Quantification of genetic diversity at allozyme loci

Starch gel electrophoresis provides a powerful and cost-effective assay of genetic variation in plant populations and species. Allozyme loci are typically single-gene traits that assort independently and are codominant. Sample sizes of 30-50 individuals surveyed at 10-20 polymorphic loci will adequately characterize the genetic diversity in a population and indicate how genetic diversity is partitioned among populations. Parameters that should be reported are the percentage of polymorphic loci (P), mean number of alleles per polymorphic loci (AP), expected heterozygosity (genetic diversity, H-e), Nei's G(ST), genetic identity (I), and genetic distance (D). Examples are provided, and statistical tests of parameter estimates are summarized.