Biopesticides are naturally derived inorganic materials, organic compounds, or living organisms and their byproducts that control, mitigate, or eliminate pests harmful to plants and animals. These controls can function through physical, physiological, behavioral, biochemical, or ecological mechanisms (Archana et al., 2022). Biopesticides fulfill essential criteria relevant to efficacy, environmental impact, non-target organisms, and human health. According to the U.S. Environmental Protection Agency (EPA), biopesticides are classified into three main groups: microbial biopesticides, biochemical biopesticides, and plant-incorporated protectants (Deeksha et al., 2025). However, certain pest-controlling organisms do not fit neatly into these categories, such as live plants and natural enemies that naturally suppress pests. These pesticidal plants and predatory or parasitoid insects can be categorized as macrobial biopesticides. While some literature classifies pesticidal plants as medicinal plants and beneficial insects as natural enemies, they still meet the essential criteria for biopesticides. Thus, biopesticides can be broadly grouped into four categories, as illustrated in Figure 1. It is important to note that biopesticides include natural inorganic materials and synthetic analogs. These inclusions may dilute or compromise the meaning of the “bio” prefix in the term. However, to justify this broader definition, biopesticides should be viewed from a technical perspective as nature-traceable compounds, organisms, or their parts with pesticidal effects that maintain environmentally friendly attributes, such as biodegradability, specificity, low toxicity to non-target organisms, a benign mode of action, and minimal induction of pest resistance.

Microbial biopesticides are pesticides that use microorganisms such as bacteria, fungi, algae, viruses, and protozoa as active ingredients to control pests. These microorganisms define different subcategories of biopesticides, including bacterial biopesticides, fungal biopesticides, viral biopesticides, algal biopesticides, and protozoan biopesticides. While microbial biopesticides exhibit the unique properties of biopesticides, they also possess advantages such as stealthiness and rapid replication, allowing them to overcome the frequent reapplication required by many other biopesticides. Macrobial biopesticides, on the other hand, rely on live insects and plants to control pests. This category includes natural enemies such as predators (e.g., ladybugs and praying mantises) and parasitoids (e.g., wasps), as well as pesticidal live plants that naturally repel pests, such as rosemary (Rosmarinus officinalis) and marigold (Tagetes spp.). Biochemical biopesticides are chemical compounds derived from non-living matter, microorganisms, insects, plants, and other living organisms that control pests through natural mechanisms. Examples include diatomaceous earth, chitosan, essential oils, botanical extracts, semiochemicals, insect growth regulators, plant growth regulators, and enzyme/protein inhibitors (Joshi and Chaudhuri, 2025). Plant-incorporated protectants (PIPs) are genetically engineered crops designed to resist pests or diseases. The most commonly used compounds in PIP technology include crystal toxins (Cry proteins), vegetative insecticidal proteins (Vip proteins), and RNA interference (RNAi) mechanisms. While transgenic PIPs represent an innovation in sustainable agriculture, there are growing reports of harm to non-target organisms, pest resistance, threats to biodiversity, genetic contamination, allergic reactions, and disruption of ecosystem services (Odelade et al., 2024). These concerns highlight the need for checks and balances in scientific advancements, particularly regarding the mode of action of PIPs.

