Agricultural Insecticides Research Articles

From Proline to Chlorantraniliprole Mimics: Computer-Aided Design, Simple Preparation, and Excellent Insecticidal Profiles.

Chlorantraniliprole (CHL), a favored agricultural insecticide, is renowned for its high efficiency and broad-spectrum effectiveness against lepidoptera insects. However, the urgency for new insecticide development is underscored by the intricate multistep preparation process and modest overall yields of CHL, along with the escalating challenge of insect resistance. In response, we have crafted CHL mimics from proline employing computer-aided drug design. Molecular docking analysis of CHL's interactions with the ryanodine receptor (RyR) revealed that the nitrogen atom within the pyrazole moiety does not engage in pivotal interactions. Its removal may not abolish bioactivity entirely but could substantially simplify the synthetic process, thereby enhancing atom economy. This revelation prompted the exclusion of nitrogen and the subsequent formation of a pyrrole ring, enabling the meticulous design of synthetic pathways characterized by cost-effective precursors, streamlined synthesis, the avoidance of toxic reagents, minimal instrumentation, and high yields in the pursuit of innovative RyR modulators. Among these modulators, A1 and B1, obtained with yields exceeding 60%, showcased exceptional insecticidal potency, with LC50 values spanning from 0.12 to 1.47 mg L-1 against P. xylostella and M. separate. The inhibitory effects of these two compounds on insect detoxification enzymes imply a reduced likelihood of eliciting resistance in comparison to CHL, a finding further corroborated by their insecticidal potency against resistant pests. Moreover, molecular docking, MD simulations, and DFT calculations provided valuable structural insights, potentially unraveling the superior insecticidal activity of these two molecules, and thus paving the way for developing more potent insecticides.

Design, Synthesis, and Insecticidal Activity of Isoxazoline Derivatives Incorporating an Acylhydrazine Moiety.

The long-term use of agricultural insecticides has led to the development of resistant strains. In this context, the isoxazoline structure has become an active area of pesticide research owing to its wide insecticidal spectrum, nontoxicity to mammals, and lack of cross-resistance with known insecticides. In the present study, based on the discovery of compound G22 in our previous work, a series of novel isoxazoline compounds containing acylhydrazine were designed and synthesized using a scaffold hopping strategy. The insecticidal activities of the target compounds were assessed, and compound L17 (LC50 = 0.489 mg/L) showed insecticidal activity against Spodoptera frugiperda superior to those of the commercial insecticides indoxacarb (LC50 = 3.14 mg/L) and fluralaner (LC50 = 0.659 mg/L). Theoretical calculations indicated that the introduction of acylhydrazine plays an important role in the biological activity of the target compounds. Furthermore, the enzyme-linked immunosorbent assay and molecular docking results indicated that L17 may act on the GABA receptor of the target insect. These results indicated that L17 is a potential candidate compound for controlling S. frugiperda populations in agriculture.

Insecticide-Induced Metabolic Dysregulation in Model Microbe E. coli Discovered by Comprehensive Metabolic Profiling.

Fipronil, malathion, and permethrin are widely used insecticides in agriculture, public areas, and residential spaces. The globally abused application of these chemicals results in residues surpassing established maximum residue levels, giving rise to potential toxicity in unintended organisms. Long-term exposure and the persistent accumulation of these insecticides in animals and humans pose threats such as neurotoxicity, liver and kidney damage, and microbiota dysbiosis. Despite the known risks, the specific impact of these insecticides on gut microbiota and their metabolic processes, as well as the subsequent effects on host health, remain largely unknown. This study aimed to address this gap by utilizing nonpathogenic Escherichia coli as a representative of human gut bacteria and examining its growth and metabolic perturbations induced by exposure to fipronil, malathion, and permethrin. Our research showed that exposure of E. coli to fipronil, malathion, and permethrin at physiologically relevant concentrations resulted in significant growth inhibition. Furthermore, we have observed the biodegradation of fipronil and permethrin by E. coli, while no biodegradation was found for malathion. Thus, E. coli is capable of degrading fipronil and permethrin, thereby enabling the removal of those substances. Next, we studied how insecticides affect bacterial metabolism to understand their influence on the functions of the microbes. Our metabolomics analysis revealed chemical-dependent alterations in metabolic profiles and metabolite compositions following insecticide exposure. These changes encompassed shifts in carboxylic acids and derivatives, organooxygen compounds, as well as indoles and their derivatives. To gain a deeper insight into the systematic changes induced by these insecticides, we conducted a metabolic pathway analysis. Our data indicated that fipronil, compared with malathion and permethrin, exhibited opposite regulation in glycine, serine, and threonine metabolism and valine, leucine, and isoleucine biosynthesis. In summary, our study demonstrates the capability of E. coli to degrade fipronil and permethrin, leading to their removal, while malathion remains unaffected. Additionally, we reveal chemical-dependent alterations in bacterial metabolism induced by insecticide exposure, with specific impacts on metabolic pathways, particularly in pathways related to amino acid metabolism.

