Search

A convenient synthetic route of deuterium-labeled D5-cyhalothrin, D5-fenpropathrin, and D5-fenvalerate is described with 98.7%, 98.5%, and 98.3% isotopic enrichment and high chemical purities using D6-phenol as labeled starting material. These structures and isotope-abundance were confirmed by 1H NMR and mass spectrometry. The prepared D5-cyhalothrin, D5-fenpropathrin, and D5- fenvalerate can be used as a standard internal reagent for the determination of residual pyrethroids of food and environment.

BACKGROUND The seasonal long-distance migration of pests amongst different seasonal habitats may encounter different degrees of insecticides' selection pressure, but the knowledge on the evolution of resistance and the underlying mechanisms remains little. Here, we show that the development of resistance of the oriental armyworm Mythimna separata (Walker), a notorious agricultural pest that migrates between northern and northeast China seasonally across the Bohai Gulf, is influenced by seasonal migration. RESULTS There are two conspicuous migrations of M. separata, the northeastwards population in the second half of May and the returning population in the second half of August, between northern and northeast China per year, and the abundance values of migrants from April to October are significantly different. The resistance levels of seasonal migratory populations to λ-cyhalothrin vary in different months, and the resistance levels and estimated frequency of the resistance allele of the first northeastward population (second half of May, May.-2) in spring are significantly higher than those of the returning populations in autumn. Moreover, resistance decline was observed in migrating population Jul.-2, with the resistance levels in the F1 progeny higher than those in their F2 progeny. Synergism tests indicate that cytochrome P450 monooxygenases (P450s) play a major role in resistance. Enzymatic assays show that the P450 activity is significantly correlated with resistance levels in migratory populations, indicating that increased P450 activity is the main mechanism of resistance. The expression levels and correlation analysis of the relative expression of P450s with resistance levels show that 3 (i.e. CYP9A144, CYP9G40, and CYP6B79) out of 23 genes from CYP6 and CYP9 subfamilies are potentially involved in resistance to λ-cyhalothrin. CONCLUSION Our results show that the resistance of M. separata to λ-cyhalothrin is unstable and likely to be metabolically driven by enhanced P450 activity mediated by the overexpression of multiple P450 genes. Notably, the development of resistance is probably affected by seasonal migration. This article is protected by copyright. All rights reserved.

Insecticides are used widely to control insect pests affecting cowpea and their residues are often deposited in the soil. This may impact the physico-chemical characteristics of the soil and the plant health. This study was designed to investigate the growth response of cowpea treated with lambda-cyhalothrin and dimethoate and the insecticides influence on the physico-chemical characteristics of the soil. Three cowpea seeds were planted per polyethylene bag containing top soil, and later thinned to two plants. The insecticides were assayed singly or combined. The insecticides were applied at the pre-flowering (30th day), flowering (50th day) and at podding (70th day) stages of cowpea growth. The physico-chemical parameters of treated soils were assayed. Treated soils with lambdacyhalothrin and dimethoate and the control were slightly acidic with pH varying from 5.78 to 6.55. Soil organic matter and soil nutrients such as nitrogen, phosphorous, potassium and sodium had lowest values in untreated soil; they had highest values in soil treated with combined insecticides. Lambda-cyhalothrin and dimethoate treatments elicited diverse response from the cowpea plant. Generally, there were slight increase in the vegetative parameters, yield and pod dimensions of treated plants when compared with the control. These insecticides also increased the root nodules, root length and dry weight of cowpea at different concentrations. The combination of these insecticides had positive effect on cowpea without adverse influence on the yield and as well as the soil physicochemical properties.

The aim of the study was to perform a comparative evaluation of the toxic effects of selected botanical and synthetic insecticides on the subterranean termites, Macrotermes subhyalinus. Workers and soldiers of M. subhyalinus were exposed to various concentrations (0, 50, 100, 150 and 200 mg/ml) of the aqueous extracts of six plant materials; Anchomanes difformis (leaf, rhizome), Curcuma longa (rhizome), Tithonia diversifolia (leaf, root), and Zingiber officinale (rhizome) and termites’ mortality were monitored at 24, 48, 72 and 96 h post-exposure durations. Similarly, the termites were exposed to 0.001, 0.01, 0.1, and 1 % w/v of four synthetic insecticides; chlorpyrifos, dichlorvos, cypermethrin and cyhalothrin. All the plant materials and synthetic insecticides exhibited termiticidal activity even at the lowest concentration tested. For the plant materials, the LD50 values were highest in the groups treated with T. diversifolia (root) for most of the exposure durations while the LD50 values were lowest in A. difformis (rhizome) group at most of the exposure durations. For the synthetic pesticides, the LD50 values were highest in in the groups treated with dichlorvos for most of the exposure durations while the LD50 values were lowest in cypermethrin group at most of the exposure durations. These data suggest that Anchomanes rhizome has the highest termiticide activity among plant materials while cypermethrin was the most potent of the four synthetic insecticides. The results of the present study indicated that all the screened plant materials produce termiticide activity comparable to those of synthetic termiticides, and are therefore potential candidates for termiticide formulation for incorporation into integrated management of termites.

The present study was conducted with the aim of evaluating the effect of using three temperatures of 30, 40, and 50 °C and five exposure periods of 6, 12, 24, 48 and 96 hours/degree of temperature in reducing the residues of Lambda-cyhalothrin in water under laboratory conditions and measuring these residues using HPLC as well as Biological evaluation of these residues before and after thermal treatments. The HPLC readings of the residues of this pesticide showed that the highest general average of the degradation rate was at the concentration of 30 ppm / active substance (93.47%) and at the temperature at 30 °C (94.79%), while it was only for the exposure period. 48 hours significant effect (89.80%), and the percentage of deterioration in the effectiveness of the pesticide against adults of the insect T.confusum ranged between 96.72 and 99.22%, and the highest of these percentages was at a concentration of 10 ppm (99.22%) and at a temperature of 40 °C (98.33%). for the exposure periods 24 and 48 hours (98.29%). This may indicate the sensitivity of this pesticide to the temperatures used, which seemed to be high in its initial limit, while the highest rate of degradation was 89.08% at the 48-hour period, which differed significantly from The rest of the other averages, which reached 82.2, 85.26, 89.35 and 86.95% for exposure periods of 6, 12, 24 and 96 hours, respectively.

Vector-borne diseases are increasing exponentially, and the mosquito vectors contribute to the majority of it. Dengue fever is considered one of the foremost causes of causalities around the globe, which is primarily transmitted by Aedes aegypti. Control sequences of this vector species using chemical insecticides are now come to be insufficient due to the rapid resistance development in the aimed species. To avoid this, a newer concept of synergy has been introduced by combining two or more compounds with pesticidal capacity. In this study, a hexane extract of the plant Croton bonplandianum are separately combined with two pyrethroids, Lambda-cyhalothrin and Cypermethrin against the dengue fever vector, Aedes aegypti. Individual larvicidal capabilities and the synergistic effects of these compounds were inquired, and synergism was found to provide better larvicidal activity.

