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Pieris rapae (Lepidoptera: Pieridae) poses a significant threat to Brassicaceae crops, leading to substantial losses annually. Repeated insecticide applications are widely used to protect crops and increase the resistance of P. rapae. Exploring the biochemical and molecular basis of insecticide tolerance in P. rapae is crucial for achieving effective insect suppuration and implementing resistance control strategies. In our research, emamectin benzoate (EBZ) resistance was developed in P. rapae strain through selective pressure over 15 generations. Moreover, the biochemical mechanisms underlying resistance to EBZ and its potential cross-resistance to other insecticides were studied. Additionally, the expression levels of cytochrome P450 (CYP450) and glutathione-s-transferase (GST) genes in P. rapae were quantitatively assessed upon exposure to EBZ using real-time PCR. Our data exhibited that the LC 50 value of susceptible strain (Sus) and EBZ resistance strain (EBZ-R) were 0.009 and 8.09 mg/L, with a resistance ratio (RR) reaching 898.8-fold. The EBZ-R stain displayed notably low cross-resistance to lambda-cyhalothrin, spinetoram, and cypermethrin. However, it demonstrated a moderate level of cross-resistance to deltamethrin. Conversely, no cross-resistance was noted to chlorantraniliprole and indoxacarb. Notably, enzyme inhibitors of detoxification enzymes revealed that piperonyl butoxide (PBO) and diethyl maleate (DEM) enhanced the EBZ toxicity to the resistant strain, indicating the potential involvement of CYP450 and GST in avermectin resistance. A remarkable enhancement in CYP450 and GST activity was observed in the EBZ-R stain. CYP450 and GST genes are upregulated in the EBZ-R stain compared to the Sus strain, which serves as a basis for comprehending the mechanism behind P. rapae resistance to EBZ. The molecular docking analysis demonstrated that EBZ has a high binding affinity with CYP6AE120 and PrGSTS1 with docking energy values of -20.19 and -22.57 kcal/mol, respectively. Our findings offer valuable insights into crafting efficient strategies to monitor and manage resistance in P. rapae populations in Egypt., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study utilizes Mentha piperita (MI) for the first time to investigate the uptake and translocation of chlorpyrifos (CPF; 10 µg g -1 ) from soil, introducing a new approach to improve the efficacy of this technique, which includes using biosurfactants ( Bacillus subtilis and Pseudomonas aeruginosa ) at 10 7 CFU/mL to degrade CPF under greenhouse conditions. Moreover, antioxidant enzymes, including superoxide dismutase (SOD) and peroxidase (Prx), and oxidative stress due to hydrogen peroxide (H 2 O 2 ) and malondialdehyde (MDA) in MI roots and leaves were evaluated under CPF stress. Our results demonstrated that amending soil with MI and B. subtilis followed by P. aeruginosa significantly reduced CPF levels in the soil ( p > 0.05) and enhanced CPF concentrations in MI roots and leaves after 1, 3, 7, 10, and 14 days of the experiment. Furthermore, CPF showed its longest half-life (t 1/2 ) in soil contaminated solely with CPF, lasting 15.36 days. Conversely, its shortest half-life occurred in soil contaminated with CPF and treated with MI along with B. subtilis , lasting 4.65 days. Soil contaminated with CPF and treated with MI and P. aeruginosa showed a half-life of 7.98 days. The half-life (t 1/2 ) of CPF-contaminated soil with MI alone was 11.41 days. A batch equilibrium technique showed that B. subtilis is better than P. aeruginosa for eliminating CPF from soil in In vitro experiments. Notably, CPF-polluted soil treated with coadministration of MI and the tested bacteria improved the activities of SOD and Prx and reduced H 2 O 2 and MDA compared with CPF-polluted soil treated with MI alone. Our findings demonstrated that using B. subtilis and P. aeruginosa as biosurfactants to augment phytoremediation represents a commendable strategy for enhancing the remediation of CPF contamination in affected sites while reducing the existence of harmful pesticide remnants in crop plants.