The association between prenatal pyrethroids exposure and children's health - current research.

Exposure to pyrethroids, a widely used agricultural, forestry, and household insecticide, is a major public health concern due to its potential health effects on children. The aim of this review was to summarize the current knowledge of the effects of prenatal exposure to pyrethroids on the course and outcome of pregnancy, health status, and neurobehavioural development of children. A systematic and comprehensive search of the PubMed, Web of Science, and Scopus databases was conducted during January-February 2024. The review included original articles published in peerreviewed English-language journals since 2015. Based on keywords, 198 studies were identified and screened for eligibility. Ultimately, the review analyzed 25 articles including 16 that assessed the effects of prenatal exposure to pyrethroids on children's neurobehavioural development, 3 studies that assessed the effects on the course and outcome of pregnancy, and further 3 focused on respiratory disease. In addition, 1 study analyzed the development of obesity and 2 studies examined the effects on children's growth, weight and body composition in early childhood. In conclusion, there is considerable uncertainty about the adverse effects of prenatal exposure to pyrethroids on children's health. The strongest evidence has been reported for neurobehavioural development although results are also inconsistent. Further research is needed to understand the mechanisms of action and health effects of pyrethroids in susceptible populations. Int J Occup Med Environ Health. 2024;37(4).

Novel Insecticidal Pyridylhydrazono Derivatives Identified via Scaffold Hopping and Conformation Regulation Strategies.

Insect transient receptor potential vanilloid (TRPV) channels are critical targets for insecticides. In this study, various scaffold-hopping strategies were employed in the rational design of pyridylhydrazono derivatives as potential insect TRPV channels modulators. Insecticidal bioassay demonstrated that the initial target compounds exhibited lower insecticidal activity compared to pymetrozine, with the optimal compound B3 exhibiting a mortality rate of 53.3 % against Aphis craccivora at 400 mg L-1. Conformation analysis indicated that the high energy barrier required for the transition from the lowest-energy conformation to the active conformation may be a key factor contributing to the reduced insecticidal activities of the target compounds. Further structural optimizations aimed at reducing this energy barrier through binding mode-based conformation regulation led to the identification of optimal target 4-(3'-pyridylhydrazono)pyrazol-5-one derivatives C1 and C2. These compounds exhibited reduced transition energy barriers and improved insecticidal activity, with moderate mortality rate of 66.3 % and 75.7 % against A. craccivora at 400 mg L-1, respectively. These findings provide valuable insights for future research on the discovery of insect TRPV modulators and have significant implications for the development of more effective agricultural insecticides.

