Insecticide Toxicology

New carbamates that are highly selective for inhibition of Anopheles gambiae acetylcholinesterase (AChE) over the human enzyme might be useful in continuing efforts to limit malaria transmission. In this report we assessed 34 synthesized and commercial carbamates for their selectivity to inhibit the AChEs found in carbamate-susceptible (G3) and carbamate-resistant (Akron) An. gambiaerelative to human AChE. Excellent correspondence is seen between inhibition potencies measured with carbamate-susceptible mosquito homogenate and purified recombinant wild-type (WT) An. gambiae AChE (AgAChE). Similarly, excellent correspondence is seen between inhibition potencies measured with carbamate-resistant mosquito homogenate and purified recombinant G119S AgAChE, consistent with our earlier finding that the Akron strain carries the G119S mutation. Although high (100-to 500-fold) WT An. gambiae vs human selectivity is observed for several compounds, none of the carbamates tested potently inhibits the G119S mutant enzyme. Finally, we describe a predictive model for WT An. gambiae tarsal contact toxicity of the carbamates that relies on inhibition potency, molecular volume, and polar surface area.

Field trials were conducted to study the bio-efficacy of Metarhizium anisopliae (MET) 52EC
against planthoppers in rice for two successive seasons. Weekly and fortnightly spraying with 500, 1000, and
2000 mL/ha of MET 52EC was compared with a standard check, monocrotophos 36 WSC at 1390 mL/ha,
and an untreated check. Weekly applications of MET 52EC reduced the build-up of planthoppers compared
to fortnightly applications. During the 2011 Kharif season, the mean reduction of planthoppers compared
to the untreated check was highest with fortnightly applications of MET 52EC at 1000 mL/ha (83.58%).
The results were almost equal, with the check insecticide, monocrotophos, at 1390 mL/ha (83.88%), and the
subsequent best treatment was a weekly application of MET 52EC at 2000 mL/ha (77.98%). During Rabi
2011–2012, the weekly application of MET 52 EC at 2000 mL/ha (72.14%) and MET 52 EC at 1000 mL/ha
(69.61%) resulted in the highest mean percentage reduction of planthoppers and were higher than the check
insecticide monocrotophos at 1390 mL/ha (67.63%). The average grain yields in both seasons indicated that
monocrotophos at 1390 mL/ha (4121 kg/ha) and weekly application of MET 52 EC at 500 mL/ha (4102 kg/ha)
were significantly similar. MET 52 EC at all dosages did not exhibit any deleterious effects on natural enemies
and did not cause any phytotoxic symptoms

Introduction: Mosquito repellents are most commonly used in Pakistan. Now a day it’s used has increased because of dengue, malaria and yellow fever. There are many types of mosquito repellents including sprays, lotions creams and coils etc. The main constituent of mosquito repellent is DEET which is hazardous to human health. Many people are allergic to these repellents. The aim of current study is to determine the risk and hazards due to the use of mosquito repellents. Methodology: The survey was conducted at different clinics, hospitals, colleges and other different public places with and without complains of reactions on prolong use or even having information regarding toxicity. People presenting with primary complain of skin reactions were significantly due to illiteracy, using cheap and low standard products and excessive use of repellents. Result: Most of the people used mosquito repellents as a precaution to dengue and malaria. Illiterate people preferred coils due to their l...

Exposure to sublethal stressor concentrations, which do not result in mortality, can trigger hormetic responses that enhance growth, reproduction or survival in both primary pest species and their secondary competitors, potentially contributing to the development of insecticide resistance and pest outbreaks. Hormesis, a dose-dependent biphasic response characterized by low-dose stimulation and high-dose inhibition, has garnered increasing attention in entomology and acarology owing to its significant implications for pest management and ecosystem service provision. By contrast, hormesis in natural enemies, such as pathogens, parasitoids and predators, can enhance their biological control performance under specific conditions. Although these responses may offer short-term benefits, they also introduce trade-offs and potential long-term risks. The underlying mechanisms of hormesis include hormonal modulation, stress-induced activation of cellular repair pathways and enhanced detoxification processes. Despite its significance, our understanding of hormesis in ecologically important insects and mites remains limited, with critical knowledge gaps regarding species-specific responses, the influence of environmental factors such as temperature and nutrition, and the long-term ecological consequences of repeated low-dose exposures. Furthermore, the interaction of multiple stressors, such as pesticide mixtures and abiotic factors such as climate change, remains poorly understood in the context of hormetic responses. Future research should focus on elucidating the molecular mechanisms of hormesis, its ecological implications, and the development of predictive models to assess its effects across various ecosystems. Integrating hormesis into pest management strategies could optimize pesticide use while minimizing adverse effects on beneficial organisms. Addressing these gaps is crucial for enhancing ecological resilience, safeguarding populations of beneficial organisms, and promoting sustainable agricultural practices in the face of environmental and anthropogenic challenges.

