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Aim: The present study aims to establish morphology-based nuclear abnormalities (NAs) including micronuclei (MN) as effective and sensitive genotoxic endpoint biomarkers in fish against the sub-lethal exposure of phorate. Methodology: Fish, Channa punctatus (35 ± 3.0 g; 14.5 ± 1.0 cm) were randomly exposed in two sets, treated group 1 and 2 (0.0375 mg l-1 and 0.075 mg l-1 of phorate, respectively) along with a simultaneous control (0 mg l-1). The blood was sampled after 30 days. Results: A significant (p < 0.05) induction in reactive oxygen species (ROS) coupled with elevated frequency of blood cells showing micronuclei along with the gross appearance of notched nuclei, curved nuclei, blebbed nuclei, kidney-shaped nuclei, V-shaped nuclei, nuclear buds, nucleoplasmic bridges, dumbbell nuclei, and condensed/rounded nuclei were recorded in a dose-dependent manner. Interpretation: A significant (p < 0.05) induction in reactive oxygen species (ROS) coupled with elevated frequency of blood cells showing micronuclei along with the gross appearance of notched nuclei, curved nuclei, blebbed nuclei, kidney-shaped nuclei, V-shaped nuclei, nuclear buds, nucleoplasmic bridges, dumbbell nuclei, and condensed/rounded nuclei were recorded in a dose-dependent manner.

Phorate is a systemic insecticide used to eradicate mites, insects, and nematodes. Extensive use of this organophosphate has engendered severe environmental concerns. The current research aimed to explore the kinetic pathways of phorate biodegradation in aqueous solutions. Two novel bacterial strains Pseudomonas aeruginosa strain PR1 (KP268772.1) and Pseudomonas sp. PR_02 (KP268773.1) were isolated, screened, and developed given their potential to degrade phorate. Mineralization of phorate was assayed with and without the addition of metal ions [Fe (II) and Cu (II)] and humic acid (HA). In 14 days, experiment both strains have consumed about 69%-94.5% (half-life from 3.58 to 6.02 days) of phorate. The observed biodegradation rate of phorate with Cu (II) in the system was 73% and 87%, with a half-life of 4.86 and 4.07 days for PR1 and PR2, respectively. The biodegradation of phorate using Fe(II) was 69% and 82%, with half-life periods 5.68 and 4.49 days. Meanwhile, incorporating HA, the phorate biodegradation was inhibited significantly, showing 71% and 85% degradation, with half-life periods of 6.02 and 5.02 days. The results indicated that both bacterial strains were able to mineralize phorate with PR2 > PR1. Summarizing, the inhibition in phorate biodegradation order under different conditions was as HA > Fe (II) > Cu (II). UV-visible measurements and gas chromatography-mass spectrometric assays indicated that the possible degradation pathway of phorate included ethoxy-phosphonothio-methanethiol S-mercaptomethyl-O,O-dihydrogen phosphorodithioate, diethyl-methylphosphonate, methane dithiol, ethanethiol, and phosphate, as the main metabolites identified. Therefore, it was concluded that the newly isolated Pseudomonas strains could be a potential candidates for biodegradation of phorate in a cost-effective, safe, and environmentally friendly alternative.

It is highly advantageous to devise an in vitro platform that can predict the complexity of an in vivo system. The first step of this process is the identification of a xenobiotic whose monooxygenation is carried out by two sequential enzymatic reactions. Pesticides are a good model for this type of tandem reactions since in specific cases they are initially metabolised by human flavin-containing monooxygenase 1 (hFMO1), followed by cytochrome P450 (CYP). To assess the feasibility of such an in vitro platform, hFMO1 is immobilised on glassy carbon electrodes modified with graphene oxide (GO) and cationic surfactant didecyldimethylammonium bromide (DDAB). UV-vis, contact angle and AFM measurements support the effective decoration of the GO sheets by DDAB which appear as 3 nm thick structures. hFMO1 activity on the bioelectrode versus three pesticides; fenthion, methiocarb and phorate, lead to the expected sulfoxide products with K

BackgroundTea is an important plantation crop in India and world. Introduction of fertilisers and pesticides for better production polluted tea garden soils. Phosphates in agricultural soils are converted into soluble forms by phosphate solubilising microorganisms (PSMs). Consortium of PSM having high tolerance level is an attractive option for bioremediation of degraded tea plantation soils. This research initiative was to isolate PSM from tea plantation soil and detect their tolerance against pesticide, antibiotic and antifungal.ResultsIsolated consortia from organic and inorganic tea plantation soils of Darjeeling showing halo was considered for tolerance study. Phorate was most and Deltamethrin was the least tolerant pesticide for the isolated PSM consortia. So, Phorate may be considered as most used or most accumulated pesticide. Erythromycin was most and Ofloxacin was the least tolerant antibiotic while Fluconazole was most and Itraconazole was the least tolerant antifungal agent for the isolated PSM consortia. It was noted that there was no or partial inhibition of PSM growth by some pesticide, antibiotic and antifungal agents. In all the three tolerance studies it was observed that there is no relation between collection sites but in all the assays average inhibition zones were more in organic plantations than inorganic plantations.ConclusionsThus, it may be said that inorganic practice induces tolerance to microbes. So, other than cultural practice use of chemicals, micro-ecosystem and antibiosis exhibited by microbes do play a role in conferring tolerance.

Cucumber (Cucumis sativus L.) is a high nutritious and mineral-rich vegetable, which occupies a prominent place as a salad and vegeta-ble. It is being used in many ways in the daily diet of humans and widely cultivated worldwide. The decrease of agricultural land, ad-verse environmental conditions and continuous increase of popula-tion, the demand of nutritious food is a matter of great concern to the world. Protected cultivation is a very effective tool to solve this problem because in this cultivation the productivity of crops is very high as compared to open field conditions. High value crops suc-cessfully grown in protected cultivation, specially vegetables (cu-cumber, tomato, Capsicum etc.) which are highly susceptible to the numerous pests and pathogens, including phyto-parasitic nema-todes (specially root-knot nematode, Meloidogyne spp.). With this view, present trial was taken to estimate the avoidable losses caused by Meloidogyne incognita infecting cucumber in poly-house situated on farmer’s field with the application of phorate at 2 kg a.i. ha-1 over check. Results exhibited that application of chemical treatment significantly reduced number of galls per 5 g roots, egg masses per 5 g roots, eggs & juveniles per egg mass and final nema-tode population 79.03, 81.10, 30.91 and 56.54%, respectively. Avoidable yield losses were recorded to the tune of 66.84% on cu-cumber by M. incognita in poly-house.

Three resistant (R) rigid ryegrass (Lolium rigidum Gaudin) populations from southern Australia (EP162, 375-14, and 198-15) with cross-resistance to thiocarbamate, chloroacetamide, and sulfonylisoxazoline herbicides displayed reduced sensitivity to the isoxazolidinone herbicides bixlozone and clomazone. Each of these R populations was exposed to two cycles of recurrent selection (RS) in which plants were treated with the field rate of bixlozone, survivors were bulk crossed, and seed was collected. After the first cycle of recurrent selection (RS1), the LD50 to bixlozone in population 198-15 increased to 17.5-fold compared with the S population and increased further to 26.9-fold after a second cycle of recurrent selection (RS2). The recurrent selection process also increased the level of resistance to bixlozone in populations EP162 and 375-14 (7.8- to 18.4-fold) compared with the S population. Phorate antagonized bixlozone and clomazone in SLR4 (34.6- and 28.1-fold increase in LD50) and both herbicides in populations EP162 (36.5- to 46.6-fold), 375-14 (71.4- to 73.9-fold), and 198-15 (86.4- to 91.5-fold) compared with the absence of phorate. The increase in LD50 of all L. rigidum RS populations when treated with phorate suggests a lack of herbicide activation is not the likely resistance mechanism to these herbicides. This research highlights the elevated risk of thiocarbamate-resistant L. rigidum populations to rapidly evolve resistance to the isoxazolidinone herbicides bixlozone and clomazone.

