The genotoxic effects of quinalphos(QP)were evaluated in the erythrocytes of Cyprinus carpio using the comet,micronucleus,and nuclear abnormality assays.The 96 h LC_(50) value of quinalphos,estimated by static renewal...The genotoxic effects of quinalphos(QP)were evaluated in the erythrocytes of Cyprinus carpio using the comet,micronucleus,and nuclear abnormality assays.The 96 h LC_(50) value of quinalphos,estimated by static renewal system,was 10.9µL/L.On the basis of the LC_(50) value,two sublethal concentrations(1.09 and 2.18µL/L)of the compound were used together with cyclophosphamide(5 mg/L)as the positive control.The fish were exposed for 35 d,and sampling was done at the end of 7,14,21,28,and 35 d.Our results reveal a significant dose-dependent increase in the frequencies of DNA strand breaks,micronucleus,and nuclear abnormalities.Similar responses were also observed in fish exposed to the positive genotoxin cyclophosphamide.The collective findings demonstrated that quinalphos exerts a genotoxic effect on C.carpio.The results further confirmed that the comet,micronucleus,and nuclear abnormality assays are useful tools in determining the potential genotoxicity of pesticides towards aquatic organisms.展开更多
The effects of monocrotophos and quinalphos on population and nitrogen-fixing activity of Azospirillum sp.in four agricultural soils were determined in a laboratory study.Concentrations of the two insecticides up to a...The effects of monocrotophos and quinalphos on population and nitrogen-fixing activity of Azospirillum sp.in four agricultural soils were determined in a laboratory study.Concentrations of the two insecticides up to a 5 kg ha^(-1)level were either stimulatory or innocuous to the popula- tion of Azospirillum in the soils.Four successive applications of the insecticides to soils resulted in a significant increase in the population density.Cultures of Azospirillum sp.,isolated from insecticide-treated soils,exhibited greater nitrogen-fixing activity.Three consecutive subcultur- ings of the isolates from insecticide-treated soils had no effect on their nitrogen-fixing activity.1989 Academic Press,Inc.展开更多
基金The author(D.HEMALATHA)wish to thank UGC,New Delhi for providing grant of Basic Science Research Fellowship(BSR)(No.F.7-24/2007).
文摘The genotoxic effects of quinalphos(QP)were evaluated in the erythrocytes of Cyprinus carpio using the comet,micronucleus,and nuclear abnormality assays.The 96 h LC_(50) value of quinalphos,estimated by static renewal system,was 10.9µL/L.On the basis of the LC_(50) value,two sublethal concentrations(1.09 and 2.18µL/L)of the compound were used together with cyclophosphamide(5 mg/L)as the positive control.The fish were exposed for 35 d,and sampling was done at the end of 7,14,21,28,and 35 d.Our results reveal a significant dose-dependent increase in the frequencies of DNA strand breaks,micronucleus,and nuclear abnormalities.Similar responses were also observed in fish exposed to the positive genotoxin cyclophosphamide.The collective findings demonstrated that quinalphos exerts a genotoxic effect on C.carpio.The results further confirmed that the comet,micronucleus,and nuclear abnormality assays are useful tools in determining the potential genotoxicity of pesticides towards aquatic organisms.
文摘The effects of monocrotophos and quinalphos on population and nitrogen-fixing activity of Azospirillum sp.in four agricultural soils were determined in a laboratory study.Concentrations of the two insecticides up to a 5 kg ha^(-1)level were either stimulatory or innocuous to the popula- tion of Azospirillum in the soils.Four successive applications of the insecticides to soils resulted in a significant increase in the population density.Cultures of Azospirillum sp.,isolated from insecticide-treated soils,exhibited greater nitrogen-fixing activity.Three consecutive subcultur- ings of the isolates from insecticide-treated soils had no effect on their nitrogen-fixing activity.1989 Academic Press,Inc.
