LC50-96h concentrations of Pearaschin and Pretilachlor in Caspian Roach Rutilus lacustris (Pallas, 1814)

Caspian roach is one of the most important species of the Caspian Sea. Natural stocks of this species is reduced during last decades due to different causes, including harmful effects of toxins such as herbicides. In the present study, the acute short-term toxicity of Paraschin and Pretilachlor, are used extensively in the northern provinces of the Iran, were studied on Caspian roach (weight: 7-10 g) determining the LC50-96h concentrations of them. The experiments were static and based on the DCEO standard methods for 4 days and the physicochemical parameters of water including pH, dissolved oxygen (DO) and temperature were measured: pH: 8.2-8.8 ; DO: 71-75%; and, T: 17.1-17.4 &. The results showed that the acute toxicity of Pearaschin and Pretilachlor was 1.243 and 2.233 mg.L-1, respectively, and the maximum allowable concentration (MAC Value) of these toxicant was 1.243 and 0.233 mg.L-1, respectively. According to toxicity of different pesticides, Parasin and Pretilachlor toxicant are considered to have middle toxicity for this fish.

Keywords:

Rutilus caspicus , Pearaschin , Pretilachlor.