Conventional Pesticides Research Articles

β-Caryophyllene wrapped by nanoliposomes efficiently increases the control effect on Bemisia tabaci MED

Bemisia tabaci poses a severe threat to plants, and the control of B. tabaci mainly relies on pesticides, which causes more and more rapidly increasing resistance. β-Caryophyllene is a promising ingredient for agricultural pest control, but its feature of poor water solubility need to be improved in practical applications. Nanotechnology can enhance the effectiveness and dispersion of volatile organic compounds (VOCs). In this study, a nanoliposome carrier was constructed by ethanol injection and ultrasonic dispersion method, and β-caryophyllene was wrapped inside it, thus solving the defect of poor solubility of β-caryophyllene. The size of the β-caryophyllene nanoliposomes (C-BT-NPs) was around 200 nm, with the absolute value of the zeta potential exceeding 30 mV and a PDI below 0.5. The stability was also maintained over a 14-d storage period. C-BT-NPs showed effective insecticidal activity against B. tabaci, with an LC50 of 1.51 g/L, outperforming thiamethoxam and offering efficient agricultural pest control. Furthermore, C-BT-NPs had minimal short-term impact on the growth of tomato plants, indicating that they are safety on plants. Therefore, the VOCs using nanoliposome preparation technology show promise in reducing reliance on conventional pesticides and present new approaches to managing agricultural pests.

Enhancing garlic propagation through functional biopolymer-based propagules coatings: A bio-nanotechnological strategy

Integrating agricultural, chemical, and technological knowledge is crucial for developing bio-nanotechnologies to improve agricultural production. This study explores the innovative use of biopolymeric coatings, based on sodium alginate and sodium alginate + Laponite® (nanoclay), containing biostimulants (tryptophol and thymol) or not, on garlic cloves. These coatings were analyzed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR-ATR), and scanning electron microscopy (SEM). Greenhouse bioassays showed improvements in garlic shoot plant biomass with both treatments: sodium alginate biopolymer and sodium alginate biopolymer plus Laponite®. In the field experiment, garlic plants treated with sodium alginate, in combination with conventional pesticide treatments, resulted in better quality garlic bulbs, where larger garlics were harvested in this treatment, reducing commercial losses. In tropical garlic crops, obtaining plants with greater initial vigor is essential. Our results highlight the potential of these bio-nanotechnological strategies to enhance garlic propagation, ensuring environmental protection and food security.

'The Garlic Gambit': an alternative strategy for controlling vine weevil (Otiorhynchus sulcatus F.; Coleoptera: Curculionidae).

Plant protection products derived from plant material are proposed to be a sustainable alternative to conventional synthetic chemical pesticides. This study determines the efficacy of a commercially available bioinsecticide based on garlic (Allium sativum L.; Asparagales: Amaryllidaceae) extract against vine weevil (Otiorhynchus sulcatus F.; Coleoptera: Curculionidae) eggs and larvae in contact, fumigation and a combination of contact and fumigation bioassays under laboratory conditions. Results showed that garlic significantly reduced egg hatch rate compared to the control group when applied as a fumigant. Similarly, the egg hatch rate was reduced compared to the control group when garlic was applied as combined contact and fumigant applications. No effect was observed when the garlic product was applied as a contact application. The bioinsecticide significantly reduced larval survival when either contact or fumigant applications were used. A combined contact and fumigant effect was shown also when vine weevil eggs were exposed to the bioinsecticide for 30 days in plastic containers containing growing media. The number of larvae recovered after this period was significantly reduced compared to the control group. This study demonstrates the potential of garlic-based bioinsecticides, such as Pitcher GR, for vine weevil control. Further studies are, however, needed to determine the efficacy of such bioinsecticides under field conditions and investigate how these products can be most effectively used as a part of a wider vine weevil integrated pest management program.

