Search Results (184)

The global spread and incidence of microbial phytopathogens are expected to increase due to climate change and the intensification of international food trade, threatening crop productivity. While pesticides remain essential for managing disease severity, European regulations and initiatives, such as the Green Deal, have emphasized the urgent need to reduce their indiscriminate use, which has contributed to pest resistance, environmental contamination, and human health issues. Botanical pesticides, particularly flavonoids, represent promising complements to traditional pesticides because of their diverse composition of antimicrobial agents. Therefore, this review provides an overview of the antimicrobial potential of flavonoids for microbial phytopathogens, focusing on agricultural fungal pathogens and bacterial phytopathogens. The mechanisms of action by which flavonoids exert their pesticidal activity are detailed, along with structure–activity relationships, formulation, and market perspectives. The literature reveals that flavonoids possess strong potential against pre- and postharvest crop diseases caused by fungal and bacterial pathogens owing to their ability to exert multisite activity, although limited data is verified for antibacterial studies. However, their successful transition to the pesticide market requires field performance validation, formulation technologies, toxicological assessment, and regulatory harmonization. Full article

Achieving sustainable agriculture requires environmentally friendly alternatives to synthetic insecticides. Hence, this review seeks to evaluate the sustainable use of syringa as a botanical pesticide in small-scale farming systems. The review applied an integrated literature review framework to synthesize published work on Melia azedarach L. use in insect pest control. Peer-reviewed and grey literature were sourced from multiple databases and repositories using defined keywords. No lower time limit was applied, and literature coverage included published work up to 2026. After screening 159 records, 99 studies were retained and thematically grouped into eight areas: botanical description, distribution, biopesticides and their mode of action, botanical insecticides and their benefits, Melia. azedarach L. as a botanical insecticide, the limitations on the usage of plant-based extracts and the effects of different extraction methods on the efficacy of Melia azedarach L. extracts. A narrative synthesis highlighted key findings, contradictions, and knowledge gaps while noting potential biases, including English-only sources. Studies indicate that Melia azedarach L. exhibits multiple modes of action, including repellency, antifeedant activity, oviposition deterrence, growth inhibition, ovicidal and larvicidal effects, and suppression of adult emergence. Despite challenges such as variability in extract composition, limited field standardization, and short residual activity, Melia azedarach L. shows considerable potential as a sustainable component of integrated pest management for small-scale farming. Future research should focus on standardized extraction protocols, field validation, formulation development, and commercialization to enhance adoption. Full article

Botanical insecticides are increasingly being investigated as alternatives to synthetic pesticides for stored-grain protection. This review critically evaluates Aloe ferox Mill. as a candidate botanical insecticide with potential relevance to Sitophilus zeamais Motsch, the major stored-maize pest. The available evidence related to the phytochemistry, reported pesticidal activities, proposed mechanisms of action, safety, and research needs was synthesised. A. ferox possesses a variety of secondary metabolites like anthraquinones, flavonoids, phenolics, chromones, tannins, alkaloids, and saponins, some of which have been reported to possess insecticidal, repellent, antifeedant, or growth-regulatory activity in other biological systems. But there is currently no direct experimental proof of the effectiveness of A. ferox against S. zeamais. A large proportion of the evidence relevant to pesticides is from other Aloe species, other insect and arthropod pests, or from one component or phytochemical studied in a different biological system. The findings, therefore, offer a justification for further investigations, but do not provide evidence of efficacy. Future research should focus on bioassays that directly test dose–responses, phytochemical standardisation, mechanism validation, formulation development, grain quality and residue evaluation, safety evaluation, and validation using realistic storage conditions. Full article

