RFLP diversity and relationships among traditional European maize populations

Abstract

Given the large extent of hybrid cultivation, the importance of conserving the diversity of crop genetic resources has given birth to numerous collections of old races. In the present paper, we conduct a molecular characterisation of a large collection of 488 European maize populations using the bulk RFLP analysis. The analysis of 23 RFLP loci showed a high allelic richness of 11.5 alleles per locus. Populations from eastern Europe (Poland, Austria, Germany, etc.) showed the lowest genetic diversity, a lower number of unique alleles and a higher percentage of fixed loci than populations from southern Europe. In fact, genetic diversity appeared higher in Southern regions where the first maize populations are thought to have been introduced. Molecular classification based on Rogers' distance (i.e. alleles frequencies) allowed us to distinguish three main clusters which were highly consistent with geographic origins. A Northeastern cluster grouped together early or intermediate populations from Northeastern countries and the Balkans, a southeastern cluster joined late and partially dent populations from Greece and Italy, and, a southwestern cluster was made up of early flint populations from northern Spain, Portugal and the Pyrenees. A correlation between allelic frequencies at some loci and latitude and/or longitude was observed. Such tendencies may reflect the direction of gene flow between different races of maize: for instance, North American (Northern flint) and Caribbean populations were introduced, respectively, to northern and southern Europe, in the past.

Molecular Markers for the Classification of Switchgrass (Panicum virgatum L.) Germplasm and to Assess Genetic Diversity in Three Synthetic Switchgrass Populations

“…In the present study, heterologous RFLP markers were used to estimate polymorphism and genetic diversity within and between three synthetic cultivars, 'Alamo', 'Kanlow', and 'Summer' widely used in biomass-energy breeding programs. RFLP markers have been used in studies of genetic diversity in several grasses including rice (Oryza sativa L.) (Zhang et al 1992), maize (Gauthier et al 2002), and pearl millet (Pennisetum glaucum L.) (Bhattacharjee et al 2002). Even though they are more laborious and time consuming compared to RAPD and AFLP (Karp et al 1996), RFLPs are locus specific and more repeatable.…”

Genetic diversity of new maize hybrids based on SSR markers as compared with other molecular and biochemical markers

“…However, the morphological differences are usually determined by a small number of genes and may not be representative of genetic divergence in the entire genome (Singh et al 1999;Brown-Guedira et al 2000). Compared with morphological variation, molecular and biochemical polymorphism is generally considered more informative (Gauther et al 2002). Molecular genetic techniques can be applied for the evaluation of genetic diversity and as a complementary strategy to traditional approaches in the conservation and utilization of plant genetic resources (Gauther et al 2002;Ghebru et al 2002).…”

Maize introduction into Europe: the history reviewed in the light of molecular data

“…Furthermore, a simplified Bulk-RFLP method ) was developed in order to analyse large sets of maize populations. The analysis of a representative sample of the French INRA-PROMAIS gene bank was performed first , followed by the analysis of more than 450 European maize populations (Rebourg et al 2001;Gauthier et al 2002). These studies lead to a classification of populations in genetic groups and showed a clear differentiation according to latitude, suggesting several independent introductions of maize in Europe.…”