Understanding the interactions between nanoparticles and organophosphates is the key to developing cost-effective colorimetric pesticide detection. We have studied the interaction between three different organophosphates containing the PS group and borohydride stabilized silver nanoparticles. Three different organophosphates, namely phorate, chlorpyrifos, and malathion, have been used. The colorimetric changes are corroborated with UV-visible absorption studies along with the change in particle size and zeta potential. This effect persists in the presence of NaCl solution also. The chlorpyrifos and malathion do not show significant interactions with uncapped nanoparticles over time, while phorate undergoes degradation due to the scission of the S–CH2 linkage. A reaction mechanism, wherein a silver and sulfur (Ag→S) complex is formed, which is in agreement with Raman spectroscopic studies is proposed. The orientations of phorate near Ag nanoparticles are discussed from the adsorption energy calculation using density functional theory.

White grubs are one of the major pests of sugarcane crop in coastal Andhra Pradesh, India. The present study was taken up to assess the efficacy of biocontrol agents viz., entomopathogenic fungi and entomopathogenic nematodes for management of white grub, Holotrichia consanguinea in sugarcane ecosystem during 2015-16 and 2016-17. Two entomopathogenic fungi, Metarhizium anisopliae (NBAIR Ma4 strain) and Beauveria bassiana (NBAIR Bb5a), two entomopathogenic nematodes ( Heterorhabditis indica NBAIR-H38 and Steinernema carpocapsae NBAII Sc 05), Neem cake, Phorate 10G were evaluated through soil application as different treatments in white grub infested sugarcane field in coastal Andhra Pradesh for two seasons during 2015 and 2016-17. All biocontrol agent treatments were better than the insecticidal/neem cake application in the management of sugarcane white grubs.However, based on cost benefit ratio of the treatments, soil application of M. anisopliae @ 2.5 kg along with 250 kg farm yard manure per hectare (twice application in July and August) proved superior to other biocontrol agent treatments. Soil application of biocontrol agents, Phorate and Neem cake did not show anydeleterious effect on non-target organisms like, earthworms, earwigs, spiders, coccinellids and chrysopids.

Transmission Electron Microscopic (TEM) assessments were performed on the renal cells of common carp Cyprinus carpio to observe the deleterious effects of two organophosphate insecticides, Phorate and Dimethoate. Pesticides such as Phorate and Dimethoate often pollute aquatic systems where they may negatively impact fish, but so far, the ultrastructural toxicity of these pesticides remains poorly understood. Here, we use Transmission Electron Microscopy (TEM) to determine how acute exposure to sublethal concentrations of these two pesticides may affect the renal cells of common carp Cyprinus carpio. For each insecticide, the fish were divided in four experimental conditions: a control and three different exposure concentrations of the pesticide. The Phorate treated fish were exposed to three sublethal concentrations of 0.2 mg/L, 0.4 mg/L, 0.6 mg/L for a duration of 24, 48 & 72 h. The dimethoate treated fish were exposed to three sublethal concentrations of 0.005 mL/L, 0.01 mL/L, 0.015 mL/L for a duration of 24, 48 and 72 h. The two-dimensional transmission electron microscopy revealed ultrastructural abnormalities in the treated fish renal cells when exposed to two toxicants including deformation in the glomerulus, vacuolization of cytoplasm, degenerative nucleus and damaged mitochondria. Furthermore, the ultrastructural abnormalities were more prominent with the increase in the concentrations of both the insecticides and also with their exposure period. Overall, these results provide important baseline data on the ultrastructural toxicity of Phorate and Dimethoate and will allow important follow-up studies to further elucidate the underlying cellular mechanisms of pesticide toxicity in wildlife.

Native rhizobacteria were isolated from agriculture soil and evaluated for their pesticide remediation potential. Native rhizobacterial isolates (RBI1, RBI2, RBI3 and RBI4) employed in the study exhibited high levels of tolerance towards phorate (10% CG) registering MIC (minimum inhibitory concentration) values, between 1450-2010 ppm. The isolates RBI1, RBI4 exhibited effeciency (35%-87%) to catabolise/co-metabolise phorate as sole energy (C\P) source at concentration as high as 500 ppm. FTIR analysis suggested evidence for degradtion of complex parent compound (phorate) to less complex degradtion metabolites. Disappearance of specific ester linkages in control (1025.43, 998.37 and 908.99cm-1) suggested hydrolysis of ester bonds, which is a sure indication of organophosphate‘s degrdation. Phorate degradation by native isolate was further quantified through HPLC analysis presenting 42% degradation (within 48hrs) at concentrations 10-15 fold higher (300 ppm) as compared to residual phorate reported in soils. Current study is the very first report providing a biologically safe option of rhizoremediation to degrade higher concentrations of persistent phorate residues, at concentrations rarely explored thus far. Thus the study provides substantial evidence regarding the potential of rhizobacterial isolates to be developed as bioinoculants and applied for accelerated remediation of toxic phorate residues.

The proposed method is based on flotation–dissolution an easy, impressible, extractive spectrophotometric determination, explained for easy investigation of the organophosphate pesticide phorate (O,O-diethyl S-[ethylthiomethyl] phosphorodithioate) on trace levels. A molybdophospho complex is generated when prorate is treated with ammonium molybdate in acidic medium. As an ion associate complex with methylene blue the complex is present in between of the water and organic layers which is extracted and then dissolved with acetone. The greenish blue complex produced show absorption maxima at 660 nm. Beer’s law range is found to be 0.5 to 16 µg per 10 ml for phorate. The molar absorptivity is 0.989×103 L mol-1 cm-1 and sandell’s sensitivity is 1.00×10-5 µg cm-2. Also calculated the standard deviation and relative standard deviation for the above method were ±0.006 and 1.95% respectively. The method has been applied and checked for the determination of phorate in water, soil and vegetables.

The main objective of this study was to assess the pesticide removal efficiency of chitosan in grape juice during clarification. The grape juice was spiked with six selected pesticides (chlorpyrifos, ethion, diazinon, fenitrothion, fenthion and phorate) and clarified with chitosan at different concentrations and at three different incubation times (1, 2 and 4 h). The effect of chitosan on the level of pesticides in grape juice during clarification was quantified using modified QuEChERS method with gas chromatography with tandem mass spectrometry (GC-MS/MS). The method for pesticide quantification has been validated. The maximum removal was obtained for chlorpyrifos (98%) and ethion (97%) at 0.5% of chitosan concentration for 1 h incubation followed by phorate (96%), fenthion (95%), fenitrothion (94%) and diazinon (86%) at 1% of chitosan concentration for 2 h incubation time. The juice was clarified with other clarifying agents such as activated carbon, gelatin, casein and bentonite and its pesticide removal efficiency was compared with chitosan. The pesticide removal level could be correlated with the properties of selected pesticides and clarifying agents. The results indicated that the chitosan can act as an effective pesticide scavenger and it leads to the potential application of chitosan in fruit juice clarification.

