Identification and ecological assessment of environmental stressors on fish population using genetic biomarkers

点击翻译按钮获取中文摘要

Difference of genetic biomarkers among fish (Pseudorasbora parvac) populations collected from various sites was examined in order to identify and assess the environmental stressors on each population. First, application of Amplified Fragment Length Polymorphism (AFLP) method to fish was studied for obtaining reliable data on genetic variability among fish populations and measurement of two-dimensional data (strength of fluorescence vs. length of gene fragment) was found to be acceptable for this purpose.The genetic variability measured by the proposed method in Pseudorasbora parvac population which experienced large fish kill in the past was small compared to those taken from other habitats. Also the composition of different genotypes in each population classified by AFLP method was found to be special for those populations that live in sites impacted by special environmental stressors such as isolation or agrochemical impact from agricultural effluent. Furthermore, the pollution by polycyclic aromatic hydrocarbons (PAHs) was found to be related to the composition of different genotypes in each fish population. In other words, higher concentration of PAHs increased the composition of a certain genotype in each fish population. The acute toxicity (50% lethal concentration (LC_<50>) and 50% effective concentration (EC_<50>)) of Pseudorasbora parvac to fluoranthene, which was indicated to be the main stressor among PAHs, was significantly different among the fish populations taken from different habitats. This indicated that tolerance of Pseudorasbora parvac to luoranthene was varied due to the difference of environmental fluoranthene pollution in each habitat.This study showed that genetic variability and genotype measured by AFLP method can be used to identify and assess the environmental stressors to fish population.