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During Kharif season of 2022, the experiment entitled "Field efficacy of selected insecticides against fall armyworm, Spodoptera frugiperda (J.E. Smith) on maize (Zea mays L.) at Prayagraj" was carried out at Central Research Farm, Sam Higginbottom University of Agriculture, Technology And Sciences, Naini, Prayagraj, India. Eight treatments T1) Indoxacarb 14.5 SC @ 0.85 ml/l, T2) Spinetoram 11.7 SC @ 0.5 ml/l, T3) Azadirachtin 0.15% @ 5 ml/l, T4) Nisco sixer plus @ 1 ml/l, T5) Lambda-cyhalothrin 5 EC @ 0.64 ml/l, T6) Cypermethrin 25 EC @ 2 ml/l, T7) Fipronil 0.6% G @ 0.12 ml/l and T8) Control (water spray) were evaluated for their effectiveness against S. frugiperda. Each insecticide were applied twice, between 15 days of interval. The population of larvae on each plant were counted the day before, and 3, 7 and 14 days after each spray. When compared to control (water spray) all treatments tested significantly reduced the larval population of S. frugiperda. Among the insecticides tested, spinetoram 11.7 SC @ 0.5 ml/l was found to be very effective in lowering larval population followed by indoxacarb 14.5 SC @ 0.85 ml/l and lambda-cyhalothrin 5 EC @ 0.64 ml/l, with larval populations of 3.17, 3.36, and 3.84, respectively. Whereas, the other treatments viz., cypermethrin 25 EC @ 2 ml/l with 4.05, fipronil 0.6% G @ 0.12 ml/l with 4.31, Nisco sixer plus @ 1 ml/l with 4.79 and azadirachtin 0.15% @ 5 ml/l with 5.21 were next in the order of efficacy. [ABSTRACT FROM AUTHOR]

The regular monitoring of status of acaricide resistance by various techniques build the backbone of tick control programmes. The one host tick, Rhipicephalus microplus is the most common cattle tick responsible for several health hazards (babesiosis and anaplasmosis) and economic losses to the organized livestock farms in India. The present manuscript aimed to determine the status of acaricide resistance against multiple chemical acaricides, which are commonly used by livestock owners. The rapid and simplified FAO recommended adult immersion test with discriminating dose (AIT-DD) bioassay has been used to encourage the continuus field level monitoring of status of acaricide resistance. Out of the 20 isolates collected from 8 districts belonging to arid and semi-arid zone of Haryana, resistance against deltamethrin (40–100%), cypermethrin (26.67–100%), coumaphos (6.67–26.67%), fipronil (3.33-40.0%) and amitraz (6.67-80%) were recorded in 90%,75%, 20%, 40% and 35% isolates, respectively. All the isolates showed complete susceptibility to the flumethrin treatment. Data generated revealed a notable variance of susceptibility to synthetic pyrethroid and formamidine drugs in the R. microplus population of arid and semi-arid zone of Haryana. This study records the first attempt to monitor the status of acaricide resistance in ticks against all the available acaricides. Data generated can be used as an indicator for the management of one host tick in the state. [ABSTRACT FROM AUTHOR]

Pesticide poisoning is one of the most common instances of poisoning deaths in every agriculture-dependent country may it be in form of suicidal or homicidal cases. Traditional classes of pesticides like the Organophosphates, Organochlorides and Carbamates have given way to the newer class of pesticides known as synthetic Pyrethroids. Some of the synthetic Pyrethroids like Cypermethrin, Deltamethrin and Fenavalerate are increasingly being encountered as routinely used poisons in rural India. In the instance of poisoning detecting the class of Pyrethroids uses a complex and costly instruments which is not very user friendly and also expensive. In the present article Thin Layer chromatography which is classical method of seperation science has been used as tool to identify the class of Pyrethroids, identification of Cypermethrin pesticide is analyzed using different solvent system for qualitative analysis with suitable spray reagent to identify the movement of the spot. [ABSTRACT FROM AUTHOR]

