Selenium nanoparticles (SeNPs) have demonstrated significant potential in a variety of disciplines, making them an extremely desirable subject of research. This study investigated the anticancer and antibacterial properties of my-co-fabricated selenium SeNPs, as well as their effects on soybean (Glycine max L.) seeds, seedling growth, cotton leafworm (Spodoptera littoralis) combat, and plant pathogenic fungi inhibition. SeNPs showed anticancer activity with an IC₅₀ value of 1.95 µg/mL against MCF-7 breast adenocarcinoma cells. The myco-synthesized SeNPs exhibited an antibacterial effect against Proteus mirabilis and Klebsiella pneumoniae at 20 mg/mL. The use of 1 µM SeNPs improved soybean seed germination (93%), germination energy (76.5%), germination rate (19.0), and mean germination time (4.3 days). At 0.5 and 1.0 µM SeNPs, the growth parameters of seedlings improved. SeNPs increased the 4th instar larval mortality of cotton leafworm compared to control, with a median lethal concentration of 23.08 mg/mL. They inhibited the growth of Fusarium oxysporum, Rhizoctonia solani, and Fusarium solani. These findings demonstrate that biogenic SeNPs represent a promising approach to achieving sustainable progress in the fields of agriculture, cancer therapy, and infection control.

(1) Background: A molecular hybridization docking approach was employed to develop and detect a new category of naturally activated compounds against Culex pipiens as acetylcholinesterase inhibitors via designing a one-pot multicomponent nano-delivery system. (2) Methods: A nanostructure lipid carrier (NLC), as a second generation of solid lipid nanoparticles, was used as a carrier to deliver the active components of curcumin (Cur), geraniol (G), and linalool (L) in one nanoformulation after studying their applicability in replacing the co-crystallized ligand imidacloprid. (3) Results: The prepared nanostructure showed spherical-shaped, polydisperse particles ranging in size from 50 nm to 300 nm, as found using a transmission electron microscope. Additionally, dynamic light scattering confirmed an average size of 169 nm and a highly stable dispersed solution, as indicated by the zeta potential (−38 mV). The prepared NLC-Cur-LG displayed competitive, high-malignancy insecticidal activity against fourth instar C. pipiens with an elevated rate of death of 0.649 µg/mL. The treatment, due to the prepared nanostructure, affects oxidative stress enzymes, e.g., hydrogen peroxide (4 ppm), superoxide dismutase (SOD) (0.03 OD/mg), and protein carbonyl (0.08 OD/mg), and there are observable upward and downward fluctuations when using different concentrations of NLC-Cur-LG, suggesting significant problems in its foreseeable insecticidal activity. The acetylcholinesterase activity was assessed by an enzyme inhibition assay, and strengthened inhibition occurred due to the encapsulated NLCs (IC₅₀ = 1.95 µg/mL). An investigation of the gene expression by Western blotting, due to treatment with NLC-Cur-LG, revealed a severe reduction of nearly a quarter of what was seen in the untreated group. As a preliminary safety step, the nanoformulation’s toxicity against normal cell lines was tested, and a reassuring result was obtained of IC₅₀ = 158.1 µg/mL for the normal lung fibroblast cell line. (4) Conclusions: the synthesized nanoformulation, NLC-Cur-LG, is a useful insecticide in field conditions.

Increasing incentives for discovering effective and eco-friendly bio-insecticides seem to be a very important challenge nowadays. Plant essential oils play a promising role in integrated pest-management programs. In the present study, the insecticidal activities of six essential oils from clove (Syzygium aromaticum), crane’s-bills (Geranium sp.), citronella (Cymbopogon sp.), dill (Anethum graveolens), cinnamon (Cinnamomum camphora) and basil (Ocimum basilicum) were investigated against the cotton leafworm, Spodoptera littoralis “Boisduval” (Lepidoptera: Noctuidae). The toxicity test revealed that all the tested essential oils have noticeable insecticidal activity. The basil oil was the most efficient against the 3rd instar larvae, with the lethal concentration (LC)50=0.42%; while the dill oil showed higher toxicity than the other oils against the 5th instar larvae (LC50=0.49%) after 48 hours of treatment. The impact of the tested essential oils on the acetylcholinesterase (AChE), carboxylesterase (CE), and glutathione S-transferase (GST) activities was also assessed. The basil oil induced the activity of AChE in both the 3rd and the 5th instar larvae. All tested oils elevated GST activity in the 5th instar larvae, except citronella oil. The dill oil decreased CE activity in both instars. Genotoxicity analysis using comet assay revealed that all assay parameters differed significantly, compared to the control. The maximum percentage of damaged DNA was detected in larvae treated with basil followed by dill, cinnamon, clove, citronella and crane's-bills, respectively. It was concluded that these essential oils could play a promising role in controlling S. littoralis and providing a biological alternative to synthetic insecticides in the control programs.

