GENETIC-STRUCTURE OF A POPULATION OF THE CLONAL GRASS SETARIA-INCRASSATA

We studied the genetic structure of a population of the clonal grass Setaria incrassata using isozyme electrophoresis to determine the extent of clone and gene diversity within and between three spatially isolated Setaria patches. High clone diversity and an even distribution of genets, which covered less than 0.25 m2 on average, indicated that patch formation was dominated by propagation from seed. Gene diversity was high within the population and there was little genetic differentiation between patches. High levels of heterozygosity and polymorphism and strongly negative fixation indices indicated extensive recombination through outbreeding, despite the low number of alleles per locus. The synergistic effects of vegetative and sexual propagation may have contributed towards the unexpectedly high genetic diversity of this population. Genetic diversity in clonal populations may be preserved in the genotypes of clones and may therefore be increased by even rare recombination events. Copyright © 1993, Wiley Blackwell. All rights reserved