monocrotophos and quinalphos

An experiment was conducted under laboratory conditions to investigate the effect of four organophosphate insecticides, viz. monocrotophos, profenophos, quinalphos and triazophos at their field application rates (0.75, 1.0, 0.5 and 0.6 kg a.i.ha(-1), respectively), on the growth and activities of phosphate solubilizing microorganisms in relation to availability of insoluble phosphates in the Gangetic alluvial soil of West Bengal, India. The proliferation of phosphate solubilizing microorganisms was highly induced with profenophos (38.3%), while monocrotophos exerted maximum stimulation (20.8%) towards the solubility of insoluble phosphates in soil. The phosphatase activities of the soil (both acid phosphatase and alkaline phosphatase) were significantly increased due to the incorporation of the insecticides in general, and the augmentation was more pronounced with quinalphos (43.1%) followed by profenophos (27.6%) for acid phosphatase, and with monocrotophos (25.2%) followed by profenophos (16.1%) for alkaline phosphatase activity in soil. The total phosphorus was highly retained by triazophos (19.9%) followed by monocrotophos (16.5%), while incorporation of triazophos and quinalphos manifested greater availability of water soluble phosphorus in soil.

Topics: Analysis of Variance; Bacteria; India; Insecticides; Monocrotophos; Organophosphates; Organothiophosphorus Compounds; Pesticide Residues; Phosphates; Phosphoric Monoester Hydrolases; Phosphorus; Soil; Soil Microbiology; Soil Pollutants; Solubility

Clinical scoring systems are used to predict mortality rate in hospitalized patients. Their utility in organophosphate (OP) poisoning has not been well studied.. In this retrospective study of 396 patients, we evaluated the performance of the Acute Physiology and Chronic Health Evaluation (APACHE) II score, the Simplified Acute Physiology Score (SAPS) II, Mortality Prediction Model (MPM) II, and the Poisoning Severity Score (PSS). Demographic, laboratory, and survival data were recorded. Receiver operating characteristic (ROC) curves were generated, and the area under the curve (AUC) was calculated to study the relationship between individual scores and mortality rate.. The mean (standard deviation) age of the patients was 31.4 (12.7) years, and at admission, their pseudocholinesterase (median, interquartile) level was 317 (222-635) U/L. Mechanical ventilation was required in 65.7% of the patients and the overall mortality rate was 13.1%. The mean (95% confidence interval) scores were as follows: APACHE-II score, 16.4 (15.5-17.3); SAPS-II, 34.4 (32.5-36.2); MPM-II score, 28.6 (25.7-31.5); and PSS, 2.4 (2.3-2.5). Overall, the AUC for mortality was significantly higher for APACHE-II (0.77) and SAPS-II (0.77) than the PSS (0.67). When patients were categorized, the AUCs were better for WHO Class II (0.71-0.82) than that for Class I compounds (0.60-0.66). For individual compounds, the AUC for APACHE-II was highest in quinalphos (0.93, n = 46) and chlorpyrifos (0.86, n = 38) and lowest in monocrotophos (0.60, n = 63). AUCs for SAPS-II and MPM-II were marginally but not significantly lower than those for APACHE-II. The PSS was generally a poorer discriminator compared to the other scoring systems across all categories.. In acute OP poisoning, the generic scoring systems APACHE-II and SAPS-II outperform the PSS. These tools may be used to predict the mortality rate in OP poisoning.

Topics: Adult; APACHE; Chlorpyrifos; Cholinesterase Inhibitors; Cohort Studies; Health Status Indicators; Hospitals, Religious; Hospitals, University; Humans; India; Insecticides; Medical Records; Monocrotophos; Organophosphate Poisoning; Organothiophosphorus Compounds; Prognosis; Retrospective Studies; ROC Curve; Severity of Illness Index; Young Adult

Interaction effects of the insecticides monocrotophos and quinalphos (organophosphates), and cypermethrin (pyrethroid), on microbial activities in two agricultural soils-black vertisol soil and red alfinsol soil were tested for 30 days under laboratory conditions. Individual application of the three insecticides at 5, 10 and 25microg g(-1) to the soil distinctly enhanced the activities of cellulase and amylase. Insecticide combinations involving monocrotophos or quinalphos with cypermethrin yielded synergistic, antagonistic and additive interaction effects on both enzymes in the soils. At lower levels, 5 and 10microg g(-1), the insecticides in combination interacted additively or synergistically toward both enzymes. But, both combinations at the highest level of 25microg g(-1) exhibited an antagonistic interaction, with a reduction in enzyme activities to a level lower than that of the control. Interaction effects of insecticides in combinations on two enzyme activities in both soils were related to populations of cellulolytic and amylolytic organisms in soils under the impact of combination of insecticides. These interaction responses were persistent even for 30 days.