Studies were carried out during 2021-2022 to evaluate toxicity levels of different insecticides against larvae of bamboo leaf roller Pyrausta coclesalis (Lepidoptera: Pyraustidae) are one of the most important group of leaf feeders on bamboo (Family: Poaceae) in Central India. Spinosad 45 SC (0.03%), profenofos 50 EC (0.04%), Cypermethrin 25 EC (0.03%), fenvalerate 20 EC (0.03%), chlorantraniliprole 18.5 SC (0.03%) and bio pesticide Azadirachtin 10000 PPM (0.05%) at the recommended concentration was evaluated against of bamboo leaf roller at the Division of Forest Protection, Tropical Forest Research Institute, Jabalpur, Madhya Pradesh, India. The study revealed that spinosad 45 SC (0.03%), profenofos 50 EC (0.03%) and cypermethrin 25 EC (0.03%) were effective with the maximum larval mortality of 91.66, 83.33 and 75 percent at 72 hours after treatment followed by fenvalerate 20 EC (0.03%) and Chlorantraniliprole 18.5 SC (0.03%) which recorded similar mortality of 66.66 were at par to each other at the same period of observation. Among bio pesticide azadirachtin (0.05%) treatment recorded least larval mortality of leaf roller 58.33 percent at 72 hours after treatment. [ABSTRACT FROM AUTHOR]

The resistance status against deltamethrin, cypermethrin, coumaphos and ivermectin was assessed of Rhipicephalus microplus from five districts of Uttarakhand, through adult immersion test and larval packet test. The field isolates were highly resistant to deltamethrin (median resistance ratio [RR50] = 9.10–29.13-fold) followed by cypermethrin (2.23–3.55). Surprisingly the isolates were susceptible to coumaphos (0.34–3.17). Emerging resistance against ivermectin (1.55–3.27) was also observed in all the isolates. Elevated levels of esterases (enzyme ratio = 2.93–5.84-fold), glutathione S-transferases (5.10–10.06) and monooxygenases (1.68–4.02) in resistant fields isolates were highly correlated (47.4–86.0%) with the resistant factor (RR50) determined by bioassay. All the isolates except Uttarkashi possess mutation at the 190th position in domain II of the sodium channel gene. As a mitigation strategy an Ageratum conyzoides-based characterized natural formulation was tested against all the isolates and was found effective at the concentration of 10.1–11.5%. The possibility of using the natural formulation for the management of multi-acaricide resistant ticks is discussed. [ABSTRACT FROM AUTHOR]

This study examined the pattern of resistance to widely applied synthetic pyrethroids, i.e., cypermethrin and deltamethrin, against larvae of Rhipicephalus microplus ticks sampled from Marathwada region in Maharashtra, India. The study also examined the role of α- and β-esterases and glutathione-S-transferase (GST) in resistance development. All eight R. microplus isolates tested were resistant to deltamethrin (RL IV), having RR 50 values from 6.88 to 131.26. LPT analysis exhibited the resistance level II deltamethrin resistance in Beed and Hingoli, III in Dharashiv, and IV in Sambhajinagar, Parbhani, Latur, Jalna, and Nanded isolates. The LIT analysis showed that Dharashiv field isolates had the lowest LC 50 value of 229.09 ppm against cypermethrin, while Sambhajinagar field isolates had the highest at 489.78 ppm. The RR 50 ranged from 1145.45 to 2448.9. Seven isolates were level I resistant to cypermethrin while the Jalna isolate was level II resistant. In larvae treated with deltamethrin and cypermethrin, the activity of α- and β-esterase enzymes increased significantly compared to control groups. The enzyme ratios in treated larvae ranged from 0.7533 to 1.7023 for α-esterase and 0.7434 to 3.2054 for β-esterase. The Hingoli isolate treated with cypermethrin exhibited the highest α-esterase activity (903.261), whereas Sambhajinagar isolate had the highest GST enzyme ratio (2.8224) after deltamethrin exposure. When exposed to cypermethrin, the Hingoli isolate showed the highest GST enzyme ratio, 2.0832. The present study provides the current resistance status in tick populations from Marathwada region indicating deltamethrin and cypermethrin to be ineffective for tick control. The results also suggest that SP compounds should be regulated in this region and alternative control strategies should be introduced., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Sapota, a prominent and economically important fruit crop of India is susceptible to several species of insect and mite pests. Several pesticides formulations are used to control the pest damage in sapota. The present investigation was aimed to study the dissipation and persistence behaviour of combi-product profenofos 40% + cypermethrin 4% (44EC) at the standard dose (SD) (1162 g a.i. ha-1+106 g a.i. ha-1) and double to standard dose (2×SD) (2324 g a.i. ha-1+212 g a.i. ha-1) in/on sapota under tropical agro-climatic conditions of South Gujarat in India. Prior to quantitative analysis of pesticide residue on Gas chromatography with electron captured detector (GC-ECD), the modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) based method was validated on its accuracy, precision, linearity and sensitivity. Profenofos persisted in sapota up to 30 days with the half-lives of 5.65 and 7.34 days at SD and 2×SD, respectively. Cypermethrin dissipated at a rapid pace and was below quantitation limit (BQL) on 7 days at either dose of application; the half-life values recorded were 3.27 and 4.43 days at SD and 2×SD, respectively. This is the first case study that reflects 14 days as a waiting period after the last spray of combi-product (44EC) at standard dose facilitates the residuefree sapota fruits. Further, the health risk index (HRI<1) and Health Index (HI %< 100%) indicates that the application of combi-product profenofos 40% + cypermethrin 4% (44EC) at standard dose could not pose any health risk to Indian consumers. [ABSTRACT FROM AUTHOR]

