Identification Caspian salmon Salmo caspius (Kessler, 1877) and rainbow trout Oncorhynchus mykiss (Walbaum, 1792) by extracting DNA from water (eDNA)

  Proof of species existence in different regions can be useful for studying the migration pattern of the species. The use of non-invasive methods such as eDNA can be very effective in tracking and dispersing and improving the management of water resources and species. In this study, 15 water samples were taken from different areas of the southern Caspian Sea basin. Amino-modified silica-coated magnetic nanoparticles were used to separate DNA from water. In this study, for the first time, the amino magnet method was used to separate environmental DNA from a water sample. DNA of three water samples were properly extracted ,from the water output of Oncorhynchus mykiss farm in Tajan river  in Sari, water samples from salmon cages in Nowshahr and water samples from around Caspian salmon farming cages in Tonekabon were properly examined. The results showed that sample No. 1 was located in the rainbow trout clad and samples No. 2 and 3 were located in the Caspian Sea salmon clad, indicating that the species were properly isolated with amino silicate magnetic nanoparticles and their presence in the aqueous body was confirmed by environmental DNA.