Study theEffectofColdWaterExtractsofPetroselinum crispumLeavesonCulex pipiensInstars


This study aimed to know the effect of different concentrations of cold water extract of Petroselinum crispum leaves on Culex pipiens instars and findthe half lethal concentration (LC50). The results showed that the third instar of C. pipienswere more effective by cold water extract thanfirst,second, and fourth instarafter 24 hours from exposure to different concentrations (250, 300, 350, 400) mg/l.Results appeared thatthe percentage of mortalities after 24 hours from exposure to cold water extracts were(37, 44, 67, 85) %, (26, 41, 67, 78) %, (42, 65, 77, 92) % and (16, 32, 52, 89) %with LC50 (300), (319), (267) and(333) mg/lfor first, second, third, and fourth instar of C. pipiens respectively. Also, the results didn’t show a significant differentiationin level of probability 0.05,but appeared positive correlation coefficientbetween the percentage of mortalities and the concentrations, and negative correlation coefficient between the percentage of survival and the concentrations.