Regular monitoring of the status of acaricide resistance in field ticks is the need of the hour. Synthetic pyrethroids (cypermethrin and deltamethrin) are most commonly used acaricides against field ticks. There is bulk of literature on development of deltamethrin resistance; however, scarce information is available regarding current status of cypermethrin efficacy against field ticks. In the present study, the cypermethrin resistance status in Rhipicephalus microplus and Hyalomma anatolicum ticks infesting cattle and buffaloes of five districts located in the Northern Indian state, Haryana was determined using larval packet test. The linear regression graphs of probit mortality of tick larvae were plotted against log concentrations of cypermethrin to determine the slope of mortality, LC50, LC95 and the resistance factor (RF).Seven isolates of R. microplus were found resistant with their RF ranges from 1.83 to 25.35, whereas, 5 isolates of H. anatolicum were recorded as resistant with their RF ranging from 1.54 to 2.56 indicating a slower pace of development of cypermethrin resistance in multi-host ticks. Jarwa isolate of R. microplus and Dhangar isolate of H. anatolicum was found susceptible (RF < 1.5) to cypermethrin. The RF values of Agroha and Siwani isolate of R. microplus (10.73 and 25.35) were much higher as compared to other isolates indicating an urgency to address the growing cypermethrin resistance problem at grassroots level. Data generated in the present technical program could be of enormous help in formulating a suitable strategy against ticks and tick-borne infections of humans and animals. [ABSTRACT FROM AUTHOR]

Raw buffalo, cow and goat milk collected from different locations of Northern India has been analyzed for suspected pesticides viz. azimsulfuron, cypermethrin, thiabendazole, crotonolactone, fluoxastrobin, aldicarb and carbofuran. Buffalo milk tested positive for azimsulfuron (4.51 ng/ml), cypermethrin (7.21 ng/ml) and thiabendazole (4.57 ng/ml). Cow's milk did not show the presence of cypermethrin and thiabendazole, however, azimsulfuron (0.86 ng/ml), crotonolactone (4.73 ng/ml) and fluoxastrobin (0.54 ng/ml) were determined. Milk of the goats registered the presence of carbafuron (7.69 ng/ml), fluoxastrobin (5.41 ng/ml) and azimsulfuron (5.28 ng/ml). Since all the milching cattle are herbivorous, these pesticides entered animal through food chain. The consumption of milk containing these pesticides even in traces may be hazardous to human population of Northern India. Concurrent presence of these pesticides may be more hazardous due to their synergistic manifestations. New synthetic molecules like azimsulfuron, fluoxastrobin and crotonolactone may pose severe public health problems. [ABSTRACT FROM AUTHOR]

A fungal isolate Aspergillus terreus PDB-B (accession number: MT774567.1), which could tolerate up to 500 mg/L of cypermethrin, was isolated from the lake sediments of Kulamangalam tropical lake, Madurai, and identified by internal transcribed spacer (ITS) sequencing followed by phylogenetic analysis. The biotransformation potential of the strain was compared with five other strains (A, J, UN2, M1 and SM108) as a consortium, which were tentatively identified as Aspergillus glaucus , Aspergillus niger , Aspergillus flavus , Aspergillus terreus , and Aspergillus flavus , respectively. Batch culture and soil microcosm studies were conducted to explore biotransformation using plate-based enzymatic screening and GC-MS. A mycotransformation pathway was predicted based on a comparative analysis of the transformation products (TPs) obtained. The cytotoxicity assay revealed that the presence of (3-methylphenyl) methanol and isopropyl ether could be relevant to the high rate of lethality.

