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
The genetic diversity and relationship among 40 elite barley varieties were analyzed based on simple sequence repeat （SSR） genotyping data. The amplified fragments from SSR primers were highly polymorphic in the bad...The genetic diversity and relationship among 40 elite barley varieties were analyzed based on simple sequence repeat （SSR） genotyping data. The amplified fragments from SSR primers were highly polymorphic in the badey accessions investigated. A total of 85 alleles were detected at 35 SSR loci, and allelic variations existed at 29 SSR loci. The allele number per locus ranged from 1 to 5 with an average of 2.4 alleles per locus detected from the 40 badey accessions. A cluster analysis based on the genetic similarity coefficients was conducted and the 40 varieties were classified into two groups. Seven malting barley varieties from China fell into the same subgroup. It was found that the genetic diversity within the Chinese malting barley varieties was narrower than that in other barley germplasm sources, suggesting the importance and feasibility of introducing elite genotypes from different origins for malting barley breeding in China.展开更多
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Project supported by the National Natural Science Foundation of China (Nos. 30700485 and 30771333)the Zhejiang Provincial Natural Science Foundation (No. Y306641),China
文摘The genetic diversity and relationship among 40 elite barley varieties were analyzed based on simple sequence repeat （SSR） genotyping data. The amplified fragments from SSR primers were highly polymorphic in the badey accessions investigated. A total of 85 alleles were detected at 35 SSR loci, and allelic variations existed at 29 SSR loci. The allele number per locus ranged from 1 to 5 with an average of 2.4 alleles per locus detected from the 40 badey accessions. A cluster analysis based on the genetic similarity coefficients was conducted and the 40 varieties were classified into two groups. Seven malting barley varieties from China fell into the same subgroup. It was found that the genetic diversity within the Chinese malting barley varieties was narrower than that in other barley germplasm sources, suggesting the importance and feasibility of introducing elite genotypes from different origins for malting barley breeding in China.