Botanical gardens are highly heterogeneous plant systems characterized by high taxonomic diversity, with numerous plant taxa represented within confined areas, and complex ecological interactions that create unique challenges for pest management. Conventional IPM strategies, designed for simplified agroecosystems, often fail to address complex pest pressures in curated environments. Microbial biostimulants have emerged as promising components of sustainable IPM strategies by enhancing plant defense responses, improving stress resilience, and reducing reliance on chemical inputs. This review synthesizes current knowledge on microbial biostimulants, including plant growth-promoting rhizobacteria, arbuscular mycorrhizal fungi and endophytic microorganisms, in modulating plant defense against insect herbivores. These beneficial microbes enhance plant resistance through multiple mechanisms. They activate induced systemic resistance and modulate key phytohormones, including jasmonic acid, salicylic acid, and ethylene. Additionally, they regulate calcium-dependent and reactive oxygen species-mediated defenses. Microbially induced changes in plant secondary metabolites and volatile organic compounds further influence herbivore behavior and trophic interactions. Emphasis is placed on integrating microbial biostimulants into IPM frameworks tailored to botanical gardens. This highlights compatibility with biological control agents and reduced reliance on synthetic pesticides. Despite promising advances, challenges remain, including context-dependent efficacy, host specificity and limited long-term validation. Overall, microbial biostimulants offer a promising tool for enhancing IPM in biodiversity-rich botanical gardens, although further long-term validation is needed to fully assess their sustainability and effectiveness. Full article

Pest pressure is a major constraint on crop production in Sub-Saharan Africa, where smallholder farmers rely heavily on synthetic pesticides with potential environmental and health risks. Ecological pest management practices (EPMs) have been proposed as sustainable alternatives, although field-based evidence is limited. This study evaluated pest and natural-enemy responses to EPMs in a cabbage–garden pea rotation system over six years (2020–2025) in Central Kenya. Four treatments were assessed: homemade botanical extracts (Botanicals), coriander intercropping (Intercrop), botanical extracts combined with coriander intercropping (Botanicals + Intercrop), and a control. In cabbage, ecological treatments often recorded lower aphid and diamondback moth abundance and damage than the Control, although these patterns were not consistently significant. Aphid cumulative abundance ranged from an Area Under Disease Progress Curve (AUDPC) of 128.0 under the Control to 47.5 under Botanicals + Intercrop, while DBM abundance ranged from 68.5 to 20.0. In garden pea, aphid damage ranged from an AUDPC of 39.3 under Intercrop to 25.1 under Botanicals + Intercrop, while cutworm damage ranged from 56.3 under Botanicals to 14.8 under Intercrop. Significant treatment effects were detected for selected pest responses. Shannon diversity differed significantly among the treatments in both crop phases. As such, responses were pest- and season-specific rather than uniformly suppressive. These findings identify companion cropping and botanical applications as promising components of EPM within the treatments evaluated. Comparison with conventional pesticide-based or farmer-practice management is however required before recommendations for substitution or wider adoption can be made. Full article

Although the sublethal effects of botanical pesticides are critical for pest management, their role in modifying insect behaviour is frequently overlooked. In a laboratory bioassay utilising powder prepared from the leaf, stem, and root of the invasive alien plants (IAPs) Gleditsia triacanthos, Chromolaena odorata, and Schinus terebinthifolia, this study evaluated the behavioural reactions, notably repellence and locomotion, of Spodoptera frugiperda larvae. For repellence, six second instar larvae of S. frugiperda were individually placed in 30 mL vial that remained unsealed to allow larvae to exit freely if repelled and were exposed to 22% of leaf, stem and root powders of all three plant species over a 12 h period before recording the number of repelled insects. For locomotion, ten-second instar larvae were directly coated with different powder quantity 1.5 g and 2.5 g of leaf, stem, and root of all three IAPs, then released and allowed to move for 60 s on a 90 × 60 cm whiteboard. The running speed was calculated as the distance travelled per unit time. All plant-part powder exhibited significantly higher repellence than the control (0%). Gleditsia triacanthos leaf, root and stem powders showed minimal repellence, with values of 16%, 29% and 21%, respectively. However, higher rates were observed for C. odorata and S. terebinthifolia. Specifically, C. odorata stem powder achieved the highest overall repellence at 54%, whereas S. terebinthifolia performed best with its root powder at 45%. Compared to the control group, the running speed of the insects experienced a substantial reduction, decreasing by 60 to 80% when exposed to powders derived from all parts of the three IAPs. Our results suggest that the IAP powders used in this study both repel S. frugiperda and strongly limit their ability to move, highlighting their potential for behaviour-based pest control strategies. Full article

