Efficacy Of Insecticides Research Articles

Seasonal Incidence of Scirtothrips dorsalis and Bemisia tabaci on Chilli with Studies on Comparative Efficacy of Insecticides and Botanical Oils

The study conducted at Sam Higginbottom University of Technology and Sciences in Prayagraj during the 2019 and 2020 kharif seasons provided comprehensive insights into insect population dynamics and insecticide efficacy against thrips and whiteflies in chilli cultivation. Key findings revealed significant pest population fluctuations, with thrips peaking at 16 per plant during the 43rd Standard Meteorological Week (SMW) in late October for both years. Whitefly populations reached up to 17.6 per plant, peaking during the 44th week in 2019 and the 43rd week in 2020, both in late October. Correlation analyses showed significant negative relationships between insect populations and temperature, wind velocity, and rainfall, while a positive correlation was observed with sunshine duration. Multiple linear regression models demonstrated that weather parameters collectively explained 69.8% and 70.4% of thrips population variability in 2019 and 2020, respectively, and 87.7% and 17.2% of whitefly population variability. Stepwise regression models revealed that in 2019, maximum temperature and rainfall jointly accounted for 46% of pest population variability. In 2020, the addition of wind velocity to these factors explained 83% and 56% of variability in thrips and whitefly populations, respectively. Insecticide efficacy evaluation showed acetamiprid as most effective against thrips (92.14% reduction) and imidacloprid against whiteflies (88.89% reduction). Thiamethoxam and imidacloprid demonstrated comparable effectiveness. Economic analysis highlighted imidacloprid's superiority, providing effective pest control, the highest chili yield, and the best cost-benefit ratios (1:8.30 in 2019 and 1:5.38 in 2020).

Efficacy of Various Insecticides against Leaf Folder Cnaphalocrocis medinalis (Guenee) in Rice and the Calculation of the Benefit-cost Ratio

The present investigation was conducted at Heera Puri research field, Institute of Agriculture and Natural Sciences, Deen Dayal Upadhyaya Gorakhpur University, Gorakhpur during Kharif, 2023. The relative effectiveness of six insecticides viz., Flubendiamide 39.35 % SC, Chlorpyriphos 20 EC, Acephate 95 SC, Chlorantraniliprole 18.5 SC, Fipronil 5 SC, Cartap hydrochloride 50% SP and Control. The study revealed that the treatment Flubendiamide 39.35% SC was found most effective followed by Chlorantraniliprole 18.5 SC, and Fipronil 5 SC whereas the highest infestation was recorded in the control plot. The significantly higher grain yield was obtained in Flubendiamide 39.35% SC treated plots which are followed by Chlorantraniliprole 18.5 SC, Fipronil 5 SC, Cartap hydrochloride 50% SP, Acephate 95 SC and Chlorpyriphos 20 EC. The highest increase in yield over control was reported in the plot treated with Flubendiamide 39.35% SC followed by Chlorantraniliprole 18.5 SC, Fipronil 5 SC, Cartap hydrochloride 50% SP, Acephate 95 SC, and Chlorpyriphos 20 EC. The economics of various treatments based on net profit and cost of plant protection revealed that. the highest cost: benefit ratio of Chlorpyriphos 20 EC was followed by Chlorantraniliprole 18.5 SC, followed by Acephate 95 SC, Fipronil 5 SC and the lowest benefit-cost ratio was reported in plots treated with Cartap hydrochloride 50% SP.

Management of Okra Shoot and Fruit Borer Earias vitella (Fab.) by Different Insecticides on Okra

The okra shoot and fruit borer (Earias vittella) is a significant pest affecting okra crops. It bores into the shoots and fruits, causing stunted growth and reduced yield. To combat this pest the present study was conducted during Kharif, 2023 at Rainfed Agriculture Research Farm, Department of Entomology, Bundelkhand University Jhansi. The investigation was carried out to evaluate the efficacy of different insecticides against okra shoot and fruit borer Earias vitella (Fab.), Nine insecticides including control (untreated) were sprayed three times on the okra crop resulted all treatments were significantly effective over control. Among all treatments emamectin benzoate 5% SG was found best effective to control the shoot and fruit infestation caused by E. vitella in all three sprays followed by fluebendiaminde 480% EC and spinosad 45% SC. Among all treatments maximum C:B ratio was obtained from the emamectin benzoate 5% SG (147.56 qt/hac and 1:1.57) followed by spinosad 45% SC (1:1.46), indoxacarb 14.5% SC (1:1.37).