Organophosphorus insecticide (OPI) poisoning is a major health problem in India. These are irreversible inhibitors of acetyl cholinesterase which produce a well-established triphasic effect. The first phase which is a cholinergic phase due to increased action of acetylcholine at muscarinic, nicotinic and central nervous system synapses produces symptoms like Miosis, Blurred Vision, Nausea, Vomiting, Diarrhea, Salivation, Lacrimation, Bradycardia, Abdominal Pain (Muscarinic), Fasciculations, Paralysis, Pallor, Muscle Weakness, Hypertension, Tachycardia, Mydriasis (Nicotinic), Confusion, Toxic Psychosis, Seizure, Fatigue, Respiratory Depression, Dysarthria, Unconsciousness, Ataxia, Anxiety (Central Effects). The second phase is intermediate syndrome which sets in 2-4 days after initial exposure, the signs and symptoms comprise of muscle fasciculations and neuromuscular paralysis involving the respiratory, bulbar and limb muscles. The third phase is Organophosphorus Induced Delayed Polyneuropathy (OPIDN), which is often noted after 7-21 days of exposure, initial symptoms include paraesthesias, pain in calves, foot drop etc. In addition, extrapyramidal manifestations are also described after acute organophosphorus poisoning such as Dystonia, Rest Tremors, Cog Wheel Rigidity And Choreathetosis. Cypermethrin is a synthetic pyrethroid used as an insecticide. Studies suggested that long term exposure to cypermethrin induces nigrostriatal dopaminergic neurodegeneration in adult rats. Acute ingestion of cypermethrin will cause nausea, vomiting, stomach pain, convulsions, coma and death in humans. The etiology of parkinsonism is multi factorial with genetic, environmental and toxic determinants, development of typical parkinsonism after brief exposure to organophosphorus compounds is a rare phenomena and there are only few reports in literature. We report a 40 year old female who presented with cholinergic crisis following acute ingestion of Profofenos and Cypermethrin mixed compound, developed parkinsonism on day 5 of admission and recovered completely after 2 days of treatment with Amantidine. [ABSTRACT FROM AUTHOR]

• Indian freshwater ecosystems are not well studied, are degraded due to expansive agriculture and are contaminated with pesticides. • Mesocosms identified malathion was the dominant stressor among co-occurring stressors. • In mesocosms malathion reduced richness, organism densities and caused community homogenisation. • Toxicology test comparisons between countries identify that Indian taxa may be relatively pesticide tolerant. Globally, river pesticide concentrations are associated with regional and local stream invertebrate diversity declines. Pesticides often co-occur with elevated nutrients (e.g. nitrogen and phosphorus) and sediments related to agriculture, making their individual effects difficult to disentangle. These effects are also less well studied in Asia, than in other geographic regions. Within Asia, India is one of the largest producers and users of pesticides and has approximately 60% of total land mass used for agriculture. Here we examine the responses of Indian river invertebrate communities subjected to malathion, nutrients, and sediment additions in a semi-orthogonal design, in three sequential (through time) short-term (120 h) mesocosm experiments. Additionally, a series of single-species toxicity tests were run that used 24 h exposure and 72 h recovery to examine the sensitivity of 13 local invertebrate taxa to malathion, and 9 taxa to cypermethrin, comparing these results to those from other biogeographic regions. Mesocosm results indicate that malathion exposure had a major effect compared to other stressors on communities, with a lesser effect of nutrients and/or sediments. In mesocosms, taxa richness, total abundance and the abundance of sensitive species all declined associated with malathion concentrations. Comparisons of organism sensitivities from other geographic locations and those in the current paper suggest taxa in India are relatively tolerant to malathion and cypermethrin. Our results further reinforce that the high observed aquatic pesticide concentrations known to occur in Asian freshwater ecosystems are likely to be negatively affecting biodiversity, homogenising biota towards those most stress tolerant. [ABSTRACT FROM AUTHOR]

