Synthetic Pesticides Research Articles

Advancing Sustainable Agriculture: A Comprehensive Review of Organic Farming Practices and Environmental Impact

Organic farming, characterized by the exclusion of synthetic fertilizers and chemical pesticides, represents a sustainable approach to agriculture. This study investigates the impact of organic farming practices on soil health, focusing on the proliferation and activity of soil microorganisms. Natural fertilizers such as farmyard manure, poultry litter, composts, green manures, and oil-free cakes were utilized to enhance soil fertility. The research reveals that these practices significantly improve soil health by fostering a robust microbiome, which is essential to the cycling of nutrients and overall health of the soil vitality. The safety and nutritional benefits of organic food products were also evaluated. Comparative analysis with conventionally grown foods indicates that organic produce contains lower levels of harmful residues such as pesticides, nitrates, metals, and antibiotics. This reduction in contaminants mitigates potential risks to human health associated with conventional farming practices. Furthermore, organic foods are found to be richer in essential nutrients, vitamins, and antioxidants, thereby offering superior nutritional value. The economic implications of organic farming were explored, highlighting its potential to enhance the economic viability of small-scale farmers. With increasing consumer awareness and demand for organic products, farmers practicing organic methods can command higher prices for their produce, thereby improving their economic sustainability and resilience. In conclusion, organic farming emerges as an environmentally friendly and economically viable alternative to conventional agriculture. By promoting soil health, reducing chemical residues in food, and meeting consumer demand for nutritious products, organic farming offers a pathway towards sustainable agricultural practices.

Landscape features support natural pest control and farm income when pesticide application is reduced

Future trajectories of agricultural productivity need to incorporate environmental targets, including the reduction of pesticides use. Landscape features supporting natural pest control (LF-NPC) offer a nature-based solution that can serve as a partial substitute for synthetic pesticides, thereby supporting future productivity levels. Here, we introduce a novel approach to quantify the contribution of LF-NPC to agricultural yields and its associated economic value to crop production in a broad-scale context. Using the European Union as case study, we combine granular farm-level data, a spatially explicit map of LF-NPC potential, and a regional agro-economic supply and market model. The results reveal that farms located in areas characterized by higher LF-NPC potential experience lower productivity losses in a context of reduced synthetic pesticides use. Our analysis suggests that LF-NPC reduces yield gaps on average by four percentage points, and increases income by a similar magnitude. These results highlight the significance of LF-NPC for agricultural production and income, and provide a valuable reference point for farmers and policymakers aiming to successfully invest in landscape features to achieve pesticides reduction targets.

Effect of Organic and Inorganic Sources of Nitrogen on Growth Parameter and Yield Attribute of Wheat in Inceptisolof Eastern Uttar Pradesh, India

The insufficient availability and escalating expenses of fertilizers present significant constraints to crop production, exacerbating the growing disparity between nutrient demand and supply. The overreliance on agrochemicals like synthetic fertilizers, pesticides, herbicides, and fungicides not only endangers human health but also degrades soil quality and environmental integrity. This study examined the impact of applying recommended doses of fertilisers (RDF) in conjunction with organic amendments in a pot experiment carried out throughout the 2020–2021 wheat growing season. Significant improvements were found for the following wheat plant attributes: straw and grain yields; height; greenness index; spike count; spike length; and weight of 1000 seeds. The treatment utilizing 50% RDF and 50% poultry manure (T5) demonstrated the most pronounced improvements across these parameters. These findings highlight integrated nutrient management's crucial importance as a modern agricultural requirement.

Effect of varying levels of achichi (Cannabis sativum L.) seed oil extract in the inhibition of bacteria spot disease of scotch pepper (Capsicum annum L.)

Negative food safety reports over the use of synthetic pesticides in controlling bacteria disease of pepper caused by Xanthomonas campestris pv is increasing in Nigeria, hence the need for friendly options. An experiment was carried out at the Teaching and Research Farm of Rufus Giwa Polytechnic, Owo, located on latitude 70 12N and longitude 50 35E at 350m above sea levels, to evaluate the effect of varying levels of achichi (Cannabis sativum L.) seed oil extract in the inhibition of bacteria spot disease of scotch pepper (Capsicum annum L.). Treatments include; Positive control (Synthetic Rindomil gold), Negative control (distill water), 2 ml ASO (Achichi seed oil), and 4ml ASO (Achichi seed oil) which were randomly distributed into plots, arranged in a Randomized Complete Block Design (RCBD). Results showed that the application of ASO had bactericidal inhibition potential against the bacteria spot diseases comparable to the synthetic ridomil powder. Application of between 2 – 4 ml / 1 liter of water of ASO was found to significantly influence the general performance of sprayed pepper in the study area. Further investigation should be carried out to determine the right volume between the ranges of 2 ml – 4 ml of ASO that can effectively control the bacteria spot disease in the study area.