Aquatic organisms are often exposed briefly to high pesticide concentration. Survival time model was used to study risk of death in C. gariepinus and O. niloticus fingerlings exposed to 24 mg/L atrazine, 42 mg/l mancozeb, 1 mg/L chlorpyrifos and 0.75 µg/L lambda cyhalothrin for 15, 30, 45 and 60 minutes and continuously for 96 hours. Mortality, time-to-death, weight, length, and condition factor of the fingerlings were recorded. Results obtained showed tilapia was more susceptible than catfish to continuous exposure but not pulse exposure. The survival probability of both species was similar when exposed for 15, 30 and 45 minutes (p > 0.05) but differed after 60 minutes (p p > 0.05). Survival probability of tilapia exposed to chlorpyrifos for 15, 30, 45 and 60 minutes was similar (p > 0.05) and was not influenced by pulse length. Pesticide hazard and risk of death decreased as fish size (weight, length, and condition factor) increased. Pulse toxicity assessment using survival models could make pesticides exposure assessment more realistic by studying factors that can influence the toxicity of pesticides.

Barrier treatment of vegetation using lambda-cyhalothrin has been shown to be effective at reducing adult mosquito populations in the US. However, recent investigations have indicated that standard residual adulticide barrier treatments may be enhanced when combined with an insect growth regulator targeting immature stages that could be transferred to immature habitat by adults contacting treated surfaces. We conducted field trials at residential sites in a subtropical urban environment in north central Florida treating blocks of vegetation with residual sprays of lambda-cyhalothrin (Demand® CS) and pyriproxyfen (Archer®) alone and in combination treatments to determine their efficacy against peridomestic mosquitoes. The combined treatment resulted in consistent approximately 100% reduction in Aedes mosquito eggs for 16 wk post-treatment compared to not significantly lower but more variable reductions at alone treatment sites.

Glutathione S-transferase genes in the epsilon group were reported to function in insecticide resistance. SlGSTE12 was validated to be overexpressed in pyrethroid- and organophosphate-resistant populations of Spodoptera litura compared to a susceptible population. A functional study of heterologously expressed SlGSTE12 showed that Km and Vmax for 1-chloro-2,4-dinitrobenzene (CDNB) conjugating activity were 0.70 ± 0.18 mmol L-1 and 90.6 ± 9.4 nmol mg-1 min-1, respectively. β-Cypermethrin and cyhalothrin showed much weaker inhibition of SlGSTE12 activity to CDNB conjugation than fenvalerate, chlorpyrifos, and phoxim. Ultrahigh-performance liquid chromatography analysis showed that SlGSTE12 had significant metabolism activity to fenvalerate and phoxim both in vitro and in Escherichia coli, especially to chlorpyrifos, and slight metabolism activity toward cyhalothrin only in vitro. Silencing of SlGSTE12 by RNAi increased the mortality to fenvalerate, cyhalothrin, and chlorpyrifos significantly. SlGSTE12 also had a significant antioxidant ability against cumene hydroperoxide. Our study suggested that SlGSTE12 could metabolize phoxim, fenvalerate, cyhalothrin, and especially chlorpyrifos. SlGSTE12 might also participate in pyrethroid and organophosphate resistance by antioxidant activity.

Some crop growers hold the view that application of pesticides at higher than the manufacturer's recommended doses results in better pest control and crop productivity. The veracity of this perception was evaluated in field experiments at the experimental field of Federal University Wukari. A recommended insecticide and acaricide; ® Magicforce (Lambda-cyhalothrin 15g/L + Dimethoate 300 g/L) was evaluated against insect pests of watermelon (Citrullus lanatus Thunb.) and other associated beneficial arthropods. The experiments were laid in a Randomized Complete Block Design with five treatments (control inclusive). Data collected includes arthropod (pest and beneficial) densities, crop growth, and number of fruits at the early-fruiting stage which were analyzed using variance analysis after appropriate transformations. Student's t-test was used to compare early- and lateseason's variables while correlation and regression analyses were used to determine relationships between key variables. Results showed that plots treated with double the highest manufacturer's recommended dose of ® Magicforce (cost implication of ₦ 144,000) had lower pest (leaf beetle species and Bactrocera cucurbitae) and beneficial arthropod (predatory ants, spiders and Apis mellifera) densities than those treated with the lowest (cost – ₦ 48,000) and highest (cost – ₦ 72,000) recommended doses. Their plant growth (vine length and number of leaves) and fruit production were however comparatively lower though largely statistically comparable. The ® relationship between the quantity of Magicforce applied and number of fruits produced were though positive, 2 2 only moderate and insignificant in both early- (r = 0.665, R = 44.3%, p = 0.220) and late- (r = 0.659, R = 43.4%, p = 0.227) crops. The results revealed that the application of double the manufacturer's recommended dose of ® Magicforce (with its comparatively higher cost implication of 100 – 200%) suppressed growth of watermelon by 1.96 – 6.20%, and impeded fruit production by 9.14 – 13.30%. While there is need to verify the mechanism of this key finding, the need to source for genuine pesticides and follow manufacturer's recommended doses a re highlighted. Keywords: Arthropods, Insect pests, Organophosphate, Pesticide over-dose, Pyrethroid, Watermelon

Lambda-cyhalothrin (LCT) is a type II pyrethroid insecticide, which is widely used to control a large variety of agricultural pests throughout the world as well as in Algeria. The aim of this study was to investigate the effects of LCT exposure on body weight, hematological and blood biochemical parameters and to evaluate histopathological changes in some organs. Twelve (12) healthy local rabbits with a mean body weight of 1.8 kg were divided into three groups of four each: First group was kept as control (CTRL), second group (LCT 10) and third group (LCT 20) were given oral LCT at 10 and 20 mg/kg b.w, respectively three times a week for 25 days. The results showed no significant difference in mean body weight between groups. Blood analysis revealed no significant variation in hemogram between LCT-treated groups and control group. Serum biochemical analysis revealed a significant increase (P˂0.05) in total cholesterol content and glucose in LCT10 and LCT20, respectively. Total protein increased significantly (P˂0.0001) in LCT 20 group. While a very high increase (P˂0.0001) in the activity of asparatate aminotranferase (AST) was recorded in both treated groups, no change was observed in the activity of alanine aminotransferase (ALT). LCT treatment exhibited severe histopathological changes in liver, kidney, lung and brain. It is concluded from the study that LCT produced serious toxic pathological alterations and metabolic dysfunctions in rabbits.

