than those of the whole genome map.On the secondary map,Flwdt7 was mapped between Satt277 and Satt489,next to its primary interval Sat_213-Satt643,with distance 1.40 cM to Satt277 and 0.45 cM to Satt489,confidence interval narrowed to 2.7 cM,and contribution rate increased to 36.8%.The results were confirmed with significance analysis among marker genotypes on individual loci and comparison analysis of target marker intervals among near isogenic lines (plants).Thus the strategy by using residual heterozygous lines for QTL fine-mapping on target segments based on primary whole genome scanning with multiple mapping models was demonstrated to be effective.展开更多
Soybean mosaic virus (SMV) disease is one of the most destructive viral diseases in soybean (Glycine max (L.) Merr.). SMV strain SC3 is the major prevalent strain in huang-huai and Yangtze valleys, China. The so...Soybean mosaic virus (SMV) disease is one of the most destructive viral diseases in soybean (Glycine max (L.) Merr.). SMV strain SC3 is the major prevalent strain in huang-huai and Yangtze valleys, China. The soybean cultivar Qihuang 1 is of a rich resistance spectrum and has a wide range of application in breeding programs in China. In this study, F1, F2 and F2:3 from Qihuang 1×nannong 1138-2 were used to study inheritance and linkage mapping of the SC3 resistance gene in Qihuang 1. The secondary F2 population and near isogenic lines (nILs) derived from residual heterozygous lines (RhLs) of Qihuang 1×nannong 1138-2 were separatively used in the ifne mapping and candidate gene analysis of the resistance gene. Results indicated that a single dominant gene (designated RSC3Q) controls resistance, which was located on chromosome 13. Two genomic-simple sequence repeat (SSR) markers BARCSOYSSR_13_1114 and BARCSOYSSR_13_1136 were found lfanking the two sides of the RSC3Q. The interval between the two markers was 651 kb. Quantitative real-time PCR analysis of the candidate genes showed that ifve genes (Glyma13g25730, 25750, 25950, 25970 and 26000) were likely involved in soybean SMV resistance. These results would have utility in cloning of RSC3Q resistance candidate gene and marker-assisted selection (MaS) in resistance breeding to SMV.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
This study was undertaken to dissect quantitative trait loci (QTLs) controlling yield traits on the short arm of rice chromosome 6. A residual heterozygous line that carries a heterozygous segment extending from RM5...This study was undertaken to dissect quantitative trait loci (QTLs) controlling yield traits on the short arm of rice chromosome 6. A residual heterozygous line that carries a heterozygous segment extending from RM587 to RM19784 on the short arm of rice chromosome 6 was selected from an F7 population of the indica rice cross Zhenshan 97B/Milyang 46. An F2:3 population consisting of 221 lines was derived and grown in two trial sites. Six yield traits including number of panicles per plant, number of filled grains per panicle, total number of spikelets per panicle, spikelet fertility, 1 000-grain weight, and grain yield per plant were measured. An SSR marker linkage map was constructed and employed to determine QTLs for yield traits with Windows QTL Cartographer 2.5. QTLs were detected in the target interval for all the traits analyzed except NP, with phenotypic variance explained by a single QTL ranging between 6.3% and 35.2%. Most of the QTLs for yield components acted as additive QTLs, while the three QTLs for grain yield had dominance degrees of 1.65, 0.84, and -0.42, respectively. It was indicated that three or more QTLs for yield traits were located in the target region. The genetic action mode, the direction of the QTL effect, and the magnitude of the QTL effect varied among different QTLs for a given trait, and among QTLs for different traits that were located in the same interval.展开更多
The QTL qHUS6 for hull silicon content in rice was previously located on the short arm of rice chromosome 6. By using an F2:3 population segregating in the RM587-RM19784 region harboring qHUS6 in an isogenic backgrou...The QTL qHUS6 for hull silicon content in rice was previously located on the short arm of rice chromosome 6. By using an F2:3 population segregating in the RM587-RM19784 region harboring qHUS6 in an isogenic background, two QTLs for hull silicon content were detected, of which qHUS6-1 was located in the distal region and qHUS6.2 in the region proximal to the centromere. Three rice plants carrying small heterozygous segments in the target region were selected, of which two covered the qHUS6-1 region and the other covered the qHUS6-2 region. Three F2:3 populations were derived from the selfed seeds of the three plants, respectively. QTL mapping was performed using the two populations segregating in the qHUS6-1 region, and qHUS6-1 was delimited to a 147.0-kb region flanked by the markers RM510 and RM19417. Five groups of F3 lines with different genotypic compositions in the qHUS6-2 region were selected from the other F2-3 population. Two QTLs were separated with two-way ANOVA, of which qHUS6-2a was located in the interval defined by RM19706-RM19795 and qHUS6-2b in the interval RM314-RM19665.展开更多
A rice residual heterozygous line (RHL) carrying a heterozygous segment extending from RM111 to RM19784 on the short arm of rice chromosome 6 was selected from a RHL-derived population used previously. The resultant...A rice residual heterozygous line (RHL) carrying a heterozygous segment extending from RM111 to RM19784 on the short arm of rice chromosome 6 was selected from a RHL-derived population used previously. The resultant F2:3 population was used to detect quantitative trait loci (QTLs) for three yield traits, the number of spikelets per panicle (NSP), the number of grains per panicle (NGP) and grain yield per plant (GY). Two QTLs for NSP, one QTL for NGP and one QTL for GY were detected, all of which were partially dominant and had the enhancing alleles from the maternal line Zhenshan 97B. Analysis based on the genotypic groups of the markers closely linked to the two QTLs for NSP indicated that they did not interact with each other. Two F2 populations and two near isogenic line (NIL) sets segregating in two sub-regions of interval RM111-RM19784 were developed. The two QTLs for NSP were validated, of which one had major effect and was co-segregated with heading date gene Hdl, and the other had smaller effect and was located in an upper region linked to Hdl. The two regions also showed significant effects on the number of filled grain and grain yield, although the effect on the number of filled grain was less consistent.展开更多
基金supported by the National High Technology Research and Development Program of China (Grant No. 2006AA10Z1E8)the Super Rice Program of Ministry of Agriculture, China (Grant No. 200606)the Natural Science Foundation of Zhejiang Province, China (Grant No. Y304446).
