Founder parents have contributed significantly to the improvement of wheat breeding and production. In order to investigate the genetic characteristics of founder parents and widely planted cultivars, Mazhamai(M), Biy...Founder parents have contributed significantly to the improvement of wheat breeding and production. In order to investigate the genetic characteristics of founder parents and widely planted cultivars, Mazhamai(M), Biyumai(B) and six sibling lines(BM1–6) derived from the cross M×B were phenotyped for eight yield-related traits over multiple years and locations and genotyped using the the wheat 90 K single nucleotide polymorphism(SNP) assay. BM4 has been used as a founder parent, and BM1 has been widely planted, whereas BM2, 3, 5, and 6 have not been used extensively for breeding or planting in China. Phenotypic comparisons revealed that BM4 and BM1 displayed a better overall performance than the other sibling lines. BM1 showed higher thousand-grain weight than BM4, whereas BM4 exhibited lower coefficient of variation for most of the yield-related traits across different years and locations, indicating that BM4 was widely adaptable and more stable in different environments. SNP analysis revealed that BM4 and BM1 inherited similar proportions of the M genome but are dissimilar to BM2, 3, 5, and 6. Both BM1 and BM4 have specific alleles that differ from the other BM lines, and most of these alleles are concentrated in specific chromosomal regions that are found to associate with favorable QTLs, these SNPs and their surrounding regions may carry the genetic determinants important for the superior performance of the two lines. But BM4 has more genetic diversity than BM1 with more specific alleles and pleiotropic regions, indicating that the genome of BM4 may be more complex than the other sibling lines and has more favorable gene resources. Our results provide valuable information that can be used to select elite parents for wheat and self-pollinating crop breeding.展开更多
Zhu Zhenheng (courtesy name:Zhu Yanxiu,1281-1358) was from Yiwu County,Zhejiang Province.His family lived near a river named Dan Xi for many generations,hence his sobriquet Old Man Dan Xi,or Mr Dan Xi.Since he was int...Zhu Zhenheng (courtesy name:Zhu Yanxiu,1281-1358) was from Yiwu County,Zhejiang Province.His family lived near a river named Dan Xi for many generations,hence his sobriquet Old Man Dan Xi,or Mr Dan Xi.Since he was intelligent,diligent and eager to learn,he traveled around to visit literary celebrities with the expectation to pass the imperial examination and seek an official position.When he was 36 years old,he heard that Xu Qian,a famous scholar of the Neo-Confucianism came to give lectures in Dongyang County,Zhejiang Province,he soon rushed there to learn from him.1 He kept on study for years and made great progress.But he suffered a reversal of fortune and failed the imperial examinations.At this moment,Xu Qian was badly ill and completely bedridden.One day,when Zhu went to visit him,he said:'I have been ill for a long time,and only those who are skillful in medicine can save me.展开更多
Guo Moruo (Kuo Mojo, 1892-1978), specialist in Chinese history, philologist, writer and social activist. His original name was Kuo Kaizhen and his self-styled name was Shangwu. On November 16 1892, he was born in the ...Guo Moruo (Kuo Mojo, 1892-1978), specialist in Chinese history, philologist, writer and social activist. His original name was Kuo Kaizhen and his self-styled name was Shangwu. On November 16 1892, he was born in the town of Shawan in Leshan County, Sichuan Province.From the autumn.of 1907 to the summer of 1913, he was a pupil at the Jiadingfu Middle School and the展开更多
Since the first International Textile Exhibition created by SPINEXPO in March 2003, Ms. Karine Van Tassel, the founder and organizer of SPINEXPO, dedicates herself to the display of the
Controlled pedigrees and the multi-decade timescale of national crop plant breeding programs offer a unique experimental context for examining how selection affects plant genomes.More than 3000 wheat cultivars have be...Controlled pedigrees and the multi-decade timescale of national crop plant breeding programs offer a unique experimental context for examining how selection affects plant genomes.More than 3000 wheat cultivars have been registered,released,and documented since 1949 in China.In this study,a set of 145 elite cultivars selected from historical points of wheat breeding in China were re-sequenced.A total of 43.75 Tb of sequence data were generated with an average read depth of 17.94x for each cultivar,and more than 60.92 million SNPs and 2.54 million InDels were captured,based on the Chinese Spring RefSeq genome v1.0.Seventy years of breeder-driven selection led to dramatic changes in grain yield and related phenotypes,with distinct genomic regions and phenotypes tar-geted by different breeders across the decades.There are very clear instances illustrating how introduced Italian and otherforeign germplasm was integrated into Chinese wheat programs and reshaped the genomic landscape of local modern cultivars.Importantly,the resequencing data also highlighted significant asymmetric breeding selec-tion among the three sub-genomes:this was evident in both the collinear blocks for homeologous chromosomes and among sets of three homeologous genes.Accumulation of more newly assembled genes in newer cultivars implied the potential value of these genes in breeding.Conserved and extended sharing of linkage disequilibrium(LD)blocks was highlighted among pedigree-related cultivars,in which fewer haplotype differences were detected.Fixation or replacement of haplotypes from founder genotypes after generations of breeding was related to their breeding value.Based on the haplotype frequency changes in LD blocks of pedigree-related cultivars,we propose a strategy for evaluating the breeding value of any given line on the basis of the accumulation(pyramiding)of bene-ficial haplotypes.Collectively,our study demonstrates the influence of "founder genotypes" on the output of breeding efforts over many decades and also suggests that founder genotype perspectives are in fact more dy-namic when applied in the context of modern genomics-informed breeding.展开更多