Background: Insecticides such as lambda-cyhalothrin(LCT), dibenzalacetone (DBA) and heptanone HD are teratogenic substances. Skeleton is one of the organs sensitive to teratogens during the period of organogenesis. Material and methods:This study was conducted on fifty adult female albino mice, divided randomly into four groups: Group I (control group, n= 5 received corn oil orally in adose of 10 mg /kg body weight), group II (LCT group, n=10 received LCT (nano 8%)10, 20 mg /kg body weight for each subgroup), group III (DBA group, n=20, received DBA (main) 10, 20 mg /kg body weight and DBA (nano 8%)) 10,20mg /kg body weight for each subgroup) and group IV (HD group, n=15, received HD (main) 10 mg /kg body weight and HD (nano 8%)) 10,50mg /kg body weight for each subgroup),The calculated treatment dissolved in 1 ml of corn oil by orogastric tube was given to the pregnant mice during the first week of pregnancy (1st, 3rd and 5th day).The delivered live and dead pups were examined externally, then double stained and prepared for skeletal examination by dissecting microscope. Results: All experimental groups showed various anomalies that can be categorized as the following: 1) presence of dead pups and resorption sites 2) macroscopic anomalies in the form of anencephaly, extended forelimb, cranioshisis, macroglossia, lowset ears, lage eye bulge, half body, amelia, internal rotation of forelimb and encephalocele. 3) skeletal anomalies by double staining of fetal skeleton showed incomplete ossification of nasal and interparietal bones, open arch of atlas, incomplete ossification of vertebrae, supernumerary ribs, wavy ribs, incomplete ossification of ribs and sternebrae, incomplete ossification of sternum, incomplete ossification of 5th metacarpal and terminal phalangal bones and incomplete ossification of tarsal , and phalangal bones. Conclusion: Lambda-cyhalothrin, dibenzalacetone and derivatives of heptanone result in numbers of congenital gross and skeletal abnormalities that indicate their teratogenic effect. KEY WORDS: Lambada, Congenital, Skeletal, Dibenzalacetone, Heptanone, Teratogenic.

For farmers, pesticides and insecticides are both allies and enemies. The long-term risks they generate can have significant adverse effects on farmers. In order to avoid pests and insects, the application of these chemicals in the field is also important. In the recent years, serious attention has been paid to the harmful effects of pesticides on the environment and human health by the public authorities. It is necessary for farmers to wear protective equipment in this condition to avoid the inhalation as well as absorption of these chemicals (by skin). These chemicals cause have side effects ranging from nausea, headache, temporary blindness to adverse health conditions like permanent blindness, respiratory disorder, nervous system problem, and cancer. A survey was conducted in the western region of India where 30 chemicals were auditioned among which malathione, pyrethroids and cyhalothrin got selected for further progress. Upon docking these chemicals with neutrophil elastase, cholestrerly ester transfer, G alpha, β-arrestin proteins. We found that these chemicals showed affinity with a high binding interaction towards the aromatic amino acids residues that can form H- bonds with a higher binding interaction. Therefore, from our in-silico findings we hypothesize that peptide matrix will be a good candidate for preparing blended masks to entrap the hazardous chemicals from the sprays.

Wild-type Hyalella azteca are highly sensitive to pyrethroid insecticides and typically do not survive exposure; however, pyrethroid bioaccumulation by insecticide-resistant H. azteca is an important potential risk factor for the transfer of pyrethroids to higher trophic species in aquatic systems. In the current study, four populations of pyrethroid-resistant H. azteca with corresponding sediment samples were sampled throughout the year, and nine-current use pyrethroids (tefluthrin, fenpropathrin, bifenthrin, cyhalothrin, permethrin, cyfluthrin, cypermethrin, esfenvalerate and deltamethrin) were measured. Bifenthrin was detected in every pyrethroid-resistant H. azteca tissue sample, up to 813 ng/g lipid, while cyhalothrin and permethrin were detected in fewer (18 and 28%, respectively) samples. Concurrent sampling of the sediment showed total pyrethroid concentrations exceeding toxic unit thresholds for non-resistant H. azteca survival, and confirmed the ubiquitous presence of bifenthrin at each site and sampling event. Bifenthrin concentrations in H. azteca tended to be higher in samples collected in winter months, and seasonal factors, such as temperature and rainfall, may have contributed to the noted differences in bioaccumulation. Finally, the bifenthrin and permethrin biota-sediment accumulation factors (BSAF) for pyrethroid-resistant H. azteca were similar to the BSAF values for less sensitive invertebrates, and therefore the development of resistance may enable an additional pathway for trophic transfer of pyrethroids in species that would otherwise be too sensitive to survive the exposure.

Laboratory studies were undertaken to assess the initial and persistence of lambada –Cyhalothrin insecticide on some porous and some non-porous surfaces. Formulation of insecticide was applied to polyethelyne and cement surfaces which are materials commonly used for grain storage facilities (packages) and in the construction of silos or storage. Lambada –Cyhalothrin insecticide was applied at concentrations 15.7, 7.8, 3.93, 1.9, 0.949 to 0.479g/m2 to test surfaces to determine Lc 95 to study their persistence against Rhyzopertha dominica and Callosobruchus maculates adults. Insects were exposed on treated surfaces Initial and residual efficacy was determined after 24 hrs. of insects contact with 7, 14, 30, 60, 90 , 120, 150, 180days of exposure deposits on each surface. Results indicated that; mortality rates were positively correlated with the concentration and negatively correlated with the time of application. Results indicated that: -Polyethylene was the most persistent surface which gave 100% mortality up to 6 months in Callosobruchus maculates and up to 5 months in Rhyzopertha dominica at the highest concentration in both tested insects. - In cement surface lambada cyhalothrin deteriorated very rapidly starting from the first month on both tested insects.

The prevention of vector-borne disease to protect the health and readiness of United States forces in the field continues to be a high priority for the US Department of Defense. Previous studies have demonstrated that the risk of human contact with disease-vector mosquitoes and other biting flies can be reduced by applying an insecticide to perimeters of military materials such as camouflage netting or HESCO blast protection wall geotextile already in place around troops in the field. In this study we investigated whether residual pesticide efficacy will persist in the presence of earth fill that is required for operational use of HESCOs, using a warm temperate field site in north Florida. Results from laboratory bioassays measuring mosquito mortality and field collections of natural mosquito populations indicated superior efficacy and greater longevity of pesticide treated geotextile exposed to soil fill. These findings not only support immediate implementation of this technique in US military field scenarios, but also provide evidence that HESCO technology currently used in natural disaster flood control could be leveraged to protect civilian personnel from emerging floodwater mosquitoes.

Presented study focused on the incidence of pesticides: malathion, chlorpyrifos and λ-cyhalothrin and heavy metal, arsenic in the rice samples collected from the three main rice growing areas. 30 samples of brown Super Kernel Basmati rice and Super Basmati rice varieties, irrigated through tube well irrigation were selected. Highly sensitive and selective method of High Performance Liquid Chromatography was used for determination of pesticides. Results of analysis showed the presence of malathion in one sample in concentration of 18.26 mg/kg, chlorpyrifos in two samples in concentration of 3.3 mg/kg and 1.45 mg/kg respectively and λ-cyhalothrin in one sample in concentration of 1.848 mg/kg. Amount of pesticides detected in these samples were exceeding their maximum residual limits thus showed their strong potential to pose significant health risk. The presence of arsenic in rice was determined by Atomic Absorption Spectrophotometer and it was detected in 12 samples out of 30 in range of 0.04-0.28ppm. The detected arsenic concentration of arsenic in all samples was within the permissible limits set by WHO/FAO.