Botanical insecticides have re-emerged as promising tools within Integrated Pest Management (IPM) due to their biodegradability, chemical diversity, and potential compatibility with resistance management strategies. Although frequently considered safer alternatives to synthetic pesticides, growing evidence indicates that these compounds may also affect non-target organisms, particularly bees. This review discusses the selectivity of botanical insecticides toward pollinators by integrating historical perspectives, mechanisms of action, ecotoxicological effects, and current limitations in risk assessment approaches. Botanical insecticides may induce both lethal and sublethal effects, including alterations in behavior, locomotion, feeding, development, reproduction, and physiology across different bee groups. We also demonstrate that most available studies remain concentrated on Apis mellifera, adult workers, and acute laboratory assays, while important pollinator groups and chronic exposure scenarios remain poorly explored. Furthermore, current regulatory protocols are still largely based on models developed for synthetic pesticides. Expanding ecotoxicological approaches is therefore essential to improve pollinator safety assessments and support more sustainable pest management strategies. Full article

The sweet potato weevil, Cylas formicarius (Fabricius) (Coleoptera: Brentidae), is one of the most destructive pests of sweet potato [Ipomoea batatas (L.) Lam.] crops worldwide. Current management of the sweet potato weevil relies heavily on conventional pesticides, raising concerns about pesticide residues, environmental impacts, and the development of pesticide resistance. This study evaluated the effects of seven essential oils (EOs): eucalyptus (Eucalyptus globulus), garlic (Allium sativum), marigold (Calendula officinalis), mustard seed (Sinapis alba), peppermint (Mentha piperita), rosemary (Rosmarinus officinalis), and thyme (Thymus gobicus) against different life stages of C. formicarius under laboratory conditions. Feeding activity, oviposition, larval mortality, pupal mortality, and adult survival were evaluated using EO concentrations of 1%, 5%, and 10%, with acetone and distilled water as control treatments. Each treatment consisted of six replicates, with 10 insects per replicate. Statistical analyses were performed using logistic regression models with a binomial distribution. Significant effects of oil type and concentration were observed as lethal to weevil larval and pupal stages. Similarly, the feeding and oviposition were significantly impacted (p < 0.0001). Peppermint oil exhibited the highest efficacy, causing complete or near-complete mortality of second- and third-instar larvae and pupae at 10%. This also substantially reduced adult survival, feeding activity, and oviposition. Rosemary, thyme, and eucalyptus, at higher concentrations. Most oils almost completely suppressed oviposition. These findings demonstrate that plant-derived essential oils (EOs) exhibit significant insecticidal activity against Cylas formicarius, indicating their promise as sustainable tools for integrated pest management programs in sweet potato production systems. Full article

Lepidopteran pests cause severe global economic damage; they are currently mitigated by synthetic pesticides that trigger widespread resistance and environmental toxicity. This systematic review evaluates the potential of Piper essential oils (EOs) as high-performance, sustainable bio-based insecticides, aligning with the 12 Principles of Green Chemistry. Analyzing studies covering Piper species, we identified phenylpropanoids (e.g., dillapiole and safrole) and terpenoids as key biodegradable scaffolds for pest management. The results highlight P. aduncum and P. divaricatum for their exceptional efficacy against Spodoptera frugiperda and Plutella xylostella, often exhibiting toxicity levels comparable to botanical standards like azadirachtin. Crucially, this review reveals that Piper EOs can outperform the synthetic industrial synergist piperonyl butoxide (BPO), with natural binary mixtures enhancing insecticidal potency by up to 11-fold. Furthermore, specific EOs contribute to a preventative green strategy by causing the structural disintegration of the egg chorion. By focusing on renewable biomass and design for degradation (Principles 7 and 10), this work anchors the Piper genus as a cornerstone for the circular bioeconomy and sustainable agricultural innovation, reducing the chemical footprint of modern crop protection. Full article