PENGARUH KONSENTRASI EKSTRAK DAUN KELOR (Moringa oleifera L.) TERHADAP MORTALITAS Sitophilus zeamais Motsch.

Corn is the strategic commodity in Indonesia. The quality of many domestic corn does not meet feed factory standards. High yield losses icause of damage due to warehouse pests. Sitophilus zeamais Motsch or powder beetle is a warehouse pest that causes seeds to become hollow, break quickly and disintegrate into flour. Sitophilus zeamais Motsch pest control still relies on synthetic pesticides. The use of synthetic pesticides will cause various negative impacts such as pest resistance, residue, resurgencies, high costs and environmental pollution. One alternative for controlling Sitophilus zeamais Motsch is to use natural ingredients, namely Moringa. Moringa leaves contain phenol, hydroquinone, flavonoids, steroids, triterpenoids, tannins, alkaloids and saponins. The experiment began by drying 10 grams of Moringa leaves. then puree using a blender and continue with maceration. 200, 400, 600, 800, and 1000 mg of Moringa leaf powder were dissolved in 1 L of distilled water solution and left for 24 hours. After 24 hours, the solution was filtered 3 times so that all the substances contained in the Moringa leaves are extracted. The insecticide was tested by observing the number of S. zeamais pests that died when given Moringa leaf extract. The mortality data that was obtained was analyzed using ANOVA, if there was a real effect then continued using the 5% DMRT test. Determination of LC50 using a probit test. Moringa extract can function as a vegetable insecticide for S.zeamais. The higher concentration of Moringa leaf extract can increase the mortality of S.zeamais

Molecular Characterization Reveals Biodiversity and Biopotential of Rhizobacterial Isolates of Bacillus Spp

Bacillus species appearas the most attractive plant growth-promoting rhizobacteria (PGPR) and alternative to synthetic chemical pesticides. The present study examined the antagonistic potential of spore forming-Bacilli isolated from organic farm soil samples of Allahabad, India. Eighty-seven Bacillus strains were isolated and characterized based on their morphological, plant growth promoting traits and molecular characteristics. The diversity analysis used 16S-rDNA, BOX-element, and enterobacterial repetitive intergenic consensus. Two strains, PR30 and PR32, later identified as Bacillus sp., exhibited potent in vitro antagonistic activity against Ralstonia solanaceorum. These isolates produced copious amounts of multiple PGP traits, such as indole-3-acetic acid (40.0 and 54.5 μg/mL), phosphate solubilization index (PSI) (4.4 and 5.3), ammonia, siderophore (3 and 4 cm), and 1-aminocyclopropane-1-carboxylate deaminase (8.1and 9.2 μM/mg//h) and hydrogen cyanide. These isolates were subjected to the antibiotic sensitivity test. The two potent isolates based on the higher antagonistic and the best plant growth-promoting ability were selected for plant growth-promoting response studies in tomatoe, broccoli, and chickpea. In the pot study, Bacillus subtilis (PR30 and PR31) showed significant improvement in seed germination (27–34%), root length (20–50%), shoot length (20–40%), vigor index (50–75%), carotenoid content (0.543–1.733), and lycopene content (2.333–2.646 mg/100 g) in tomato, broccoli, and chickpea. The present study demonstrated the production of multiple plant growth-promoting traits by the isolates and their potential as effective bioinoculants for plant growth promotion and biocontrol of phytopathogens.