To study the bio-efficacy of selected insecticides against earhead caterpillars in finger millet (variety KMR-204) under field conditions an experiment was conducted at Zonal Agricultural Research Station Vishweshwaraiah Canal, Farm, Mandya, during kharif 2018 and 2019, University of Agricultural Sciences, Bangalore. The results revealed that, two sprays at dough stage of the crop, all the insecticides viz., thiodicarb 76 WP (1.0 g L-1), acephate 75 SP (1.5 g L-1), profenphos 50 EC (2.0 mL L-1), quinalphos 25 EC (2.0 mL L-1), lambda cyhalothrin 5 EC (0.6 mL L-1), novuluron 10 EC (1.5 mL L-1), fenvelarate 0.4D (25 kg ha-1), chlorpyriphos 1.5D (25 kg ha-1) and chlorpyriphos 20 EC (2.0 mL L-1) were found to be effective in reducing different species of earhead caterpillars viz., Archips micaceana, Somena scintillans, Cryptoblabes angustipennella, Nola analis, Cydia sp., Helicoverpa armigera, Pyrausta phoenicealis, Corcyra cephalonica, Stathmopoda sp. and Spodoptera frugiperda, Eublemma sp., Conogethes punctiferalis, Euproctis similis, Mythimna separate and Ataboruza sp., over untreated control. However, thiodicarb 75 WP @ 1.0 g L-1 and lambda cyhalothrin 5 EC at 0.6 mL L-1 were found to be more effective in reducing the mean larval population and registered higher percentage of recovery with least larval population compared to rest of the insecticides.

The present investigation was carried out to study the bio-efficacy of insecticides against thrips infesting bitter gourd during rabi-summer season of 2017-18 at Centre of Excellence for Mango, College of Agriculture, Dapoli, Dist. Ratnagiri (M.S). There were six insecticides tested against thrips infesting bitter gourd. The results regarding overall mean of three sprays against thrips infesting bitter gourd revealed that the treatment chlorantraniliprole 18.5 SC @ 0.005 per cent was the best treatment which recorded minimum (2.41) population of thrips and was at par with malathion 50 EC @ 0.05 per cent (2.84) and spinosad 45 SC @ 0.014 per cent (3.05). The next effective treatment was emamectin benzoate 5 SG @ 0.002 (3.53) which was at par with treatments azadirachtin 1 EC @ 0.003 per cent (3.65) and lambda cyhalothrin 5 EC @ 0.0025 per cent (3.75). All the treatments were significantly superior over untreated control. The maximum (6.78) thrips population was observed in the untreated control.

This study was designed to assess the ameliorative effects of Spirulina platensis (SP) and Ulva sp. (US), as feed additives into a fish commercial feed, for reducing pesticide lambda cyhalothrin-residues in water and fish muscles. In the present experiment, the concentration tested was 2.325 μg/l as 1/10 of the determined LC50 - 96 hours was used for 28 days. The experimental design represents 6 groups: group 1 was control (cont.), group 2 was treatment with lambda-cyhalothrin (LCT) and two algae species with two concentrations each (5% and 10% of diet + lambda-cyhalothrin) are the other four groups. After the experimental period, serum biochemical tests (Glucose, Total Protein, Albumin, Globulin, AST, ALT, Urea, Creatinine and lipid profile) were determined. All biochemical analysis showed significantly varied in-between treatment except urea levels, while, these parameters were in normal rang in fish groups fed by both concentrations of SP and US. The residue levels of lambda-cyhalothrin in water samples were decrease in 10% concentration compared with 5% concentration in both algae. SP and US with two concentrations can efficiently remove lambda-cyhalothrin residues in fish muscles. Water quality (temperature, dissolved oxygen and pH) were no significant differences between all treatments from the beginning till the end of the experimental period. Conclusion: Spirulina platensis and Ulva sp have a big role in the reduction in the effect of lambda-cyhalothrin on fish and the improvement of water quality.

The responses of thrips to commonly used insecticides were studied in onion fields with the aim of detecting presence or absence of thrips resistance to insecticides in the Central Rift Valley of Ethiopia. Thrips populations were collected from area with heavy pesticide use history Meki and Melkassa and less use areas of Werer and Minjar. Collected adult thrips populations were exposed to various concentrations of λ -cyhalothrin, dimethoate, profenofos, diazinon and spinetoram treated vial and thrips mortality was assessed after 24 h. The percent mortality was significantly lower in Meki and Melkassa collected thrips populations than in Minjar and Werer populations to λ –cyhalothrin and diazinon at recommended field rate. On the other hand, differences were insignificant for the insecticides spinetoram and profenofos at recommended field rate. Of the five tested insecticides λ –cyhalothrin had higher resistance ratios to Meki (10.8-fold) and Melkassa (6.78- fold) collected thrips population, while resistance ratio was intermediate to diazinon and lowest to dimethoate and profenofos insecticides. Results of this study suggest that thrips affecting onion in Meki and Melkassa areas have developed resistance to λ –cyhalothrin and diazinon insecticides. Periodic assessment of efficacy of registered insecticides and deploying a pesticides resistance management strategy are useful for sustainable use of pesticides in integrated thrips management program.

Selected insecticides viz. Flubendiamide 39.35% SC, Indoxacarb 14.5% SC, Lambda cyhalothrin 5% EC, Novaluron 10% EC, Quinalphos 25% EC, Spirotetramat 120% SC+ Imidacloprid 120% SC Chlorantraniliprole 18.5% SC were evaluated for their effectiveness against tomato fruit borer by conducting field trial at PGI, MPKV, Rahuri during the year 2019. Three sprays of each insecticide were applied at the occurrence of the pest. The result revealed that lowest larval population (1.14 larvae/plant) of H. armigera was recorded in treatment of chlorantraniliprole 18.5% SC. Flubendiamide 39.35% SC (1.51 larvae/plant) was the next promising treatment followed by indoxacarb 14.5% SC exhibiting 1.70 larvae/plant. Treatments viz. spirotetramat 120% SC + imidacloprid 120% SC, lambda cyhalothrin 5% EC, quinalphos 25% EC found to be moderately effective against H. armigera and recorded larval population ranging from 1.99 to 2.27 larvae/plant H. armigera. Novaluron 10% EC was least effective, with maximum (2.42 larvae/plant) population of H. armigera.