Topics: Amylases; Bacteria; Bacterial Proteins; Cellulase; Dose-Response Relationship, Drug; Down-Regulation; Drug Interactions; Insecticides; Monocrotophos; Organothiophosphorus Compounds; Pyrethrins; Soil; Soil Microbiology; Soil Pollutants; Time Factors; Up-Regulation

Three insecticides, monocrotophos, quinalphos, and cypermethrin, were applied at 0, 5, 10, and 25 microg g(-1) either singly or in combination to a black clay soil to investigate their effects on the soil microflora and dehydrogenase activity. All three insecticides significantly enhanced the proliferation of bacteria and fungi and the soil dehydrogenase activity even at the highest level of 25 microg g(-1). Monocrotophos or quinalphos in combination with cypermethrin at tested levels interacted significantly to yield additive, synergistic, and antagonistic responses toward bacteria and fungi and dehydrogenase activity in soil. Antagonistic interactions were more pronounced toward soil microflora and dehydrogenase activity when the two (monocrotophos or quinalphos + cypermethrin) insecticides were present together in the soil at highest level (25 + 25 microg g(-1)), whereas synergistic or additive responses occurred at lower level with the same combination of insecticides in soil.

Topics: Bacteria; Drug Interactions; Fungi; Insecticides; Monocrotophos; Organothiophosphorus Compounds; Oxidoreductases; Pyrethrins; Soil Microbiology; Stem Cells

Moth larvae (Helicoverpa armigera Hübner) collected from field crops were tested for resistance to cypermethrin, fenvalerate, endosulfan, monocrotophos and quinolphos. Larvae were treated with a dose of the pesticide that would kill 99% of the susceptible insects. The percent survival of the resistant strains was determined. Highest seasonal average percentage survival was recorded by fenvalerate (65.0%) followed by cypermethrin (62.4%). Acetylcholinesterase of resistant larvae was less sensitive to monocrotophos and methyl paraoxon. Resistant larvae showed higher activities of esterases, phosphatases and methyl paraoxon hydrolase compared with susceptible larvae. The presence of high activity of esterases was attributed to appearance of extra bands of esterases in native PAGE. The presence of P-glycoprotein expression was detected in resistant larvae using P-gp antibodies; this was not detected in the susceptible larvae. Our results indicate that the high level of resistance detected in the field pests could be because of a combined effect of decreased sensitivity to AChE, higher levels of esterases, phosphatases and the expression of P-gp.

Topics: Animals; Antibodies; ATP Binding Cassette Transporter, Subfamily B, Member 1; Biological Assay; Electrophoresis, Polyacrylamide Gel; Endosulfan; Esterases; Hydrolases; Insecticide Resistance; Insecticides; Larva; Monocrotophos; Moths; Nitriles; Organothiophosphorus Compounds; Paraoxon; Phosphoric Monoester Hydrolases; Pyrethrins; Seasons

Monitoring for organophosphate and carbamate resistance was carried out on five major insect pests of cotton collected from 22 cotton-growing districts across India. Resistance was monitored in Helicoverpa armigera (Hübner) and Pectinophora gossypiella (Saunders) for the period 1995-1999 and for Spodoptera litura (Fabricius), Earias vittella (Fabricius) and Bemisia tabaci (Gennadius) in a survey conducted during the 1997-98 cropping season. Of the 53 field strains of H. armigera, only four were found to exhibit resistance to quinalphos, the highest 15-fold, whereas all 16 field strains tested were found to be resistant to monocrotophos. Similarly, out of 40 field strains tested, only eight were found to express appreciable resistance to methomyl. Resistance in P. gossypiella to quinalphos was high in the majority of the strains tested. Of the seven strains of E. vittella tested, two strains from northern India exhibited > 70-fold resistance to monocrotophos. Of the 11 S. litura strains tested, only four were found to exhibit resistance factors of 10 to 30-fold to quinalphos and monocrotophos. All of the B. tabaci field strains exhibited resistance to methomyl and monocrotophos and susceptibility to triazophos. Practical implications for pest control resulting from the observed patterns of cross-resistance between quinalphos, monocrotophos and methomyl are discussed.