Role of Microorganisms in Shaping Insect-plant Interactions

Plants and insects have a strong interaction in the natural world, and it turns out that the little organisms known as microbes have a significant influence on how they interact. Extremely tiny living creatures called microorganisms are crucial to these interactions. Some of them work in tandem with plants to produce compounds that function as natural insect repellents. These microbes receive food from the plants in return, which allows them to survive. Furthermore, certain microbes that reside inside insects alter their behaviour and even what they eat. They may increase the likelihood that bugs will consume a certain plant or possibly lessen their resistance to the plant's defenses. Furthermore, microbes have the power to alter their environment, including the soil, by converting detritus into plant food, which influences the plants' resistance to disease and other external stresses. All of this is being studied by scientists to develop safer alternatives to conventional pesticides for protecting plants and insects. Gaining knowledge about how these microscopic organisms affect the relationships between insects and plants may help us maintain a balanced environment and healthy plants. This manuscript investigates how microorganisms influence the interactions between plants and insects. It explores how microbes aid plants in producing natural insect repellents and how they affect insect behavior and diet. The study also looks into how microorganisms impact soil health and plant resistance. Understanding these roles can lead to sustainable alternatives to conventional pesticides.

Harnessing Koelreuteria paniculata Seed Extracts and Oil for Sustainable Woolly Apple Aphid Control

The woolly apple aphid—WAA (Eriosoma lanigerum Hausmann, 1802) poses a significant threat to intensive apple production. Given the limitations of conventional synthetic pesticides, there is an urgent need for effective and sustainable pest management strategies. Botanical extracts derived from plants with insecticidal properties mitigating aphid populations without adverse environmental impacts are scarce where WAA is concerned. Thus, the pertinent study aimed to investigate the aphicidal potential of Koelreuteria paniculata seed ethanolic extract (derived from the seed coat) and mechanically extracted oil (derived from the seed itself). At concentrations of 2.5% and 5%, both solutions expressed undeniable insecticidal potential, providing absolute (100%; oil) or significant (86–100%; ethanolic extract) mortality rates both in vivo and in vitro. Predominant phenolic compounds determined in the ethanolic extract were gallic and protocatechuic acids and three derivates—p-coumaric, quercetin, and luteolin acid derivates—contributing to more than 90% of the total phenolic content, while phenolic compounds were not detected in the oil, indicating activity of different active compounds. Although deriving from different seed parts and distinct extraction methods, both ethanolic extract and oil exhibited significant aphicidal effects against WAA. The integration of botanical extracts from invasive species into pest management practices supports ecological balance and sustainable agricultural productivity, fostering a healthier environment and more resilient agricultural systems.

An integrated methods to manage the corn ground beetle (Zabrus tenebrioides Goeze) in wheat field

This study presents a series of experiments on control techniques in the open field trials to monitor and manage the corn ground beetle (Zabrus tenebrioides Goeze) (Coleoptera: Carabidae). The larval stage is particularly harmful, as it feeds on cereal roots and constructs tunnels that damage the wheat crop while residing in the soil. The primary goal of the study was to investigate the effectiveness of various control measures in managing Z. tenebrioides populations and improving wheat yields. Thus, in Qalanchughan village three wheat varieties, the local (Hawler2, Hwler4) and the imported one (Wafia) were tested in the underground (prevention measures) such as organic fertilizers, biofertilizer, chemical fertilizers and chemical pesticides and aboveground (control measure) like biopesticides and conventional pesticides. Regarding the underground prevention measures the lowest population of insect was 0.48 larvae/M2 with the highest biological yield (7132.22 kg/ha) of the cereal found in combined soil and seed treatment (organic humic acid + seed mycorrhizal fungi). The lowest population was found in the local variety Hawler4 which was 0.61 larvae/M2 and the highest population was found in Wafia which was 1.04 larvae/ M2. On the other hand, the aboveground treatments also differ in their effectiveness against Z. tenebrioides thus the lowest population of the larvae in 1/M2 was found in the chemical pesticide, Alphacypermethrin 0.38 larvae/ M2 that was not significantly different from Eucalyptus globulus extract which was 0.60 larvae/ M2. Furthermore, maximum biological yield and treatment efficiency were found in Alphacypermethrin followed by eucalyptus extract which was (5581.11 kg/ha and 108.54). The biopesticides and plant extracts can be used as part of integrated pest management techniques to lower the beetle populations and encourage sustainable farming.