Biopesticides are recognized for their diverse modes of action, which significantly reduce the risk of resistance development, a common challenge associated with chemical pesticides. Non-living biopesticide compounds exhibit multiple modes of action. For example, kaolin clay forms a physical barrier by coating plant surfaces, creating an inhospitable environment that disrupts pest movement, host recognition, feeding, and egg-laying, thereby minimizing damage (Chuskit et al., 2024). Diatomaceous earth (DE) works by creating cuticular micro-wounds on the exoskeletons of pests, leading to excessive moisture loss, dehydration, and death (Alkan et al., 2023). Similarly, chitosan (a positively charged biopolymer) employs various biochemical strategies. Its antibiosis mode of action disrupts microbial cell membranes (partly through electrostatic interactions), affecting bacteria, fungi, and viruses by increasing permeability and allowing the leakage of vital cellular components, which ultimately leads to cell death (Alkhalil, 2025). Chitosan's metal chelation mechanism sequesters calcium, magnesium, and iron, interfering with microbial growth, enzyme activity, and cellular signaling, effectively inhibiting pathogen development. The ‘Chitosan-DNA/RNA interactions' mode of action forms complexes that inhibit DNA replication, RNA transcription, and protein synthesis, culminating in cell death (Xing et al., 2015). Immunity induction through the production of defense enzymes, pathogenesis-related proteins, and secondary metabolites such as phenolic compounds and lignin enhances plant resistance against pathogens (Rosales-Castillo et al., 2025). All of these non-living biopesticide compounds provide a protective barrier for plants; however, chitosan exhibits more modes of action than others due to its complex biochemical properties and its ability to interact directly with biological membranes, molecules, and systems. This implies that organic materials are more relevant to biopesticides compared to inorganic materials.

One common mode of action shared by viral, protozoan, and bacterial biopesticides is gut disruption, a parasitic mechanism by which these agents invade their hosts and attach to insect gut receptors using toxins and other metabolites. Viral biopesticides exhibit obligate parasitism that begins when insects ingest baculoviruses, specifically nucleopolyhedroviruses (NPV) and granuloviruses (GV). Once inside the alkaline midgut, the occlusion bodies dissolve, triggering an infection that leads to viral replication, systemic spread, larval death, host liquefaction, and subsequent virus transmission within the insect population (Mehrotra et al., 2017). Protozoan biopesticides operate similarly; however, their infection begins with the ingestion of spores (cysts or oospores), and reinfection occurs via fecal contamination. The sensitivity of the insect gut to baculovirus occlusion bodies, protozoan spores, and Bt crystal proteins is likely due to active enzymes, a nutrient-rich environment, and specialized receptors (Aware and Jadhav, 2022; Rao and Jurat-Fuentes, 2020). Beyond parasitism, protozoan biopesticides have also been shown to exhibit a predatory mode of action, targeting the larvae or pupae of fungus gnats, microfauna, and nematodes, a capability facilitated by their small size, overlapping ecological niches in soil, and similar nutrient profiles (Vaselek, 2024). Fungal biopesticides act predominantly through cuticle degradation with the aid of enzymes. Once these agents penetrate the insect tissue, they produce toxins and other harmful biochemicals. For instance, Beauveria bassiana germinates on insects, breaches the cuticle, and secretes beauvericin toxin, ultimately leading to the host's death. Other modes of action exhibited by fungal biopesticides include outcompetition, as seen in Aspergillus flavus AF36, which eliminates toxigenic strains; a bioprotective barrier against disease pathogens, as demonstrated by Trichoderma asperellum against Rhizoctonia and Pythium (Kipngeno et al., 2015); mycotoxicity of weed biomass, as demonstrated by Myrothecium verrucaria; and the enhancement of plant immunity (Elkhateeb and Daba, 2019). This broader range of modes of action corresponds with a wider spectrum of target pest control, including insects, pathogens, nematodes, mites, weeds, and plant growth promotion.