This study investigates the potential of native biocontrol agents (BCAs) as controls against Ganoderma lucidum causing root rot mortality in Indian mesquite. The disease is prevalent in sandy soils where trees grow under rainfed conditions. In addition, a beetle namely Acanthophorus serraticornis damages the roots, resulting in increasing vulnerability of the host thereby allowing easy of the pathogen. In dual culture tests, Ganoderma infected cowpea root bit experiment and compatibility with insecticides revealed that the three BCAs (Trichoderma longibrachiatum, T. harzianum, and Aspergillus nidulans) significantly inhibited G. lucidum mycelial growth. The highest mycelial growth inhibition (47.6%) was recorded after 96 h followed by 39.8% and 29.3% at 72 and 48 h, respectively, by T. longibrachium. Cell free filtrates of T. longibrachiatum, T. harzianum, and A. nidulans were superior in inhibiting mycelium growth. A low concentration (3 ml) of T. longibrachiatum was more effective in inhibiting mycelium growth compared to other BCAs. Both Prosopis juliflora compost and onion residue compost amendments as food substrates favored the growth of these BCAs, which ultimately reduced the viability of Ganoderma-colonized root bits of cowpea. Studies on compatibility between insecticides and BCAs suggests that T. longibrachiatum, harzianum and A. nidulans can be combined with phorate or chloropyriphos (both organophosphates) at variable concentrations if amended together for partially infected trees, or as a prophylactic measure in healthy trees. These studies demonstrate that there is considerable opportunity for using native BCAs against G. lucidum in managing root rot disease.

Background: Individuals have the chance to get exposed to organophosphates either at domestic, or industrial spheres. Organophosphate poisoning is a worldwide problem. Organophosphate insecticides inhibit Cholinesterase enzymatic activity. Chlorpyrifos, Phorate 10% granules and Monocrotophos are insecticides and pesticides commonly used in India by farmers. Aim: The present study aims at determining the effect oforganophosphate compounds on thyroid profile in individuals exposed to acute poisoning. Materials and Methods: In this study, those individuals who were acutely presented at the emergency department, SVS Medical College, Mahabubnagar, with a history of intentional or accidental intake of either chlorpyrifos or Phorate 10% granules or Monocrotophos (Organophosphorus compounds) were taken as cases. Intake of these compounds was confirmed by analyzing serum cholinesterase levels. Those patients having a serum cholinesterase levels value below 4000 U/L were included in this study. Simultaneously, the sample was analyzed for thyroid profile that includes Total triiodothyronine (TT3), Total tetraiodothyronine (TT4) and Thyroid stimulating hormone (TSH). Reanalyzing of thyroid profile was done after a time gap of one month from the day of discharge from hospital after recovery. Results: Total T3, Total T4 and TSH values showed statistically significant change (p-value between the acute poisoning phase and one month follow up phase of after recovery. Conclusion: Total T4 values are significantly higher in acute organophosphorus poisoned phase mimicking thyrotoxicosis, and return to normal biological reference range after recovery, whereas TSH values in acute opiates poisoned phase were significant lower than that of recovery phase. Keywords: Organophosphorus compounds (OPC), Total triiodothyronine(TT3), Total tetraiodothyronine(TT4), Thyroid stimulating hormone (TSH), Cholinesterase enzyme.

A sensitive and selective assay based on liquid chromatography–tandem mass spectrometric method was developed for quantification of phorate in river water. The chromatographic separation of phorate was achieved on Zorbax C18 column using two mobile phase consisting 0.1% formic acid in methanol, and 0.1% formic acid in MilliQ water (v/v ratio of 96:04) by isocratic elution method at a flow rate of 300 µL/min. The quantification was carried out using multiple reaction monitoring transitions of m/z 261/75 for phorate. The lower limit of detection and limit of quantification for the developed UPLC-MS/MS was 0.08 ng/mL and of 0.19 ng/mL respectively. The assay was validated for selectivity, linearity, accuracy and precision. The developed assay was then employed for quantification of phorate in river water and wetland treated water. The role of constructed wetlands (CW) in phorate removal was established in this study. The removal efficiency of phorate by Constructed Wetland was found to be 60–90% along with an overall 70–90% reduction in chemical oxygen demand (COD), biological oxygen demand (BOD) and phosphorus (P).

Organophosphate insecticides, which have the capacity to inhibit specific herbicide-degrading (cytochrome P450) enzymes, have been used to explore metabolic herbicide-resistance mechanisms in weeds. This study investigates the response of seven field-selected rigid ryegrass (Lolium rigidum Gaudin) populations to herbicides from three different sites of action in the presence or absence of the P450 inhibitor phorate. Phorate antagonized the thiocarbamate herbicides triallate and prosulfocarb (8-fold increase in LD50) in multiple resistant L. rigidum populations with resistance to three different site-of-action herbicides. In contrast, phorate synergized trifluralin and propyzamide in some populations, reducing the LD50 by 50%. Conversely, treatment with phorate had no significant effect on the LD50 for S-metolachlor or pyroxasulfone (inhibitors of very-long-chain fatty-acid synthesis). Phorate has diverse effects that are herbicide and population dependant in field-selected L. rigidum, suggesting P450 involvement in the metabolism of trifluralin and failure to activate thiocarbamate herbicides in these populations. This research highlights the need for implementation of diverse approaches other than herbicide alone as part of a long-term integrated strategy to reduce the likelihood of metabolism-based resistance to PPI herbicides in L. rigidum.

Tomato spotted wilt (TSW) is a common and serious disease of peanut (Arachis hypogaea L.) caused by Tomato spotted wilt virus (TSWV; family Tospoviridae, genus Orthotospovirus). Management frequently uses an integrated approach, with cultivar resistance and application of in-furrow insecticide as two critical components. In-furrow insecticides help suppress thrips, which can injure and stunt young growing plants and transmit TSWV, with postemergent application of acephate capable of providing additional thrips control. To examine effects of systemic insecticides (imidacloprid, imidacloprid plus fluopyram, phorate, and acephate) on TSW management, yield, and economic return across cultivar susceptibilities (susceptible, moderately susceptible, and resistant) in South Carolina, a meta-analysis was used to synthesize results from 32 studies conducted between 2009 and 2018. Although efficacy and magnitude of individual treatments varied with susceptibility, imidacloprid increased, whereas phorate generally decreased TSW incidence relative to nontreated controls. In-furrow treatments followed by acephate further reduced TSW incidence and increased profitability. All examined treatments improved yield compared with untreated peanuts except for susceptible cultivars treated with imidacloprid. Imidacloprid plus fluopyram increased yield more than imidacloprid alone for the susceptible group, although there was little difference between these treatments in association with moderately susceptible cultivars. When comparing individual applications, phorate was overall the most profitable option across susceptibilities, although imidacloprid plus fluopyram exhibited analogous profitability for susceptible cultivars. Results from this study can be used to assist producer selection of management options for TSW in peanut.

A statistically designed field experiment with ten treatments including an untreated control replicated thrice in Randomized Block Design was conducted in root- knot nematode infested fig (cv. Poona fig) orchard. All the treatments were significantly superior over an untreated control in reducing root- knot nematode population, number of root galls and egg masses and increasing the yield of fig. However, soil application of carbofuran 3G at 2 kg a.i./ha was found to be most effective in reducing root-knot nematode population (53.66%), number of root galls (50.19%) and number of egg masses (45.36%) at intermediate stage and increasing the fruit yield of fig (37.85%) with 1:17.79 ICBR at termination. This treatment was followed by the treatment of phorate 10 G at 2kg a.i./ ha. The reduction in root- knot nematode population, number of root galls and egg masses and increase in fruit yield recorded in this treatment were 49.46, 50.11, 42.31 and 28.19%, respectively with 1: 33.64 ICBR. While, at termination stage, the treatment of Phule Trichoderma plus at 20 kg/ha was found to be most effective in reducing nematode population (40.36%), number of root galls (37.08%) and number of egg masses (41.02%) and increasing the fruit yield of fig (13.54%) with 1: 11.20 ICBR. This was followed by the treatments with rest of the biocontrol agents. The reduction in root- knot nematode population, number of root galls and number of egg masses and increase in fruit yield of fig recorded in these treatments ranged from 32.03 to 38.50, 29.31 to 36.00, 31.90 to 35.97 and 11.54 to 20.75%, respectively with 1: 9.80 to 1: 20.04 ICBR.