The field investigations were carried out to evaluate the efficacy of seven newer insecticide molecules viz., profenophos 50 EC@ 30 ml, indoxacarb 14.5 SC @ 8.5 ml, emamectin benzoate 5 SG@ 4 g, spinosad 45SC @ 4 ml, thiamethoxam 12.6 + lambdacyhalothrin 9.5@ 2.5 ml, chlorantraniliprole 18.5 SC 3 ml, and flubendiamide 49.35 SC @ 2.5 per 10 lit. of water respectively. The results revealed that all the insecticidal treatments were significantly effective against aphid over untreated control. Among that thimethoxam 12.6 + lambda cyhalothrin 9.5 ZC was most effective treatment. The next effective insecticides were profenophos 50 EC, emamectin benzoate 5 SG, indoxacarb 14.5 SC, chlorantraniliprole 18.5 SC, flubendiamide 39.35 SC and spinosad 45 SC.

Cabbage aphid, Brevicoryne brassicae (L.) is an important agricultural insect pest that attacks many vegetable crops all over the world. Herein, the study was conducted to evaluate the efficacy of five insecticides, acetameprid 20% SP (neonicotinoid), abamactin 1.8% EC (avermectin), indoxicarb 15% EC (oxadiazine), chlorpyrifos methyl 50%EC (organophosphate) and lambda cyhalothrin 5% EC (pyrethroid) against cabbage aphids Brevicoryne brassicae (L.) and its parasitoid Aphelinus sp. under laboratory conditions. Mortality percentages for both cabbage aphid and parasitoid were determined after 24, 48 and 72-h after treatment. Result revealed that acetamiprid was the greatest toxic insecticide against cabbage aphid followed by abamectin and indoxacarb after 24 and 48-h of treatment. Otherwise, lambda cyhalothrin followed by chlorpyrifos methyl was the lowest toxicity on cabbage aphid after 24 and 48-h from treatment. In contrast, toxicological results for parasitoid suggested that acetamiprid had less toxicity followed by abamectin and indoxacarb after 24 and 48-h of treatment. whereas, lambda cyhalothrin followed by chlorpyrifos methyl demonstrated great toxicity on the parasitoid after 24 and 48-h of treatment. In addition, safety factor for each treatment was determined, and results revealed that greater safety factor was recorded for acetamiprid, abamectin and indoxacarb than chlorpyrifos methyl and lambda cyhalothrin. Thus, these results suggest that acetamiprid can be included in the Integrated Pest Management (IPM) Program against cabbage aphid with safe side and minimum harmful effect on its parasitoid.

The codling moth, Cydia pomonella (L.), is a quarantine pest of global significance impacting pome fruits and walnuts. It has evolved resistance to many commonly used insecticides including λ-cyhalothrin. Glutathione S-transferases (GSTs) are multifunctional enzymes playing a crucial role in the detoxification of insecticides in insects. However, the role of specific GST gene in λ-cyhalothrin resistance in C. pomonella is unclear. In this study, we identified three sigma-class genes (CpGSTs1, CpGSTs2, and CpGSTs3). These genes were ubiquitously expressed at all developmental stages, and of these, the expression level of CpGSTs2 in the larval stage was significantly higher than in the egg, pupal, and adult stages. Moreover, CpGSTs2 was predominantly expressed in the fat body while lower levels in the cuticle. In addition to exposure of larvae to LD10 of λ-cyhalothrin elevating the expression level of CpGSTs2, mRNA levels of CpGSTs2 in a field population (ZW_R) from northeast China, which has developed moderate level resistance to λ-cyhalothrin, was significantly higher than that of susceptible strains. In vitro inhibition assays demonstrated that λ-cyhalothrin inhibited the conjugating activities of recombinant CpGSTs2, and metabolic assays indicated that λ-cyhalothrin could be depleted by recombinant CpGSTs2. These results bring evidence for the involvement of CpGSTs2 in C. pomonella in resistance to λ-cyhalothrin.

The susceptibility of Culex pipiens larvae collected from Al-Asher of Ramadan, Sharkia Governorate, to chlorpyrifos and lambda-cyhalothrin insecticides was investigated for 20 successive generations. For multiple generations, the instar larvae of field parent strain were exposed to LC30 of the previous generation to that insecticide. Total protein and lipids content as well as activities of detoxifying enzymes (i.e. acetylcholinesterase, non-specific esterases and glutathione-S-transferase) were determined in each generation. Bioassay tests showed that larval Cx. pipiens developed 144.31 and 761.85-fold resistance to chlorpyrifos and lambda-cyhalothrin, respectively, after 20 successive generations of selected pressure. Total protein content declined while total lipids increased gradually with proceeded the generations. In general, the activities of detoxifying enzymes increased gradually with raising generation numbers which indicate that the increased resistance is likely to be associated with the increased activity of target and metabolic enzyme systems.

Diplonychus rusticus (Heteroptera: Belostomatidae) is relatively a bigger sized tropical water insect serves as a main predator of mosquito larvae. In the present study, toxicity and effects of three different insecticides viz., temephos, lambda-cyhalothrin and cypermethrin was evaluated on D. rusticus. The results showed that the cypermethrin exhibited highest toxicity with lowest LC50 and LC90 values of 0.02 and 0.12 ppm on D. rusticus. Observations showed that the functional response greatly varied with all the three insecticides. The mean number of preys consumed at the density of 64 larvae was significantly different among the treatments. The mean longest handling time of 4.18 ± 0.34 and the mean lowest attack rate of 0.015 ± 0.008 were observed in lambda-cyhalothrin and cypermethrin treatments, respectively. The adult longevity of D. rusticus was found to be very less (42.33 ± 1.52 days) in cypermethrin treatments, whereas it was 113 ± 1.73 days and 120 ± 2.64 days in lambda-cyhalothrin and temephos insecticides, respectively at 0.01 concentration. The coupling behavior of the insect was noted to occur very rarely in all the three insecticide treatments. The total number of eggs layed was 16 eggs and 26 eggs in lambda-cyhalothrin and temephos treatments at 0.01 concentration, respectively. Furthermore, it was noted that there are no eggs were hatched (0%) from these egg clusters. These results indicate that the tested insecticides exhibited sub-lethal effects on the predatory insect D. rusticus.

The cabbage aphid, Brevicoryne brassicae (L.), is one of the major insect pests of cole crops in Iran. In most instances outbreaks are normally kept under control by application of insecticides. In this study, the sublethal effects (LC30) of three insecticides, acetamiprid, buprofezin, and thiamethoxam-lambda cyhalothrin, (TLC) were evaluated on the population growth rate of the progeny of insecticide-treated cabbage aphid adults. The age-stage, two-sex life table method was used to analyze the collected data. The results indicated that the insecticide applications affected the duration of the preadult period, their survival, reproduction, life span/longevity, and consequently, the population growth rate of the F1 generation. The indicators of the greatest sublethal effects were noted in the progeny of the TLC-treated adults. These included the lowest net reproductive rate (R0), intrinsic rate of increase (r), finite rate of increase (λ), and the longest mean generation time (T). The highest values of r, λ, R, and the lowest value of T occurred in the control group followed by, in order, the acetamiprid and buprofezin groups. These research findings will be useful in the development and implementation of future aphid management programs.

