Response of Genotypes of Hyalella azteca to Zinc Toxicity
Uložené v:
| Názov: | Response of Genotypes of Hyalella azteca to Zinc Toxicity |
|---|---|
| Autori: | Eisenhauer, J. B., Sullivan, Karen Brown, Lydy, Michael J. |
| Zdroj: | Bulletin of Environmental Contamination and Toxicology. 63:125-132 |
| Informácie o vydavateľovi: | Springer Science and Business Media LLC, 1999. |
| Rok vydania: | 1999 |
| Predmety: | Time Factors, Genotype, Crustacea/genetics, Spectrophotometry, Atomic, Zinc/toxicity, Zinc/analysis, Fresh Water, Atomic, Survival Analysis, 01 natural sciences, Lethal Dose 50, Zinc, Fresh Water/analysis, Spectrophotometry, Crustacea, Animals, Alleles, 0105 earth and related environmental sciences |
| Popis: | Toxicity tests are most frequently conducted on organisms derived from laboratory cultures that have been reared for many generations following standardized protocols. The restricted density of laboratory populations and the possibility of occasional population crashes increases the probability that random genetic drift and inbreeding may decrease genetic variation of the culture below that typically found in natural populations of the species. Likewise, isolation of organisms in different laboratories may contribute to significant genetic differentiation among culture populations. For example, Duan et al. (1997) present evidence for extensive genetic differentiation among laboratory cultures of the amphipod Hyalella azteca, a species routinely used in toxicity testing. Duan et al. (1997) suggest consistency among toxicity tests performed in different laboratories can only be assured with a knowledge of the genetic similarity among cultures. The recommendation for monitoring the genetic structure of laboratory populations is further supported by the results of studies that indicate, for some species, differential tolerance of genotypes to an environmental stressor (e.g. Sullivan and Lydy 1998, Guttman 1994). In the situation where certain genotypes are more resistant to a particular stressor, using a culture that is dominated by the resistant genotype may underestimate the toxic effect of a contaminant. Similarly, the inclusion of a greater number of sensitive genotypes in a test may overestimate toxicity. This experiment was conducted to test the null hypothesis that no difference in tolerance to zinc contamination would be noted among distinct genotypes of H. azteca obtained from a single laboratory source. Zinc was selected as the contaminant in this study because much of the focus in research conducted to examine genotypic differences in stressor susceptibility has centered on heavy metals. Although zinc is an essential trace element for organisms, it can , at high concentrations, act as an environmental contaminant, particularly in aquatic ecosystems that receive mining effluent. Hyallela azteca was chosen because the research of Duan et al. (1997) indicated genetic differentiation among laboratory cultures and this species is commonly used in ecotoxicological studies. |
| Druh dokumentu: | Article |
| ISSN: | 1432-0800 0007-4861 |
| DOI: | 10.1007/s001289900957 |
| Prístupová URL adresa: | https://pubmed.ncbi.nlm.nih.gov/10423493 https://link.springer.com/article/10.1007/s001289900957 https://www.ncbi.nlm.nih.gov/pubmed/10423493 https://core.ac.uk/display/59207606 https://pubmed.ncbi.nlm.nih.gov/10423493/ |
| Rights: | Springer TDM |
| Prístupové číslo: | edsair.doi.dedup.....d2d10f3aea397c1be76f0dac0a2906c8 |
| Databáza: | OpenAIRE |
Full Text Finder 
Nájsť tento článok vo Web of Science | Abstrakt: | Toxicity tests are most frequently conducted on organisms derived from laboratory cultures that have been reared for many generations following standardized protocols. The restricted density of laboratory populations and the possibility of occasional population crashes increases the probability that random genetic drift and inbreeding may decrease genetic variation of the culture below that typically found in natural populations of the species. Likewise, isolation of organisms in different laboratories may contribute to significant genetic differentiation among culture populations. For example, Duan et al. (1997) present evidence for extensive genetic differentiation among laboratory cultures of the amphipod Hyalella azteca, a species routinely used in toxicity testing. Duan et al. (1997) suggest consistency among toxicity tests performed in different laboratories can only be assured with a knowledge of the genetic similarity among cultures. The recommendation for monitoring the genetic structure of laboratory populations is further supported by the results of studies that indicate, for some species, differential tolerance of genotypes to an environmental stressor (e.g. Sullivan and Lydy 1998, Guttman 1994). In the situation where certain genotypes are more resistant to a particular stressor, using a culture that is dominated by the resistant genotype may underestimate the toxic effect of a contaminant. Similarly, the inclusion of a greater number of sensitive genotypes in a test may overestimate toxicity. This experiment was conducted to test the null hypothesis that no difference in tolerance to zinc contamination would be noted among distinct genotypes of H. azteca obtained from a single laboratory source. Zinc was selected as the contaminant in this study because much of the focus in research conducted to examine genotypic differences in stressor susceptibility has centered on heavy metals. Although zinc is an essential trace element for organisms, it can , at high concentrations, act as an environmental contaminant, particularly in aquatic ecosystems that receive mining effluent. Hyallela azteca was chosen because the research of Duan et al. (1997) indicated genetic differentiation among laboratory cultures and this species is commonly used in ecotoxicological studies. |
|---|---|
| ISSN: | 14320800 00074861 |
| DOI: | 10.1007/s001289900957 |