For the visual detection of four organophosphorus pesticides (OPs), a colorimetric aptasensor was developed based on aptamer-mediated bimetallic metal-organic frameworks (MOFs) nano-polymers. Fe-Co magnetic nanoparticles (MNPs) and Fe-N-C nanozymes were prepared based on pyrolytic reaction, and were labeled with broad spectrum aptamers and complementary chains of organophosphorus pesticides respectively. The hybridization of aptamers and complementary chains led to the formation of nano-polymers. In the presence of target pesticides, they competed with complementary chains for aptamers on Fe-Co MNPs, resulting in a large number of Fe-N-C nanozymes signal labels being released into the supernatant. Fe-N-C nanozymes showed similar activity to peroxidase and catalyzed the 3,3',5,5'-tetramethylbenzidine-hydrogen peroxide (TMB-H

It has been estimated that approximately one in seven of all global suicides is due to pesticide self-poisoning, mostly in rural areas of developing countries. Organophosphorus (OP) compounds are a group of pesticides exerting their toxicological effects through non-reversible inhibition of the enzyme acetylcholinesterase (AChE). Among these compounds, phorate (thimet) is one of the most dangerous compounds, the use of which is restricted in many countries. A case of intentional suicide after phorate ingestion in a 24-year-old Bengali male is described. This is the second case of suicidal ingestion of phorate reported in the forensic literature, and the first presenting complete toxicological findings.

Spotted wilt of peanut (SWP) (Arachis hypogaea L.) caused by Tomato spotted wilt virus (TSWV; family Tospoviridae, genus Orthotospovirus) is a common disease that causes severe economic losses in peanut producing regions of the world. The causal agent is transmitted by thrips (Thysanoptera: Thripidae). Field experiments were conducted in 2017 and 2018 to determine if management of spotted wilt and subsequent productivity of peanut, including economic value, could benefit from applying a superabsorbent polymer (SAP) with standard in-furrow insecticides at planting. To determine this, two individual experiments were performed. In the first study, phorate and imidacloprid were individually applied with (2.24 kg/ha) or without SAP across cultivars susceptible (FloRun 157 or TUFRunner 511), moderately susceptible (Georgia 06G), and resistant (Sullivan or TifNV-High O/L) to TSWV. Nontreated controls were included in all experiments. The second study sought to determine the efficacy of different rates of SAP (0, 2.24, 5.6, and 8.97 kg/ha). The initial study was conducted in three locations across South Carolina and Georgia, while the second was conducted at Blackville, SC. In the first study, incidence of SWP was reduced (P = 0.0547) in multiple location-year analysis with a reduction of 9.4% observed in susceptible cultivars treated with phorate compared to untreated checks and those with imidacloprid. SAP did not affect final SWP incidence or economic value (P > 0.05) and was not consistently significant for yield. From the SAP rate study, a linear relationship of decreasing SWP incidence was observed with increasing SAP application rates for both imidacloprid and phorate in 2017 and 2018. On a means comparison basis, SWP was lower than the no-SAP check at SAP rates of 5.56 and 8.97 kg/ha, but this did not necessarily translate into increased yield. Additional experiments are needed to elucidate the relationship superabsorbent polymer may have to susceptible cultivars and phorate.

Tobacco thrips (Frankliniella fusca Hinds) is an important pest in peanut (Arachis hypogaea L.) in North Carolina and injury from this insect can lower yield. Research was conducted from 2012 through 2014 in North Carolina to compare visible injury from tobacco thrips feeding and peanut yield when acephate, imidacloprid, and phorate were applied alone in the seed furrow at planting or followed by acephate applied postemergence 3 weeks after planting. In a second experiment conducted during the same time period, a commercial liquid formulation of Bradyrhizobia inoculant was applied alone or with imidacloprid in fields with and without plantings of peanut in recent years. Peanut injury from tobacco thrips feeding was reduced by acephate, imidacloprid, and phorate applied in the seed furrow at planting compared with non-treated peanut. Acephate applied 3 weeks after planting generally reduced injury from thrips. Pod yield was greater when imidacloprid was applied compared with yield for the non-treated control or when acephate was applied in the seed furrow. Pod yield was similar regardless of in-furrow treatment when acephate was applied postemergence. Thrips control by imidacloprid was not affected by Bradyrhizobia inoculant, and imidacloprid did not negatively affect efficacy of Bradyrhizobia inoculant regardless of previous field history. These data indicate that imidacloprid protects peanut as well as or more effectively than the systemic insecticides acephate and phorate and that imidacloprid is compatible with Bradyrhizobia inoculant.

Establishing an adequate stand of peanut (Arachis hypogaea L.) and minimizing the negative impact of tobacco thrips [Frankliniella fusca (Hinds)] is important for maximizing yield in both organic and conventional production systems. The incidence, severity, and impact of soil borne pathogens and thrips populations on peanut may be influenced by planting date, fungicide seed treatment, and/or systemic insecticide application. However, the interaction of these management techniques has not been investigated in North Carolina with Virginia market type cultivars to date. As such, research was conducted over four years in North Carolina to determine peanut stand, injury caused by tobacco thrips feeding, and pod yield as influenced by planting date (early, mid-, and late-May), fungicide seed treatment, and phorate applied in the seed furrow at planting. Peanut stand increased when planting fungicide-treated seed compared to non-treated seed, although the magnitude of this effect lessened with later May plantings. Regardless of phorate treatment, less thrips injury was noted when peanut was planted in mid- or late-May compared with early May in three of four years. Yet the addition of phorate in-furrow further reduced thrips injury at every planting date. Peanut yield increased 75% and 50% of the time when seed was treated with fungicide and phorate was applied in the seed furrow at planting, respectively. Yield was generally greater when peanut was planted in mid-May and late-May compared to planting in early May irrespective of fungicide seed treatment or phorate treatment. Peanut stand was negatively and positively correlated with observed thrips injury and peanut yield, respectively. Additionally, peanut yield was negatively correlated to thrips injury. These data suggest that conventional producers should utilize treated seed and phorate in-furrow for thrips management regardless of planting date and that organic producers should plant in late May to minimize negative impacts of thrips and soil borne pathogens.

Human exposure to pesticides can be estimated through different approaches. The approach adopted in this study is based on internal dose measures. Studies published during 2001 and 2017 were collected from PubMed and Scopus databases, filtered and organized. The intake of parent compounds is estimated based on the urinary excretion of different OP metabolites applying a mathematical model previously used for similar purposes. Once defined an Estimated Daily Intake (EDI), risk assessment is performed through comparison with specific guideline values and hazard index (HI) is calculated to assess cumulative health risk. The EDI was expressed as malathion, diazinon, parathion, phorate and dimethoate equivalents. Differences in exposure between pregnant women, general population, children and farmers are highlighted and exposures are presented by country and sampling year. Higher exposure to OPs was calculated for farmers, followed by children whereas pregnant women were less exposed. Median HQ values for children ranged between 0.016 and 0.618, for pregnant women 0.005-0.151, for general population 0.008-0.206 and for farmers 0.009-0.979. Combined exposure to dimethoate and phorate was the worst-case scenario. The annual distribution of the urinary DAPs showed that exposure to OPs since 1998 tends to be stable for both children and adults.