Efficacy and economics of biorational insecticides against mustard aphid, Lipaphis erysimi (Kalt)

Efficacy and economics of biorational insecticides against mustard aphid, Lipaphis erysimi (Kalt)

Efficacy of newer insecticides against aphids (Aphis gossypii Glover) in Bt cotton

Efficacy of newer insecticides against aphids (Aphis gossypii Glover) in Bt cotton

Field efficacy of insecticides for suppressing white mango scale insect (Aulacaspis tubercularis Newstead) (Hemiptera: Diaspididae) in southwest Ethiopia

White mango scale (WMS) Aulacaspis tubercularis Newstead (Hemiptera: Diaspididae) is a polyphagous armored scale insect which is considered one of the key pests of mango (Mangifera indica L.) around the world. Mango is widely grown in Ethiopia whereas its production is challenged by WMS in the last decade. Effective formulations that could help manage the scale as part of IPM practice were sought from field experiments at Seka mango farm, Ethiopia in 2019 and 2020 seasons. The study aimed to evaluate the efficacy of some formulations against WMS on mango trees. Randomized complete block designs with three replications were used for the experiments and each tree served as a plot. Allocation of each treatment within each replication was done randomly. The treatments were applied sequentially three times at 14 days interval using motorized Knapsack sprayer coinciding with peak period of natural infestation. Scale numbers before and after each spray were counted using a microscope with LCD. Sum of live crawler, female and male was registered as WMS count data. Results showed that dimethoate, diazinon, imidacloprid & λ-cyhalothrin sprayed alone; dimethoate rotated with imidacloprid & λ-cyhalothrin, chlorpyrifos-ethyl rotated with paraffin, and diazinon rotated with azadirachtin, caused total mortality of the scales. The results also showed that, chlorpyrifos-ethyl, deltamethrin, paraffin oil and λ-cyhalothrin sprayed alone caused percent reduction with range 83–95 % in both seasons. Hence, the study revealed that dimethoate, diazinon, imidacloprid & λ-cyhalothrin applied individually, dimethoate rotated with imidacloprid & λ-cyhalothrin, chlorpyrifos-ethyl rotated with paraffin and diazinon rotated with azadirachtin fully protect mango trees from WMS and significantly superior to other treatments. Therefore, chemical control of A. tubercularis may consider the use of these materials as foliar application and can be used as components for integrated pest management plans for WMS. However, application in the form of rotation is preferred to the alone spray as the former could substantially reduce the likelihood of inducing pesticide resistance. Cost implications and effects of the products on the natural enemy and residual toxicity in fruits need to be studied.

Graphene powders as new contact nanopesticides: Revealing key parameters on their insecticidal activity for stored product insects

The overuse and reliance on pesticides has caused insects to develop resistance with global concerns. To address this problem extensive research is directed to find new and sustainable alternatives using chemical-free and resistance-free solutions for pest control. This paper presents a comprehensive investigation of the insecticidal properties of several types of industrially produced graphene powder materials such as graphene and graphene oxide (GO) with micro- and nano size and different structural and chemical properties as new contact nanopesticides against three major stored grain insects: the rice weevil Sitophilus oryzae (L.), the lesser grain borer, Rhyzopertha dominica (F.)˙ and the larger grain borer, Prostephanus truncatus Horn. Bioassays were performed using different concentrations, i.e., 0, 100, 500 and 1000 ppm of graphene powders on the mortality of selected adult insects recorded after 3, 7, 14, and 21 days of exposure and progeny production after 65 days. Results showed that graphene oxide (GO) has no insecticidal efficacy while graphene powders with nano-size particles showed significantly enhanced insecticidal performance compared to micron-size graphene powders. The observed insecticidal effects are explained by the higher probability that nano-sized graphene particles adhere on the insect body compared to large particles. The mortality is proposed as the result of physical mode of action of attached graphene nanoparticles causing stronger interruption of the protective cuticle layer, gas respiratory functions and faster mortality. The findings of this study revealed that it is important to select graphene materials with optimal structural and interfacial properties to achieve the highest insecticidal performance in potential development of a new generation of sustainable insecticides.

