Genetic erosion in the freshwater snail filopaludina martensi is affected by lead and cadmium

Abstract

This study aims to determine the lead (Pb) and cadmium (Cd) concentrations and genetic variability in the tissues of the freshwater snail Filopaludina martensi. These measures can be biomarkers of environmental quality. The samples were collected over three seasons from five sites around the Ubonrat Dam. The results showed that the average concentrations of Cd and Pb found in the tissue of fresh water snails during the rainy season (0.1040 and 0.0106 μg/g, respectively) were higher than in the winter (0.0566 and 0.0030, respectively) and summer (0.0654 and 0.0059 μg/g, respectively). Random amplified polymorphic DNA (RAPD) was successfully applied to produce 440 total bands used for dendrogram construction and analysis of genetic similarity (S). The dendrogram separated the studied samples by seasons, showing the highest S values of 0.59-0.93 in the Rainy S1-S5 and S2-S3, 0.62-0.83 in the Winter S1-S4 and S1-S2, and 0.64-0.84 in the Summer S1-S5 and S2-S3. The highest S values in the rainy season that are lower values compare to samples from other seasons are those associated with the highest average concentrations of Cd and Pb in the tissues sampled in this season. The metal concentrations are below the standard control level, but they can still affect the genetic material of freshwater snails. © 2014, ALÖKI Kft., Budapest, Hungary.