Genetic variation and population structure of the giant tiger prawn, Penaeus monodon, in Indonesia

Abstract

Seven populations of Penaeus monodon (Aceh, Cilacap, Madura, Bali, Tarakan, Dompu and Sulsel) were sampled between 1995 and 1999 from the coastal waters of Indonesia and screened electrophoretically for genetic variation at 22 loci. All six polymorphic loci ( EST-1*, α-GPD*, GPI*, IDH*, LDH-2* and MDH-2*) were in Hardy–Weinberg equilibrium at all localities. Genetic variability was low. The number of alleles per locus ranged from 1.3 to 1.5 (average=1.4), and the observed heterozygosity ranged from 0.018 to 0.046 (average=0.027). Rogers' genetic distance between population pairs ranged from 0.003 to 0.017 (average 0.008). Significant population differentiation ( F st=0.013, P<0.05) in the total data set reflected the differentiation of the Aceh population from all the others (pairwise F st values ranged from 0.020 to 0.047, P<0.05). Although there was no significant differentiation among the other populations ( F st ranged from 0.003 to 0.005, P>0.05), there was evidence for isolation by distance whether or not the Aceh population was included ( Z=0.79–0.87, P<0.01). Populations clustered into three geographical groups, Aceh in the east, Tarakan and Sulsel from the northern islands, and the other populations from the southern island arc. The groups were generally consistent with regions that would have been in separate sea basins, or isolated sea arms, at past low sea level stands.