Rice (Oryza sativa) is a staple food crop consumed worldwide. The brown planthopper (BPH),
Nilaparvata lugens (Stål), inflicts significant damage to rice foliage, causing "hopper burn"
symptoms leading to yield losses ranging from 25 to 70%, depending on infestation levels.
Although insecticides are the primary method for managing BPH, the pest has developed
resistance to many of them, necessitating regular monitoring of insecticide susceptibility to
ensure effective control. To address this, an insecticide bioassay was conducted during the
2024 wet season with field populations from Cuttack, Bargarh, and Raipur. Five insecticides
viz. imidacloprid, dinotefuran, pymetrozine, deltamethrin, and buprofezin (Technical grade)
were tested along with a water-treated control. The rice seedling dip method (IRAC Method 5)
was used to calculate LC50 values, with mortality observations recorded after 72 hours. The
results showed that dinotefuran and pymetrozine caused significantly higher mortality
compared to other treatments. Imidacloprid demonstrated 50% mortality (LC50) at a
concentration of 0.11 mg/L for all tested populations, while pymetrozine recorded an LC50 of
3.47 mg/L across all populations. Dinotefuran exhibited LC50 values of 0.915 mg/L for Cuttack
and 0.76 mg/L for both Bargarh and Raipur populations. The insect growth regulator
buprofezin displayed LC50 values of 0.202 mg/L in all three populations. The significantly
higher efficacy of dinotefuran and pymetrozine suggests that these novel insecticides could be
recommended for rotational use by farmers to effectively manage BPH with minimal chances
of resistance development. In subsequent experiments, based on the field LC50 value of tested
insecticides, the resistance ratio (RR) and cross-resistance may be calculated which will
provide the region-wise resistance and susceptibility insights for better pest control.

The field experiment conducted at Bihar Agricultural College, Sabour Farm of Bihar Agricultural University, Sabour during the year 2010-11 to 2012-13 revealed that pod borer, Helicoverpa armigera on chickpea could effectively be managed through use of pheromone trap + Bt+ HaNPV. Effectiveness of the treatment was also reflected on grain yield which was significantly higher in comparison to other treatments.

Effectiveness of selected IPM modules was evaluated against H. armigera on tomato under field conditions at the farmer’s field at Binuria village near the Sriniketan of Birbhum District of West Bengal, for a year 2015-16 on tomato. The test variety was selected for the study was Patharkuchi, were transplanted in field in randomized complete block design. Nine modules with a non IPM module were evaluated over control and cost benefit ratio of these modules was also estimated. Seven modules were tested with integration of three control strategies i.e., use of Neem seed cake, Bird parching and use of Beauveria bassiana as biocontrol agent except in non IPM and control one. Seven modules included with pesticide of different mode of action, i.e. bio pesticides like B. bassiana, B. thuringiensis and HaNPV and chemical pesticide like Emmamectin benzoate, Spinosad, Flubendiamide, Rynaxypyr respectively. The Non IPM modules contains only chemical component, Cypermethrin. Results revealed tha...

Profenophos EC50 (curcuron 500 PRO) was used in the experiment with 20 concentration of pesticide in range of 0.01% to 1% to find out LC50 for the test plant Vigna radiata, L. grown under laboratory conditions. The parameter used to find out LC50 was germination percentage of seeds after 72 hours of pesticide treatment. The LC 50 is calculated where there is 50 % germination of seeds and was found to be 0.45% of profenofos. The LC 100 (Lethal Concentration) where all seeds failed to germinate was found to be 1% of pesticide concentration. The MAC (maximum allowable concentration) was found to be 0.02% Profenophos.

Elevation of Integrated Pest Management (IPM) in Chickpea was carried out under SCSP project in five adopted villages namely Lakara, Birgua, Belate-Karke, Bdawali and Chokri of district Jhansi during Rabi 2020-21 in farmer's participatory mode using IPM critical inputs. The less pest and diseases incidence was noticed in IPM farmer's field as compared to non IPM farmer's field. The range of Fusarium wilt (FW) in the IPM field of adopted village was only 5-14%, wherein non-IPM field it was 22-32%. Likewise, dry root rot (DRR) and collar rot disease (CR) incidence was reduced in IPM fields as compared to non-IPM fields. The higher mean population of gram pod borer larvae was also observed in non-IPM module with range of 2-3 larvae per plant, while the range of larvae in IPM module was 0.2-0.8 larva per plant. The IPM farmers field yield was 13.20 q/ha, which was 55% higher than non IPM farmers field (8.60 q/ha). Thus, IPM also recorded higher net return (Rs 36580/ha) and BC ratio (1.99) in comparison to non-IPM (net return Rs 21861/ha and BC ratio 2.55). These practices had uplifted the socioeconomic status of farmers and promises to improve further.