Acetamiprid (ACDP) is a widely used neonicotinoid insecticide that is popular for its efficacy in controlling fleas in domestic settings and for pets. Our study aims to offer a comprehensive examination of the toxicological impacts of ACDP and the prophylactic effects of cinnamon nanoemulsions (CMNEs) on the pathological, immunohistochemical, and hematological analyses induced by taking ACDP twice a ‎week for 28 days. Forty healthy rats were divided into four groups (n = 10) at random; the first group served as control rats; the second received CMNEs (2 mg/Kg body weight); the third group received acetamiprid (ACDP group; 21.7 mg/Kg body weight), and the fourth group was given both ACDP and CMNEs by oral gavage. Following the study period, tissue and blood samples were extracted and prepared for analysis. According to a GC-MS analysis, CMNEs had several bioactive ingredients that protected the liver from oxidative stress by upregulating antioxidant and anti-inflammatory agents. Our findings demonstrated that whereas ACDP treatment considerably boosted white blood cells (WBCs) and lymphocytes, it significantly lowered body weight gain (BWG), red blood cells (RBCs), hemoglobin (Hb), hematocrit (HCT), and platelets (PLT). ACDP notably reduced antioxidant enzyme activities: superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) and elevated hydrogen peroxide and malondialdehyde levels compared with other groups. ACDP remarkably raised alanine aminotransferase (ALT), aspartate amino transaminase (AST), and alkaline phosphatase (ALP) levels.Moreover, the histopathological and immunohistochemistry assays discovered a severe toxic effect on the liver and kidney following ACDP delivery. Furthermore, cyclooxygenase 2 (COX-2) + immunoexpression was enhanced after treatment with CMNEs. All of the parameters above were returned to nearly normal levels by the coadministration of CMNEs. The molecular docking of cinnamaldehyde with COX-2 also confirmed the protective potential of CMNEs against ACDP toxicity. Our findings highlighted that the coadministration of CMNEs along with ACDP diminished its toxicity by cutting down oxidative stress and enhancing antioxidant capacity, demonstrating the effectiveness of CMNEs in lessening ACDP toxicity., (© 2024. The Author(s).)

Insect glutathione S-transferases (GSTs) serve critical roles in insecticides and other forms of xenobiotic chemical detoxification. The fall armyworm, Spodoptera frugiperda (J. E. Smith), is a major agricultural pest in several countries, especially Egypt. This is the first study to identify and characterize GST genes in S. frugiperda under insecticidal stress. The present work evaluated the toxicity of emamectin benzoate (EBZ) and chlorantraniliprole (CHP) against the third-instar larvae of S. frugiperda using the leaf disk method. The LC 50 values of EBZ and CHP were 0.029 and 1.250 mg/L after 24 h of exposure. Moreover, we identified 31 GST genes, including 28 cytosolic and 3 microsomal SfGSTs from a transcriptome analysis and the genome data of S. frugiperda . Depending on the phylogenetic analysis, sfGSTs were divided into six classes (delta, epsilon, omega, sigma, theta, and microsomal). Furthermore, we investigated the mRNA levels of 28 GST genes using qRT-PCR under EBZ and CHP stress in the third-instar larvae of S. frugiperda . Interestingly, SfGSTe10 and SfGSTe13 stood out with the highest expression after the EBZ and CHP treatments. Finally, a molecular docking model was constructed between EBZ and CHP using the most upregulated genes (SfGSTe10 and SfGSTe13) and the least upregulated genes (SfGSTs1 and SfGSTe2) of S. frugiperda larvae. The molecular docking study showed EBZ and CHP have a high binding affinity with SfGSTe10, with docking energy values of -24.41 and -26.72 kcal/mol, respectively, and sfGSTe13, with docking energy values of -26.85 and -26.78 kcal/mol, respectively. Our findings are important for understanding the role of GSTs in S. frugiperda regarding detoxification processes for EBZ and CHP.