Bacterial biopesticides demonstrate similar mechanisms of action as fungal biopesticides but are often richer in toxins and secondary metabolites that exhibit high bioactivity against pests and promote plant growth (Beltrán Pineda and Castellanos-Rozo, 2025). For example, Bacillus thuringiensis (Bt) produces crystal (Cry) toxins, cytolytic (Cyt) toxins, vegetative insecticidal proteins (Vip toxins), and secreted insecticidal proteins (Sip toxins), each with a distinct gut receptor binding site yet complementary (Mendoza-Almanza et al., 2020). Bt toxins, activated in the insect midgut, bind to receptors, form pores, disrupt cellular integrity, and cause fatal septicemia and subsequent insect death. Multiple toxins offer enhanced efficacy through synergistic action, broaden the pest spectrum, and significantly reduce resistance development (Aswathi et al., 2024). Binary toxins from Bacillus sphaericus, thermostable exotoxins from Burkholderia rinojensis, Mtx toxins from Brevibacillus laterosporus, Pir toxins from Photorhabdus luminescens, and toxin complex (Tc) proteins from Photorhabdus and Xenorhabdus species all exhibit significant insecticidal activity similar to the Bt mechanism of action (Mohamed et al., 2023; Nascimento et al., 2020). Ben Khedher et al. (2020), Crouzet et al. (2020), and Nalini et al. (2023) elaborated on the potential of biosurfactants produced primarily by bacteria. Notably, Bacillus subtilis synthesizes surfactin and iturin lipopeptides that effectively inhibit fungal pathogens (Markelova and Chumak, 2025). Their main mechanism of action is the disruption of cellular membranes, particularly in fungi, although these compounds also target bacteria and viruses. Additionally, some biosurfactants trigger systemic resistance in plants. Species such as Bacillus subtilis display a remarkable range of actions, including parasitism, antibiosis, competition, bioprotective barrier formation, and immune induction (Nayak, 2021). Furthermore, Bacillus subtilis excels not only in pest control but also functions as a biofertilizer, stress alleviator, and plant growth promoter (Riaz et al., 2021), showcasing its multifaceted mechanisms. This versatility positions Bacillus subtilis as an exceptionally promising biopesticide. Due to their inherent biological and ecological characteristics, bacteria present several advantages over fungi in pest management applications. These include the synthesis of potent and species-specific toxins, adaptability across diverse ecological conditions, cost-efficient scalability in production, and sustained efficacy over time.

Algal biopesticides exhibit multiple modes of action, including the formation of a bioprotective barrier, with Calothrix spp. colonizing the rhizosphere to deter Fusarium and nematodes (Babu et al., 2015); antibiosis, as demonstrated by Tolypothrix tenuis, which controls root–knot nematodes (Holajjer et al., 2013), and the stimulation of plant immunity, evidenced by Haematococcus pluvialis producing astaxanthin, which confers systemic resistance in plants against blight pathogens such as Fusarium (Eissa et al., 2025). Additionally, the biochemical bioactivity of algal biopesticides exerts a broad inhibitory effect on pest growth and feeding. For instance, Spirulina platensis limits pest feeding (Al-Qahtani, 2021), Scenedesmus obliquus causes digestive inhibition and pest repellence (Tufan-Cetin and Cetin, 2023), Chlorella vulgaris reduces insect feeding and oviposition (Cavalcanti et al., 2021), Sargassum wightii lowers insect fecundity (Petchidurai et al., 2023), Gracilaria edulis suppresses larval development (Gowthish and Kannan, 2019), and Nostoc muscorum exhibits allelopathic effects that protect plants. Algal extracts, like botanical extracts, are examples of biochemical biopesticides that control pests in diverse ways. Their modes of action include repellence and antifeedant effects (behavioral manipulation) as well as inhibition of key physiological processes such as hormonal disruption, interference with the mitochondrial electron transport chain, nerve overstimulation, disruption of calcium homeostasis, and inhibition of ATP synthesis (Casanova et al., 2023; Mevada et al., 2023; Nachammai et al., 2023). Essential oils (e.g., clove oil, thyme oil, and cedarwood oil), botanical extracts, biochemicals from insects, protein inhibitors, semiochemicals, insect growth regulators, and plant growth regulators all exert these effects to varying degrees. As indicated in Table 2, some live plants (such as marigold) utilize attractants, repellents, and allelopathy to control pests (Gupta et al., 2023), while plant-incorporated protectants (PIPs) act through gut poisoning, induction of systemic resistance, and targeted gene silencing. PIPs are genetically engineered crops with built-in defense mechanisms: Bt crops produce Bacillus thuringiensis (Bt) Cry proteins (and other toxins) that bind to insect gut receptors, causing cell rupture and starvation; virus-based crops express viral coat proteins to prevent virus replication or employ RNA interference (RNAi) to silence viral genes and essential pest genes upon ingestion, leading to developmental failure or death.