Efficacy of Various Insecticides against Gram Pod Borer (Helicoverpa armigera) Hubner in Chickpea

The investigation sought to examine the efficacy of several pesticides on the larval population of the gram pod borer (Helicoverpa armigera) in chickpea plants, as well as the corresponding cost-benefit ratio. The experiment was carried out in the Entomology Research Field, Institute of Agriculture and Natural Sciences, Deeksha Bhawan, DDU Gorakhpur University, Gorakhpur in a Randomized Block Design (RBD) with seven treatments replicated three times using Pusa 362 variety in a plot size of (3 m×2 m) at a spacing of (20×10 cm). The treatments used during the observation were T1 Spinosad, T2 NSKE, T3 Bt, T4 Beauveria bassiana, T5 Neem oil, T6 Emamectin benzoate and T7 control plot (without any treatment). From the study it was noted that the highest reduction was reported in plots treated with Spinosad 0.20ml/l which proved to be superior among the rest of the treatments and the next effective treatment is Emamectin benzoate 0.4 g/l, followed by Beauveria bassiana 2x 10 CFU@ 5ml/l, Bacillus thuringiensis 1.5g/l and maximum population of pod borer was observed in untreated control plot. The data on the yield of chickpea revealed that the highest yield recorded in the treatment Spinosad (0.20ml/l) and it was superior over all the other treatment followed by Emamectin benzoate 0.4g/l with the yield was obtained in the control. The data on the increase in yield over control of chickpea revealed that the highest increase in yield over control was recorded in the treatment Spinosad (0.20ml/l) and it was superior over all the other treatments and followed by Emamectin benzoate 0.4g/l with the lowest increase in yield over control was reported in plot treated with NSKE 5% with, respectively. The maximum cost-benefit ratio was obtained in the plot treated with 0.20ml/l spinosad 45 SC next effective treatment in terms of cost-benefit ratio was Emamectin benzoate 0.4g/l and the lowest cost-benefit ratio was found in Neem oil 3%treated plot.

Microbiota-driven vaccination in soft ticks: Implications for survival, fitness and reproductive capabilities in Ornithodoros moubata.

The Ornithodoros moubata (Om) soft tick, a vector for diseases like tick-borne human relapsing fever and African swine fever, poses challenges to conventional control methods. With diminishing insecticide efficacy, harnessing the tick's microbiota through innovative approaches like microbiota-driven vaccination emerges as a promising strategy for sustainable and targeted disease control. This study investigated the intricate relationship between Pseudomonas, a keystone taxon in the Om microbiome, and its impact on tick fitness, microbiome structure and network dynamics. Utilizing in silico analyses and empirical vaccination experiments, the role of Pseudomonas within microbial networks in the tick midguts (MG) and salivary glands (SG) of Om was studied. Additionally, the consequences of anti-microbiota vaccines targeting Pseudomonas and Lactobacillus on tick fitness, microbiome diversity and community assembly were explored. The result of the study shows that in Om, Pseudomonas plays a central role in microbial networks, influencing keystone species despite being categorized as peripheral (interacting with 47 different taxa, 13 of which are keystone species). Anti-microbiota vaccination targeting Pseudomonas and Lactobacillus yields distinct effects on tick fitness, with Pseudomonas vaccination significantly impacting female tick survival, while Lactobacillus significantly reduced oviposition and fertility. Microbiome changes post-vaccination reveal diversity alterations, emphasizing the impact of vaccine choice. Community assembly dynamics and network robustness analyses highlight Pseudomonas' pivotal role, in influencing topological features and network resilience. The findings of the study provide comprehensive insights into the intricate dynamics of Om microbial networks and the potential of targeted microbiota-driven vaccines for tick control.