Toxicity of newer insecticides viz., chlorantraniliprole 18.5 SC, flubendiamide 20 WG, buprofezin 25 SC, lambda cyhalothrin 9.5 + thiamethoxam 12.6 ZC, lambda cyhalothrin 5 EC, azadirachtin 5 w/w, thiamethoxam 25 WG, thiachloprid 21.7 SC were tested against different larval stages of Chrysoperla spp. under laboratory conditions. The observations on percent mortality of 1st, 2nd and 3rd instar of C. spp. larvae were recorded after 24, 48 and 72 hrs of application. The results showed that lambda cyhalothrin + thiamethoxam was found toxic to all instars of Chrysopa larvae whereas azadirachtin was found safest insecticide against all instar of Chrysopa larvae at all treatment intervals. Considering ecofreindliness, it can be concluded that insecticides azadirachtin, buprofezin and flubendiamide were found most safer to all instars of C. spp. which can be taken successfully in the IPM programmes whereas, lambda cyhalothrin + thiamethoxam was found most harmful to all instars of larvae.

Possible causes of brown plant hopper resurgence were determined at the net-house of Entomology Division of Bangladesh Rice Research Institute (BRRI) during 2015. Causes of resurgence in the form of resurgence ratios were higher with acetamiprid, acephate, chlorpyrifos, cypermethrin, deltamethrin, fenvalerate, lambda cyhalothrin, thiamethoxam insecticides compared to imidacloprid, cartap, dinotefuran, isoprocarb /MIPC, phenthoate, pymetrozine when even applied at recommended dose. However, thiamethoxam, imidacloprid, isoprocarb / MIPC and cartap applied at sub-lethal dose produced higher resurgence ratio of BPH than others. Isoprocarb / MIPC, a commonly used recommended insecticide was found to have a higher resurgence ratio with the insecticide treatment at the egg stage (1.71) and combination of all stages (0.82). These insecticides influenced on the growth and reproductive physiology of rice brown planthopper and consequently resurgence ratio ranged increased. SAARC J. Agri., 18(1): 117-128 (2020)

The study was carried out on cotton variety Giza 86 during two following seasons in 2017 and 2019 at the experimental farms of the faculties of Agriculture, Saba Bacha and El-Chatby, Alexandria, Egypt. The obtained results indicated that the highest efficacy was gained by Novatrin/ Radiant® and Novatrin/ Super Mix, which decreased the incidence of Earias insulana (0.84 and 1.24 larvae /10 green bolls, in respect) and pectinophora gossypiella infestation and increased the cotton yield up to (57.8 Kent/ fed(. Furthermore, Novatrin/ Super Mix and Super Mix/Radiant® - achieved the lowest value of yield losses(9.6% and 10.1%, respectively) during the cotton season of 2017, in addition to the foliar treatments of Novatrin/ Super Mix/Radiant® and Super Mix/ Potasin-F/ Radiant® gave higher efficacy in reducing the level of the spiny bollworm infestation(0.53 and 0.65 larvae /10 green bolls, respectively) in 2019 season, while the application of Novatrin/ Super Mix/Radiant® and Novatrin/Potasin-F/Radiant®, increased the cotton yield (106.2% and 84.9%, in respect) resulting in decreasing yield losses during the 2019 cotton season, while the foliar application of Novatrin / Super Mix, increased cotton fiber length(34.21mm), while the application of lambda - cyhalothrin and Super Mix greatly increased fiber strength (50.36 and 50.16 gram/ tex, respectively), the highest increased value of fiber micronair reading was detected for the performed application of Super Mix / Radiant® (4.88 millitex)during the 2017 cotton season, while the application of Novatrin / Potasin-F / Radiant® increased fiber length (33.66 mm), Novatrin / Super Mix / Radiant® treatments also increased fiber strength (45.53 gram/ tex) and the value of elongation (5.60%), as well as, application of Novatrin / Potasin-F/ chloropyrifos increased value of fiber micronair reading (4.88 millitex) during the 2019 cotton season.

Field experiments were carried out at Al-Quaren village, Sharkia governorate during seasons 2016 and 2017 to evaluate the efficiency of three synthetic insecticides belonging to two groups, synthetic pyrethroid (lambda-cyhalothrin) and neonicotinoids (thiamethoxam and acetampride) towards the tomato whitefly, Bemisia tabaci on tomato crop. As for, estimation of certain pigments content of fresh tomato leaves (chlorophyll a, chlorophyll b and carotenoids) had been conducted. The experiments were verified on randomized complete block design (RCBD) with three treatments Viz., T1; thiamethoxam (Actara 25% WP, 0.58g/2.88L),T2; acetampride (Mospilan 20 % SP, 0.72g / 2.88L), T3; lambda-cyhalothrin (Cyhalothrin 5% EC, 1.44 Cm 3/2.88L) and control. All treatments were repeated three times. The results revealed that all treatments of whitefly populations dropped in appreciable levels during 2016 and 2017 seasons. Furthermore, the results showed that the treatment after spraying with lambda –cyhalothrin gave the highest reduction in whitefly populations followed by 86.61, 71.99 and 67.80%, respectively, within 14 days of post- treatment. Respecting the impact of B. tabaci infestation on tomato pigments, the results showed that there were highly significant differences in all the mean content of pigments (chlorophyll a, b and carotenoids) in intact tomato leaves compared with the infested tomato leaves. The mean contents of chlorophyll A, B and carotenoids in intact tomato leaves were 9.155±0.134, 2.355± 0.126 and 2.436± 0.053 mg/g fresh tomato leaves, respectively, while in infested tomato leaves were 8.427± 0.710, 2.053± 0.288 and 2.759± 0.274 mg/g fresh tomato leaves, respectively. In conclusion, it could be recommended using lambda-cyhalothrin besides thiamethoxam in combating the tomato whitefly, B. tabaci, in integrated pest management (IPM).

The objective of this study is to evaluate the antioxidant and hepatoprotective activity of aerial part and seeds of Coriandrum sativum plant against Lambda cyhalothrin insecticide. Male Wistar Albinos rats were randomly divided into control, LCT, CsA, CsS, CsS+LCT, CsA+LCT groups, after 90 days of treatments Biochemical, some oxidative stress parameters, and histopathology of liver tissue were evaluated. Total polyphenol content in aerial part and the seed extract estimated at 9.29 and 14.64 mg EAG / mg of extract and IC50 for an antioxidant activity equal to 19.38 and 22.62 mg/ml respectively. The obtained results revealed that rats received Lambda cyhalothrin insecticide showed a significant change in enzymes activity (AST, ALT, ALP and c-GT) and Glutathione (GSH) in liver. Meanwhile content of hepatic Malondialdehyde (MDA). Histopathology examination of liver revealed that Coriandrum sativum attenuate the incidence of liver lesions triggered by Lambda cyhalothrin intoxication. Therefore, the results of this study show that Coriandrum sativum can be proposed to protect the liver against Lambda cyhalothrin induced oxidative damage in rats, and the hepatoprotective effect might be correlated with its antioxidant and free radical scavenging effect. Keywords: hepatoprotective, antioxidant, Coriandrum sativum L., Lambda cyhalothrin, Oxidative stress.