Effect and investigating of oxygen / nitrogen on modified glassy carbon electrode chitosan/carbon nanotube and best detection of nicotine using Cyclic voltammetry measurement technique

Nicotine, a component of tobacco smoke, is a neurotoxin. It exerts its effects by stimulating nicotine-containing acetylcholine receptors. Nicotine, one of over 4,700 components in tobacco smoke, was previously used as an insecticide in agriculture. Although the use of nicotine in agriculture has been banned in many countries, nicotine poisoning due to accidental or intentional ingestion of nicotine products remains a problem for smoking workers as well as children and adults. Understanding the mechanisms of nicotine poisoning is important for both prevention and treatment, as well as for appropriate regulatory approaches. We study the pharmacological properties of nicotine and the cellular mechanisms underlying acute and persistent nicotine addiction that appear to be related to the central and peripheral nervous systems. The electrochemical properties of nicotine were studied using a glassy carbon-chitosan/multiwalled carbon nanotubes-COOH electrode. Nicotine-COOH via chitosan/multiwalled carbon nanotubes was irreversibly reduced in the presence of oxygen and nitrogen gas. Oxidation signals at lower potentials and higher currents were obtained for nicotine via the modified electrode compared to the glassy carbon electrode. This condition proliferated in the presence of oxygen gas, suggesting that nanotubes, including carbon nanotubes, facilitate electron transfer and form the basis for electrocatalytic nicotine applications. Under optimal conditions, cyclic voltammetry (CV) shows oxidation of nicotine in the presence of oxygen at 0.74 V and nitrogen at 0.81 V in phosphate buffer solution at pH = 7.4. Linear calibration curves range from 0.1 to 200 μM for oxygen and 0.05 to 200 μM for nitrogen conditions, both with R2 = 0.99, and detection limits of 7.1 for oxygen and 9.2 nM for nitrogen.

Isocycloseram, a novel isoxazoline insecticide seed treatment for protection of wheat and barley and mortality of wireworms, Limonius californicus (Coleoptera: Elateridae).

Populations of various economic species of wireworms are increasing in the key cereal crop production areas of Canada and the United States. To address this problem, seed treatments are under development that both provide crop protection and significantly reduce populations equivalent in effectiveness to the formerly used but now deregistered organochlorine lindane. Herein, we evaluated isocycloseram (PLINAZOLIN technology), the first isoxazoline (GABA-gated Chloride Channel Allosteric Modulator) agricultural insecticide, as a seed treatment for the protection of cereal crops from the sugarbeet wireworm, Limonius californicus (Mannerheim). In wheat and barley field trials conducted over 4 years under extreme wireworm pressure, isocycloseram applied as a seed treatment at 5.0-7.5 g AI/100 kg seed was as effective as or more effective than the current industry standard thiamethoxam at 20.0 g AI/100 kg seed in protecting crop stand and yield. Isocycloseram also reduced neonate wireworms (produced from eggs during the growing season) and resident wireworms (in the field at the time of planting) to levels expected from the formerly used seed treatment lindane.

A Sensitive SERS Sensor Combined with Intelligent Variable Selection Models for Detecting Chlorpyrifos Residue in Tea.

Chlorpyrifos is one of the most widely used broad-spectrum insecticides in agriculture. Given its potential toxicity and residue in food (e.g., tea), establishing a rapid and reliable method for the determination of chlorpyrifos residue is crucial. In this study, a strategy combining surface-enhanced Raman spectroscopy (SERS) and intelligent variable selection models for detecting chlorpyrifos residue in tea was established. First, gold nanostars were fabricated as a SERS sensor for measuring the SERS spectra. Second, the raw SERS spectra were preprocessed to facilitate the quantitative analysis. Third, a partial least squares model and four outstanding intelligent variable selection models, Monte Carlo-based uninformative variable elimination, competitive adaptive reweighted sampling, iteratively retaining informative variables, and variable iterative space shrinkage approach, were developed for detecting chlorpyrifos residue in a comparative study. The repeatability and reproducibility tests demonstrated the excellent stability of the proposed strategy. Furthermore, the sensitivity of the proposed strategy was assessed by estimating limit of detection values of the various models. Finally, two-tailed paired t-tests confirmed that the accuracy of the proposed strategy was equivalent to that of gas chromatography-mass spectrometry. Hence, the proposed method provides a promising strategy for detecting chlorpyrifos residue in tea.

A 10-year retrospective study of the risks and peculiarities in pediatric patients with (para)gonadal tumors and cysts.