Efficacy of Various Ready-mix Insecticides against Spodoptera litura (Fab.) in Groundnut

Efficacy of Various Ready-mix Insecticides against Spodoptera litura (Fab.) in Groundnut

Size-dependent effect on controllable release and field insecticidal efficacy of diamide insecticide polylactic acid microspheres delivery systems against Ostrinia nubilalis

New nano/microcarriers of pesticides represent a highly promising novel field for sustainable pest management. However, despite extensive laboratory research, few studies on the design and evaluation of nanopesticides for field applications exist. In this study, we present a straightforward and green synthetic method of ultrasonic-assisted and hydrogen-bonded self-assembly at the oil-water interface for the synthesis of polylactic acid (PLA) microspheres encapsulating chlorantraniliprole (CAP), with precise control over the size of the microspheres. The resulting CAP-loaded PLA microspheres (CAP-PLA MS) exhibit both high pesticide encapsulation efficiency and stability in natural environments. It has been determined that non-Fickian diffusion mainly controls pesticide release, thus enabling dynamic control over molecular transport speeds. Importantly, our functional CAP-PLA MS demonstrates superior sustained pesticide release performance under both laboratory and field conditions while maintaining better exceptional insecticidal efficacy than normal CAP in controlling O. nubilalis at a concentration of 30 or 45 g/ha. Consequently, we propose that our functional PLA microspheres could serve as ideal pesticide carriers in the sustained treatment of O. nubilalis.

Cellulase-responsive hydroxypropyl cellulose-anchored hollow mesoporous silica carriers for pesticide delivery

In this study, a cellulase-responsive controlled-release formulation (FPR-HMS-HPC) was developed by grafting hydroxypropyl cellulose (HPC) onto fipronil (FPR) loaded hollow mesoporous silica (HMS) nanoparticles via ester linkage. The FPR-HMS-HPC formulation was characterized using scanning and transmission electron microscopies, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The results indicated that FPR-HMS-HPC exhibited a high loading capacity of 10.0 % (w/w) and demonstrated favorable responsiveness to cellulase enzyme. Moreover, its insecticidal efficacy against Reticulitermes flaviceps surpassed that of an equivalent dose of FPR. Toxicology studies showed that the mortality and hatching rates of zebrafish exposed to FPR-HMS-HPC nanoparticles were reduced by >6.5 and 8.0 times, respectively. Thus, HPC-anchored HMS nanoparticles as insecticide delivery systems present a sustainable method for pest control significantly reducing harm to non-target organisms and the environment.

Efficacy of Biopesticides and Insecticides against Lepidopteran Pests in Rainfed Castor

Field experiments were conducted during kharif 2022 to evaluate the bio-efficacy of biopesticides and insecticides against tobacco caterpillar, Spodoptera litura (F.);semilooper, Achaea janata L. and shoot and capsule borer, Conogethes punctiferalis Guenee on castor. The results revealed that, all the insecticide treatments were significantly superior over untreated control. The highest% reduction of lepidopteran pest complex over the control after three sprays was recorded with spinetoram 11.7 SC followed by cyantraniliprole 10.26 OD, Bacillus thuringiensis var. kurstaki (Btk) SC, profenophos 50 EC, lambda cyhalothrin 5 EC and B. thuringiensis var. kurstaki (Btk) WP 1.5, Beauveria bassiana SC and Neemazal 10000 PPM. Highest seed yield was recorded with spinetoram (1434 kg/ ha) followed by cyantraniliprole (1338 kg/ ha) as against 940 kg/ ha in untreated control. The maximum incremental cost-benefit ratio of 1:3.13 was obtained with application of spinetoram followed by lambda-cyhalothrin (1:3.00) and Btk SC (1:2.73).

Phytotoxic effect and efficacy of chemical insecticides used for management of mulberry thrips on natural enemy (Coccinellid) population

Phytotoxic effect and efficacy of chemical insecticides used for management of mulberry thrips on natural enemy (Coccinellid) population

In vivo efficacy of date palm pit extract based chromone derivative against Aedes aegypti dengue vectors in Saudi Arabia

AbstractThis study investigated the in vivo efficacy of a chromium derivative extracted from date palms pit against Aedes aegypti the third instar larvae, the known vector of dengue fever in Saudi Arabia. Chromone 1, a flavonoid chromone component, was isolated from the alcoholic extract of date palm pits (DPP) using High‐performance liquid chromatography (HPLC). The results showed that exposure of A. aegypti larvae to whole DPP extract and chromone 1 for 24 h resulted in significant insecticidal efficacy with LC50 values of 132.82 and 54.64 ppm, respectively. The same concentrations also effectively inhibited AChE (acetylcholinesterase) activity up to −56.83 and −58.58%, respectively, compared to controls. The acetylcholine bromide test further confirmed the interaction between chromone 1 and AChE. The results also revealed that the chromone 1 treatment altered Deoxyribonucleic Acid (DNA) and protein content. It also exhibited that the extract of date palm pits DPP can effectively serve as sustainable ingredients for the control management of A. aegypti.