基金supported by grants from the National Basic Research Program of China(973 Program,2011CB100104)the National Natural Science Foundation of China(31471174)
文摘Founder parents have contributed significantly to the improvement of wheat breeding and production. In order to investigate the genetic characteristics of founder parents and widely planted cultivars, Mazhamai(M), Biyumai(B) and six sibling lines(BM1–6) derived from the cross M×B were phenotyped for eight yield-related traits over multiple years and locations and genotyped using the the wheat 90 K single nucleotide polymorphism(SNP) assay. BM4 has been used as a founder parent, and BM1 has been widely planted, whereas BM2, 3, 5, and 6 have not been used extensively for breeding or planting in China. Phenotypic comparisons revealed that BM4 and BM1 displayed a better overall performance than the other sibling lines. BM1 showed higher thousand-grain weight than BM4, whereas BM4 exhibited lower coefficient of variation for most of the yield-related traits across different years and locations, indicating that BM4 was widely adaptable and more stable in different environments. SNP analysis revealed that BM4 and BM1 inherited similar proportions of the M genome but are dissimilar to BM2, 3, 5, and 6. Both BM1 and BM4 have specific alleles that differ from the other BM lines, and most of these alleles are concentrated in specific chromosomal regions that are found to associate with favorable QTLs, these SNPs and their surrounding regions may carry the genetic determinants important for the superior performance of the two lines. But BM4 has more genetic diversity than BM1 with more specific alleles and pleiotropic regions, indicating that the genome of BM4 may be more complex than the other sibling lines and has more favorable gene resources. Our results provide valuable information that can be used to select elite parents for wheat and self-pollinating crop breeding.
文摘Zhu Zhenheng (courtesy name:Zhu Yanxiu,1281-1358) was from Yiwu County,Zhejiang Province.His family lived near a river named Dan Xi for many generations,hence his sobriquet Old Man Dan Xi,or Mr Dan Xi.Since he was intelligent,diligent and eager to learn,he traveled around to visit literary celebrities with the expectation to pass the imperial examination and seek an official position.When he was 36 years old,he heard that Xu Qian,a famous scholar of the Neo-Confucianism came to give lectures in Dongyang County,Zhejiang Province,he soon rushed there to learn from him.1 He kept on study for years and made great progress.But he suffered a reversal of fortune and failed the imperial examinations.At this moment,Xu Qian was badly ill and completely bedridden.One day,when Zhu went to visit him,he said:'I have been ill for a long time,and only those who are skillful in medicine can save me.
文摘Guo Moruo (Kuo Mojo, 1892-1978), specialist in Chinese history, philologist, writer and social activist. His original name was Kuo Kaizhen and his self-styled name was Shangwu. On November 16 1892, he was born in the town of Shawan in Leshan County, Sichuan Province.From the autumn.of 1907 to the summer of 1913, he was a pupil at the Jiadingfu Middle School and the
文摘Since the first International Textile Exhibition created by SPINEXPO in March 2003, Ms. Karine Van Tassel, the founder and organizer of SPINEXPO, dedicates herself to the display of the
基金the Key Research and Development Program of China(2016YFD0100302)the Central Public-interest Scientific Institution Basal Research Fund(Y2017PT39)the CAAS-Innovation Team Program(CAAS-XTCX2018020).
文摘Controlled pedigrees and the multi-decade timescale of national crop plant breeding programs offer a unique experimental context for examining how selection affects plant genomes.More than 3000 wheat cultivars have been registered,released,and documented since 1949 in China.In this study,a set of 145 elite cultivars selected from historical points of wheat breeding in China were re-sequenced.A total of 43.75 Tb of sequence data were generated with an average read depth of 17.94x for each cultivar,and more than 60.92 million SNPs and 2.54 million InDels were captured,based on the Chinese Spring RefSeq genome v1.0.Seventy years of breeder-driven selection led to dramatic changes in grain yield and related phenotypes,with distinct genomic regions and phenotypes tar-geted by different breeders across the decades.There are very clear instances illustrating how introduced Italian and otherforeign germplasm was integrated into Chinese wheat programs and reshaped the genomic landscape of local modern cultivars.Importantly,the resequencing data also highlighted significant asymmetric breeding selec-tion among the three sub-genomes:this was evident in both the collinear blocks for homeologous chromosomes and among sets of three homeologous genes.Accumulation of more newly assembled genes in newer cultivars implied the potential value of these genes in breeding.Conserved and extended sharing of linkage disequilibrium(LD)blocks was highlighted among pedigree-related cultivars,in which fewer haplotype differences were detected.Fixation or replacement of haplotypes from founder genotypes after generations of breeding was related to their breeding value.Based on the haplotype frequency changes in LD blocks of pedigree-related cultivars,we propose a strategy for evaluating the breeding value of any given line on the basis of the accumulation(pyramiding)of bene-ficial haplotypes.Collectively,our study demonstrates the influence of "founder genotypes" on the output of breeding efforts over many decades and also suggests that founder genotype perspectives are in fact more dy-namic when applied in the context of modern genomics-informed breeding.