Gonadal pediatric tumors are rare, ranking fourth (6%) among pediatric tumors, by Surveillance, Epidemiology, and End Results Program (https:∕∕seer.cancer.gov∕). They have vague symptoms, leading to late discovery, but early detection and identifying its risk factors result in favorable prognosis and reduction of its incidence respectively. A 10-year retrospective study identified peculiarities and risk factors in 210 children till age 17 with (para)gonadal tumors. Stress, pollution (agricultural chemicals, insecticides and metal mine), obesity, breastfeeding ≤5 months, malformations [mainly non-genetic related 67∕87 (77%), especially eye malformation - 64%], hormone, smoking, positive heredo-genetic history, rural residence area, abnormal birth weight, and menstruation disorders showed an increased gonadal malignancy risk; relative risk ratio (RR): 1.33, 1.30, 1.34, 1.11, 1.65, 1.16, 1.36, 1.10, 1.00, 1.08 and 1.15 folds, respectively. RR for histopathological subtypes: immature teratoma (IT) (pollution - 1.75, Rhesus positive - 3.41), dysgerminoma (menstruation disorders - 2.80), granulosa cell tumor (stress - 2.10, menstruation disorders - 2.80), mucinous cystadenomas (obesity - 2.84, no postnatal vaccine - 3.71), mature teratomas (stress - 2.35, malformations - 2.18) and serous cystadenomas (breastfeeding ≤5 months - 2.53), dependent variables being mixed germ cell tumors (GCTs) and cysts. Children presenting with bleeding (73%), abdominal distention (62%), elevated tumor markers (91%), (multilocular) solid tumor (88% and 100%), tumor size >10 cm (65%), GCTs (74%), death (100%), metastases (100%), viruses (77%), loss of appetite (68%), and weight (85%), had gonadal malignant tumors, especially mixed GCTs and IT. Avoiding these risk factors will prevent and reduce gonadal pediatric tumors. Investigating children presenting with the listed peculiarities, especially if exposed to the mentioned risk factors, will enable early gonadal tumor identification, successful patient management, and favorable prognosis.

Novaluron and indoxacarb induced methemoglobinemia – unveiling a rare poisoning

Introduction and aim. In India, the utilization of agricultural pesticides for intentional self-poisoning is a prevalent method, and it is associated with substantially higher fatality rates compared to other self-poisoning approaches. Plethora, an agricultural insecticide containing novaluron (5.25%) and indoxacarb (4.5%), has recently been introduced and widely used in India and various other regions for its broad-spectrum lepidopteran control. While there have been documented cases of isolated self-poisoning involving indoxacarb, there is currently no literature reporting incidents of human poisoning specifically related to novaluron. Description of the case. An 83-Year-old male was presented to the emergency department (ED) with a history of consumption of 50 mL of an insecticide suspension concentrate called ‘PLETHORA’ to commit suicide. He had one episode of vomiting and dizziness after the ingestion. There was associated cyanosis, and the patient was put on high-flow oxygen at 10 L/min through a face mask. The patient was diagnosed to have methemoglobinemia and was successfully treated with methylene blue and ascorbic acid. One hour post methylene blue injection showed a methemoglobin level of 1%, and the patient gradually improved. Patients presenting with novaluron and indoxacarb poisoning require supportive treatment as there is no specific antidote. There should be a high index of suspicion for methemoglobinemia in such patients, and timely management is necessary to prevent further complications. The patient was successfully managed and discharged after the 3rd day of admission. Conclusion. The management of patients with novaluron and indoxacarb poisoning primarily involves supportive care, as there is currently no specific antidote available for these substances. Maintaining a high suspicion index for the development of methemoglobinemia and timely management of other complications is crucial for the best possible patient outcomes.

Integrated approaches for Solenopsis invicta (Hymenoptera: Formicidae) management: insights from laboratory studies with entomopathogenic nematodes and insecticides.