Background: The susceptibility of pests and natural enemies to conventional insecticides is a critical element in judging the success of integrated pest management programs implementing biological control as a tactic. In this study, the susceptibility of the cotton leafworm Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) to an organophosphorus insecticide (chlorpyrifos) and the entomopathogenic fungus Beauveria bassiana was evaluated through field applications during two successive sugar beet seasons. The populations of the coccinellid, chrysopid, and formicid predators were estimated to indicate pesticide risk assessment strategy. The root and sugar yields were compared during the whole experiment to emphasize the impact of both control strategies on the pre-harvest loss in this strategic crop. Results: Results indicated that over the course of the two seasons of the investigation, chlorpyrifos significantly reduced the population density of S. littoralis and its associated predators. It showed a detrimental effect on S. littoralis larval population than untreated areas, causing an overall reduction of 97 and 92% during the 1st and 2nd seasons, respectively. The biopesticide based on entomopathogenic fungus Beauveria bassiana caused an overall reduction of S. littoralis, reaching 96 and 65% during the 1st and 2nd seasons, respectively. Meanwhile, B. bassiana slightly affects the population of predators compared to insecticide-free areas, so it was recommended for application in sugar beet fields without providing considerable risk to the associated insect predators. The sugar beetroot production and its sugar content increased significantly in both treatments during the two growing seasons compared to non-treated plots. Conclusion: Chlorpyrifos is not recommended for pest control; instead, B. bassiana is considered an effective biopesticide in the Egyptian sugar beet fields infested with S. littoralis as part of an integrated pest management program. Their effect was direct through reducing pest population and indirectly increasing the sugar beetroot production and increasing its total sugar content. Hence, both the sugar beetroot quality and quantity were improved favoring the microbial agent over the chemical insecticide in application for mitigating the chemical hazards toward the associated predators.

Integrated pest management of herbivorous pests relies on combining bio-insecticides and chemical insecticides for a satisfactory population control. The present study focused on evaluating the comparative toxicity of five insecticides, with different modes of action, against third and fifth instar larvae of Spodoptera littoralis and their influence on extent of oxidative stress in insect via detecting vitamin C content as well as measuring the activity of phenol oxidase (PO), catalase (CAT), peroxidase (POX), glutathione-S-transferase (GST) antioxidant enzymes compared to control. The results revealed that emamectin benzoate and indoxacarb were the most potent insecticides among the selected insecticides, based on their respective LC50 values. Thiacloprid, indoxacarb and emamectin benzoate significantly reduced Vitamin C content. Almost all treatments significantly increased PO activity. Only emamectin benzoate and Bacillus thuringiensis significantly induced POX activity. Indoxacarb and emamectin benzoate increased CAT activity in both instar larvae, whereas thiacloprid and indoxacarb decreased GST activity. In conclusion, emamectin benzoate and indoxacarb were the most potent insecticides. Activity of oxidative stress biomarkers upon insecticidal pressure has showed variable response.

<!-- *** Custom HTML *** --> The cotton leaf worm, Spodoptera littoralis, is one of the most injurious agricultural pests in Egypt. In the present study, the interaction between spinosad and Bacillus thuringiensis, using different pairings, in third and fifth instar larvae was determined. Activities of α- and β-non-specific esterases and acetylcholinesterase (AChE) were also determined. Additionally, AChE transcript abundance using the real-time polymerase chain reaction (PCR) was detected. The cumulative percentage mortality of S. littoralis, third and fifth instar larvae, to spinosad and B. thuringiensis were increased gradually by increasing the concentrations. Spinosad was more potent than B. thuringiensis. Sequential application of these bio-insecticides, on the LC₂₅ level on third and fifth instar larvae, when spinosad was first applied, showed synergistic interaction and additive effect, respectively. On the other hand, when B. thuringiensis was first applied, using the same timing of application, additive interaction was observed for both third and fifth instars. Individual, simultaneous and sequential applications of these bio-insecticides induced variable changes in α- and β-esterases and AChE activities. Real-time PCR (qRT-PCR) revealed an increase in transcript abundance up to 2.0-fold in third instar larvae in case of sequential and simultaneous applications. Based on the results herein, integrated pest management programme using spinosad and B. thuringiensis can be successfully developed for the control of S. littoralis.