High-energy emulsification of Allium sativum essential oil boosts insecticidal activity against Planococcus citri with no risk to honeybees

AbstractThe ecotoxicological consequences of synthetic pesticides have encouraged stakeholders to search for eco-friendly pest control tools, like essential oils (EOs). Nano-delivery systems (nanoparticles and nano-emulsions) seem ideal for developing EO-based biopesticides, although production processes should be standardized and implemented. In this study, nano-emulsions loaded with a high amount of Allium sativum L. EO (15%) were developed using different mixed bottom-up/top-down processes. Garlic EO was chemically analyzed by gas chromatography-mass spectrometry (GC-MS) and formulations were physically characterized using Dynamic Light Scattering (DLS) apparatus. The insecticidal activity against Planococcus citri Risso (Hemiptera: Pseudococcidae) and selectivity toward Apis mellifera L. (Hymenoptera: Apidae) worker bees was evaluated. Garlic EO was mainly composed of sulphur components (96.3%), with diallyl disulphide and diallyl trisulphide as the most abundant compounds (37.26% and 28.15%, respectively). Top-down processes could produce stable nano-emulsions with droplet size in the nanometric range (< 200nm) and good polydispersity index (PDI < 0.2). In contrast, the bottom-up emulsion was unstable, and its droplet size was around 500nm after 24 hours. High-energy emulsification processes significantly increased the residual toxicity of garlic EO against 3rd instar P. citri nymphs, whereas the developed formulations were harmless to A. mellifera workers in topical application. This study confirmed that the production process significantly affected the physical properties and efficacy against target pests. The lack of adverse impact on honeybees denotated the potential of these formulations as bioinsecticides in organic and/or IPM programs, although further extended ecotoxicological studies are necessary.

GC-MS Analysis and Evaluation of Essential Oils as Volatile Biopesticides: Assessing Their Acaricidal Potential against Varroa destructor

Honey bees are crucial for ecosystem pollination and honey production, yet the Varroa destructor mite hinders their productivity and health. Efforts to manage Varroa mites with synthetic pesticides have had limited success, highlighting the need for naturally derived acaricides as a primary option. However, the acaricidal efficacy of essential oils from Salvia officinalis L. (sage), Cannabis sativa (hemp), and Laurus nobilis (laurel) remains to be fully understood. This study aims to investigate the acaricidal efficacy of these three essential oils at varying concentrations and their impact on honey production, focusing on the efficient reduction in Varroa mites. The sugar roll method was employed to assess Varroa mite infestation levels, while GC-MS analysis was utilized to verify the composition of the essential oils. Honey production measurements were also performed. The efficacy rates (%) at concentrations of 15%, 10%, and 5% for hemp oil were 95.4% ± 0.30%, 85.71% ± 0.85%, and 64.48% ± 0.26%, respectively; for sage oil, they were 81.08% ± 0.57%, 69.42% ± 1.72%, and 50.35% ± 0.70%; and for laurel oil, they were 68.96% ± 0.34%, 54.66% ± 0.37%, and 33.58% ± 0.30%, respectively. Key compounds identified include trans-caryophyllene, α-pinene, and viridiflorol in hemp oil; myrcene, limonene, and β-caryophyllene in sage oil; and phytol, β-myrcene, and n-heneicosane in laurel oil. The overall findings indicate that hemp oil is highly effective in controlling Varroa mites. However, further research is needed to evaluate its potential side effects on bees to ensure its sustainability and safety.

Optimizing Sustainable Agricultural Practices: A Case Study of Integrated Pest Management Strategies in Farming

An essential component of sustainable agriculture is integrated pest management (IPM), which offers a thorough and ecologically friendly method of insect control. This strategy blends several strategies to discourage the overuse of synthetic pesticides and encourages the prudent application of control, monitoring, and control techniques for efficient pest management. Here, we look at the combination of biological, chemical, cultural, and mechanical applications while examining the fundamental ideas and features of integrated pest management. The migration of resistant species, cultural customs, and the coexistence of infections and predators are important elements. The environmental benefits of integrated pest management (IPM), including the decrease in pesticide use and head poverty, are aligned with the economic benefits of IPM, such as cost savings and long-term sustainability. KEYWORDS -Agriculture, pests, predators, parasitoids, biological control, pesticides, and organic farming.

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.

Exploring the synergistic toxicity of synthetic pesticides and their impact on development and behavior of Honeybee (Apis mellifera L.)

Exploring the synergistic toxicity of synthetic pesticides and their impact on development and behavior of Honeybee (Apis mellifera L.)