Background: Common pesticides used in the region by agricultural workers may cause contact allergy. Methods: Thirty agricultural workers with a history of pesticide exposure and dermatitis involving the face, neck, trunk or extremities, and 20 controls comprising 2 groups of 10 subjects each, group 1 with dermatitis and no exposure to pesticides, and group 2 with neither exposure to pesticides nor dermatitis, were patch tested with 10 pesticides commonly used in the region by use of the Finn Chamber method. Results: The 30 patients, 20 of whom were male, aged 30‐77 years, had dermatitis for 1 month to 18 years, with relapses and remissions. Seasonal exacerbation was present in 18 patients. Six patients attributed aggravation of their dermatitis to pesticide exposure, and 2 of these reacted positively to propiconazole. Positive patch test reactions to pesticides occurred in 10 patients, but not in controls. Thiuram was the commonest sensitizer (4 patients). Three patients were sensitized to propiconazole, and 2 patients reacted positively to metaldehyde. Formaldehyde, mercaptobenzothiazole, cypermethrin and isoproturon gave positive reactions in 1 patient each. Conclusion: The sensitizing potential of pesticides remains a concern. Apparently, pesticide contact dermatitis is more common than expected, but remains under‐reported, as the implicated pesticides vary across regions and according to the crop patterns. [ABSTRACT FROM AUTHOR]

India is one of the leading countries in production and indiscriminate consumption of pesticides. Owing to their xenobiotic nature, pesticides affect soil microorganisms that serve as mediators in plant growth promotion. Our study aimed to deliver a comprehensive picture, by comparing the effects of synthetic pesticides (chlorpyriphos, cypermethrin, and a combination of both) with a biopesticide (azadirachtin) at their recommended field application level (L), and three times the recommended dosage (H) on structure and function of microbial community in rhizosphere of Vigna radiata. Effect on culturable fraction was assessed by enumeration on selective media, while PCR-denaturing gradient gel electrophoresis (DGGE) was employed to capture total bacterial community diversity. This was followed by a metabolic sketch using community-level physiological profiling (CLPP), to obtain a broader picture of the non-target effects on rhizospheric microbial community. Although plant parameters were not significantly affected by pesticide application, the microbial community structure experienced an undesirable impact as compared to control devoid of pesticide treatment. Examination of DGGE banding patterns through cluster analysis revealed that microbial community structure of pesticide-treated soils had only 70% resemblance to control rhizospheric soil even at 45 days post application. Drastic changes in the metabolic profiles of pesticide-treated soils were also detected in terms of substrate utilization, rhizospheric diversity, and evenness. It is noteworthy that the effects exacerbated by biopesticide were comparable to that of synthetic pesticides, thus emphasizing the significance of ecotoxicological assessments before tagging biopesticides as 'safe alternatives.' [ABSTRACT FROM AUTHOR]

The problem of ticks and tick borne diseases is a global threat and growing reports of resistance to commonly used insecticides further aggravated the condition and demands for country specific resistance monitoring tools and possible solutions of the problem. Establishment of standard reference is prerequisite for development of monitoring tools. For studying possible role of different mechanisms involved in development of resistance in Rhipicephalus ( Boophilus ) microplus population and to develop newer drug to manage the problem of resistance, a deltamethrin exposed and selected tick colony, referred to as IVRI-IV, was characterized using reference susceptible IVRI-I tick line as control. The RF values of IVRI-IV ticks against deltamethrin, cypermethrin and diazinon were determined as 194.0, 26.6, 2.86, respectively, against adults. The esterase enzyme ratios of 2.60 and 5.83 was observed using α-naphthyl and β-naphthyl acetate while glutathione S–transferase (GST) ratio was 3.77. Comparative analysis of IVRI-I and IVRI-IV carboxylesterase gene sequences revealed 13 synonymous and 5 non synonymous mutations, reported for the first time. The C190A mutation in the domain II S4-5 linker region of sodium channel gene leading to leucine to isoleucine (L64I) amino acid substitution was also detected in the IVRI-IV population. In the present study, monitorable indicators for the maintenance of the reference IVRI-IV colony, the first established deltamethrin and cypermethrin resistant tick line of India, were identified. [ABSTRACT FROM AUTHOR]

Amsacta albistriga is one of the important pests of oilseed crops in India. This pest has developed high resistance to organophosphate (OP) insecticide in field. Therefore, cypermethrin insecticide was used as an alternative for this pest. After 20 generations of selection with cypermethrin, the LD 50 value for A. albistriga was increased by 21.5-folds. The synergism ratio of piperonyl butoxide (PBO) and triphenyl phosphate (TPP) was increased by 10- and 9.6-fold in resistant strains and comparatively, 3.9 and 4.2-fold in susceptible strains. Detoxification enzyme analysis and native PAGE electrophoresis of esterase isoenzyme further revealed that esterase and mixed function oxidase may be involved in cypermethrin resistance in CypRes strain. In addition to enzyme analysis overexpression of CYP4M44, CYP9A77 and CYP6B47 (ortholog) can confer metabolic resistance in the CypRes strain. These data provide a foundation for further study of cypermethrin resistance mechanism observed in A. albistriga . [ABSTRACT FROM AUTHOR]