This study was designed to evaluate the acute toxicity of acetamiprid (neonicotinoid) and lambda-cyhalothrin (pyrethroid), individually and mixtures (Act-LCh mixture and Acer 35 EC®, 15 g/L of acetamiprid and 20 g/L of lambda-cyhalothrin) in African catfish juveniles (3.35 ± 0.75 g). The tests were conducted in the laboratory under semi-static conditions according to OECD Guideline 203. Mixture toxicity effects as a function of lethal concentrations were assessed using the additive index (AI) method. Acetamiprid with 96 h-LC50 = 265.7 ppm can be considered to be nontoxic for this species. However, lambda-cyhalothrin was highly toxic to C. gariepinus with 96 h-LC50 = 0.00083 ppm. Acer 35 EC® was less toxic (96 h-LC50 = 0.21 ppm) than the Act-LCh mixture (96 h-LC50 = 0.043 ppm). Marked changes indicating nervous system damage were also recorded. An antagonistic effect was shown for lethal concentrations leading to 5 to 15% mortality in 96 hours (96 h-LC5-15) while an additive effect was obtained for the 96 h-LC20-50. The results indicate that ecological risk assessment of these molecules in aquatic environments should consider their contamination levels. Moreover, particular attention to behavior changes related to their neurotoxicity is recommended for additional monitoring of the negative effects of these insecticides.

An experiment was carried out to study the safety of some new insecticides namely chlorantraniliprole 18.5 SC, flubendiamide 20 WG, buprofezin 25 SC, lambda cyhalothrin 5 EC, thiamethoxam 25 WG, dinotefuran 20 SG, thiacloprid 21.7 SC and azadirachtin 5 % w/w on egg, larval and pupal stage of Trichogramma japonicum parasitizing UV irradiated and unirradiated Corcyra cephalonica eggs by evaluation of percent reduction in adult emergence of when treated after 1st, 3rd and 5th day of parasitisation which is during egg, larval and pupal stage of Trichogramma respectively. Lambda cyhalothrin adversely affected the emergence of T. japonicum during all the life stages of T. japonicum. However azadirachtin, buprofezin, chlorantraniliprole and flubendiamide least affected the per cent reduction in adult emergence than other insecticides. Thiamethoxam was found selective towards different life stages of T. Japonicum.

Field experiments were conducted during Kharif 2018-19 to evaluate the efficacy of different insecticides against major lepidopteran pests of castor revealed that all the treatments were found significantly superior over untreated control in reducing pest population. The results the newer insecticides were in general, superior over the untreated check in reducing the larval population. Among the tested treatments, efficacy of the treatments viz., chlorantraniliprole 18.5 SC and flubendiamide 480 SC were superior and followed by spinosad 45 SC and indoxacarb 15.80 EC which were found to be effective for all lepidopteran pests of castor. Considering the cost-effectiveness of various treatments, the maximum cost-benefit ratio (1:3.08) was registered in lambda cyhalothrin 2.5 EC with yield of 10.83 q / ha followed by flubendiamide 480 SC with C:B ratio of 1:3.06 and chlorantraniliprole 18.50 SC with C:B ratio of 1:3.05 as well yield of 13.10 q / ha and 13.8 q / ha, respectively.

Analysis of the glutathione S-transferase (GST) gene expression in an insecticide-resistant strain of Cydia pomonella using real-time quantitative polymerase chain reaction is a key step toward more mechanism studies that require suitable reference genes with stable expression. Here, nine commonly used reference genes were selected, and their expression stabilities were analyzed. Results showed that EF-1α was the most stable reference gene in all of the experimental sets. The combinations of EF-1α and 18S, EF-1α and RPL12, and EF-1α and GAPDH were sufficient for normalization of gene expression analysis accurately in developmental stages, tissues, and larvae exposed to sublethal dose of λ-cyhalothrin, respectively. Additionally, the suitability of particular reference genes was verified by analyzing the spatiotemporal and insecticide-induced expression profiles of CpGSTe3, CpGSTd3, and CpGSTd4, which were overexpressed in a λ-cyhalothrin-resistant population from northeast China. These genes were used to confer the practicability of reference genes chosen in this study.

Peanut pod borer caused by Etiella zinckenella is one of the important pests of peanut in Indonesia. The symptoms of E. zinckenella attack are blackened pods and rotten seeds, causing yield loss up to 90%. The research aim was to validate the efficacy of various control technology components of peanut pod borer pests. The research was conducted at the Natar (Lampung) experimental station from April to August 2014. The research was arranged using a complete randomized design (CRD) method, the treatment consisted of six control technology components, and treatment was repeated four times. The results showed that the more larvae found in the pods, the greater the damage of the pods are crushed by larvae. Application of lambda cyhalothrin insecticide (P6) starting at 35–70 days after planting (DAP) was not able to suppress larval populations of E. zinckenella so that damaged pods were also larger and not significantly different from without control (P0). Lamda sihalotrin insecticide application also harms the survival of natural enemies (predators and parasitoids). Lamda cyhalothrin insecticides can be combined with other control components such as soybean trap plants, thiametoxam and carbofuran and parasitoid of Trichogramma bactrae-bactrae to control of peanut pod borer. Application of Lecanicillium lecanii biopesticide was combined with chemical insecticides thiametoxam or carbofuran can suppress E. zinckenella larvae and yield loses, beside it can safety against the survival of predators the order Araneida and Coleoptera and parasitoid of Hymenoptera and Diptera. Biopesticides of L. lecanii were combined with tiametoxam or carbofuran insecticides can be recommended for control agents of peanut pod borer E. zinckenella .

Two field experiments were conducted in the Central Rift Valley of Ethiopia in the hot and cool dry seasons of 2016/2017 with the objective to develop an insecticide resistance management program on thrips infesting onion. The first experiment dealt with the evaluation of four different insecticides namely profenofos, λ–cyhalothrin, imidacloprid, and spinetoram in different sequences on thrips population and their effect on yield. The second experiment examined the effect of admixing the surfactant organosilicone with imidacloprid, spinetoram and dimethoate. A Randomized Complete Block Design with three replications was used for both experiments. Data on number of thrips, bulb yield and economic returns were collected. The insecticide imidacloprid and spinetoram resulted in fewer numbers of thrips and higher yields than profenofos and λ –cyhalothrin. Application of the more effective insecticides when the thrips population was high followed by less effective insecticides resulted in better control and higher economic return. Surfactant added insecticides gave a fewer numbers of thrips and higher yields than the corresponding insecticides applied without surfactant. The sequential application of spinetoram and imidacloprid with less effective λ-cyhalothrin and profenofos by mixing with adjuvant are recommended for thrips control as an integral component of thrips management in the Central Rift Valley of Ethiopia.