Other biological control methods include predators and parasitoids. Predators such as lady beetles, lacewings, and praying mantises actively hunt a range of pests, including aphids, thrips, and caterpillars, resulting in a significant reduction in pest populations that can damage crops. Meanwhile, parasitoids like parasitic wasps (Trichogramma spp.), tachinid flies (family Tachinidae), and braconid wasps (family Braconidae) provide targeted pest control by laying their eggs in or on specific hosts, ultimately killing them as the larvae develop (Heraty, 2017). These methods strengthen ecological balance and enhance IPM systems, making them a cornerstone of sustainable agriculture. Beyond their ecological benefits, the advantages of biopesticides are also evident in their application within proven pest management systems. Such systems promote sustainable agriculture by balancing the need for maximum turnover and yield with the preservation of natural resources that support agricultural development. Moreover, biopesticides help limit the development of pest resistance, address the shortcomings of synthetic pesticides, offer promising technological solutions to correct their limitations, and feature prominently in the stages of the IPM pyramid. The exploration of biopesticides in IPM-driven sustainable agriculture remains an active pursuit for achieving global sustainability goals.

Synthetic pesticides are persistent organic chemicals that pose serious threats to the environment, human and animal health, biodiversity, and essential ecological functions. Their presence in agricultural produce results in food contamination and economic losses due to toxicity concerns, presenting a significant challenge to agribusiness. Prolonged use fosters pest resistance and inadvertently harms beneficial, non-target organisms, further destabilizing ecosystems. Biopesticides provide a safer and environmentally friendly alternative, effectively mitigating these harmful effects while promoting agricultural sustainability, as summarized in Figure 2. By degrading rapidly, they minimize environmental pollution, lower toxicity risks to wildlife, and reduce harmful residues in soil, water, and air, promoting ecological sustainability. In contemporary agricultural systems, fast-degrading biopesticides have emerged as vital tools, delivering notable ecological and economic advantages across diverse environments. While fulfilling their primary role of pest eradication and enhancing crop yields, a renowned vineyard in California employed these biopesticides to preserve soil microbiome integrity, prevent chemical residues on grapes, and safeguard nearby water sources from runoff (Wilson and Daane, 2017). In Vietnam's Mekong Delta, rice farmers utilized them to maintain clean aquatic ecosystems, thereby protecting local fish and amphibian populations (Stadlinger et al., 2018). Awudzi et al. (2022) reported reduced residual toxicity in nutrient-sensitive soils among cocoa growers in Ghana. Similarly, Mawcha et al. (2024) documented achieving safer working environments and preserving beneficial organisms in pest management protocols in high-tech greenhouse facilities.

Their selective targeting of pests preserves pollinators and natural predators, ensuring ecological balance and supporting biodiversity. Entomopathogenic fungi-based biopesticides were employed to target aphid infestations among almond growers in Southeastern Spain, leading to a 30% rise in pollinator populations over three growing seasons and a 40% decrease in chemical pesticide use (del Valle, 2020). A similar result was observed in an apple orchard in the Pacific Northwest, where natural predators were preserved, contributing to overall orchard biodiversity (Fenibo et al., 2022). Microbial biopesticides enhance soil fertility by stimulating beneficial microorganisms and strengthening sustainable farming practices. With Bacillus subtilis-based biopesticides, smallholder vegetable farmers in Kenya were able to control Fusarium and Pythium pathogens, which resulted in increased beneficial rhizobacteria, higher yields in tomatoes and onions, and a 25% reduction in chemical use (Wafula, 2022). Novara et al. (2020) reported a pilot project in a Mediterranean organic vineyard where microbial biopesticides were introduced to stimulate beneficial soil microorganisms. Unlike synthetic pesticides, which accelerate resistance development, biopesticides utilize natural pathogens and biochemicals with diverse modes of action, making it more difficult for pests to develop resistance. In Iowa, large-scale maize producers incorporated biochemical insect growth regulators (IGRs) derived from neem and Spinosad to eradicate resistance in Western corn rootworm over 5 years (Revilla et al., 2021). Their safer profile decreases toxic exposure for farmworkers and consumers, reducing health risks (cancer risk, allergy, gastrointestinal disorders, neurological effects, etc.) associated with pesticide residues in food (Chikte et al., 2024). By preventing resistance buildup and curbing excessive pesticide application, biopesticides ensure effective long-term pest management and healthier agricultural systems. Despite their advantages, biopesticides face barriers such as short shelf life, slow action, high production costs, limited availability, regulatory constraints, and low farmer awareness, which must be addressed through targeted improvements in stability, efficiency, and adoption strategies.

