Evaluation of Genetic Diversity in and Molecular Genotyping of Asian Wheat Genetic Resources

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Evaluation of genetic diversity in and molecular genotyping of genetic resources of wheat and its relatives were conducted. Modernization of agriculture has produced many modern wheat cultivars adapted with irrigation, chemical nutrition and mechanization, and today supported a huge world food demand. The modernization, however, resulted in loss of genetic diversity, thus we face the limitation of the increased yield and fragility against coming world environment changes. To overcome the problems, the genetic diversity present in wild species and are reconsidered, and the importance of evaluation and utilization of the potential genetic diversity are noticed. The establishment of the evaluation method of such diversity and the elucidation of the evolutionary process which has produced the diversity are also considered to be valuable.The spread of cultivated wheat from its original place to the west and east produced a lot of differentiated local varieties, namely landraces, adapted wit … More h various local climates. Japanese wheat research community have collected wild species and landraces and have long-time conserved them as genetic resources. This research project is a collaborating research formed by researchers who have conserved the genetic resources and investigated genetic diversity or evolutionary processes. In this project approximately 600 cultivated and 700 wild accessions were investigated and the following outcomes were obtained.1. The basic information of morphology, heading trait, salt tolerance and seed dormancy for each accession were evaluated and recorded. The level of diversity was considerably high in both wild and cultivated species.2. Core collections (representative accessions covering whole population) were selected based on DNA marker and AFLP, and methods for conservation were proposed.3. Multiple origins in both domestication and polyploidization processes were revealed, which are clearly contrasted with previous theories.4. The genes controlling or related with heading trait and seed dormancy were identified using DNA marker. Genetic variation among accessions in those genes was revealed. These results enable us to use DNA marker to distinguish variety or to reveal evolutionary process.5. The accessions used in this study and data obtained were registered in National BioResources Project (NBRP) database and free access and easy utilization were enabled. Less