Efficacy of Neem Oil against Termite [Odontotermes obesus (Rambur)] (Blattodea: Termitidae)

Botanical pesticides are of great importance in Integrated Pest Management (IPM). Extracts of different plant parts are used for deterring and killing the various life stages of insects. Most of the oils produced by plants contain bioactive compounds with insecticidal properties. Neem oil containing azadirachtin is an established insecticide and insect repellent. Use of synthetic pesticides for wood preservation leads to environmental pollution and health hazards to human beings and other living organisms. To avoid these problems neem, Azadiracta indica (A.Juss.) plant oil was used in this study and gave better results. The weight loss of card boards treated with neem was less like chlorpyrifos treated cardboards. Gravimetric measurements of cardboards shown 18.34gm and 16.85 gm weight which after 30 and 60 days of exposure to A. indica oil indicated that plant oil has potential effects like conventional pesticides like chlorpyrifos which showed the18.72 and 18.63 gm of weight in cardboards after 30 and 60 days of exposure. The P values was 0.036457 and 0.016527 for cardboards exposed to two treatments after 30 and 60 days respectively which is highly significant.

Heterologous expression of distinct insecticidal genes in potato cultivars encodes resistance against potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae)

AbstractThe potato tuber moth, Phthorimaea operculella (Zeller), is a notorious insect pest of potato incurring substantial yield losses in the field as well as in storage. Chemical control is difficult to exercise due to the latent feeding of the caterpillars and their ability to develop resistance against insecticides. One of the essential components of efficient insect-resistant management is using two or more different insecticidal genes in transgenic crops to effectively avoid and delay the resistance development in insect pests. Two constructs, namely DS-1 (cry3A + SN-19 genes) and DS-2 (OCII + SN-19 genes) in pCAMBIA1301 binary vector, were developed and were transformed in potato cultivars (Agria and Lady Olympia) via Agrobacterium-mediated transformation. The molecular analysis confirmed gene integration and expression of the introduced genes in transgenic plants. The insecticidal effects of incorporated genes in transgenic plants were assessed against 1st, 2nd, 3rd, and 4th instar potato tuber moth (PTM) larvae. The transgenic plants endured significantly high mortalities (100%) of larval stages of PTM within 72 h. Our results show that these transgenic potato plants have the potential to control populations of PTM and are also useful tools in managing PTM that would ultimately reduce the dependency on conventional chemical pesticides with potentially less or minimal hazards. These lines can also serve as an excellent source of germplasm for potato breeding program.

Identification of entomopathogenic nematodes in Hainan Province, China and their efficacy against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)

The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a notorious migratory pest native to tropical and subtropical America. It invaded China in 2018 and can reproduce annually in Hainan Province. Entomopathogenic nematodes (EPNs) have gained interest as potential bioagent due to as an alternative to conventional pesticides are EPNs. We isolated 19 EPNs out of 155 soil samples using the Galleria-baiting method. This was the first comprehensive survey of EPNs in Hainan Province. Phylogenetic analyses of the ITS and D2D3 expansion region of the 28S rDNA gene were performed, and 19 strains belonging to Steinernema aciari, Steinernema sp., Heterorhabditis sp., Oscheius sp., Oscheius myriophilus and O. amsactae were identified. It was shown that S. aciari 22,000 caused 100% and 96% mortality to the third and sixth instar larvae of S. frugiperda, respectively. When the pupae of S. frugiperda were exposed to S. aciari 22,000, the pupae died after emergence. Our study suggests S. aciari 22,000 is a promising indigenous biocontrol agent against S. frugiperda in the future. These findings underscore the importance of continued investigation into the potential of indigenous EPNs for sustainable management strategies of S. frugiperda in agricultural areas.

Improving groundwater vulnerability assessment in structurally controlled hard rock aquifer: insight from lineament density and land use/land cover pattern.