Organophosphorus pesticides (OPS) are widely used in the world, and many poisoning cases were caused by them. Phorate intoxication is especially common in China. However, there are currently few methods for discriminating phorate poisoning death from phorate exposure after death and interpretation of false-positive results due to the lack of effective biomarkers. In this study, we investigated the metabonomics of rat plasma at different dose levels of acute phorate intoxication using ultra-performance liquid chromatography quadrupole-time of flight mass spectrometry (UPLC-Q-TOF-MS) analysis. A total of 11 endogenous metabolites were significantly changed in the groups exposed to phorate at LD50 level and three times of LD50 (3LD50) level compared with the control group, which could be potential biomarkers of acute phorate intoxication. Plasma metabonomics analysis showed that diethylthiophosphate (DETP) could be a useful biomarker of acute phorate intoxication. The levels of uric acid, acylcarnitine, succinate, gluconic acid, and phosphatidylcholine (PC) (36:2) were increased, while pyruvate level was decreased in all groups exposed to phorate. The levels of ceramides (Cer) (d 18:0/16:0), palmitic acid, and lysophosphatidylcholine (lysoPC) (18:1) were only changed after 3LD50 dosage. The results of this study indicate that the dose-dependent relationship exists between metabolomic profile change and toxicities associated with apoptosis, fatty acid metabolism disorder, energy metabolism disorder especially tricarboxylic acid (TCA) cycle, as well as liver, kidney, and nervous system functions after acute exposure of phorate. This study shows that metabonomics is a useful tool in identifying biomarkers for the forensic toxicology study of phorate poisoning.

Organophosphorus pesticides (OP

Late and early leaf spot are caused by Nothopassalora personata and Passalora arachidicola, respectively, and are damaging diseases of peanut (Arachis hypogaea L.) capable of defoliation and yield loss. Management of these diseases is most effective through the integration of tactics that reduce starting inoculum and prevent infection. The insecticide phorate was first registered in 1959 and has been used in peanut production for decades in-furrow at planting to suppress thrips. Phorate further provides significant suppression of Tomato spotted wilt virus infection beyond suppression of its thrips vector alone by activating defense-related responses in the peanut plant. From six experiments conducted from 2017 to 2019 in Blackville, SC, Reddick, FL, and Quincy, FL, significantly less leaf spot defoliation was exhibited on peanuts treated with phorate in-furrow at planting (26%) compared with nontreated checks (48%). In-season fungicides were excluded from five of the experiments, whereas the 2018 Quincy, FL, experiment included eight applications on a 15-day interval. Across individual experiments, significant suppression of defoliation caused by late leaf spot was observed from 64 to 147 days after planting. Although more variable within location-years, pod yield following phorate treatment was overall significantly greater than for nontreated peanut (2,330 compared with 2,030 kg/ha; P = 0.0794). The consistent defoliation suppression potential was estimated to confer an average potential net economic yield savings of $90 to $120 per hectare under analogous leaf spot defoliation. To our knowledge, these are the first data in the 61 years since its registration demonstrating significant suppression of leaf spot on peanut following application of phorate in-furrow at planting. Results support phorate use in peanut as an effective and economical tactic to incorporate to manage late and early leaf spot infections and development of fungicide resistance.

Organophosphate, carbamate and pyrethroid pesticides are the most common insecticides used worldwide. They may cause chronic poisoning in farmers and acute poisoning in homicidal or suicidal cases. The determination of trace levels of these pesticides in human blood and urine is very challenging. This study focuses on a simultaneous quantitation method that was developed and validated for multi-class nine pesticides belonging to organophosphate, carbamate and pyrethroid classes in human blood and urine. Target pesticides were extracted from blood and urine using a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction method. Capillary column DB-35 ms (15 m × 0.25 mm, 0.25 µm) was used for chromatography with a 0.079 ml/min flow rate of carrier gas at constant pressure mode. Quantitation of sulfotep, phorate, carbofuran, chlorpyriphos, profenophos, triazophos, pyriproxyfen, lambda-cyhalothrin and permethrin was performed by mass spectrometer equipped with electron impact ionization source using selected ion monitoring (SIM) mode. The lower and upper limits of quantitation for all nine pesticides were 0.01 mg/L and 2.0 mg/dL respectively. The proposed method was proved to be simple, fast, sensitive, and robust. It has been applied to the analysis of 9 pesticides samples.

BACKGROUND Resistance to the dinitroaniline herbicide trifluralin in Lolium rigidum (annual ryegrass) often is mediated by the enhanced capacity to metabolize the herbicide to less toxic polar conjugates and/or by functionally recessive target-site mutations in α-tubulin. RESULTS In two L. rigidum populations possessing enhanced trifluralin metabolism, resistance was largely reversed by recurrent selection with the thiocarbamate herbicide prosulfocarb (i.e. plant survival was two- to >20-fold lower). Their ability to metabolize trifluralin was significantly decreased (by ≈2.3-fold) following recurrent prosulfocarb selection, to levels comparable to those observed in susceptible plants or when trifluralin metabolism was inhibited by treatment with the insecticide phorate. CONCLUSIONS This study provides evidence that trait(s) enabling efficient trifluralin metabolism in L. rigidum are purged from the population under prosulfocarb recurrent selection. The level of trifluralin metabolism in vitro and its inhibition caused by phorate action on trifluralin-metabolizing enzyme(s) is equivalent to the effect produced by prosulfocarb selection. The hypothetical link between the two phenomena is that the putative monooxygenase(s) conferring trifluralin metabolic resistance also mediate the activation of prosulfocarb to its toxic sulfoxide. Thus, we speculate that survival to prosulfocarb via a lack of metabolic herbicide activation, and survival to trifluralin conferred by enhanced herbicide metabolism, are mutually exclusive. These findings not only open up a new research direction in terms of the interaction between different herbicide resistance mechanisms in L. rigidum, but also offer strategies for immediate management of the population dynamics of metabolism-based resistance in the field. © 2020 Society of Chemical Industry.

Background The toxicity test has been developed to examine the effects of pesticides on fertilization and early development of marine polychaete Hydroides elegans (H. elegans). The pesticides lead to pollution of the ground water, aquatic environments and also marine environment. It directly enters the food chains of the organisms, and it affects the marine ecosystems. The pesticides alter the regular functions of the marine organisms as well as the physiological structure. Results The toxic effect of phorate on fertilization, early developmental stages of H. elegans, was examined, and it was found that the rate of successful development of embryonic development decreased when the concentration of phorate increased in sea water. The results present here strongly suggest that the mechanism of action of the pesticide probably acts on several intracellular targets based on EC50 values of the present study. It indicates that phorate was most toxic to the early developmental stages of H. elegans. Conclusion The results indicate that the early development of H. elegans is highly sensitive to phorate. The sedentary polychaete, Hydroides elegans, can be routinely used as a test organism for eco-toxicity bioassays at tropical and subtropical regions.