文摘Three residual heterozygous lines (RHLs) carrying heterozygous segments in the intervals RM587–RM225, RM204–RM6119 and RM6119–RM402 on the short arm of rice chromosome 6, respectively, were selected from a rice population derived from an RHL for the interval RM587–RM402. Ten maternal homozygotes, 10 paternal homozygotes and 20 heterozygotes were selected from each of the F2 populations derived from the three RHLs. The three sets of near isogenic lines (NILs) were grown to detect the grain yield per plant, number of panicles per plant, number of filled grains per panicle and 1000-grain weight. With analysis on the phenotypic differences among the three genotype groups in each NIL set and those among overlapping chromosome segment substitution lines, three QTLs for number of filled grains per panicle and two QTLs for grain yield per plant were resolved. They were located in the intervals ranging from 0.66 Mb to 2.49 Mb. The additive effect was higher than the dominance effect at each locus. The allele for increasing the trait value was derived from the paternal parent at qNFGP6-1, and from the maternal alleles at other QTLs. Based on the present study, an approach for constructing new genetic resource to facilitate fine mapping of QTLs in rice was proposed.
基金supported by the National Key Basic Research Program of China (Grant Nos.2006CB1017,2009CB1184)National High-Tech Research and Developmetn Program of China (Grant No.2006AA100104)+2 种基金National Natural Science Foundation of China (Grant No.30671266)National Key Technology Research and Development Program of China (Grant No.2006BAD13B05-7)Programme of Introducing Talents of Discipline to Universities (Grant No.B08025)
文摘The results of QTL mapping based on a primary mapping population should be further verified and refined for its real utilization in marker-assisted selection or map-based cloning.The primary mapping population contains 114 BC1F1 plants of the backcross between Essex (maturity group V,MG V) as the donor parent and ZDD2315 (MG II) as the recurrent parent.In this study,a genetic linkage map with 250 SSR markers spanning a total length of 2963.5 cM on 25 linkage groups (LG) was constructed using software MAPMAKER3.0.Six kinds of genetic statistical models of 4 softwares,i.e.WinQTL Cartographer Version 2.5,IciMapping Version 2.0,MapQTL Version 5.0 and QTLnetwork Version 2.0,were used to map QTLs conferring days to flowering of the BC1F3 lines.Nine QTLs were mapped on 6 different linkage groups (LG).Of those,6 QTLs were detected by at least two different genetic statistical models,while the other three were detected by only one procedure.Among the three QTLs,Flwdt7 was mapped between Sat_213 and Satt643 on LG C2 with only 11.0% contribution rate.For confirmation of Flwdt7,5 RHL populations were developed through selfing eight BC1F5 plants heterozygous at seven markers around the locus.The RHL populations with the same segregating loci were bulked and used to construct a secondary linkage map of the specific segment using software JoinMap 3.0.The genetic distances among the markers on the specific segment became shorter than those of the whole genome map.On the secondary map,Flwdt7 was mapped between Satt277 and Satt489,next to its primary interval Sat_213-Satt643,with distance 1.40 cM to Satt277 and 0.45 cM to Satt489,confidence interval narrowed to 2.7 cM,and contribution rate increased to 36.8%.The results were confirmed with significance analysis among marker genotypes on individual loci and comparison analysis of target marker intervals among near isogenic lines (plants).Thus the strategy by using residual heterozygous lines for QTL fine-mapping on target segments based on primary whole genome scanning with multiple mapping models was demonstrated to be effective.