Biosynthesis and characterization of selenium and silver nanoparticles using Trichoderma viride filtrate and their impact on Culex pipiens

Abstract Some of the significant globally prevalent vector-borne illnesses are caused by Culex pipiens. Synthetic pesticides have been widely utilized to eradicate C. pipiens, which has led to a number of health risks for people, insect resistance, and environmental contamination. Alternative strategies are therefore vitally needed. In the current investigation, the Trichoderma viride fungal culture filtrate was used to create selenium and silver nanoparticles (SeNPs and AgNPs, respectively) and test them on C. pipiens larvae in their fourth instar stage. The death rate increased significantly when SeNP and AgNP concentrations increased, according to the results. SeNPs and AgNPs significantly affected the developmental and detoxification enzymes in fourth instar larvae of C. pipiens at 24 h after being treated with the sublethal concentration of the tested NPs. As a result of their insecticidal effect on C. pipiens larvae, SeNPs and AgNPs are considered effective and promising larvicidal agents.

The potential therapeutic value of terpenes

Terpenes form part of a huge and diverse class of naturally occurring and volatile secondary metabolites produced by many plants, fruits, animals, insects, and other organisms. They are the largest group of naturally occurring metabolites, with over 55,000 types of terpenes produced by plants alone, primarily as essential oils. In humans, they contain significant biological properties such as antifungal, antiviral, antimicrobial, anti-inflammatory, antiparasitic, antihyperglycemic, anti-cancer, and analgesic agents. In plants, terpenes also play significant roles in defensive mechanisms against herbivores and invasive plants, disease resistance, chemical signaling and communication between plants, protection against photo-oxidation, plant-environment mediation, thermo-protection, and the attraction of pollinators. In addition, terpenes are responsible for a plant’s scent, taste, flavor, and pigmentation, leading to their commercial use as fragrances and food dyes. Terpenes are also used in the production of synthetic polymers, natural rubbers (polyisoprene), organic solvents, varnishes, inks, adhesives, cleaning products, biofuels, pesticides, and food and drink products. For these reasons, terpenes have significant value in modern medicine, pharmacy, nutraceuticals, cosmetics, and other industries.

Exploring the Potential of Myrcia Genus Essential Oils: A Review of Biological Activities and Recent Advances.

The present study provides a comprehensive analysis of the chemical composition of essential oils from species of the Myrcia genus and their applications. The compiled results highlight the chemical diversity and biological activities of these oils, emphasizing their potential importance for various therapeutic and industrial applications. The findings reveal that Myrcia essential oils present a variety of bioactive compounds, such as monoterpenes and sesquiterpenes, which demonstrate antimicrobial activities against a range of microorganisms, including Gram-positive and Gram-negative bacteria, as well as yeasts. Furthermore, this study highlights the phytotoxic activity of these oils, indicating their potential for weed control. The results also point to the insecticidal potential of Myrcia essential oils against a range of pests, showing their viability as an alternative to synthetic pesticides. Additionally, species of the genus Myrcia have demonstrated promising hypoglycemic effects, suggesting their potential in diabetes treatment. This comprehensive synthesis represents a significant advancement in understanding Myrcia essential oils, highlighting their chemical diversity and wide range of biological activities. However, the need for further research is emphasized to fully explore the therapeutic and industrial potential of these oils, including the identification of new compounds, understanding of their mechanisms of action, and evaluation of safety and efficacy in different contexts.

Microbial consortium formulation in liquid organic fertilizer for managing bacterial leaf blight (Xanthomonas oryzae pv. oryzae), rice blast (Pyricularia oryzae), and enhancing rice productivity

Abstract. Nurcahyanti SD, Masnilah R, Budiman SA, Tanzil AI, Nurdika AAH. 2024. Microbial consortium formulation in liquid organic fertilizer for managing bacterial leaf blight (Xanthomonas oryzae pv. oryzae), rice blast (Pyricularia oryzae), and enhancing rice productivity. Biodiversitas 25: 2208-2220. The productivity of rice is significantly influenced by soil fertility and plant diseases as limiting factors. The overreliance on synthetic fertilizers and pesticides in rice cultivation has led to declining land quality. We propose the utilization of Liquid Organic Fertilizers (LOF) enriched with beneficial microbes as a sustainable solution to maintain soil fertility and protect plants from pathogens. Our research specifically focuses on the formulation of LOF enriched with the microbial consortium to enhance rice productivity and suppress bacterial leaf blight (Xanthomonas oryzae pv. oryzae), and rice blast (Pyricularia oryzae) diseases. The three LOF treatments were formulated from vegetable and fruit waste (FV), Rice Straw (RS), and Cattle Manure (CM) with a microbial consortium consisting of Pseudomonas putida Pf10, Bacillus subtilis JB12, and Trichoderma sp. The results showed that the LOF from the three materials is suitable for the growth of the microbial consortium with a population of 104-109 CFU/mL, has macro-micronutrient content, pH at 6.5-6.8, and C-organic to support plant growth. The applications of the three types of LOF were able to suppress the severity of bacterial leaf blight by up to 21% and rice blast by 4% at eight weeks after inoculation. All LOF treatments are capable of enhancing the growth and production of rice. There were no significant differences in LOF materials for disease suppression, growth, and rice production.