Although cadusafos, an aliphatic organophosphorus (OP) insecticide, is not approved by the European commission, it is used in several countries and sometimes detected as a residue in soils and agricultural products. In this study, two cadusafos-degrading Sphingobium sp. strains, K22212 and Cam5-1, were isolated and characterized for use as detoxifying agents of the insecticide. Both strains degraded 100 mg L−1 of cadusafos in mineral medium within 12 h through a common metabolite, which was supposed to be dimerized thiophosphates based on its molecular weight. Degradation of cadusafos increased cell growth for Cam5-1 but not for K22212. K2212 and Cam5-1 degraded cadusafos in soil (15 mg kg−1 dry soil) within 5 and 2 days, respectively. Both strains also degraded ethoprophos, phenthoate and phorate but not chlorpyrifos and diazinon, indicating that they are specialized for degradation of OP insecticides with at least one single bond connecting phosphorus and sulfur atoms (P S bond). For both strains, the degradation rate was the largest for ethoprophos, followed by cadusafos, phenthoate, and phorate. Our results indicate that these bacterial strains are effective degraders of OP insecticides with P S bonds, and in particular, Cam5-1 is more promising for removal of the OP insecticides in soils.

Planting date can affect pest incidence and severity in peanut. Research was conducted from 2013 to 2016 in North Carolina to determine tobacco thrips [Frankliniella fusca (Hinds)] injury and pod yield when peanut was planted in early, mid-, and late-May when phorate was applied in the seed furrow at planting, acephate was applied to emerged peanut 3 wk after planting, or when both insecticides were applied. Differences in visible injury to peanut caused by tobacco thrips feeding were observed across yr, planting dates, and insecticide treatments. Applying either phorate or acephate was often as effective as the combination of both insecticides in preventing injury caused by tobacco thrips although in some instances applying both insecticides was more effective than a single insecticide. Visible injury caused by tobacco thrips was often greater when peanut was planted in early May compared with later plantings. Peanut yield was protected equally from tobacco thrips injury by phorate, acephate, and the combination of both insecticides. Planting date and insecticides affected peanut yield independently suggesting that strategies for managing tobacco thrips will not differ across planting dates in North Carolina. Peanut yield was greater in 2 of 4 yr when planted in mid-May compared with planting in early or late-May.

The present field experiment was conducted to evaluate the efficacy of bio agents and chemical nematicides viz. Trichoderma harzianum, Pseudomonas fluorescens, Bacillus subtilis, Carbofuran 3G and Phorate 10G for management of rice root-knot nematode Meloidogyne graminicola during kharif-2014, 2015 and 2016. The present findings revealed that all the treatments were significantly superior over control with respect to plant growth parameters and nematode population. In control, terminal and spiral galls developed on rice roots, and plants suffered 32-41% decrease in the plant growth parameters and resulted upto 27% yield loss. At harvest greater decrease in soil population was recorded after soil application of T. harzianum (51.11%) followed by carbofuran 3G (46.82%). T. harzianum and carbofuran 3G were at par in suppression of root gall and egg mass suppression and T. harzianum caused 61.11 and 58.28% reduction in root gall and egg mass respectively, whereas, carbofuran 3G caused 59.52% and 62.50% reduction in root gall and egg mass respectively.

An experiment was conducted at Zonal Agricultural Research Station, V.C farm, Mandya (Karnataka), India during 2015, to assess the chemical control of sugarcane early shoot borer (Chilo infuscatellus). Nine insecticides namely, Fipronil 0.3G, Chlorantraniliprole 0.4G, Chlorantraniliprole 18.5 SC, Spinosad 45SC, Flubendiamide 39.35SC, Cartap hydrochloride 4G, Phorate 10G, Carbofuran 3G, Chlorpyriphos 20EC, and compared with untreated (Check plot)using randomized block design with three replications. Significant differences were noticed among the treatments. Chlorantraniliprole 0.4G recorded lowest cumulative incidence (2.79 %) and highest per cent reduction over the control (85.78 %) which was followed by Cartap hydrochloride 4G (5.37% and 72.65%), Chlorantraniliprole 18.5 SC (5.95% and 75.62%), Flubendiamide 39.35SC (6.64% and 66.19%) and Fipronil 0.3G (6.83% and 65.22%) were found significantly superior in reducing the cumulative incidence of C. infuscatellus.In Co 86032 Cartap hydrochloride 4G was found to be the best insecticide in getting a highest cost benefit ratio (1:12.39). Other insecticides such as Fipronil 0.3G (1:8.84), Chlorantraniliprole 0.4G (1:6.96), Flubendiamide 39.35SC (1:5.42) and Spinosad 45SC (1:4.16) have also recorded better cost benefit ratio. Since Cartap hydrochloride 4G does not have crop label so we can recommend Fipronil 0.3G or Chlorantraniliprole 0.4G for the management of sugarcane early shoot borer.

Phorate is a highly toxic agricultural pesticide currently in use throughout the world. Like many other organophosphorus (OP) pesticides, the primary mechanism of the acute toxicity of phorate is acetylcholinesterase (AChE) inhibition mediated by its bioactivated oxon metabolite. AChE reactivation is a critical aspect in the treatment of acute OP intoxication. Unfortunately, very little is currently known about the capacity of various oximes to rescue phorate oxon (PHO)-inhibited AChE. To help fill this knowledge gap, we evaluated the kinetics of inhibition, reactivation, and aging of PHO using recombinant AChE derived from three species (rat, guinea pig and human) commonly utilized to study the toxicity of OP compounds and five oximes that are currently fielded (or have been deemed extremely promising) as anti-OP therapies by various nations around the globe: 2-PAM Cl, HI-6 DMS, obidoxime Cl 2 , MMB4-DMS, and HLo7 DMS. The inhibition rate constants ( k i ) for PHO were calculated for AChE derived from each species and found to be low (i.e., 4.8 × 10 3 to 1.4 × 10 4 M − 1 min − 1 ) compared to many other OPs. Obidoxime Cl 2 was the most effective reactivator tested. The aging rate of PHO-inhibited AChE was very slow (limited aging was observed out to 48 h) for all three species. Conclusions: (1) Obidoxime Cl 2 was the most effective reactivator tested. (2) 2-PAM Cl, showed limited effectiveness in reactivating PHO-inhibited AChE, suggesting that it may have limited usefulness in the clinical management of acute PHO intoxication. (3) The therapeutic window for oxime administration following exposure to phorate (or PHO) is not limited by aging.

In the current study, experimental (UV–visible, Fourier transform infrared [FTIR], 1H-NMR and scanning electron microscope) and computational (UV–visible, FTIR, 1H-NMR, HOMO–LUMO, steric and geometric parameters) analyses of acephate, glyphosate, monocrotophos and phorate were performed for the first time. Computational studies were performed at the HF/6–311G(d,p) level of theory. It was found that experimental values of UV–visible, FTIR, 1H-NMR and geometric data were in very good agreement with the computational ones. The current study may assist future studies, like spectral analysis, pesticide(s) detection, surface behaviour and decomposition analysis of top selling titled pesticides of world market.

The ingestion of organophosphate (Op) pesticides for attempting suicide has been a serious health issue recently. Phorate, a class of Op, has attracted attention in this regard and so the rapid diagnosis and detection of phorate is crucial for human health. In this study, a one-step and visual method for the rapid determination of phorate via an aptasensor based on DNA-templated silver nanoclusters (DNA–AgNCs) has been presented. The designed DNA–AgNC nanoprobe, containing a special structure with an intercalated aptamer, shows excellent stability. Introducing phorate to the system easily triggers the aggregation of DNA–AgNCs, producing a brown-to-colorless color change in the solution in only 6 minutes. Under the optimal conditions, the aptasensor can allow for the determination of phorate in the concentration range of 0–25 μg mL−1, using two linear equations: y = −2.308x + 0.996 (R2 = 0.977) for 0–0.125 μg mL−1 and y = −0.020x + 0.664 (R2 = 0.971) for 0.125–25 μg mL−1. The estimated detection limit of phorate was 0.012 ng mL−1. Moreover, the practicability of this proposed method was also validated by analyzing phorate-spiked human blood samples and the results were in agreement with those from gas chromatography/mass spectrometry (GC/MS) analysis. Therefore, this fabricated aptasensor is suitable for sensing phorate in complex biological samples, and shows high potential for clinical diagnosis or forensic toxicology analysis.