In agricultural pest management, especially in combatting the invasive red imported fire ant (RIFA, Solenopsis invicta), significant challenges emerge as a consequence of the constraints of solely depending on chemical insecticides or entomopathogenic nematodes (EPNs). The utilization of chemical insecticides carries environmental and ecological hazards, whereas EPNs, when applied independently, might not offer the immediate effectiveness necessary for adequate RIFA suppression. Acknowledging these hurdles, our study investigates a synergistic method that integrates EPNs with chemical insecticides, aiming to fulfill the urgent demand for more efficient and environmentally friendly pest control solutions. Our evaluation focused on the interaction between the highly pathogenic Steinernema riobrave 7-12 EPN strain and prevalent insecticides, specifically beta-cypermethrin and a mixture of bifenthrin and clothianidin, applied at highly diluted recommended concentrations. The findings revealed a notable increase in RIFA mortality rates when EPNs and these insecticides were used together, outperforming the results achieved with each method individually. Remarkably, this enhanced efficacy was especially evident at lower concentrations of the bifenthrin-clothianidin mixture, indicating a valuable approach to minimizing reliance on chemical insecticides in agriculture. Furthermore, the high survival rates of EPNs alongside the tested insecticides indicate their compatibility and potential for sustained use in integrated pest management programs. Our research underscores the effectiveness of merging EPNs with chemical insecticides as a powerful and sustainable strategy for RIFA management. This combined approach not only meets the immediate challenges of pest control in agricultural settings, but also supports wider environmental objectives by reducing the dependency on chemical insecticides. © 2024 Society of Chemical Industry.

Microglial gp91phox-mediated neuroinflammation and ferroptosis contributes to learning and memory deficits in rotenone-treated mice

Apart from dopaminergic neurotoxicity, exposure to rotenone, a commonly used insecticide in agriculture, also adversely affects hippocampal and cortical neurons, resulting in cognitive impairments in mice. We recently established a role of microglia-mediated neuroinflammation in rotenone-elicited deficits of cognition, yet the mechanisms remain elusive. Here, we investigated the involvement of NADPH oxidase 2 (NOX2) catalytic subunit gp91phox in rotenone-induced cognitive deficits and the associated mechanisms. Our study demonstrated that rotenone exposure elevated expression of gp91phox and phosphorylation of the NOX2 cytosolic subunit p47phox, along with NADPH depletion in the hippocampus and cortex of mice, indicating NOX2 activation. Specific knockdown of gp91phox in microglia via adeno-associated virus delivery resulted in reduced microglial activation, proinflammatory gene expression and improved learning and memory capacity in rotenone-intoxicated mice. Genetic deletion of gp91phox also reversed rotenone-elicited cognitive dysfunction in mice. Furthermore, microglial gp91phox knockdown attenuated neuronal damage and synaptic loss in mice. This intervention also suppressed iron accumulation, disruption of iron-metabolism proteins and iron-dependent lipid peroxidation and restored the balance of ferroptosis-related parameters, including GPX4, SLC711, PTGS2, and ACSL4 in rotenone-lesioned mice. Intriguingly, pharmacological inhibition of ferroptosis with liproxstatin-1 conferred protection against rotenone-induced neurodegeneration and cognitive dysfunction in mice. In summary, our findings underscored the contribution of microglial gp91phox-dependent neuroinflammation and ferroptosis to learning and memory dysfunction in rotenone-lesioned mice. These results provided valuable insights into the pathogenesis of cognitive deficits associated with pesticide-induced Parkinsonism, suggesting potential therapeutic avenues for intervention.