Exploring the Efficacy of Four Essential Oils as Potential Insecticides against Thrips flavus

Plant essential oils are important alternatives in green integrated pest management. This study examined the chemical composition, bioactivity, and control efficacy of four Lamiaceae essential oils (EOs) against Thrips flavus Schrank in laboratory conditions with the goal of exploiting plant-derived insecticides to control Thrips flavus. The four EOs tested were marjoram oil (Origanum majorana L.), clary sage oil (Salvia sclarea L.), perilla leaf oil (Perilla frutescens (L.) Britt.), and spearmint oil (Mentha spicata L.). All these EOs exhibited a certain degree of insecticidal activity against Thrips flavus. The median lethal concentration (LC50) was determined after treatment by the leaf-dipping method in laboratory bioassays, and its values were 0.41 mg/mL for marjoram oil, 0.42 mg/mL for clary sage oil, 0.43 mg/mL for perilla leaf oil, and 0.54 mg/mL for spearmint oil. In the pot experiment, the number of dead insects was recorded at 1, 3, and 7 days post-application, and the control efficacy of EOs against Thrips flavus was calculated. The concentration of 900.00 g a.i.·hm−2 of spearmint oil was 100% lethal against Thrips flavus after treating potted plants for seven days. The Y-tube olfactometer method was used to test for the attraction or repellent response of EOs against Thrips flavus. The spearmint oil significantly attracted female adults in the olfactory test. Furthermore, gas chromatography–mass spectrometry (GC–MS) was used to examine the chemical composition of the EOs. Linalool (24.52%), isopropyl myristate (28.74%), (+)-limonene (32.44%), and (+)-carvone (70.3%) were their primary ingredients. The findings suggest that all four EOs are highly effective against Thrips flavus and may be a possible alternative in the management of Thrips flavus, especially when considering reducing the use of synthetic pesticides.

Phytochemical Volatiles as Potential Bionematicides with Safer Ecotoxicological Properties.

The management of plant-parasitic nematodes (PPNs) still relies on traditional nematicides that threaten the environment and human health. Novel solutions are urgently needed for PPN pest management that are effective while safeguarding non-target organisms. Volatile phytochemicals belong to a structurally diverse group of bioactive metabolites that are believed to hold safer environmental characteristics than synthetic pesticides. Nonetheless, not many studies have analysed the potential environmental benefits of shifting to these novel bionematicides. In the present study, 20 phytochemical volatiles with reported nematicidal activity were compared to traditional pesticides using specific parameters of environmental and human health safety available on applied online databases and predicted in silico through specialised software. Overall, the reviewed nematicidal phytochemicals were reportedly less toxic than synthetic nematicides. They were predicted to disperse to the air and soil environmental compartments and were reported to have a lower toxicity on aquatic organisms. On the contrary, the synthetic nematicides were reportedly toxic to aquatic organisms while showing a predicted high affinity to the water environmental compartment. As alternatives, β-keto or fatty acid derivatives, e.g., aliphatic alcohols or ketones, showed more adequate properties. This study highlights the importance of complementing studies on nematicidal activity with a risk assessment-based analysis to allow for a faster selection of nematicidal phytochemical volatiles and to leverage the development and implementation of bionematicides.

Lambda-Cyhalothrin induced behavioural, neurotoxic and oxidative stress on vertebrate model Danio rerio (Hamilton-Buchanan 1822).