The development of solid phase extraction (SPE) combined with the sensitive detection of surface-enhanced Raman spectroscopy (SERS) has been successfully applied for the analysis of complex environmental samples. In this work, a silver nanoplate-decorated copper membrane was fabricated as a recyclable SERS-active SPE substrate. The membrane was fabricated via modified galvanic displacement on a commercial copper membrane. Compared with filter paper SERS substrates, the as-synthesized substrate has relatively rapid heat conduction, which can lead to a greater temporal stability under continuous laser irradiation conditions. The relative standard deviation (RSD) value of the intensity change is 0.31%. The experimental results also showed that these substrates have a long life and are reproducible even after 5 cycles. The RSD was calculated to be 12.13%, which indicates that this method was recyclable. The signal intensity of filtering is almost 28 times higher than that of the traditional dropping method, which proves that the membrane has rapid extraction ability. The qualitative and quantitative detection of phorate was investigated based on a flow-through method. A good linearity (R2 = 0.98) was achieved for phorate in the concentration range of 3.84 to 288 nmol L−1. In addition, the simulated detection of phorate in actual water such as underground water, surface water, and drinking water was also studied. These results demonstrated its practical application to rapidly detect phorate in the real environment.

This study investigated the levels of highly toxic pesticides (HTPs) in 6554 vegetable and fruit samples from 31 regions of China, along with the associated risk of dietary exposure for the population between 2014 and 2017. 18 HTPs were detected in 325 (4.96%) samples, and the levels of HTPs in 103 (1.57%) samples were found to be higher than the maximum residue limits (MRLs) of China. The rate of detection of HTPs in six types of vegetables and fruits, in a decreasing order, was found to be as follows: eggplant (8.84%) >grape (5.58%) >tomato (5.43%) >cucumber (5.43%) >pear (3.12%) >apple (2.30%). The level of contamination of HTPs was found to be higher in vegetables compared with fruits. The vegetable and fruit samples with the highest percentages of HTPs exceeding MRLs were found in eggplants from Guangxi (20%) and grapes from Inner Mongolia (12.5%), respectively. Both, the average target hazard quotient (THQ) of a single highly toxic pesticide (HTP) and the average hazard index (HI) of the mixture of HTPs for adults and children from vegetables and fruits from the 31 regions were found to be less than one. Omethoate, carbofuran, ethoprophos, triazophos, and phorate were identified as the major contributors to the average HI for vegetables, and carbofuran, ethoprophos, omethoate, phorate, and phosphamidon were identified as the primary contributors to the average HI for fruits. The results of this study revealed that HTPs in vegetables and fruits did not cause any significant chronic risk of dietary exposure. The detection of HTPs exceeding MRLs in some of the samples implied that appropriate management guidelines for HTPs should be implemented to protect the health of the consumers.

The effects of alkaline and acidic electrolyzed water (AlEW, AcEW) treatment on the removal of pesticides (phorate, chlorpyrifos, lambda-cyhalothrin, cyfluthrin, procymidone, and chlorothalonil) and texture quality of fresh-cut cabbage, broccoli, and color pepper were investigated. AlEW efficiently removed pesticides from color pepper, whereas AcEW was the optimal treatment for pesticide removal from cabbage and broccoli. AcEW resulted in greater losses of pyrethroid and organophosphates than fungicides, while AlEW was superior for removing fungicides. The best pesticide removal from cabbage (72.28%–91.04%) was achieved by continuous oscillation treatment, while intermittent oscillation for 20 min achieved optimal results for broccoli and color pepper (72.28%–90.11% and 72.24%–88.12%, respectively). No significant deterioration in texture was detected in samples treated with electrolyzed water for 5–25 min. The results suggest that electrolyzed water treatment is effective for removing organophosphate, pyrethroid, and fungicide residues from fresh-cut vegetables while not negatively affecting their texture quality.

Biocides (herbicides and insecticides) are intensively being used in rice cultivation, despite several adverse non-target effects on native cyanobacteria. Comparative effects of three herbicides (benthiocarb, butachlor, and 2,4-D) and four insecticides (furadon, phorate, methyl parathion, and ekalux) were studied at field-recommended doses. Field experiments of rice were carried out for three consecutive seasons in completely randomized block designs in both rainy and winter croppings at the Central Rice Research Institute, Cuttack, India. Toxicities of seven biocides individually to native cyanobacteria growing with rice crops in wetland fields were assessed for growth and acetylene reduction activity (ARA); several crop parameters of paddy were estimated concomitantly. It was observed that applications of butachlor and benthiocarb individually significantly decreased growth (15.86 and 17.50%), ARA (0.16 and 0.68%), and N-yield (0.26 and 0.85%) of the native cyanobacteria, whereas these parameters increased (24.04% in growth, 0.25% in ARA, and 0.40% in N-yield) due to the application of 2,4-D. Of the tested insecticides, furadon, phorate, and methyl parathion enhanced the growth (17.8, 10.7, and 11.7%), N2-fixation (0.10, 0.097, and 0.074%), and N-yield (0.16, 0.18, and 0.20%) of cyanobacteria, whereas ekalux had no significant effect on cyanobacteria. On the basis of cyanobacterial parameters, biocides could be recommended for rice crops in the order furadon < phorate < methyl parathion < ekalux. Applications of 2,4-D and furadon individually in comparison to the rest other biocides enhanced rice yield. These finding could help to revise integrated strategies of weed and pest management in wetland rice agriculture to save non-target soil microorganisms, particularly cyanobacteria.

Detection of organophosphorus pesticides (OPPs) is crucial for food safety and environmental protection. Here, we propose an enzyme-free strategy for the detection of phosphorothiolate pesticides, a major class of OPPs with P–S bonds, by using hyaluronan–tyrosine–gold nanoparticles (HA–Tyr–AuNPs) as the colorimetric probe. The strategy is based on the concept that the surface of AuNPs can be directly modified by the hydrolyzate of the phosphorothiolate in a strongly basic HA–Tyr–AuNP colloidal solution, which in turn affects the aggregation state of AuNPs and hence produces a red-to-blue color change. This method is very simple in design and easy to operate. The detection requires only the addition of the analyte into the HA–Tyr–AuNP colloidal solution at room temperature. By virtue of the absorbance variations of the analytical system, the limit of detection for phorate is as low as 0.005 μg mL−1 (i.e., 0.006 mg kg−1), which is lower than the maximum residue limit (MRL) allowed by the European Union. More importantly, phorate residues in real samples can be directly detected by this method.