Ragi Pest Control

The rise of global population has put increasing pressure on the agriculture industry to meet the demand for food. However, the growing use of pesticides and insecticides in conventional farming practices has caused significant harm to the environment and human health. Thus, there is a growing interest in using sustainable agriculture practices that reduce the use of these harmful chemicals. One such practice is pest detection, which enables farmers to detect pests in their crops before they cause significant damage. In this context, this project aims to develop a pest detection system using IoT and Arduino. The system will be designed to detect pests in crops through a combination of sensors and machine learning algorithms. The system will consist of an Arduino microcontroller, soil moisture sensors, temperature and humidity sensors, infrared sensors or camera modules, and a Wi-Fi or Bluetooth module. The sensors will collect data on soil moisture levels, temperature, humidity, and pest activity. The data will be sent to a cloud-based server or database for analysis and visualization. The infrared sensor or camera module will detect the presence of pests in the crops. The system will use machine learning algorithms to distinguish between pests and other objects, such as leaves or debris. When pests are detected, the system will alert the farmer through a buzzer or LED connected to the Arduino board. The farmer can then take appropriate action, such as applying pesticide or removing infested plants. The pest detection system has the potential to reduce the use of harmful pesticides and insecticides in agriculture, as farmers will be able to identify pests before they cause significant damage. The system will also provide farmers with real-time information on pest activity, enabling them to take proactive measures to control pests and reduce crop damage. Additionally, the system can track and store the pest detection data over time, allowing farmers to monitor trends and patterns in pest activity. In conclusion, this project proposes the development of a pest detection system using IoT and Arduino that will enable farmers to monitor pest activity in their crops in real-time. The system has the potential to reduce the use of harmful chemicals in agriculture and improve crop yield while ensuring sustainable and environmentally friendly practices.

Leucine improves thiram-induced tibial dyschondroplasia and gut microbiota dysbiosis in broilers

Thiram, a commonly used agricultural insecticide and fungicide, has been found to cause tibial dyschondroplasia (TD) in broilers, leading to substantial economic losses in the poultry industry. In this study, we aimed to investigate the mechanism of action of leucine in mitigating thiram-induced TD and leucine effects on gut microbial diversity. Broiler chickens were randomly divided into five equal groups: control group (standard diet), thiram-induced group (thiram 80 mg/kg from day 3 to day 7), and different concentrations of leucine groups (0.3%, 0.6%, 0.9% leucine from day 8 to day 18). Performance indicator analysis and tibial parameter analysis showed that leucine positively affected thiram-induced TD broilers. Additionally, mRNA expressions and protein levels of HIF-1α/VEGFA and Ihh/PTHrP genes were determined via quantitative real-time polymerase chain reaction and western blot. The results showed that leucine recovered lameness disorder by downregulating the expression of HIF-1α, VEGFA, and PTHrP while upregulating the expression of Ihh. Moreover, the 16 S rRNA sequencing revealed that the leucine group demonstrated a decrease in the abundance of harmful bacteria compared to the TD group, with an enrichment of beneficial bacteria responsible for producing short-chain fatty acids, including Alistipes, Paludicola, CHKCI002, Lactobacillus, and Erysipelatoclostridium. In summary, the current study suggests that leucine could improve the symptoms of thiram-induced TD and maintain gut microbiota homeostasis.

An in situ one-step route for the synthesis of Fe3O4@ZIF-8 core-shells with a high-peroxidase-like performance for the colorimetric detection of methyl parathion

Methyl parathion (MP) is a broad-spectrum agricultural insecticide. Human exposure to MP can affect the nervous, cardiovascular, and hepatic systems. In this research, a core–shell Fe3O4@zeolitic imidazolate framework-8 (ZIF-8) is developed as a peroxidase mimic for the rapid and simple colorimetric detection of MP. Fe3O4 nanoparticles were wrapped with ZIF-8 by a hydrothermal method to obtain core–shell structural Fe3O4@ZIF-8 nanocomposites. The synthesized Fe3O4@ZIF-8 possessed mimetic properties and effectively catalyzed the conversion of transparent solution to blue upon the oxidation of 3, 3′, 5, 5′-tetramethylbenzidine (TMB) by H2O2. Further, based on a classical reaction through acetylthiocholine chloride (ATCl) and cholesterol oxidase (ChOx), acetylcholinesterase (AChE) can generate H2O2, and that MP can exert an inhibitory effect on AChE. Within the range of 10 to 200 µg/L, the MP concentration demonstrated a remarkable linear response with the absorbance under optimum conditions, with a detection limit of 6.3 μg/L. Finally, the proposed approach enabled the detection of MP in cabbage. As an artificial peroxidase, Fe3O4@ZIF-8 demonstrated greater affinity for the substrate than horseradish peroxidase, which has a great application prospects in food safety and environmental safety.