Herbicides reduce the unsafe effects of weeds, but they are likely to have negative impact on essential and secondary metabolism in crops. However, the combined effect of different herbicides on chemical constituents of different varieties of wheat is still not fully obvious. The current investigation was carried out to determine the effects of three post-emergence herbicides (pinoxaden, tribenuron-methyl, and pyroxsulam) on total protein, lipid, and carbohydrate concentrations of three bread wheat cultivars (Misr 1, Giza 171, and Gemmiza 11). These herbicides were added individually and in combinations at recommended and/or half recommended doses. Our findings revealed that the individual application of herbicides decreased total protein and total lipid concentrations in fresh shoots of the three studied wheat cultivars, but increased total carbohydrate concentration. Combined addition of herbicides at recommended and half recommended doses generally decreased the concentrations of total proteins, total lipids, and total carbohydrates. However, the combined addition of tribenuron-methyl and pinoxaden at recommended dose enhanced total protein and total lipid concentrations under Misr1 and Gemmiza 11 cultivars compared to control treatment. Furthermore, the combined addition of tribenuron-methyl and pyroxsulam at half recommended dose enhanced total protein concentration in Giza 171 up to 15.05% and Gemmiza 11 up to 15.09% cultivars, and total lipid concentration in Misr 1 (7.53%) and Giza 171 (9.81%) cultivars against control treatment, where it was the lowest. Total carbohydrate concentration was enhanced by the sole application of pinoxaden by 53.55%, 52.40%, and 51.79% for Misr 1, Giza 171, and Gemmiza 11 cultivars, respectively. Moreover, individual or combined additions of the studied pesticides at recommended and half recommended doses negatively affected wheat grains under all cultivars via decreasing their concentration of nutrients (nitrogen, phosphorus, and potassium) as well as total protein and total carbohydrates. The highest reduction of nitrogen, phosphorus, and potassium concentrations compared to control was observed when tribenuron-methyl+pyroxsulam was applied at the half recommended dose under the three studied cultivars. However, the combined application of tribenuron-methyl+pyroxsulam at the half recommended dose caused the great depression in total proteins and total carbohydrates of wheat grains. Under the stress effect of herbicides, individual application of pinoxaden gave the best results for nitrogen and potassium content as well as total protein and total carbohydrate concentrations in the three studied wheat grain cultivars., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Herbicides are the most effective tool against weed flora in cereal crops that help to maintain and increase crop yields. This investigation was conducted in the winter season of 2018 to study the stress effect of three post-emergence herbicides including pinoxaden, tribenuron-methyl, and pyroxsulam on the biochemical changes at the molecular cell level of wheat. These herbicides were applied either lonely with a rate of 0.45 L.ha -1 , 22.5 gm.ha -1 , and 0.16 Ib a.i/A, respectively, or in combinations together on three Egyptian varieties of bread wheat known as Misr 1, Giza17 1, and Gemmiza 11. Firstly, the abovementioned herbicides were used at the recommended and half recommended doses with their combinations for these varieties to investigate DNA-protein linkage as a signal effect of herbicides at the molecular cell level.Our data showed that the treatment of wheat varieties with the tested herbicides induced new bands with low and high molecular weights of 37.49, 40.08, 146.55, and 147.23 KDa with relative mobility of 0.1574, 0.1603, 0.2166, and 0.2168, respectively. These bands were not presented in the control treatment, suggesting that it might be used as a biochemical marker for plant defense genes. Meanwhile, the control treatment exhibited only five or six bands in the three varieties. However, the tested varieties showed that the same number of bands, the molecular weights of bands, and their relative mobility were significantly varied between the single and the combinations treatment of herbicides. The best treatment was achieved by the combination between pinoxaden and tribenuron-methyl at a recommended dose which induced a large number of protein bands compared to the control treatment on the wheat variety cv. Misr 1, which gave one band with low molecular weight 71.44 KDa at R f 0.1854 and other with the highest molecular weight 147.23 KDa at R f 0.2168, compared to the control treatment.