TY - JOUR JF - IJT JO - IJT VL - 11 IS - 2 PY - 2017 Y1 - 2017/1/01 TI - Investigating the Agent of Temperature into Acute Toxicity (LC50 96h) of Edifenphos in Rutilus Frisii Kutum (Kamensky, 1901) TT - N2 - Background: Edifenphos, a kind of organophosphate toxins, is used as agricultural fungicides in rice fields. This study was aimed to investigate the effect of temperature on lethal concentration of exposure to edifenphos on Rutilus frisii kutum (Caspian kutum). Methods: The experiment was carried out in static condition and based on instructions of OECD within 10 d under controlled water physicochemical factors. Dissolved oxygen was fixed on 7-7.5 ppm, pH: 7 to 7.5 and hardness: 200 ppm. Fish were acclimatized in 70*40*30 cm aquarium for 10 d before the test. Treated aquariums with concentrations of 0.01, 0.05, 2, 4, 8, 16 ppm of edifenphos with one control group (no toxic concentration), were performed. In order to test the effect of temperature on acute toxicity, three ranges of 15±1, 20±1 and 25±1 ºC were treated and LC1, LC10, LC30, LC50, LC70, LC90 and LC99 were calculated for 24, 48, 72 and 96 h. The study was carried out in Laboratory of Aquaculture and Fisheries, University of Tehran in 2016. Results: LC50 value in 25 ºC was lower than 20 and 15 ºC. LC50 96h edifenphos for Caspian kutum in 15±1, 20±1 and 25±1 ºC was 3.70, 3.61 and 3.26, respectively. Conclusion: Higher temperature increase toxicity rate of edifenphos and the toxin had a positive temperature coefficient on Caspian kutum. SP - 39 EP - 44 AU - Shahbazi Naserabad, Saeid AU - Mirvaghefi, Alireza AU - Rashidiyan, Ghasem AU - Rostamian, Narges AU - Ghafari Farsani, Hamed AD - MSc of Aquatic Ecology, Young Researchers and Elite Club,Yasooj Branch, Islamic Azad University, Yasooj, Iran. KW - Caspian Kutum KW - Edifenphos KW - Organophosphorus Fungicide KW - Lethal Concentration KW - Temperature UR - http://ijt.arakmu.ac.ir/article-1-572-en.html DO - 10.29252/arakmu.11.2.39 ER -