Biopesticides generally exhibit shorter shelf lives than synthetic pesticides due to their biological origin, derived from living organisms (bacteria, fungi, viruses, protozoa) or natural metabolites. These components are inherently sensitive to environmental factors such as heat, light, and moisture, which hasten their degradation. Unlike synthetic pesticides, they usually lack chemical stabilizers that extend longevity, since such additives may interfere with their biological activity. Their effectiveness often depends on the viability of microbial propagules (e.g., spores or cells), which can lose activity or die over time if not stored under optimal conditions. Consequently, biopesticides typically require cool, dry, and dark environments to remain effective; any deviation reduces their performance in the field.

Shelf life varies across different categories of biopesticides. Semiochemicals, such as pheromones and plant volatiles, are the least stable due to their high volatility and susceptibility to degradation by light, air, and heat, often requiring encapsulation to extend usability (Khashaveh et al., 2025). Biochemical biopesticides, including plant extracts (e.g., neem oil), hormones, and enzymes, are moderately stable but still prone to deterioration from UV exposure, microbial contamination, or elevated temperatures, generally lasting only a few months under ideal storage conditions. Microbial biopesticides differ in stability depending on their formulation: spore-forming microbes such as Bacillus thuringiensis tend to persist longer, especially in dry formulations, while non-spore-forming microbes like many gram-negative bacteria are highly sensitive and may survive only weeks without refrigeration (Arora, 2015). By contrast, plant-incorporated protectants (PIPs), such as genetically engineered crops expressing pesticidal proteins, remain stable as long as seed viability is preserved, representing the longest effective shelf life among biopesticides. Storage requirements also vary significantly: semiochemicals need airtight, cool, and dark storage, often under refrigeration; plant extracts require sealed, opaque containers in cool and dry environments; microbial products range from room-temperature stability for spore-formers to refrigeration needs for sensitive non-spore-formers; beneficial insects require temporary holding under controlled conditions that mimic their natural habitat; while PIPs, stored as seeds, remain the most stable and practical. The short shelf life of most biopesticides has important practical implications for their distribution and adoption. Farmers and suppliers must manage strict supply chains to avoid product expiration, which can be costly and logistically challenging in rural or resource-limited areas. Improperly stored or expired products lead to reduced efficacy, inadequate pest control, and economic losses. In some cases, frequent reapplication is needed compared to synthetic alternatives, further increasing labor and operational costs (Melo et al., 2025). The limited shelf life and delayed efficacy of biopesticides underpin many of the constraints highlighted in Table 3.