The fall armyworm (Spodoptera frugiperda), a highly destructive invasive Lepidopteran pest, poses a serious threat to global agriculture, particularly maize production. Plant essential oils (EOs) represent a promising class of botanical pesticides owing to their diverse bioactivities and low environmental persistence. In this study, we evaluated the insecticidal and antifeedant activities of 40 commercially available EOs against third-instar S. frugiperda larvae. After an initial screening at 4 μL/mL, 10 EOs that caused ≥70% mortality at 72 h were selected for bioassays to estimate LC₅₀ value and chemical analysis by GC-MS. Contact toxicity assays showed that geranium EO had the highest activity (LC₅₀ = 2.105 μL/mL at 72 h), followed by cypress (2.123 μL/mL) and niaouli (2.391 μL/mL), whereas tea tree EO exhibited the lowest activity (3.592 μL/mL). Antifeedant tests revealed that clove EO caused the strongest feeding deterrence at both 24 h (antifeedant indices AFI = 72.8%) and 48 h (AFI = 63.4%), while most other EOs lost their deterrent effect within 48 h. GC-MS analysis of the 10 active EOs identified a complex mixture of monoterpenes, sesquiterpenes, and oxygenated derivatives; major constituents included D-limonene, 4-terpineol, carvacrol, caryophyllene, and longifolene. These results provide laboratory evidence that several plant EOs, particularly geranium, cypress, niaouli, and clove, possess strong insecticidal and antifeedant activities against S. frugiperda larvae, supporting their potential as eco-friendly botanical insecticides. Full article

Insects, such as the Mediterranean fruit fly (Ceratitis capitata) and the armyworm (Mythimna unipuncta), and nematodes, including the root-knot nematode (Meloidogyne incognita) and the pine wood nematode (Bursaphelenchus xylophilus), are major agricultural pests. Essential oils (EOs) from aromatic plants are promising botanical pesticides due to their bioactivity. This study evaluated the in vitro effects of EOs from Origanum vulgare, Thymus vulgaris, Ocimum gratissimum, Mentha pulegium, and Cinnamomum cassia, and their main compounds (carvacrol, thymol, eugenol, pulegone, and trans-cinnamaldehyde, respectively), on acetylcholinesterase (AChE) and α- and β-glucosidases using crude enzyme extracts. All EOs inhibited AChE, with no significant effects on glucosidases. M. pulegium EO showed the strongest inhibition in C. capitata (IC₅₀ = 0.022 mg/mL) and B. xylophilus (IC₅₀ = 0.1209 mg/mL), while C. cassia EO was most effective against M. unipuncta (IC₅₀ = 0.0020 mg/mL) and M. incognita (IC₅₀ = 0.0197 mg/mL). In silico analysis revealed selective inhibition of insect AChE by EO-derived compounds, with insignificant effects on electric eel AChE, supporting species-specific interactions. These findings highlight EOs as selective, neurotargeting, and sustainable alternatives to synthetic pesticides. Full article

Maize (Zea mays) production in Africa has been severely constrained by the fall armyworm (FAW), Spodoptera frugiperda, since the pest was first detected on the continent in 2016. Botanical pesticides are increasingly promoted as low-cost alternatives to synthetic insecticides, but the African evidence base remains scattered across plant species, formulations, experimental settings, and outcome measures. This study was conducted as a structured narrative review with an evidence-informed SWOT (strengths, weaknesses, opportunities, and threats) synthesis to evaluate the efficacy, field relevance, and practical limitations of botanical pesticides used against FAW in African maize systems. Literature published between 2016 and 2026 was identified through structured searches of Google Scholar and PubMed and was synthesized narratively because substantial heterogeneity in botanicals, extraction methods, doses, application methods, target stages, and study settings precluded meta-analysis. The review shows that Azadirachta indica currently has the strongest balance of laboratory-to-field support, while Tephrosia vogelii and Nicotiana tabacum remain promising but with conditional options because of chemotype dependence and phytotoxicity concerns. Essential oils expand the mechanistic scope of the evidence base but are still limited by volatility, weak persistence, and comparatively few field validations in African maize systems. Overall, botanical pesticides have credible potential within smallholder-oriented integrated pest management, but require standardisation, better field validation and clearer biosafety evidence, and more accessible formulations are needed before broad recommendation can be justified. Full article

