Isozyme analysis on the populations ofRuditapes philippinarum

Horizontal starch gel electrophoresis was used to investigate the genetic structure of six populations of Ruditapes philippinarum in the coast of China. Seven enzymes revealed eleven putative loci, and seven of them were polymorphic, PGM, MDH-1, MDH-3, LAP-1, LAP-2, MPI-1 and MPI-2. The proportions of polymorphic loci of R. philippinarum populations varied from 0.454 5 to 0.636 4. The values of observed and expected heterozygosities were from 0.039 4 to 0.154 5 and from 0.1111 to 0.238 5, respectively. Nei's genetic distance varied from 0.003 3 to 0.025 3 with an average of 0.013 5. It is suggested that the genetic diversity of R. philippinarum was high.