The multi host tick, Hyalomma anatolicum, is the commonest Hyalomma species in India and cattle serves as the main host of this species. A study to evaluate the acaricide resistance of H. anatolicum to deltamethrin, cypermethrin and diazinon was conducted in 20 areas located in three agro climatic regions known to have abundance of the species. Results obtained by the 'larval packet test' (LPT) showed a low grade resistance (level-I, RF <5) in the tick species to both deltamethrin and cypermethrin in 10 areas and higher grade resistance (level-II, RF <25) to deltamethrin in one area, where intensive use of synthetic pyrethroids are practiced for tick control. Low grade resistance to diazinon (level I) was recorded in six areas where organophosphates compounds are extensively used for agricultural practices allowing increased exposure of the moulting instars of the ticks to these chemicals. Biochemical analysis of the samples suggested involvement of esterase and alterations of acetylcholinesterase in the resistance mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: A cross sectional study was conducted to assess the prevalence of synthetic pyrethroids (SP) resistance in Rhipicephalus (Boophilus) microplus in India. Twenty-seven areas located in six agro-climatic regions were selected for the collection of engorged ticks using two stage stratified sampling procedure. Adult immersion test (AIT) and larval packet test (LPT) were optimized using laboratory reared susceptible line of R.(B.) microplus (IVRI-I) for determination of 95% lethal concentration (LC95) of deltamethrin (29.6ppm in AIT and 35.5ppm in LPT) and cypermethrin (349.1ppm in AIT and 350.7ppm in LPT). The AIT with a discriminating dose (2× LC95) was used to detect deltamethrin and cypermethrin resistance in the field isolates of R.(B.) microplus. On the basis of the data generated on three variables viz., mortality, egg masses and reproductive index, the resistance level was categorized as I, II, III and IV. The overall prevalence of SP-resistant R.(B.) microplus among the sampled farms was 66.6% (18/27). Out of these 18 areas, resistance to deltamethrin at level I was detected in 08 areas (resistance factor=2.0–4.9), at level II in 09 areas (RF=5.2–11.8), at level III in 01 area (RF=34.9) and at level IV in 01 area (RF=95.7). The resistance to cypermethrin was detected in 16 areas and level of resistance was detected at level I in 10 areas (RF=2.06–4.64) and at level II in 06 areas (RF=5.13–9.88). The middle-gangetic and trans-gangetic plains revealed higher density of resistant ticks where intensive cross bred cattle population are reared and the SP compounds are commonly used. The data generated on acaricide resistant status in ticks will help in formulating tick control strategy for the country. [Copyright &y& Elsevier]

Despite the continuous use of synthetic insecticides during the last two decades, the tea mosquito bug Helopeltis theivora Waterhouse still exists as the most destructive pest of tea in North East India. The susceptibility levels of the female sucking bug collected from conventional (synthetic insecticide treated: Terai and Dooars plain regions) and organic (synthetic insecticide untreated: low-altitude Darjeeling region) tea plantations of the northern part of West Bengal to two synthetic insecticides, quinalphos and cypermethrin, and the activity of three principal detoxifying enzymes were assayed. Compared with the susceptible Darjeeling population, the Terai and Dooars populations showed a resistance factor at the lethal concentrations for 50% level ranging from 547- to 2680.87-fold and from 3810- to 7480-fold for quinalphos and cypermethrin, respectively. General esterases (GEs), glutathione S-transferases (GSTs) and cytochrome P450-mediated mono-oxygenases (CYPs) also showed an increased activity in the Terai and Dooars populations compared with those from Darjeeling. Defence enzyme activity was enhanced by 15.4- and 17.6-fold for GEs, 1.8- and 1.9-fold for GSTs and 2.1- and 2.4-fold for CYPs in the synthetic insecticide-treated H. theivora populations when compared with the untreated Darjeeling populations. Electrophoretic analysis for GEs showed a higher level of expression for esterase I–VI isozymes in the Terai and Dooars populations when compared with that in the Darjeeling populations. This study reveals a reduced efficacy of quinalphos and cypermethrin against field populations of H. theivora, possibly due to enhanced activities of GEs, GSTs and CYPs. The findings may be used in developing integrated resistance management strategies that can help in the effective control of this major tea pest. [ABSTRACT FROM AUTHOR]

