An Eight-Parent Multiparent Advanced Generation Inter-Cross Population for Winter-Sown Wheat: Creation, Properties, and Validation

MAGIC populations represent one of a new generation of crop genetic mapping resources combining high genetic recombination and diversity. We describe the creation and validation of an eight-parent MAGIC population consisting of 1091 F7 lines of winter-sown wheat (Triticum aestivum L.). Analyses based on genotypes from a 90,000-single nucleotide polymorphism (SNP) array find the population to be well-suited as a platform for fine-mapping quantitative trait loci (QTL) and gene isolation. Patterns of linkage disequilibrium (LD) show the population to be highly recombined; genetic marker diversity among the founders was 74% of that captured in a larger set of 64 wheat varieties, and 54% of SNPs segregating among the 64 lines also segregated among the eight founder lines. In contrast, a commonly used reference bi-parental population had only 54% of the diversity of the 64 varieties with 27% of SNPs segregating. We demonstrate the potential of this MAGIC resource by identifying a highly diagnostic marker for the morphological character "awn presence/absence" and independently validate it in an association-mapping panel. These analyses show this large, diverse, and highly recombined MAGIC population to be a powerful resource for the genetic dissection of target traits in wheat, and it is well-placed to efficiently exploit ongoing advances in phenomics and genomics. Genetic marker and trait data, together with instructions for access to seed, are available at http://www.niab.com/MAGIC/.

[1]  W. Powell,et al.  Methods for linkage disequilibrium mapping in crops. , 2007, Trends in plant science.

[2]  Gary A. Churchill,et al.  Ten Years of the Collaborative Cross , 2012, G3: Genes | Genomes | Genetics.

[3]  J. Garner,et al.  Reanalyses of the historical series of UK variety trials to quantify the contributions of genetic and environmental factors to trends and variability in yield over time , 2010, Theoretical and Applied Genetics.

[4]  J. Cockram,et al.  Segmental chromosomal duplications harbouring group IV CONSTANS-like genes in cereals. , 2010, Genome.

[5]  John H. Doonan,et al.  Challenges of Crop Phenomics in the Post-genomic Era , 2016 .

[6]  W. Powell,et al.  From mutations to MAGIC: resources for gene discovery, validation and delivery in crop plants. , 2008, Current opinion in plant biology.

[7]  Kiyoaki Kato,et al.  RFLP mapping of the three major genes, Vrn1, Q and B1, on the long arm of chromosome 5A of wheat , 1998, Euphytica.

[8]  Meng Li,et al.  Genetics and population analysis Advance Access publication July 13, 2012 , 2012 .

[9]  S. Tanksley,et al.  Microprep protocol for extraction of DNA from tomato and other herbaceous plants , 1995, Plant Molecular Biology Reporter.

[10]  H. Bariana,et al.  Identification and characterization of stripe rust resistance gene Yr34 in common wheat , 2006, Theoretical and Applied Genetics.

[11]  Andrew W George,et al.  A multiparent advanced generation inter-cross population for genetic analysis in wheat. , 2012, Plant biotechnology journal.

[12]  D. Balding,et al.  Genome-wide association mapping to candidate polymorphism resolution in the unsequenced barley genome , 2010, Proceedings of the National Academy of Sciences.

[13]  Xuehui Huang,et al.  An-1 Encodes a Basic Helix-Loop-Helix Protein That Regulates Awn Development, Grain Size, and Grain Number in Rice[C][W][OPEN] , 2013, Plant Cell.

[14]  M. Soller,et al.  Advanced intercross lines, an experimental population for fine genetic mapping. , 1995, Genetics.

[15]  J. Cockram,et al.  PCR‐Based Markers Diagnostic for Spring and Winter Seasonal Growth Habit in Barley , 2009 .

[16]  F. Salamini,et al.  Catalogue of gene symbols for wheat , 1998 .

[17]  Susan McCouch,et al.  Multi-parent advanced generation inter-cross (MAGIC) populations in rice: progress and potential for genetics research and breeding , 2013, Rice.

[18]  D. Bates,et al.  Linear Mixed-Effects Models using 'Eigen' and S4 , 2015 .

[19]  A. E. Watkins,et al.  Variation and genetics of the awn inTriticum , 1940, Journal of Genetics.

[20]  J. Snape,et al.  Dissecting gene × environmental effects on wheat yields via QTL and physiological analysis , 2007, Euphytica.

[21]  J. Cockram,et al.  Evaluation of diagnostic molecular markers for DUS phenotypic assessment in the cereal crop, barley (Hordeum vulgare ssp. vulgare L.) , 2012, Theoretical and Applied Genetics.

[22]  P. Ingvarsson,et al.  Using association mapping to dissect the genetic basis of complex traits in plants. , 2010, Briefings in functional genomics.

[23]  David J Balding,et al.  Multiple Quantitative Trait Analysis Using Bayesian Networks , 2014, Genetics.

[24]  R. Mott,et al.  A Multiparent Advanced Generation Inter-Cross to Fine-Map Quantitative Traits in Arabidopsis thaliana , 2009, PLoS genetics.

[25]  C. Feuillet,et al.  Sequence-based marker development in wheat: advances and applications to breeding. , 2012, Biotechnology advances.

[26]  J. Anderson,et al.  Genome-wide comparative diversity uncovers multiple targets of selection for improvement in hexaploid wheat landraces and cultivars , 2013, Proceedings of the National Academy of Sciences.

[27]  A. C. Collins,et al.  A method for fine mapping quantitative trait loci in outbred animal stocks. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[28]  H. Kanamori,et al.  A SHORT INTERNODES (SHI) family transcription factor gene regulates awn elongation and pistil morphology in barley , 2012, Journal of experimental botany.

[29]  W. Powell,et al.  The genetic diversity of UK, US and Australian cultivars of Triticum aestivum measured by DArT markers and considered by genome , 2008, Theoretical and Applied Genetics.

[30]  Bevan Emma Huang,et al.  R/mpMap: a computational platform for the genetic analysis of multiparent recombinant inbred lines , 2011, Bioinform..

[31]  P. Donnelly,et al.  Replicating genotype–phenotype associations , 2007, Nature.