A comprehensive seasonal assessment of groundwater vulnerability was conducted in the weathered hard rock aquifer of the upper Swarnrekha watershed in Ranchi district, India. Lineament density (Ld) and land use/land cover (LULC) were integrated into the conventional DRASTIC and Pesticide DRASTIC (P-DRASTIC) models and were extensively compared with six modified models, viz. DRASTIC-Ld, DRASTIC-Lu, DRASTIC-LdLu, P-DRASTIC-Ld, P-DRASTIC-Lu, and P-DRASTIC-LdLu, to identify the most optimal model for vulnerability mapping in hard rock terrain of the region. Findings were geochemically validated using NO3- concentrations of 68 wells during pre-monsoon (Pre-M) and post-monsoon (Post-M) 2022. Irrespective of the applied model, groundwater vulnerability shows significant seasonal variation, with > 45% of the region classified as high to very high vulnerability in the pre-M, increasing to ̴67% in post-M season, highlighting the importance of seasonal vulnerability assessments. Agriculture and industries' dominant southern region showed higher vulnerability, followed by regions with high Ld and thin weathered zone. Incorporating Ld and LULC parameters into DRASTIC-LdLu and P-DRASTIC-LdLu models increases the 'Very High' vulnerability zones to 17.4% and 17.6% for pre-M and 29.4% and 27.9% for post-M, respectively. Similarly, 'High' vulnerable zones increase from 32.5% and 25% in pre-M to 33.8% and 35.3% in post-M for respective models. Model output comparisons suggest that modified DRASTIC-LdLu and P-DRASTIC-LdLu perform better, with accurate estimations of 83.8% and 89.7% for pre-M and post-M, respectively. However, results of geochemical validation suggest that among all the applied modified models, DRASTIC-LdLu performs best, with accurate estimations of 34.4% and 20.6% for pre-M and post-M, respectively.

Expression and Functional Characterization of Oryzacystatin II Protein from Oryza sativa L. Indica Rice and Its Potential Role as a Bioinsecticide Against Major Insects of Rice.

Rice (Oryza sativaL.) is a crucial staple food crop globally, facing significant challenges from various pests that affect crop productivity and quality. Conventional pesticide usage has limitations, necessitating the development of sustainable pest management strategies. This study focuses on the expression, purification, and functional characterization of Oryzacystatin II (OC-II), a protein derived from O. sativaL. Indica rice, with the intent to evaluate its potential as a bioinsecticide against rice pests. The OC-II gene was expressed and purified, and purification confirmed its molecular weight (∼12 kDa) and protein sequence through LC-MS/MS analysis and Western blotting. The IC50 value of OC-II was calculated as 0.06 μM, and the inhibition was identified as a competitive inhibition. The protein exhibited efficient control of both pests at the nymph and adult stages, with lower probing marks observed on treated plants. The inhibition of cathepsin B enzyme activity in insects further confirmed the bioactivity of the OC-II protein. Molecular docking and molecular dynamics simulations provided insights into the interaction between the OC-II protein and cathepsin enzymes reported in BPH and WBPH. Further investigations can focus on optimizing production methods and exploring the specificity and efficacy of the OC-II protein against other crop pests to enhance its practical applications.

Binding of green tea epigallocatechin gallate to the arginine kinase active site from the brown recluse spider (Loxosceles laeta): A potential synergist to chemical pesticides

Loxosceles spp. spiders can cause serious public health issues. Chemical control is commonly used, leading to health and environmental problems. Identifying molecular targets and using them with natural compounds can help develop safer and eco-friendlier biopesticides. We studied the kinetics and predicted structural characteristics of arginine kinase (EC 2.7.3.3) from Loxosceles laeta (LlAK), a key enzyme in the energy metabolism of these organisms. Additionally, we explored (−)-epigallocatechin gallate (EGCG), a green tea flavonoid, as a potential lead compound for the LlAK active site through fluorescence and in silico analysis, such as molecular docking and molecular dynamics (MD) simulation and MM/PBSA analyses. The results indicate that LlAK is a highly efficient enzyme (KmArg 0.14 mM, KmATP 0.98 mM, kcat 93 s−1, kcat/KmArg 630 s−1 mM−1, kcat/KmATP 94 s−1 mM−1), which correlates with its structure similarity to others AKs (such as Litopenaeus vannamei, Polybetes pythagoricus, and Rhipicephalus sanguineus) and might be related to its important function in the spider's energetic metabolism. Furthermore, the MD and MM/PBSA analysis suggests that EGCG interacted with LlAK, specifically at ATP/ADP binding site (RMSD <1 nm) and its interaction is energetically favored for its binding stability (−40 to −15 kcal/mol). Moreover, these results are supported by fluorescence quenching analysis (Kd 58.3 μM and Ka 1.71 × 104 M-1). In this context, LlAK is a promising target for the chemical control of L. laeta, and EGCG could be used in combination with conventional pesticides to manage the population of Loxosceles species in urban areas.

