期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2009
卷号：106
期号：23
页码：9519-9524
DOI：10.1073/pnas.0904152106
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The continuous improvement of crop plants is essential for agriculture in the coming decades and relies on the use of genetic variability through breeding. However, domestication and modern breeding have reduced diversity in the crop germplasm. Global gene banks conserve diversity, but these resources remain underexplored owing to a lack of efficient strategies to isolate important alleles. Here we describe a large-scale allele-mining project at the molecular level. We first selected a set of 1,320 bread wheat landraces from a database of 16,089 accessions, using the focused identification of germplasm strategy. On the basis of a hierarchical selection procedure on this set, we then isolated 7 resistance alleles of the powdery mildew resistance gene Pm3, doubling the known functional allelic diversity at this locus. This targeted approach for molecular utilization of gene bank accessions reveals landraces as a rich resource of new functional alleles. This strategy can be implemented for other studies on the molecular diversity of agriculturally important genes, as well as for molecular breeding.