Molecular identification and eco-friendly management of rice brown planthoppers in Bangladesh

Infestation by various insect pests is the main constraint for growing rice where rice brown planthopper (Nilaparvata lugens Stål) can severely damage rice plants directly through feeding. Therefore, the study aims to detect rice brown planthoppers (BPH) and provide environment-friendly management tactics to mitigate the problem which caused by brown planthoppers. The BPH samples were collected from rice fields of different locations in the Patuakhali of Bangladesh for molecular identification. A molecularly single species of rice brown planthopper, Nilaparavata lugens was identified using mitochondrial cytochrome oxidase subunit I (mtCOI) universal marker. The nucleotide sequences of collected samples were compared with other nucleotide sequences from the GenBank database of NCBI, which make single clades in the phylogenetic tree at an insignificant distance. Moreover, brown planthopper management observations were recorded in laboratory conditions after providing an artificial diet with different treatments of plant-based insecticides Neem oil (1 %, 5 %, and 10 %), Castor oil (1 %, 5 %, and 10 %) where only 20 % sucrose solution was used as negative control and Abamectin (1 %, 5 % and 10 %) were also used as a positive control for comparing the efficacy of plant-based insecticides on rice brown planthoppers. The results showed the highest mortality (100 %) of rice brown planthoppers was recorded by Abamectin 10 %, followed by Abamectin 5 %. Neem 10 % performed better than Abamectin 1 % during 1st hour. Initial after exposure of 2nd hour for Abamectin 1 % revealed greater mortality (59 %) than Neem 10 %. Neem 5 % showed less effect on mortality in brown planthopper than Neem 10 % but was higher than Neem 1 % during 6 h of observation. The Castor oil of 10 % caused higher mortality than the Castor of 5 % but not up to the marks of Abamectin and different concentrations of Neem oil. Castor oil of 1 % and control have shown no mortality of brown planthopper for 6 h of observation.

LARVICIDAL EFFICACY OF ALCOHOL-BASED EXTRACTION OF VERNONIA AMYGDALINA WITH BACILLUS THURINGIENSIS ON THE VECTOR AEDES AEGYPTI

Mosquitoes are the most significant category of hematophagous arthropods. Traditional medicine uses numerous plants for their larvicidal properties against mosquitoes in various regions globally. The combination of bacterial toxin and plant extract has a significant impact on mosquito larvae. We evaluated the larvicidal effectiveness of the plant extract Vernonia amygdalina in combination with B. thuringiensis against third instar larvae of Aedes aegypti. We recorded the average mortality and percentage mortality of larval populations at various concentrations after 24 and 48 hours of exposure. Bti and Vernonia amygdalina extracts showed significant insecticidal efficacy, as evidenced by LC 50 and LC 90 values. The LC50 values for 24-hour and 48-hour exposure are 18.35 and 16.71, respectively. The LC 90 values at 24 hours and 48 hours of exposure are 32.47 and 29.39, respectively.

Functional regulation of microRNA-184 in the replication and infection of Autographa californica multiple nucleopolyhedrovirus

MicroRNAs (miRNAs) represent a class of short, non-coding RNAs that are widely acknowledged as crucial participants in virus-host interactions. MiR-184, a highly conserved and abundant miRNA in insects, has yet to be extensively studied for its involvement in baculovirus infection. In this study, we investigated how miR-184 affects the infection and replication of Autographa californica multiple nucleopolyhedrovirus (AcMNPV). The results indicated that after AcMNPV infection, there was an initial increase in the expression of miR-184 within 24 h, followed by a subsequent decrease. MiR-184 can inhibit AcMNPV's DNA replication and budded virus production by directly targeting four viral genes, namely ie1, ac66, p49, and lef9. Moreover, suppressing miR-184 expression enhanced the insecticidal efficacy of AcMNPV against Spodoptera exigua larvae and markedly elevated the host ATPase gene expressions. These findings showed that miR-184 had a substantial impact on the interactions between baculoviruses and insects, presenting a prospective candidate for developing highly effective miRNA-based biopesticides.