Forever Pesticides: A Growing Source of PFAS Contamination in the Environment.

Environmental contamination by fluorinated chemicals, in particular chemicals from the per- and polyfluoroalkyl substances (PFAS) class, has raised concerns around the globe because of documented adverse impacts on human health, wildlife, and ecosystem quality. Recent studies have indicated that pesticide products may contain a variety of chemicals that meet the PFAS definition, including the active pesticide ingredients themselves. Given that pesticides are some of the most widely distributed pollutants across the world, the legacy impacts of PFAS addition into pesticide products could be widespread and have wide-ranging implications on agriculture and food and water contamination, as well as the presence of PFAS in rural environments. The purpose of this commentary is to explore different ways that PFAS can be introduced into pesticide products, the extent of PFAS contamination of pesticide products, and the implications this could have for human and environmental health. We submitted multiple public records requests to state and federal agencies in the United States and Canada and extracted relevant data from those records. We also compiled data from publicly accessible databases for our analyses. We found that the biggest contributor to PFAS in pesticide products was active ingredients and their degradates. Nearly a quarter of all US conventional pesticide active ingredients were organofluorines and 14% were PFAS, and for active ingredients approved in the last 10 y, this had increased to 61% organofluorines and 30% PFAS. Another major contributing source was through PFAS leaching from fluorinated containers into pesticide products. Fluorination of adjuvant products and "inert" ingredients appeared to be limited, although this represents a major knowledge gap. We explored aspects of immunotoxicity, persistence, water contamination, and total fluorine load in the environment and conclude that the recent trend of using fluorinated active ingredients in pesticides may be having effects on chemical toxicity and persistence that are not given adequate oversight in the United States. We recommend a more stringent risk assessment approach for fluorinated pesticides, transparent disclosure of "inert" ingredients on pesticide labels, a complete phase-out of post-mold fluorination of plastic containers, and greater monitoring in the United States. https://doi.org/10.1289/EHP13954.

The Role of Agrotechnology in Pest Management: Assessing the Effectiveness of Biopesticides, Integrated Pest Management, and Genetic Engineering

This qualitative study investigates the role of agrotechnology in pest management by assessing the effectiveness of biopesticides, integrated pest management (IPM), and genetic engineering. Through an extensive review of existing literature and case studies, the research aims to elucidate how these technological advancements contribute to sustainable agricultural practices and effective pest control. Biopesticides, derived from natural materials such as microorganisms, plants, and certain minerals, are highlighted as a key component in modern pest management. The study finds that biopesticides offer an environmentally friendly alternative to conventional chemical pesticides, reducing the ecological impact and the risk of pesticide resistance. They are effective against a broad spectrum of pests while being safe for non-target species, including humans and beneficial insects. The research underscores the importance of developing and optimizing biopesticide formulations to enhance their efficacy and acceptance among farmers. In conclusion, the study suggests that the integration of biopesticides, IPM, and genetic engineering in pest management strategies can lead to more sustainable and effective agricultural practices. It advocates for continued research and collaboration among scientists, policymakers, and farmers to develop and implement these technologies responsibly. Future research should explore the long-term impacts of these technologies on agricultural ecosystems and their potential to adapt to changing environmental conditions.

Biomass-Derived, Target Specific, and Ecologically Safer Insecticide Active Ingredients.

With the continuous increase in food production to support the growing population, ensuring agricultural sustainability using crop-protecting agents, such as pesticides, is vital. Conventional pesticides pose significant environmental risks, prompting the need for eco-friendly alternatives. This study reports the synthesis of new amide-based insecticidal active ingredients from biomass-derived monomers, specifically furfural and vanillin. The process involves reductive amination followed by carbonylation. The synthesis of the furfural-based carbamate yield reaches a cumulative 88 %, with catalysts Rh/Al2O3 and La(OTf)3 being recyclable at each stage. Insecticidal activity assessments reveal that the furfural carbamate exhibits competitive performance, achieving an LC50 of 254.22 μg/cm2, compared to 251.25 μg/cm2 for carbofuran. Ecotoxicity predictions indicate significantly lower toxicity levels toward non-target aquatic and terrestrial species. The importance of the low octanol-water partition coefficient of the biobased carbamate, attributed to the oxygen heteroatom and electron density of the furan ring, is discussed in detail. Building on these promising results, the synthesis strategy was extended to six other biobased aldehydes, resulting in a diverse portfolio of biomass-derived carbamates. A techno-economic analysis reveals a minimum selling price of 11.1 $/kg, only half that of comparable carbamates, demonstrating the economic viability of these new biobased insecticides.

