Genetic diversity and structure in a natural Elymus caninus population from Denmark based on microsatellite and isozyme analyses

Genetic diversity in a natural Elymus caninus population from Denmark was a ssessed using isozyme and microsatellite markers. A total of 119 individual s from 46 maternal plants were assayed. Microsatellite loci are shown to di splay higher levels of variation than isozyme loci. The mean number of alle les per locus was 1.04 for isozymes and 1.38 for microsatellites. The perce ntage of polymorphic loci for isozymes and microsatellites was 4.7% and 23. 6% across the maternal plant, respectively. The genetic diversity at popula tion level was 0.1 for isozymes, and 0.63 for microsatellites. The mean gen etic diversity at maternal plant level was 0.027 for isozyme loci and 0.117 for microsatellite loci. The average of total allozyme diversity (HT) was 0.22. The average of total microsatellite diversity was 0.56. Isozyme and m icrosatellite variation showed the same pattern of differentiation between maternal plants. More than 75% total genetic diversity was found among mate rnal plants. About 25% total genetic diversity was detected within maternal plants. Ten (22.7%) maternal plants produced heterozygous offspring at all ozyme loci, and 30 (68.2%) maternal plants gave heterozygous offspring at m icrosatellite loci. Both types of markers revealed a relatively high geneti c diversity in this population.