The transition toward a sustainable agri-food system, aligned with agricultural and environmental policy objectives, has increased interest in aromatic plants as non-synthetic pesticide alternatives. This study focused on evaluating the antifungal potential of five specific aromatic plant species, particularly Lavandula dentata, Origanum vulgare, Thymus vulgaris, Salvia officinalis and Rosmarinus officinalis, against the phytopathogenic soil-borne fungi Fusarium oxysporum f.sp. radicis-lycopersici and Verticillium dahliae. During screening, L. dentata and T. vulgaris extracts exhibited strong in vitro fungicidal activity. Bioactive compounds previously detected in both lavender and thyme were identified in their extracts using a triple quadrupole/linear ion trap mass spectrometer. Assessment of in vitro phytoprotective action of L. dentata extract in solid and liquid growth media demonstrated inhibitory effects against F. oxysporum f.sp. radicis-lycopersici at concentrations above 1% v/v, with inhibitory effects of L. dentata extract being observed at concentrations equal to or above 2% v/v. T. vulgaris extract inhibited V. dahliae growth on solid media at concentrations at 1% v/v or above, while inhibitory effects were observed in broth media containing 2% v/v thyme extract. Seed germination tests of both L. dentata and T. vulgaris revealed a concentration-dependent reduction in their germination index (GI) at concentrations equal or above 2% v/v, apart from the effect of lavender extract on cress, where inhibition occurred at dose application above 5% v/v. In planta experiments demonstrated the complete phytoprotective action of lavender extract against F. oxysporum f.sp. radicis-lycopersici, while a marginal improvement in plant survival was observed during application of T. vulgaris extract. Full article

To better understand how botanical products affect non-target organisms, the present review focuses on the toxicity of botanical pesticides to organisms other than targeted pests, to trace a panorama on the future of sustainable agricultural models worldwide, considering the importance of ecotoxicological studies in the development of new pesticides, including botanical kinds, which are commonly recognized as essentially harmless. The review summarizes published work gathered from digital databases and highlights modern trends in pest management research and the development of novel bioinputs, including a discussion of the world’s current legislation regarding relevant agricultural innovations and field obstacles. Nanotechnology techniques are discussed as major innovations employed in the pest control field, and their employment in improving botanical pesticides is addressed and explored. In this work, we analyze the factors involved in determining the success of botanical products and their importance in the implementation of a more sustainable approach to managing crops. The results indicate a significant lack of studies focused on the effects of botanical products on non-target organisms and an increase in studies with nanoformulations. Full article

The transition toward more sustainable crop protection under the European Green Deal has accelerated the adoption of biopesticides, which are widely considered safer alternatives to synthetic pesticides. Botanical biopesticides derived from plant extracts, essential oils, and secondary metabolites are increasingly used in both conventional and organic agriculture. However, their growing use raises important questions regarding human health risks. Botanical biopesticides are complex mixtures of bioactive compounds whose composition and toxicological profiles can vary substantially depending on plant chemotype, extraction method, and manufacturing processes. This review critically examined the toxicological properties of botanical biopesticides and evaluated their regulatory assessment within the European Union (EU) framework. Particular attention is paid to scientific uncertainties, gaps in toxicological data, challenges in hazard characterization of complex mixtures, and limitations of current human exposure assessments. The review also considered how regulatory practices, user behavior, and risk perception may influence real-world exposure and potential health outcomes. By integrating experimental toxicology studies, EU risk assessment documents, and evidence on agricultural use patterns, this review assessed whether reduced intrinsic toxicity of botanical biopesticides translates into lower human health risk under current regulatory frameworks and agricultural practices. The findings underscore the need for strengthened toxicological evidence, harmonized regulatory approaches, and improved risk communication to ensure that the use of botanical biopesticides remains aligned with good agricultural practice and human health protection. Full article