The use of combination plant growth promoting rhizobacteria to control chili leaf curl disease in the field

Plant growth-promoting rhizobacteria (PGPR) is a promising technology for controlling viral diseases, including pepper yellow leaf curl disease (PYLCD) of chili pepper caused by Begomovirus infection. The objectives of this research were to investigate the effectiveness of PGPR containing Pseudomonas fluorescens PF1 and Bacillus polymyxa BG25, as well as their combination with other protective agents, to control PYLCD under field conditions in an endemic region. The treatments consisted of a single application of PGPR (a mixture of P. fluorescens PF1 and B. polymyxa BG25), guano tea, endophytic fungus H5, and neem oil; combination of PGPR with guano tea, endophytic fungus H5, and neem oil; conventional pesticide that relies on synthetic chemical insecticide sprayed weekly; and untreated plots. The experiment was arranged in a randomized block design with four replications. Treatment with PGPR alone was able to delay disease onset by 2.25 weeks, but it caused only a slight reduction in disease incidence. The combination of PGPR + guano tea and PGPR + endophyte H5 provided the best results in controlling PYLCD. The combination of PGPR + guano tea and PGPR + endophyte H5 delayed disease onset by 2.75 weeks and 3.25 weeks, respectively, and reduced disease incidence with effectiveness rates of 52.72% and 52.08%, respectively. These two treatment combinations gave the best performance for plant growth and yield.

Using predatory species and entomopathogenic fungi as alternatives to chemical pesticides in green bean field

BackgroundGreen bean, Phaseolus vulgaris L. (Fam.: Leguminosae) is a widely consumed grain legume prized for its edible seeds and pods. It is susceptible to infestations with various pests as insects and mites throughout the growing season. In this study, the efficacy of the predatory species, Chrysoperla carnea (Stephens), Phytoseiulus persimilis Athias-Henriot and the entomopathogenic fungus (EPF) Metarhizium anisopliae (Hypocreales: Clavicipitaceae), as well as conventional pesticides, Mospilan and Vertimec, were evaluated against the most important pests, mainly the whitefly, Bemisia tabaci (Genn.) and the two-spotted spider mite, Tetranychus urticae Koch, infesting the green beans cultivated at two locations Giza and El-Menoufia Governorates in Egypt.ResultsThe findings demonstrate that treatments using C. carnea and M. anisopliae effectively reduced the whitefly population, while pesticide treatments were comparatively less effective. In the Giza plots, at the end of the experiments, the use of both M. anisopliae and C. carnea showed high reductions in whitefly population (85.57 and 84.87%), respectively, while in El-Menoufia, C. carnea (97.74%) was the most effective treatment followed by M. anisopliae (90.32%). Pesticide treatment in this case yielded a reduction rate of (22.76 and 59.67%) in Giza and El-Menoufia plots, respectively. However, for spider mite control, P. persimilis proved to be the most effective treatment in Giza and El-Menoufia plots, reducing the spider mite population to 98.44 and 96.14%, respectively. Metarhizium anisopliae treatment also displayed moderate effectiveness, with reduction rates of 75.62 and 75.37% in Giza and El-Menoufia plots, respectively. In comparison, pesticide treatment showed low effectiveness, with reduction rates of only 23.92 and 53.16% in the two locations, respectively.ConclusionApplications of the predator, C. carnea and the EPF, M. anisopliae were highly effective in reducing the population of whitefly, while the predator mite P. persimilis proved to be the most effective for controlling the spider mites. Overall, the study suggests that biocontrol agents, such as the predators and the EPF, can be considered as alternatives to synthetic chemical pesticides for controlling pests infesting green beans.