Litchi is an important subtropical evergreen fruit crop grown in Nepal, which have high nutritive value and refreshing taste. The Litchi growers are experiencing severe loss every year with the damage caused by several insect pests. Among them fruit and shoot borer Conopomorpha sinensis Bradley (Lepidoptera: Gracillariidae) is the one of the important insect pest. Experiments were conducted at RARS Tarahara on existing litchi orchard in RCBD design with four replication and five insecticides (Azadiractin, Chlorantraniliprole, Flubendiamide, Lambda cyhalothrin, and Dimethoate) with recommended doses in litchi orchard against C. sinensis during 2015 and 2016 AD to find out the efficient one. Among the tested insecticide chlorantraniliprole (18.5% w/w SC) and flubendiamide (39.35% m/m SC) each were found to be most efficient against C. sinensis and could be applied at the rate of 1 ml per 3 liter of water when fruit size was about pea and applied 3 times with 10 days interval. This result suggested that these two insecticides could be used for the management for C. sinensis. Farmers may reduce the losses and increase their income with the application of these insecticides

This work was conducted to evaluate the toxicity of some insecticides against honeybee workers under laboratory conditions. Among the tested insecticides, Deltamethrin was the most toxic compound followed by Methomyl while Chlorpyrifos was the least one followed by Profenfos after 24, 48, and 72 hr., of topical exposure. The results indicated that there was negative relationship between the time post treatment and lechal concentration (LC50) values of all the tested insecticides. The LD50 values were 9.5, 10.45, 3.68, 18.33 and 12.55 μg/bee for Methomyl, Cyhalothrin, Deltamethrin, Chlorpyrifos and Profenfos, respectively after 24 hr., of exposure. In this respect, the toxicity of the insecticide Deltamethrin was 2.58 times more than Methomyl, 2.83 times than Cyhalothrin, 4.98 times than Chlorpyrifos and 3.41 times than Profenfos. On the other hand, the toxicity of Methomyl was 1.93 times, more than Chlorpyrifos 1.37 times than Profenfos and 1.1 times than Cyhalothrin. The toxicity of the tested insecticides against the workers of honeybee after 48 hr., of topical exposure showed LD50 values range from 2.44 to 12.32 μg/bee. The insecticide Deltamethrin was the highest toxic compound where as the Chlorpyrifos was the least toxic one. The other insecticides occupied intermediate degree of toxicity. Deltamethrin toxicity in comparision to the other tested insecticides revealed that it was more toxic than Methomyl by 2.21 times, 2.93 times than Cyhalothrin, 5.01 times than Chlorpyrifos and 3.82 times than Profenfos. The LD50 of Deltamethrin was 1.01 mg/l, 0.1mg/l to Methomyl, 5.21 μg/bee to Cyhalothrin, 7.58 mg/l to Chlorpyrifos and 6.11 mg/l to Profenfos. On the other hand, the corresponding LD90 were 2.31 to Deltamethrin, 8.71 to Methomyl, 9.98 to Cyhalothrin, 13.75 to Chlorpyrifos and 15.73 μg/bee to Profenfos. The tested insecticides could be arranged descendingly as follows: Deltamethrin > Methomyl > Cyhalothrin > Profenfos > Chlorpyrifos.

The aim of this study was to investigate the efficiency of four pesticides against the white fly, Bemisia tabaci, infesting squash plants during the two growing season, 2017 and 2018, under field conditions. Results showed that the reduction percentages of the white fly, B.tabaci populations on squash plant during season 2017 caused by Lambda cyhalothrin, Thiamethoxam, Azadirachtin and Beauveria bassiana were 86, 81.5, 72.25 and 86.66%, respectively, as mean residual effect. While, the initial reduction percentages for these pesticides were 98, 96, 93 and 0%, respectively. The general mean percentages of reduction caused by Lambda cyhalothrin, Thiamethoxam, Azadirachtin and B. bassiana were 92, 88.75, 82.63 and 90.33%, respectively. The efficiency of the tested pesticides on white fly could be arranged according to their percentages of reduction in infestation in the follows order: Lambda cyhalothrin > B. bassiana > Thiamethoxam > Azadirachtin, respectively. Results also showed that all the tested pesticides significantly decreased the number of the white fly, B. tabaci in an irregular way compared to the untreated control. Results also cleared that all the tested pesticides caused decrease in white fly populations till 11th day after treatment. The general mean numbers of the white fly, B. tabaci were 18.4, 27.6, 35.8 and 20 individuals/ sample for Lambda cyhalothrin, Thiamethoxam, Azadirachtin and B. bassiana, respectively, comparing with 211.6 individuals/sample in control group.

Aim: The aim of this study is to evaluate the therapeutic role of Citrullus lanatus and Annona muricata fruit Extracts on Cyhalothrin-induced Toxicity. Experimental Design: The study was a completely randomized design employing relevant statistical tools for analysis and interpretation. Place and Duration of Study: The study was carried out in the Reproductive Physiology and Genetics Research Laboratory of the Department of Applied and Environmental Biology, Rivers State University, Rivers State. The experiment lasted for 35 days. Methodology: The body weight of the animals was monitored and recorded twice a week throughout the duration of the experiment. For Biochemical analysis, blood samples were collected by ocular puncture into sterile tubes and serum separated by centrifugation at 2500 g for 10 mins and stored for determination of some liver biomarkers including ALT, ALP, AST, Total Cholesterol and Glucose using their respective kits. For histopathological analysis of Liver and Testis 0.5 g of the each organ was fixed in 10% neutral formalin and sectioned with a digital microtome (AO Spencer, No. 820) at 5 µm thick. Histological sections mounted on slides were stained with Hematoxylin and Eosin (H&E). Photomicrographs were generated at X40 magnification and interpreted. Data from biochemical analyses were subjected to one-way ANOVA. Results: All experimental animals showed a non-significant (P>0.05) increase in body weight throughout the experimental period. The range of values for Organ weight observed in the other treatmental groups were closer to that of the control group than the group exposed to Cyhalothrin only. The level of ALP, AST and ALT significantly p

Field trials were conducted at two locations in Samaru (110 11'' N, 070 38'' E and 686m above sea level) and Maigana (110 10'' N, 070 37'' E and 675m above sea level) both in Northern Guinea Savannah ecological zone of Nigeria during the 2016 wet season to determine the effects of three concentration of aqueous Khaya seed extract (KSE) (20%w/v, 30%w/v and 40%w/v) on damage on cotton (SAMCOT 9) by bollworms. The experimental design was strip plot fitted into randomized complete block design. A total of four sprays at two weeks interval beginning from 9WAS (which corresponded to the period of formation of first square to the detection of first flower) were applied. Data were recorded on the number of terminal shoot damage, number of damaged shed squares, number of damaged shed cotton bolls and number of matured green bolls damaged by bollworms. There was no significant difference in the number of terminal shoot damaged by spiny bollworm (Earias spp.) from spray application of Lambda cyhalothrin, KSE and the untreated control. Significant reduction in the number of shed cotton squares, shed cotton bolls and matured green bolls damaged by bollworms were observed on Lambda cyhalothrin and 40%w/v KSE sprayed plots than the other treatments and the untreated control.