Multifaceted Effects of Subchronic Exposure to Chlorfenapyr in Mice: Implications from Serum Metabolomics, Hepatic Oxidative Stress, and Intestinal Homeostasis.

As chlorfenapyr is a commonly used insecticide in agriculture, the health risks of subchronic exposure to chlorfenapyr remained unclear. This study aimed to extensively probe the health risks from subchronic exposure to chlorfenapyr at the NOAEL and 10-fold NOAEL dose in mice. Through pathological and biochemical examinations, the body metabolism, hepatic toxicity, and intestinal homeostasis were systematically assessed. After 12 weeks, a 10-fold NOAEL dose of chlorfenapyr resulted in weight reduction, increased daily food intake, and blood lipid abnormalities. Concurrently, this dosage induced hepatotoxicity and amplified oxidative stress in hepatocytes, a finding further supported in HepG2 cells. Moreover, chlorfenapyr resulted in intestinal inflammation, evidenced by increased inflammatory factors (IL-17a, IL-10, IL-1β, IL-6, IL-22), disrupted immune cells (RORγt, Foxp3), and compromised intestinal barriers (ZO-1 and occludin). By contrast, the NOAEL dose presented less toxicity in most evaluations. Serum metabolomic analyses unveiled widespread disruptions in pathways related to hepatotoxicity and intestinal inflammation, including NF-κB signaling, Th cell differentiation, and bile acid metabolism. Microbiomic analysis showed an increase in Lactobacillus, a decrease in Muribaculaceae, and diminished anti-inflammatory microbes, which further propelled the inflammatory response and leaded to intestinal inflammation. These findings revealed the molecular mechanisms underlying chlorfenapyr-induced hepatotoxicity and intestinal inflammation, highlighting the significant role of the gut microbiota.

Laboratory evaluation of a bio-insecticide candidate from tangerine peel extracts against Trialeurodes vaporariorum (Homoptera: Aleyrodidae).

The excessive use of synthetic insecticides in modern agriculture has led to environmental contamination and the development of insect resistance. Also, the prolonged use of chemical insecticides in producing flowers and tomatoes in greenhouses has caused health problems for workers and their offspring. In this study, we analyzed the efficacy of mandarin peel (Citrus reticulata L.) essential oil (EO) as a natural insecticide against greenhouse whitefly (Trieurodes vaporariorum W., Homoptera: Aleyrodidae), a common pest in greenhouse production of different crops. Petroleum ether (PET) and n-hexane (HEX) were used as solvents to extract essential oil (EO) from tangerine peels. The yield of EO was 1.59% and 2.00% (m/m) for PET and HEX, respectively. Additionally, the insect-killing power of EO was tested by checking how many greenhouse whiteflies died at different times. The results showed that PET and HEX extracts of tangerine EO effectively controlled greenhouse whiteflies. Furthermore, with both solvents, a 12.5% (v/v) application was as practical as the commercial insecticide imidacloprid. Further characterization tests with the polarimeter, FTIR, HPLC-RP, and GC-MS showed that the essential oil (EO) contained about 41% (v/v) of d-limonene and that this compound may be responsible for the observed insecticidal properties. Therefore, tangerine peel essential oil is an excellent botanical insecticide candidate for controlling greenhouse whiteflies.