Virulence and proteomic responses of Metarhizium anisopliae against Aedes albopictus larvae

The tropical climate in Malaysia provides an ideal environment for the rapid proliferation of Aedes mosquitoes, notably Aedes aegypti and Aedes albopictus, prominent vectors of dengue fever. Alarmingly, these species are increasingly developing resistance to conventional pesticides. This study aimed to evaluate the efficacy of Metarhizium anisopliae isolate HSAH5 spores, specifically on conidia (CO) and blastospores (BL), against Ae. albopictus larvae. The study centered on evaluating their pathogenic effects and the resultant changes in protein expression. Spore suspensions with varying concentrations were prepared for larvicidal bioassays, and protein expressions were analysed using liquid chromatography-mass spectrometry. Subsequently, protein annotation and network analysis were conducted to elucidate infection mechanisms and the proteomic response. Based on the lethal concentrations and time frames, CO exhibited faster larval mortality than BL at lower concentrations. Despite this, both spore types demonstrated comparable overall pathogenic effects. Results from the proteomic profiling revealed 150 proteins with varied expressions following exposure to Ae. albopictus extract, shedding light on distinct infection strategies between the spores. Gene Ontology enrichment and network analysis illustrated the diverse metabolic adaptations of M. anisopliae and interactions with mosquito larvae. This highlighted the complexity of host-pathogen dynamics and the significance of biosynthetic processes, energy storage, and cellular interaction pathways in disease progression. The BL network, consisting 80 proteins and 74 connections, demonstrates the intricate fungal mechanisms triggered by host stimuli. Conversely, the CO network, though smaller, displayed notable interconnectivity and concentrated involvement at the cell periphery, suggesting a deliberate strategy for initial host contact. This study offers valuable insights into proteome dynamics of M. anisopliae's BL and CO for managing mosquito populations and combating disease transmission, thereby significantly advancing public health and environmental conservation efforts.

Carrier-free self-assembled nanoparticles based on prochloraz and fenhexamid for reducing toxicity to aquatic organism

Nanoformulations of pesticides are an effective way to increase utilization efficiency and alleviate the adverse impacts on the environments caused by conventional pesticide formulations. However, the complex preparation process, high cost, and potential environmental risk of nanocarriers severely restricted practical applications of carrier-based pesticide nanoformulations in agriculture. Herein, carrier-free self-assembled nanoparticles (FHA-PRO NPs) based on fenhexamid (FHA) and prochloraz (PRO) were developed by a facile co-assembly strategy to improve utilization efficiency and reduce toxicity to aquatic organism of pesticides. The results showed that noncovalent interactions between negatively charged FHA and positively charged PRO led to core-shell structured nanoparticles arranged in an orderly manner dispersing in aqueous solution with a diameter of 256 nm. The prepared FHA-PRO NPs showed a typical pH-responsive release profile and exhibited excellent physicochemical properties including low surface tension and high max retention. The photostability of FHA-PRO NPs was improved 2.4 times compared with free PRO. The FHA-PRO NPs displayed superior fungicidal activity against Sclerotinia sclerotiorum and Botrytis cinerea and longer duration against Sclerotinia sclerotiorum on potted rapeseed plants. Additionally, the FHA-PRO NPs reduced the acute toxicity of PRO to zebrafish significantly. Therefore, this work provided a promising strategy to develop nanoformulations of pesticides with stimuli-responsive controlled release characteristics for precise pesticide delivery.

Antimicrobial Effects of Nitric Oxide against Plant Pathogens.

Pathogen infection represents the greatest challenge to agricultural crop production, resulting in significant economic loss. Conventional pesticides are used to control such infection but can result in antimicrobial resistance and detrimental effects on the plant, environment, and human health. Due to nitric oxide's (NO) endogenous roles in plant immune responses, treatment with exogenous NO represents an attractive nonpesticide approach for eradicating plant pathogens. In this work, the antimicrobial activity of small-molecule NO donors of varying NO-release kinetics was evaluated against Pseudomonas syringae and Botrytis cinerea, two prevalent plant pathogens. Intermediate NO-release kinetics proved to be most effective at eradicating these pathogens in vitro. A selected NO donor (methyl tris diazeniumdiolate; MD3) was capable of treating both bacterial infection of plant leaves and fungal infection of tomato fruit without exerting toxicity to earthworms. Taken together, these results demonstrate the potential for utilizing NO as a broad-spectrum, environmentally safe pesticide and may guide development of other NO donors for such application.