Exploiting genetic diversity among unadapted wheat landraces from different geographical origins revealed by SSRs
Dreisigacker, S.
Exploiting genetic diversity among unadapted wheat landraces from different geographical origins revealed by SSRs - 2007 - p. 14 - Printed
Abstract only
Over several thousand years, landraces of hexaploid wheat have developed under a variety of different edaphic and climatic environments. This has led to the evolution of a large number of ecotypes adapted to specific local environments, an important source of genetic variation in wheat. Landraces have been characterized phenotypically and found to contain good levels of resistance to pests such as stem rust, leaf rust, or Russian wheat aphid and for tolerance to abiotic stresses like heat, and these have been used in the CIMMYT wheat improvement program. At the molecular level, considerable diversity indicates new variation that may be tapped for continued wheat improvement in the future. Molecular diversity can be used to determine relationships between accessions, and to select diverse core subsets for further phenotypic characterization. In this study, five hundred hexaploid wheat landraces from over 30 countries were analyzed with 35 SSRs. Substantial levels of genetic variation was found in the selected materials. It was clearly demonstrated that genetic differentiation was closely correlated with geographical origin. The accessions were combined into groups of European, Asian or American origin. Differences between clusters of accessions were mainly defined by differences in the frequency of the SSR defined alleles.
English
Exploiting genetic diversity among unadapted wheat landraces from different geographical origins revealed by SSRs - 2007 - p. 14 - Printed
Abstract only
Over several thousand years, landraces of hexaploid wheat have developed under a variety of different edaphic and climatic environments. This has led to the evolution of a large number of ecotypes adapted to specific local environments, an important source of genetic variation in wheat. Landraces have been characterized phenotypically and found to contain good levels of resistance to pests such as stem rust, leaf rust, or Russian wheat aphid and for tolerance to abiotic stresses like heat, and these have been used in the CIMMYT wheat improvement program. At the molecular level, considerable diversity indicates new variation that may be tapped for continued wheat improvement in the future. Molecular diversity can be used to determine relationships between accessions, and to select diverse core subsets for further phenotypic characterization. In this study, five hundred hexaploid wheat landraces from over 30 countries were analyzed with 35 SSRs. Substantial levels of genetic variation was found in the selected materials. It was clearly demonstrated that genetic differentiation was closely correlated with geographical origin. The accessions were combined into groups of European, Asian or American origin. Differences between clusters of accessions were mainly defined by differences in the frequency of the SSR defined alleles.
English