Samples of okra and brinjal fruits, collected from non-integrated pest management (Non-IPM) and IPM fields in village Raispur, Ghaziabad District (U.P.), were analyzed for pesticide residues. The residues of chlorpyrifos in soil were 4.219 and 1.135 μg/g at harvest time in non-IPM and IPM fields of summer okra crop from initial value of 0.407 μg/g before sowing, while in brinjal crop, it was not detected in soils of any trials. During first year of study, the residues of chlorpyrifos and cypermethrin in okra fruit were observed to be 5.75 and 0.625 μg/g, respectively, for non-IPM fields; and 0.104 μg/g of chlorpyrifos for IPM trials. The pesticide residues were found to be 0.77, 1.39, 0.4 and 0.32 μg/g for cypermethrin, chlorpyrifos, monocrotophos and dimethoate, respectively, for non-IPM okra fruits in second year. For brinjal fruit, residues of cypermethrin and imidacloprid were not detected in IPM trials while it was found to be 0.28 and 0.78 μg/g for cypermethrin and chlorpyrifos respectively, for non-IPM trials. [ABSTRACT FROM AUTHOR]

Following foliar applications of combination formulation (cypermethrin 5% + acephate 45% DF) at 850 and 1,700 g ha−1, resulting in active application of acephate at 382.5 and 765 g a.i. ha−1 whereas active application of cypermethrin at 42.5 and 85 g a.i. ha−1, the average initial deposits of acephate on cotton leaves were found to be 13.45 and 27.73 mg kg−1, at single and double the doses of application, respectively. Residues of acephate declined below detectable level of 0.02 mg kg−1 after 15 days of applications at application rates with t ½ values of 1.56 and 0.68 days, respectively. Similarly, the average initial deposits of cypermethrin were found to be 22.31 and 32.45 mg kg−1, respectively. Cypermethrin residues reached below its detectable level of 0.02 mg kg−1 after 21 days of its application at both the dosages of application. The half-life values for cypermethrin were observed to be 0.71 and 0.69 days, corresponding to single and double the dose of application, respectively. Interestingly, none of the samples of cottonseed, lint and soil showed presence of acephate or cypermethrin at the detection limit of 0.02 mg kg−1 at first pick of the harvest time of the crop. [ABSTRACT FROM AUTHOR]

The abuse of acaricides for control of Rhipicephalus sanguineus sensu lato ticks led to a strong selection pressure for acaricide resistance. Data on acaricide resistance in R. sanguineus s.l. populations from India is meager though veterinarians frequently report treatment failures. The present study was aimed to characterize the level of resistance in R. sanguineus s.l. against most commonly used drugs, cypermethrin and ivermectin in Andhra Pradesh, south India. Fourteen adult female tick populations were collected from naturally infested dogs at veterinary clinics, residence and stray dog in nine state municipal corporations/municipalities. Information on the history of dog treatment with acaricides was obtained by interviewing dog owners. The larval packet test (LPT) and larval immersion test (LIT) were used on the larvae of ticks to test for resistance to cypermethrin and ivermectin, respectively. Mortality data of each tick population was analyzed by probit analysis. Corresponding to the most susceptible population, thirteen (92.6%) and six (42.9%) tick populations were regarded as resistant to cypermethrin and ivermectin, respectively. The phenotypic level of cypermethrin (resistance ratios at LC50% varied from 1.55 to 13.29) and ivermectin (resistance ratios at LC50% ranged from 1.16 to 4.79) resistance varied distinctly between the populations. Additionally, all the populations were tested using PCR to demonstrate the frequency of the point mutation in sodium channel gene that corresponds with resistance of R. sanguineus s.l. to cypermethrin. A nucleotide substitution (T2134C) on domain III segment VI of the sodium channel gene was noticed in phenotypically resistant tick populations on DNA sequencing. Ivermectin resistance in the brown dog ticks is reported for the first time from India., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

The article presents a study which determines the residues of synthetic pyrethroid insecticides, including fenvaterate, cypermethrin, and deltamemethrin, on tomato fruits on sub-tropical conditions in Punjab, India. The study used electron-capture detector, rotary vacuum evaporator, and quantitative research. Results show that synthetic pyrethroid's low initial deposit on tomato fruits has been ascribed to their application at low dosages.