基金supported by the National Natural Science Foundation of China (31171574, 31371646)the National Soybean Industrial Technology System of China (CARS-004)the Fund for Transgenic Breeding of Soybean Resistant to Soybean Mosaic Virus, China (2008ZX08004-004)
文摘Soybean mosaic virus (SMV) disease is one of the most destructive viral diseases in soybean (Glycine max (L.) Merr.). SMV strain SC3 is the major prevalent strain in huang-huai and Yangtze valleys, China. The soybean cultivar Qihuang 1 is of a rich resistance spectrum and has a wide range of application in breeding programs in China. In this study, F1, F2 and F2:3 from Qihuang 1×nannong 1138-2 were used to study inheritance and linkage mapping of the SC3 resistance gene in Qihuang 1. The secondary F2 population and near isogenic lines (nILs) derived from residual heterozygous lines (RhLs) of Qihuang 1×nannong 1138-2 were separatively used in the ifne mapping and candidate gene analysis of the resistance gene. Results indicated that a single dominant gene (designated RSC3Q) controls resistance, which was located on chromosome 13. Two genomic-simple sequence repeat (SSR) markers BARCSOYSSR_13_1114 and BARCSOYSSR_13_1136 were found lfanking the two sides of the RSC3Q. The interval between the two markers was 651 kb. Quantitative real-time PCR analysis of the candidate genes showed that ifve genes (Glyma13g25730, 25750, 25950, 25970 and 26000) were likely involved in soybean SMV resistance. These results would have utility in cloning of RSC3Q resistance candidate gene and marker-assisted selection (MaS) in resistance breeding to SMV.
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 Zhejiang Natural Science Foundation(Y304446)the National 863 Program of China(2006AA10Z1E8)the Chinese Super Rice Breeding Program(200606).
文摘This study was undertaken to dissect quantitative trait loci (QTLs) controlling yield traits on the short arm of rice chromosome 6. A residual heterozygous line that carries a heterozygous segment extending from RM587 to RM19784 on the short arm of rice chromosome 6 was selected from an F7 population of the indica rice cross Zhenshan 97B/Milyang 46. An F2:3 population consisting of 221 lines was derived and grown in two trial sites. Six yield traits including number of panicles per plant, number of filled grains per panicle, total number of spikelets per panicle, spikelet fertility, 1 000-grain weight, and grain yield per plant were measured. An SSR marker linkage map was constructed and employed to determine QTLs for yield traits with Windows QTL Cartographer 2.5. QTLs were detected in the target interval for all the traits analyzed except NP, with phenotypic variance explained by a single QTL ranging between 6.3% and 35.2%. Most of the QTLs for yield components acted as additive QTLs, while the three QTLs for grain yield had dominance degrees of 1.65, 0.84, and -0.42, respectively. It was indicated that three or more QTLs for yield traits were located in the target region. The genetic action mode, the direction of the QTL effect, and the magnitude of the QTL effect varied among different QTLs for a given trait, and among QTLs for different traits that were located in the same interval.
基金supported by the National Natural Science Foundation of China(GrantNo.30571062)National Hi-Tech Research and Development Program of China(Grant No.2006AA10Z1E8)the Program of Super Rice from Chinese Agricultural Ministry(Grant No.200906)
文摘The QTL qHUS6 for hull silicon content in rice was previously located on the short arm of rice chromosome 6. By using an F2:3 population segregating in the RM587-RM19784 region harboring qHUS6 in an isogenic background, two QTLs for hull silicon content were detected, of which qHUS6-1 was located in the distal region and qHUS6.2 in the region proximal to the centromere. Three rice plants carrying small heterozygous segments in the target region were selected, of which two covered the qHUS6-1 region and the other covered the qHUS6-2 region. Three F2:3 populations were derived from the selfed seeds of the three plants, respectively. QTL mapping was performed using the two populations segregating in the qHUS6-1 region, and qHUS6-1 was delimited to a 147.0-kb region flanked by the markers RM510 and RM19417. Five groups of F3 lines with different genotypic compositions in the qHUS6-2 region were selected from the other F2-3 population. Two QTLs were separated with two-way ANOVA, of which qHUS6-2a was located in the interval defined by RM19706-RM19795 and qHUS6-2b in the interval RM314-RM19665.
基金supported by the Chinese Super Rice Research Program(200906)the High-Yielding Transgenic Program,China(2008ZX08001-004)the National Natural Science Foundation of China(30571062)
文摘A rice residual heterozygous line (RHL) carrying a heterozygous segment extending from RM111 to RM19784 on the short arm of rice chromosome 6 was selected from a RHL-derived population used previously. The resultant F2:3 population was used to detect quantitative trait loci (QTLs) for three yield traits, the number of spikelets per panicle (NSP), the number of grains per panicle (NGP) and grain yield per plant (GY). Two QTLs for NSP, one QTL for NGP and one QTL for GY were detected, all of which were partially dominant and had the enhancing alleles from the maternal line Zhenshan 97B. Analysis based on the genotypic groups of the markers closely linked to the two QTLs for NSP indicated that they did not interact with each other. Two F2 populations and two near isogenic line (NIL) sets segregating in two sub-regions of interval RM111-RM19784 were developed. The two QTLs for NSP were validated, of which one had major effect and was co-segregated with heading date gene Hdl, and the other had smaller effect and was located in an upper region linked to Hdl. The two regions also showed significant effects on the number of filled grain and grain yield, although the effect on the number of filled grain was less consistent.