Synthesis and biological evaluation of folic acid-rotenol conjugate as a potent targeted anticancer prodrug

Rotenone, a plant-based agricultural insecticide, has been shown to have anti-tumor activity through targeting mitochondrial complex I in cancer cells. However, off-target toxic side effect on nervous systems have greatly restricted the application of rotenone as anticancer drugs. Here, a folic acid-rotenol (FA-rotenol) conjugate was prepared by covalent coupling of the tumor-targeting ligand folic acid with rotenone derivative—rotenol to enhance its accumulation at tumor site. FA-rotenol conjugates present high in vitro cytotoxicties against several cell lines by inducing mitochondrial membrane potential depolarization and increasing the level of intracellular reactive oxygen species (ROS) to activate the mitochondrial pathway of apoptosis and enhance the G2/M cell cycle arrest. Because of the high affinity with over-expressed folate receptors, FA-rotenol conjugate demonstrated more effective in vivo therapeutic outcomes in 4T1 tumor-bearing mice than rotenone and rotenol. In addition, FA-rotenol conjugate can markedly inhibit the cell migration and invasion of HepG-2 cells. These studies confirm the feasibility of tumor-targeted ligand conjugated rotenone derivatives for targeted antitumor therapy; likewise, they lay the foundations for the development of other rotenol-conjugates with antitumor potential.

Chemical composition, toxicity, and repellency of some Myrtaceae plants essential oils against Tribolium castaneum (Herbst)

Essential oils (EOs) obtained from plants have the potential to be environment-friendly alternatives to synthetic insecticides in agriculture. Tribolium castaneum (Herbst) is a cosmopolitan pest that causes the loss of a major proportion of stored crops. Therefore, we studied the insecticidal and repellent effects of EOs derived from the plants viz. Eucalyptus rudis, Eucalyptus crebra, and Melaleuca genistifolia against larvae and adults of T. castaneum. Essential oils were derived from the leaves of each plant using hydro-distillation. Gas chromatography-mass spectrometry (GC-MS) of the extracted EOs revealed that eucalyptol, viridiflorol, α-terpineol, and eugenol methyl comprised the major components of the EOs. However, the composition and quantity of the compounds varied across EOs. Specifically, EOs derived from E. rudis exhibited the highest fumigation toxicity against adult and larval T. castaneum, followed by M. genistifolia and E. crebra. In the presence of wheat grains, fumigation toxicity against T. castaneum declined by nearly threefold. Contact toxicity assays revealed that EOs from E. rudis were overall the most effective against the pest (LC50: 0.392 μL/cm2 for adult; LC50: 0.471 μL/cm2 for larva) followed by M. genistifolia (LC50: 0.424 μL/cm2 for adult; LC50: 0.478 μL/cm2 for larva) and E. crebra (LC50: 0.471 μL/cm2 for adult; LC50: 0.515 μL/cm2 for larva). The LC50 value of each EO was up to five times lower in adults than in larvae. Melaleuca genistifolia was the most effective repellent against T. castaneum adults; however, its effectiveness decreased with increasing exposure time. In conclusion, the EOs of E. rudis, E. crebra, and M. genistifolia were all viable green biopesticide alternatives to synthetic insecticides.

New infestation records of two-spotted spider mites on potato tubers under storage conditions and response of genotypes at Kulumsa, Ethiopia

The study sought to ascertain spider mite prevalence, infestation, and identification and to assess the response of potato genotypes. In 2022, this pest was only observed on some genotypes in December. In late January, an infestation, incidence, and severity increased from 10 to 13 genotypes on potato tuber stocks stored for irrigation experiments. Those genotypes were planted in irrigated fields, and the sprouted tuber losses ranged from 12.5% to 100% and up to 15.38% in the 2022 and 2023 records, respectively. Following this, spider mites, often known as two-spotted spider mites (TSSM) or Tetranychus urticae, were identified. This is the first time a potato sprout infestation has been recorded in Ethiopia. The two-spotted spider mites damaged the tubers quantitatively by sucking the moisture of sprouts up to the 5th grade, with 97 and >75% infestation levels, incidence, and severity, respectively. The pest grows very rapidly and hastens the drying of sprouted tuber leaves. Some genotypes were resistant to TSSM and recovered after the sprouts were infected and dried, which were treated with pesticides in 2023. The typical agricultural insecticides were ineffective in controlling the pest in the first year, and a Profenofos was applied in the second year. Thus, seed tubers are the main production limit unless appropriate research efforts are undertaken and management techniques are created. Int. J. Agril. Res. Innov. Tech. 13(2): 55-63, Dec 2023