marker-assisted selection in wheat - ictsd

376Marker-assisted selection – Current status and future perspectives in crops, livestock, forestry and fishFigure 4The Genolyptus project – from phenotypes to genotypes in an integrated way√√√√Growth , floweringFIELD EXPERIMENTS24 connected full-sib familiesamong divergent treesLarge progeny sizes (> 1200individuals)Partial clonal replicationSeveral genetic backgrounds andlocationsPHYSICAL MAPPINGWOODPROPERTIESPHENOTYPESLINKAGEAND ASSOCIATIONMAPPINGDisease resistanceGENE DISCOVERY√ Several cDNA libraries√ EST sequencing√ Candidate genes√ SSRs and SNPs in cDNAs√ Full length cDNA database√ Bioinformatics: data mining√ Microarrays and SAGE√ SNP and association mapping√√√√√BAC libraryAnchoring with genetic mapComplete physical mapBAC end sequencingEST mappingFull gene and promoteridentificationQTL & candidate genesGENES & LINKEDMARKERS√√√QTL MAPPINGGenetic map construction inmultiple familiesGenome scan with 200+microsats in multiplexesOutbred QTL modelsSource: Grattapaglia, 2003.Eucalyptus, coupled with the translationof knowledge into improved tree breedingtechnologies.This programme relies heavily on thedevelopment of aligned R&D efforts ingenetic resources, genomics and molecularbreeding (Figure 4). It mobilizes capacitiesand infrastructure in constructing physicalmaps, developing expressed sequencetag (EST) databases, generating a databaseof expression profiling of genes that controlkey traits and developing methods forMAS for traits of high heritability in woodformation. Also, the network develops acapacity-building and training programmefor professionals in universities and forestrycompanies, targeting the integrationof genetics, genomics and breeding effortsof Eucalyptus.The rationale of the network is based onthe understanding that, even with the morepowerful tools allowing a much more globaland integrated view of genetic processes,genomics will only succeed in contributingto the development of improved eucalyptif it is deeply interconnected with intensivefieldwork and creative breeding. TheGenolyptus project therefore differs fromother plant genome initiatives in the intensity,refinements and scope of the effortdevoted to field experiments to generatethe diversity of phenotypes necessary tostudy gene function. Quantitative trait loci(QTL) detection, the development of SNPhaplotypes for association mapping andphysical mapping will link the phenotypesto genes that control processes of woodformation that define industrial level traits(Grattapaglia, 2003).A key feature of the Genolyptus networkis its pre-competitive nature. Theresearch programme was designed collaborativelywith no immediate intention ofmarketing its results, even although its