λ-cyhalothrin, a synthetic type II pyrethroid, has become increasingly popular for control of aphids, butterfly larvae, and beetles, replacing other agricultural chemicals. As a result of which, residues of this synthetic pesticide are being reported across the globe in natural water, which poses a serious threat to aquatic life. Therefore, the present study was designed to understand the toxicity effects of λ-cyhalothrin on behaviour, oxidative stress and neurotoxicity in a vertebrate aquatic model, zebrafish (Danio rerio). The fish were exposed to 0.129, 0.194 and 0.388 µg/L corresponding to 5%, 10% and 20% of 96hLC50 (1.94 µg/L) for 28 days. Upon exposure to the highest concentration (0.388 µg/L), the test animal exhibited significant alterations in behavioural patterns like number of entries to the top zone (n), decrease in average speed (m/s) and decrease in time spent in top zone (s). Moreover, the shoaling test demonstrated a significant decrease (p < 0.05) in the relative time spent by the tested fish (%) near the stimulus fish. The change in behavioural alterations might be linked to a significant decrease (p < 0.05) in the brain acetylcholine esterase activity. Furthermore, the present study also illustrates oxidative stress exerted by λ-cyhalothrin through an increase in the production of reactive oxygen species, which is again clearly depicted by a significant increase (p < 0.05) in Superoxide dismutase, Catalase and Glutathione peroxidase activities. Overall, the present study systematically demonstrates the chronic effects of λ-cyhalothrin on adult fish behaviour and physiology, which will contribute to assessing the risks of λ-cyhalothrin to organismal health.

Prospects of indigenous fungi as novel biological control agents of thrips (Frankliniella occidentalis Pergande, 1895) on tomato (Solanum lycopersicum L.) in vivo

Tomato (Solanum lycopersicum L.) is an important horticultural crop in Kenya. Its production is constrained by many factors, among them arthropod pests and diseases. In response, farmers rely on synthetic pesticides, which lead to contamination of the produce, pest resistance and pollution of the environment hence there is need to identify safer, affordable alternatives. Biological control is considered safe, self-sustaining and cost effective. This study was aimed at determining the effectiveness of indigenous fungi in managing Western flower thrips Frankliniella occidentalis on tomato. Efficacy trials were conducted in farmer’s fields in Bungoma County, Kenya between March and November 2018. Treatments included fungal isolates Trichoderma harzianum, Gliocladium virens, Verticillium spp., Paeciliomyces victoriae and Fusarium oxysporum selected after in vitro screening. These were compared to commercial fungus Beauveria basssiana, a synthetic pesticide imidacloprid and untreated control. Treatments were replicated four times, arranged in a randomized complete block design. Data collected on population of thrips and the yield of tomatoes were subjected to Analysis of Variance (ANOVA). Means were separated using Student Newman-Keuls (SNK) test at p≤0.05. In the first season at Bukonoi, F. oxysporum significantly (p&lt;0.05) recorded the least (38.1) mean number of thrips compared to the untreated control (89.2). At Cheptais, F. oxysporum and T. harzianum treated plots significantly (p&lt;0.05) recorded the least mean number of thrips of 48.1 and 20.5 in the first and second season, respectively. Higher yields of 4.9 t ha-1 and 29.5 t ha-1 were obtained from plots treated with T. harzianum in the first and second season, respectively. The findings of this study demonstrated that F. oxysporum and T. harzianum have the potential to be developed as fungal biopesticides for management of thrips on tomato crop. However, large scale field trials are warranted to validate the effectiveness of these fungal isolates. Key words: Biopesticides, Frankliniella occidentalis, Fusarium oxysporum, Solanum lycopersicum, Trichoderma harzianum.

CHEMICAL COMPOSITION AND INSECTICIDAL EFFICACY OF VITEX NEGUNDO L. ESSENTIAL OIL AGAINST FALL ARMYWORM, SPODOPTERA FRUGIPERDA (J. E. SMITH)

The fall armyworm, Spodoptera frugiperda, is a key pest ofmaize crops in tropical and subtropical regions and has developed resistanceagainst synthetic pesticides and Bacillus thuringiensis toxins. Thus,the experiments were designed to evaluate the chemical analysis andinsecticidal efficacy of Vitex negundo against S. frugiperda.Chemical analysis of V. negundo essential oil revealed a total of 36compounds, and the oil contained more monoterpenes (68.16%) than sesquiterpenes(22.21%) and diterpenes (13.56%). For the ovicidal and insecticidal activities,the essential oil was found to be most effective, with a median lethalconcentration (LC50) value of 51.31 µL/mL and 0.29 L/larvae, respectively.Larval antifeedant and growth inhibitory activity of essential oil werepositively correlated (R2 = 0.9645) and (R2 = 0.9727) with oil concentrations,respectively. Therefore, the V. negundo essential oil can be used forthe development of bioinsecticides to control S. frugiperda, a highlyinvasive and polyphagous pest, which will replace chemical pesticides.