Background: The German cockroach (Blattella Germanica (L)) is
one of the synanthrope insects that is an important health pest,
especially in kitchens, restaurants, and hospitals due to the use of
human food scraps and the potential for mechanical transfer of
pathogenic microorganisms. On the other hand, repeated reports
of German cockroach resistance to insecticides indicate the high
potential of this insect in relation to insecticides, so the control options of this pest have gradually decreased and the costs risk of
controlling it due to increasing the dose of insecticides, also toxicity
for the human is constantly enhancing. Therefore, finding new lowrisk solutions with appropriate efficacy to control this insect seems
necessary. According to recent successful studies, using the Nano
silica insecticide effect in pest control of agricultural products
Methods: In this study, the effects of hydrophobic Nano silica
powder on different instars of German cockroaches were investigated.
Results: The results showed high mortality of this insect, especially first and second instar nymphs in contact with hydrophobic
Nano silica. Also, studies with the SEM (Scanning electron microscope) have shown that Nano silica particles adhere to the insect’s
body in large numbers, and cause serious damages such as cuts
and cracks in the cuticle of contacted cockroaches. Also, the tiny
hair loss on the antennae was accompanied by hydrophobic Nano
silica whereas the cockroaches that were killed by CO2 did not have these injuries.
Conclusion: Due to insecticide resistance of German cockroach, this novel approach for control of insect is appropriate

An investigation was designed to explore the “Impact of Training Programmes on Adoption of Vermiculture technology Practices”. This study was conducted in Jorhat district of Assam due to the most of the trained farmers started vermicompost in their houses. 120 numbers of respondents, irrespective of sex were selected from 12 villages of the three blocks had been selected for the present study. Data collection was done by using interview cum questionnaire method. Data revealed that 69.17 per cent of the respondents had medium level of practices towards vermiculture technology. The findings revealed that attending the training programme had showed significant association with practices of the trained farmers towards vermiculture technology.

This particular review explores the multifaceted roles of 14-3-3 proteins in various insect species, including mosquitos, silkworms and houseflies. The research findings have been keen in underscoring of how 14-3-3 proteins regulate the signal transduction, apoptosis and autophagy mitotic cell-check point, along with morphogenetic processes of plant insects. poly-sera raised for various manifested 14-3-3 proteins were noticed in different families (Culicidae and Bombycidae) of insect process with their distinct expression pattern indicative of global and spatio-temporal role in metabolic process. In consistent therein with higher eukaryotes, the 14-3-3 proteins have been known to play a pivotal role in insect cytoskeletal remodelling coupled with focal adhesion mechanisms and bacterial phagocytosis were shed light on the insect innate immunity by 14-3-3 proteins. In the holistic approach of this review on 14-3-3 proteins will address the dynamic roles in the insect species adaptation by modulating the fundamental biological processes such as apoptosis, immunity, and cellular signalling. Furthermore, the development of polyclonal antibodies against mosquito 14-3-3 proteins will offer a promising avenue for studying host-pathogen interactions, with implications for insect-borne disease management.

The effect of the Antifeedant tolfenpyrad in the proportion of activation, synergy, and potentiation of pesticides oxaymatherin, acetamiprid, and lufenuron against Colorado beetle larvae and adults were studied. The results showed Exultance effect on Toxicity. The results also showed Exultance mixing Acetamiprid with antifeedant Tolfenopyrad pesticide toxicity to the activation of the pesticide in the larvae the third instar at a rate of 1.72, where was the rate of potentian reach 1.7. The antifeedant Tolfenopyrad mixture with insecticides Lufenuron and Oxymathrin each alone had antagonism effect where the activation rate reached 0.17 and 0.54 respectively. While the activation effect of mixing antifeedant Tolfenpyrad with the insecticides oxaymatherin, acetamiprid, and lufenuron against adult of Colorado beetle had antagonism effect reached 0.124, 0.524, and 0.614, respectively.

Tomato plants are the second important vegetable crop grown in Egypt. Insect pests pose a serious threat in vegetable production both in terms of quality and quantity. Order Lepidoptera is one of the larger orders in insects. The cotton leafworm, Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) and the leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) are the most serious lepidopterous insect attaching the tomato crop. Pesticides are the basis for defending against major biological disasters and important for ensuring national food security. Nano materials motivate the toxicity of pesticides. In this study the pesticide Marsa 24% SC (belongs to Methoxyfenozide) used for controlling S. littoralis, while Calazole 2% EC (Emamectin Benzoate) applied on T. absoluta. Each pesticide will apply with and without nano cupper complexe salt (1-(2-bromophenyl)-1λ 4-diazane hexadecyltrimethyl-1λ 4-azane, bromo trichloro cuprate (II). Results indicated that the addition of nano salt increases the mortality percentage for both pests (22.45, 59.22 to 100 %) and decreases the lethal time (10 to 3 days; 13 to 4 days) comparing with pesticides without nano salt.

The Colorado potato beetle (CPB) is a serious pest of economically important Solanaceae species. The use of essential oil compounds in pest management has been proposed as an alternative to harmful chemical insecticides that disturb human health and ecosystem functioning. We examined the antifeedant activity of three concentrations (0.125%, 0.25% and 0.5%) of pure camphor and a thujone-camphor mixture against 3rd instar larvae and adults. Their efficacy was evaluated according to the degree of leaf damage and avoidance of treated leaves by the CPB. Treatment of potato leaves significantly reduced leaf damage compared to the control. Leaf protection increased at higher concentrations of the examined compounds. Camphor was more effective against larvae and the thujone-camphor mixture was more effective against adults. Additionally, adults moved faster towards the control leaf disc in the two-choice olfactometer assay if an alternative disc was treated with a thujone-camphor mixture, w...