Indoor residual spraying of experimental huts in Cameroon highlights the potential of Fludora® Fusion to control wild pyrethroid-resistant malaria vectors

Elevated resistance to pyrethroids in major malaria vectors has led to the introduction of novel insecticides including neonicotinoids. There is a fear that efficacy of these new insecticides could be impacted by cross-resistance mechanisms from metabolic resistance to pyrethroids. In this study, after evaluating the resistance to deltamethrin, clothianidin and mixture of clothianidin + deltamethrin in the lab using CDC bottle assays, the efficacy of the new IRS formulation Fludora® Fusion was tested in comparison to clothianidin and deltamethrin applied alone using experimental hut trials against wild free-flying pyrethroid-resistant Anopheles funestus from Elende and field An. gambiae collected from Nkolondom reared in the lab and released in the huts. Additionally, cone tests on the treated walls were performed each month for a period of twelve months to evaluate the residual efficacy of the sprayed products. Furthermore, the L1014F-kdr target-site mutation and the L119F-GSTe2 mediated metabolic resistance to pyrethroids were genotyped on a subset of mosquitoes from the EHT to assess the potential cross-resistance. All Anopheles species tested were fully susceptible to clothianidin and clothianidin + deltamethrin mixture in CDC bottle assay while resistance was noted to deltamethrin. Accordingly, Fludora® Fusion (62.83% vs 42.42%) and clothianidin (64.42% vs 42.42%) induced significantly higher mortality rates in EHT than deltamethrin (42.42%) against free flying An. funestus from Elende in month 1 (M1) and no significant difference in mortality was observed between the first (M1) and sixth (M6) months of the evaluation (P > 0.05). However, lower mortality rates were recorded against An. gambiae s.s from Nkolondom (mortality rates 50%, 45.56% and 26.68%). In-situ cone test on the wall showed a high residual efficacy of Fludora® Fusion and clothianidin on the susceptible strain KISUMU (> 12 months) and moderately on the highly pyrethroid-resistant An. gambiae strain from Nkolondom (6 months). Interestingly, no association was observed between the L119F-GSTe2 mutation and the ability of mosquitoes to survive exposure to Fludora® Fusion, whereas a trend was observed with the L1014F-kdr mutation. This study highlights that Fludora® Fusion, through its clothianidin component, has good potential of controlling pyrethroid-resistant mosquitoes with prolonged residual efficacy. This could be therefore an appropriate tool for vector control in several malaria endemic regions.

Unveiling the molecular composition and biological properties of essential oil derived from the leaves of wild Mentha aquatica L.: A comprehensive in vitro and in silico exploration

Abstract The purpose of the current study is to assess the chemical profile, antioxidant, antimicrobial, and insecticide efficacy of essential oil derived from the leaf of Moroccan Mentha aquatica L. (MA-EO) using in vitro and in silico analysis. Using GC-MS/MS analysis, 18 components of MA-EO were identified, including linalool (42.42%), α-elemol (10.45%), α-terpineol (8.07%), linalyl acetate (7.37%), and caryophyllene (4.05%). Additionally, MA-EO has a strong antioxidant capacity with IC50 values of 0.64 ± 0.01 µg/mL using the DPPH assay and 0.167 ± 0.13 µg/mL using the ABTS test. Total antioxidant capacity activities were found to be 188.21 ± 0.31 mg EAA/g, while RP activities were 1.95 ± 0.023. The powerful antibacterial properties of MA-EO were proven to be effective against Escherichia coli and Candida albicans. MA-EO showed insecticidal potential using the fumigation experiment, with an LC50 of 3.33 μL/L in the air after 24 h of exposure. At a dose of 20 µL/mL, MA-EO reduced fertility, fecundity, and emergence of adult C. maculatus. MA-EO had 95% mortality at the same dosage. In silico analysis revealed that the antioxidant activity of MA-EO is linked to γ-eudesmol, while its antibacterial efficacy is associated with phenol, 2,4-di-tert-butyl-, and its antifungal capacity with phenol, 2,4-di-tert-butyl-. MA-EO demonstrates potent bactericidal, fungicidal, and bioinsecticide properties, making it effective for controlling bacteria, fungi, and insect pests in stored grains.