国际植物分子育种最新研究进展

GAP
Yield gap II
5 t/ha

Theoretical Experimental Potential potential Station Farm yield yield
Actual Farm yield
Biological • Variety • Weeds • Pests • Problem soils • Water • Soil fertility Socioeconomic • Costs • Credit • Tradition • Knowledge • Input • Instructions
(Modified from Chaudhary 2000)
Molecular Plant Breeding
Concept Development QTL separating, pyramiding and cloning (Xu 1997) Global view of QTL: rice as a model (Xu 2002) Marker-assisted selection strategies for hybrid rice breeding (Xu 2003) Use of rice as a model for cereal improvement (Xu et al 2005) MAS from publications to practice (Xu & Crouch 2008) Development of SNP-based molecular breeding platforms (Xu et al 2009) Sequence-based molecular breeding (2010)
Information on the presence or absence (and possibly the relative amounts of mutant vs. wild type) of mutations at one or more specific locations Limited or no information about nucleotide positions
Full genome All genomic and sequence and environmental genome-wide factors molecular markers Whole Genome
Strategies
A representative or complete set of genetics and breeding germplasm
The detection of sequence variation, for which DNA sequencing has emerged as the most sensitive and automated approach, forms the basis of all genetic analysis
Bottlenecks in Molecular Breeding
Long Cost-Effective and High Throughput Genotyping Systems Windy Genetic Architecture of Complex Traits Bumpy Molecular Techniques Development and Validation Wrong turns Genotype by Environment Interaction Unexpected blockades Powerful Bioinformatics and Decision Support Tools
Genomic selection, as an example for genomewide selection, is poised to revolutionize plant breeding, because it Uses marker data to predict breeding line performance in one analysis Analyzes the breeding populations directly Includes all markers in the model so that effect estimates are unbiased and small effect QTL can be accounted for
中国农业科学院作物科学研究所 International Maize and Wheat Improvement Center (CIMMYT)
Challenges in Crop Improvement
Maize
Goff and Salmeron 2004 Scientific American 291(2) 42-49
Baidu Nhomakorabea
Components of Whole Genome Strategies
Genotyping-by-Sequencing
The term 'genotyping' describes the genetic characterization of a genome. The genotype analysis is performed to identify mutations that differentiate one individual or strain from another.
Specific Phenotypes Breeding Products
Molecular Plant Breeding: Scale
Population Size
Seed DNA-based genotyping (Gao et al 2008) Selective genotyping (Xu et al 2008; Sun et al 2010) Population sizes in QTL mapping (Sun et al 2010; Xu 2010)
《中国农业科学》创刊50周年暨 第四届世界农业科学前沿高层论坛 August 9-11, 2010, Beijing, China
国际植物分子育种最新研究进展 ——植物分子育种的全基因组策略 Whole Genome Strategies for Molecular Plant Breeding
徐云碧
What Does Whole Genome Mean?
Full genomic sequences Full sequences for all germplasm accessions Markers covering every gene for all the traits High density maps or markers that can be used for high resolution LD mapping to narrow down to each gene or allele High precision phenotyping for all traits measured under multiple environments All environmental factors influencing genes and performance All genes and alleles under selection Strategies for selection on the whole genome levels: all the genes and alleles and their combinations
Population sizes in marker-assisted selection
Molecular Plant Breeding: Scale
Genome Coverage High density SNP genotyping (Lu et al 2009; Farkhari et al 2010) Whole genome resequencing (Lu & Xu et al 2010) Targeted resequencing (exon capturing etc) Marker-assisted recurrent selection (Xu 2010) Genome-wide association study (GWAS) (Xu 2010) Genomic selection
Non-sequencing Methods
Restriction enzyme digestion of PCR products Primer-specific PCR Reverse hybridization of PCR products to probes on nitrocellulose strips Hybridization to microarrays or silicon chips containing thousands of specific probes Cleavage of probes by endonucleases with specific requirements for the tertiary structure of hybrids.
Molecular Breeding for Complex Traits
Phenotype
Genotype
Environment
Whole Genome Strategies Are Required for a Highly Effective Molecular Breeding system
Components of Whole Genome Strategies
Genomewide Selection
Phenotypic selection for stress-prone environments is difficult and slow; Traditional MAS is ineffective for complex traits.
Yield Gap to Be Filled by Plant Breeding
Yield gap 0 17.1 Nontransferable technology Yield gap I Environmental differences For scientists to conceive and breed potential varieties
Molecular Plant Breeding
Y Xu
ISBN: 978 1 84593 392 0 2010 734 pages
• Molecular Breeding Tools: Omics and Arrays • Populations in Genetics and Breeding • Plant Genetic Resources • Molecular Dissection of Complex Traits: Theory • Molecular Dissection of Complex Traits: Practice • Marker Assisted Selection: Theory • Marker Assisted Selection: Practice • Genotype by Environment Interaction • Isolation and Functional Analysis of Genes • Gene Transfer and Genetically Modified Plants • Intellectual Property Rights and Plant Variety Protection • Breeding Informatics • Decision Support Tools