Allozyme genotype and time to death of mosquitofish,Gambusia affinis(baird and girard), during acute exposure to inorganic mercury

摘要

AbstractGenetic plasticity in a mosquitofish (Gambusia affinisBaird and Girard) population was examined relative to acute mercury toxicity. Genotypes at eight loci (isocitrate dehydrogenase‐1 and ‐2, mannosephosphate isomerase, glucosephosphate isomerase‐2, fumarate hydratase, malate dehydrogenase‐1, leucylglycylglycine peptidase and phenylalanylproline peptidase) were scored using starch gel electrophoresis. Two null hypotheses were tested: (a) time to death does not differ between genotypes at individual loci and (b) time to death does not differ with multiple‐locus heterozygosity. Genotypes at three of the eight loci displayed significant effects on mosquitofish time to death. Multiple‐locus heterozygosity also had a significant effect on time to death. Significant amounts of genetic plasticity were found in a population of mosquitofish with no previous exposure to inorga