Studies on estimation of yield losses of groundnut due to major insect pests revealed that the highest pod (1367 kg/ha) and fodder (2947 kg/ha) yield as well as CBR of 1: 6.51 was obtained in the plot sprayed with dimethoate 0.03%, chlorpyriphos 0.05 %, profenophos 0.05 % and profenophos 40 % + cypermethrin 4 % % 0.044% at 15 days interval starting from 20 days after sowing till harvest of the crop. The avoidable yield loss due to major insect pests of groundnut was recorded to the tune of 48.57 % in pod and 42.11 % in fodder in untreated control plot. The data on yield in protected plots revealed that 94.45 % additional yield in pod and 72.74 % additional yield in fodder could be realized over unprotected plots. [ABSTRACT FROM AUTHOR]

Background: Long-lasting insecticidal nets (LLINs) are the primary method of malaria prevention. However, the widespread resistance to pyrethroids among major malaria vector species represents a significant threat to the continued efficacy of pyrethroid LLIN. Piperonyl butoxide (PBO) is a synergist that inhibits the activity of metabolic enzymes of the cytochrome P450 family known to detoxify insecticides including pyrethroids. Synergist LLIN incorporating PBO and a pyrethroid may provide improved control compared to pyrethroid-only LLIN. Methods: The efficacy of VEERALIN® LN (VKA polymers Pvt Ltd, India), an alpha-cypermethrin PBO synergist net was evaluated in experimental huts in M'bé, central Côte d'Ivoire against wild pyrethroid resistant Anopheles gambiae s.s. Comparison was made with a standard alpha-cypermethrin-treated net (MAGNet® LN, VKA polymers Pvt Ltd, India). Nets were tested unwashed and after 20 standardized washes. Results: VEERALIN® LN demonstrated improved efficacy compared to MAGNet® LN against wild free-flying pyrethroid-resistant An. gambiae s.s. Before washing, VEERALIN® LN produced mortality of An. gambiae s.s. (51%) significantly higher than the standard pyrethroid-only net (29%) (P < 0.0001). Although there was a significant reduction in mortality with both LLINs after 20 washes, VEERALIN® LN remained superior in efficacy to MAGNet® LN (38 vs 17%) (P < 0.0001). Blood-feeding was significantly inhibited with both types of insecticide-treated nets relative to the untreated control net (P < 0.0001). Unwashed VEERALIN® LN induced significantly higher blood-feeding inhibition of An. gambiae s.s. (62.6%) compared to MAGNet® LN (35.4%) (P < 0.001). The difference persisted after washing, as there was no indication that either LLIN lost protection against biting or blood-feeding. The level of personal protection derived from the use of VEERALIN® LN was high (87%) compared to MAGNet® LN (66–69%) whether unwashed or washed. The AI content of VEERALIN® LN after 20 washes decreased from 6.75 to 6.03 g/kg for alpha-cypermethrin and from 2.95 to 2.64 g/kg for PBO, corresponding to an overall retention of 89% for each compound. Conclusions: The addition of the synergist PBO to pyrethroid net greatly improved protection and control of pyrethroid-resistant An. gambiae s.s. The pyrethroid-PBO VEERALIN® LN has the potential to reduce transmission in areas compromised by pyrethroid resistance. [ABSTRACT FROM AUTHOR]

A study to evaluate cypermethrin resistance in Rhipicephalus (Boophilus) microplus and Hyalomma anatolicum collected from Muktsar and Mansa districts of Punjab state, India, was conducted by using adult immersion test (AIT). The regression graphs of probit mortality of ticks plotted against log values of concentrations of cypermethrin was utilized for the determination of slope of mortality, lethal concentration for 50% (LC50), and the resistance factor (RF). On the basis of the data generated on variables (mortality, egg mass weight, reproductive index, and percentage inhibition of oviposition), the resistance levels were categorized. Resistance to cypermethrin was categorized as level II and I in R. (B.) microplus collected from Muktsar and Mansa districts, respectively, whereas, H. anatolicum from both locations showed a susceptible status. The RF values of Muktsar and Mansa field samples of engorged R. (B.) microplus (5.48 and 2.18, respectively) were much higher as those of engorged H. anatolicum (1.12 and 0.82, respectively) indicating a lower level and slower rate of development of cypermethrin resistance in multi-host ticks. The data generated in the current study might be of immense help in formulating suitable control measures against ticks and tick-borne diseases of animals., (Copyright © 2013 Elsevier GmbH. All rights reserved.)