Sixteen bacterial isolates were obtained from insecticide treated tomato, brinjal maize and ground nut rhizospheric soils by enriching Mineral Salt Medium broth with supplement of chlorpyrifos, Phorate source. These isolates were characterized on the basis of cell morphology, cultural and biochemical properties. Among the eight chlorpyrifos degrading bacterial isolates, CDB-1isolate utilized the more pesticide. Among the eight phorate degrading bacterial isolates, the Phorate degrading bacteria (PDB)-1 isolate utilized the pesticide (Phorate) effectively. Degrading efficiency of isolates was determined by measuring the chlorpyrifos, phorate residual concentrations at intervals using Gas chromatographic method. Among the molecular diversity of 16 organophosphorus pesticide degrading isolates viz., chlorpyrifos degrading isolates 8, phorate degrading isolates 8 were also studied by PCR-RAPD technique. CDB7 shows separate lane with 26 per cent similarity compared to other isolates. CDB5 isolate shows 29 per cent similar when compared with other samples. CDB3 and CDB4 reveal same genetic relatedness according to dendrogram. CDB2 and CDB6 showed 54 percent similarity and CDB1 shows 41 percent similarity. CDB3 and CDB4 isolates are more or less similar in the genome and functional properties. Whereas, CDB7 isolate was highly diverse among other isolates.. PDB5 and PDB6 showed 55 per cent similar in coefficient scale. Whereas PDB2 and PDB3 revealed 75 per cent relatedness. The other isolates, PDB1, PDB7 and PDB4 shows 64–66 per cent similar. The PDB8 was highly diverse from remaining other seven isolates. PDB2 and PDB3 showed similar genome and functional properties.

Background Multiple-herbicide resistance in Lolium rigidum and other weed species is increasingly exerting pressure on herbicide discovery research for solutions against resistance-prone weeds. In this study we investigate: (i) the responses of L. rigidum populations and wheat to the new herbicide cinmethylin in comparison with other pre-emergence herbicides, (ii) the effect of seed burial depths on cinmethylin efficacy and crop selectivity, and (iii) the basis of cinmethylin selectivity in wheat. Results Cinmethylin at 400 g ha-1 controls herbicide-susceptible and multiple-resistant L. rigidum, with a reduction of >85% in plant emergence and 90% in aboveground biomass. Cinmethylin provides effective control of a large number of field populations of L. rigidum with evident resistance to trifluralin. When the wheat seed is buried ≥1 cm below the cinmethylin-treated soil surface, the emergence of crop seedlings is not different from the untreated control. The organophosphate insecticide phorate synergizes cinmethylin toxicity in wheat, with an LD50 of 682 g ha-1 in the absence of phorate versus 109 g ha-1 in the presence of phorate (84% reduction). The synergistic effect of phorate with cinmethylin on herbicide-susceptible L. rigidum appears smaller (a 44% reduction in the LD50 of cinmethylin). Conclusions Cinmethylin is effective in controlling multiple-resistant L. rigidum and appears safe for wheat when the seed is separated at depth from the herbicide applied to the soil surface. The basis of this metabolism-based selectivity is likely regulated by cytochrome P450 monooxygenases. © 2020 Society of Chemical Industry.

For decades, organophosphate (OP) insecticides have been used as chemical control agents in watersheds that support at-risk populations of Pacific salmon throughout western North America. Spray drift, runoff, and other processes transport OPs to critical surface water habitats for migratory salmonids. While most OPs share a common mechanism of action (i.e., inhibition of neuronal acetylcholinesterase, or AChE), they typically vary in toxic potency. Moreover, dose-response relationships for exposure and sublethal neurotoxicity (e.g., brain AChE inhibition) in salmonids have not been defined for many OPs. Here we exposed juvenile coho salmon (Oncorhynchus kisutch) to five common anticholinesterase insecticides (dimethoate, ethoprop, naled, phorate and phosmet) that are widely used on agricultural, commercial, residential, and public lands. Each of the five pesticides produced a concentration-dependent inhibition of AChE enzyme activity. The effective concentration for 50 % AChE inhibition (96-hr EC50) indicated the highest toxicity for phorate (EC50 = 0.57 μg/L) followed by phosmet (3.3 μg/L), naled (7.8 μg/L), ethoprop (90.6 μg/L) and dimethoate (273 μg/L). These findings can inform 1) relative hazard analyses for OP use near sensitive aquatic habitats, 2) predictions of sublethal OP mixture toxicity, and 3) ecological risk assessments for threatened or endangered species of Pacific salmon.

Herein, we studied phorate for its toxicological effects in human lymphocytes. Phorate treatment for 3 h has induced significant increase in the lymphocytic DNA damage. Compared to control, comet data from highest concentration of phorate (1000 µM) showed 8.03-fold increase in the Olive tail moment (OTM). Cytokinesis blocked micronucleus (CBMN) assay revealed 6.4-fold increase in binucleated micronucleated (BNMN) cells following the exposure with phorate (200 µM) for 24 h. The nuclear division index (NDI) in phorate (200 µM) treated cells reduced to 1.8 vis-à-vis control cells showed NDI of 1.94. Comparative to untreated control, 60.43% greater DCF fluorescence was quantitated in lymphocytes treated with phorate (500 µM), affirming reactive oxygen species (ROS) generation and oxidative stress. Flow cytometric data of phorate (200 µM) treated lymphocytes showed 81.77% decline in the fluorescence of rhodamine 123 (Rh123) dye, confirming the perturbation of mitochondrial membrane potential (ΔΨm). Calf thymus DNA (ct-DNA) treated with phorate (1000 µM) exhibited 2.3-fold higher 8-Hydroxy-2′-deoxyguanosine (8-oxodG) DNA adduct formation, signified the oxidative DNA damage. The alkaline unwinding assay revealed 4.0 and 6.5 ct-DNA strand breaks when treated to phorate and phorate-Cu (II) complex. Overall, the data unequivocally suggests the cyto- and genotoxic potential of phorate in human lymphocytes, which may induce comparable toxicological consequences in persons occupationally or non-occupationally exposed to insecticide phorate. Keywords: Phorate, DNA damage, Micronuclei, Oxidative stress, Lymphocytes, Insecticides

Phorate is a systemic organophosphorus pesticide (OP) that acts by inhibiting cholinesterases. Recent studies have reported that long-term low/moderate exposure to OP could be correlated with impaired cardiovascular and pulmonary function and other neurological effects. A 70-year-old farmer died after an intention ingestion of a granular powder mixed with water. He was employed on a farm for over 50 years producing fruit and vegetables, and for about 20 years, he had also applied pesticides. In the last 15 years, he used phorate predominantly. The Phorate concentration detected in gastric contents was 3.29 µg/mL. Chronic exposure to phorate is experimentally studied by histopathological changes observed in the kidney. In the light of current literature, our case confirms that there is an association between renal damage and chronic exposure to phorate in a subject exposed for years to the pesticide. Autopsies and toxicological analyses play a key role in the reconstruction of the dynamics, including the cause of the death.

BACKGROUND Organophosphate insecticides can inhibit specific cytochrome P450 enzymes involved in metabolic herbicide resistance mechanisms, leading to synergistic interactions between the insecticide and the herbicide. In this study we report synergistic versus antagonistic interactions between the organophosphate insecticide phorate and five different herbicides observed in a population of multiple herbicide-resistant Lolium rigidum. RESULTS Phorate synergised with three different herbicide modes of action, enhancing the activity of the ALS inhibitor chlorsulfuron (60% LD50 reduction), the VLCFAE inhibitor pyroxasulfone (45% LD50 reduction) and the mitosis inhibitor trifluralin (70% LD50 reduction). Conversely, phorate antagonised the two thiocarbamate herbicides prosulfocarb and triallate with a 12-fold LD50 increase. CONCLUSION We report the selective reversal of P450-mediated metabolic multiple resistance to chlorsulfuron and trifluralin in the grass weed L. rigidum by synergistic interaction with the insecticide phorate, and discuss the putative mechanistic basis. This research should encourage diversity in herbicide use patterns for weed control as part of a long-term integrated management effort to reduce the risk of selection of metabolism-based multiple herbicide resistance in L. rigidum. © 2016 Society of Chemical Industry