Topics: Animals; Gossypium; Hemiptera; India; Insect Control; Insecticide Resistance; Insecticides; Methomyl; Monocrotophos; Moths; Organothiophosphorus Compounds; Spodoptera

Topics: 2,4-Dichlorophenoxyacetic Acid; Benzimidazoles; Biodegradation, Environmental; Biomass; Captan; Carbamates; Monocrotophos; Nitrogenase; Organothiophosphorus Compounds; Pest Control; Pesticide Residues; Pesticides; Rhodobacter; Rhodopseudomonas; Soil Microbiology; Structure-Activity Relationship

The interaction of insecticide combinations of monocrotophos and quinalphos on Anabaena torulosa, by the criteria of absorbance (OD) and packed cell volume (PCV) of the culture, content of chlorophyll a, phycocyanin, carotenoids, total protein, DNA and RNA, heterocyst differentiation and nitrogen fixation, were assessed. In general, monocrotophos and quinalphos, in combination, interacted significantly yielding three different responses viz., additive, antagonistic or synergistic. The nature of the interaction found with OD and PCV was nearly the same for a particular concentration of the insecticides. However, no consistent interaction was observed with respect to carotenoids and phycocyanin. The three types of interaction were noticed for total protein, DNA and RNA. Interestingly, the insecticide combinations at lower concentrations yielded all interaction responses for heterocyst frequency and nitrogenase activity. But, higher concentrations, in combination, resulted in synergism for heterocyst differentiation and nitrogen fixation.

Topics: Anabaena; Bacterial Proteins; Carotenoids; Chlorophyll; Chlorophyll A; Culture Media; DNA, Bacterial; Drug Interactions; Drug Synergism; Insecticides; Monocrotophos; Nitrogen Fixation; Organothiophosphorus Compounds; Phycocyanin; RNA, Bacterial; Soil Microbiology; Spectrophotometry, Ultraviolet

Topics: Azospirillum; Bacillus; Biodegradation, Environmental; Insecticides; Monocrotophos; Nitriles; Organothiophosphorus Compounds; Pesticide Residues; Pyrethrins; Soil Microbiology

The application (up to 5 kg ha-1) of monocrotophos or quinalphos to four types of agricultural soils significantly stimulated the mineralization of peptone-nitrogen and the oxidation of ammonium-nitrogen. In soils treated with 2.5 kg ha-1 of either insecticide, the rate of ammonification and nitrification was fairly rapid after 2 and 4 weeks of incubation. The enhancement of both transformations, mediated by microorganisms, was significantly more in the quinalphostreated soils. The results suggest that a balance between the effect of insecticides on insect pests and their impact on beneficial microbial activities in soil must be determined.

Topics: Ammonia; Insecticides; Monocrotophos; Nitrates; Organothiophosphorus Compounds; Soil

The status of cell-mediated immunity (CMI) after pesticide exposure was assessed in mice with the help of skin sensitivity and graft versus host reaction tests. It was observed that at 24 hours post-challenge CMI values did not differ significantly from the control, indicating no effect of quinalphos treatment in mice. Goats receiving monocrotophos at a dose rate of 1.0 mg kg-1 body mass for 40 days gave a similar result when CMI was tested with the help of the chemical sensitizer dinitrofluorobenzene (DNFB). Thus the results clearly indicate that the tested organophosphates do not interfere with cellular immunity in the intoxicated animals.

Topics: Animals; Chickens; Goats; Graft vs Host Reaction; Immunity, Cellular; Insecticides; Male; Mice; Monocrotophos; Organothiophosphorus Compounds; Poisoning

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 population 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 subculturings of the isolates from insecticide-treated soils had no effect on their nitrogen-fixing activity.

Topics: Bacteria; Insecticides; Monocrotophos; Nitrogen Fixation; Organothiophosphorus Compounds; Soil Microbiology; Soil Pollutants

Topics: Eukaryota; Insecticides; Monocrotophos; Organothiophosphorus Compounds; Soil; Species Specificity