One of the most cited limitations of biopesticides is their relatively slow mode of action compared to synthetic pesticides, primarily due to their reliance on biological processes. However, this limitation is not uniform across all biopesticide types; it varies significantly depending on the biological mechanism involved. Many microbial and botanical agents require time to infect, colonize, or disrupt pest physiology, which can delay visible effects for several days or even weeks. This lag reduces their suitability for emergency pest control, where rapid suppression is critical. Bacterial toxins and botanicals are at the fast-acting end of the spectrum. Bacillus thuringiensis (Bt), for instance, delivers crystalline δ-endotoxins that perforate larval midgut cells within hours of ingestion, often killing susceptible caterpillars in 2–3 days (Sellamuthu et al., 2018). This makes Bt one of the few microbial products that can be used reactively against outbreaks. Similarly, neem (Azadirachta indica), through asadirachtin, disrupts molting hormones and feeding almost immediately, as shown in cotton and rice trials where Helicoverpa armigera larval activity dropped within a few days (European Food Safety Authority (EFSA) et al., 2025). Yet even here, the “speed” is relative. Unlike synthetic pyrethroids that produce near-instant knockdown, Bt and neem still allow a window during which crop damage may occur. Fungal and viral biopesticides illustrate the biological trade-offs more sharply. Beauveria bassiana and Metarhizium anisopliae require adhesion, cuticle penetration, and systemic colonization before killing the host, a process that typically spans 5–10 days (Petlamul and Prasertsan, 2012). This delay can frustrate growers facing acute infestations, but the same infection cycle enables horizontal transmission and long-term epizootics under humid conditions. Viruses such as nucleopolyhedroviruses (NPVs) are even slower, often taking 7–14 days for larval death, yet they uniquely self-replicate, persisting in the environment for successive pest generations (Wennmann et al., 2015). Semiochemicals push this spectrum to its slowest and most indirect form. Mating disruption, mass trapping, or repellency does not kill pests at all, but instead shifts population dynamics over weeks or seasons. Codling moth pheromone dispensers in apple orchards, for example, gradually suppressed pest pressure to non-detectable levels, but only after repeated seasonal deployment (Cardé, 2021). Their value lies not in crisis response but in reshaping population ecology, reducing reliance on chemicals and extending the durability of other controls. A gradient of action speed is evident: Bt and botanicals (relatively fast, but not instant) → fungi and viruses (slow, infection-based) → semiochemicals (indirect, behavioral, long-term). Each occupies a unique ecological niche. Rather than judging “slow action” as a universal weakness, it is more constructive to see it as a continuum that aligns with different pest pressures and farming goals.

Fast-acting agents suit outbreaks; slow-acting ones build resilience and suppress pest resurgence; semiochemicals restructure pest populations at the landscape scale. Case evidence increasingly shows that blending these categories, or combining them with reduced-dose synthetics, helps bridge speed gaps (Latifian, 2025; NarandŽić et al., 2025). For example, Bt applied with Beauveria bassiana against Helicoverpa armigera provided early mortality from Bt, while fungal infections enhanced control over time (Malinga and Laing, 2024). Similarly, NPVs applied alongside sublethal insecticides improved both knockdown and persistence (Hou et al., 2024). These integrations suggest that “slow action” is not merely a limitation, but a design parameter that, when understood and managed, can expand the versatility of biopesticides within integrated pest management (IPM).

Another major constraint limiting large-scale adoption of biopesticides is their relatively high cost compared to synthetic pesticides. This cost arises from several interrelated factors spanning production, formulation, storage, and application. Production costs are typically higher because biopesticides are based on living organisms or biologically active compounds that require controlled fermentation, culturing, and downstream processing. Unlike chemical pesticides that can be mass-produced through relatively inexpensive synthesis, microbial agents demand sterile facilities, nutrient-rich media, and continuous quality control systems to maintain viability and potency. For instance, producing Beauveria bassiana or nucleopolyhedroviruses (NPVs) often involves labor-intensive processes with lower yields compared to industrial chemical synthesis (Gopalkrishna et al., 2022). Formulation and stabilization costs further drive up prices. Since microbes and natural compounds are sensitive to heat, light, and desiccation, advanced formulation technologies are needed to extend shelf life and improve field stability. These technologies add significant costs but are essential to overcome rapid degradation under field conditions. Packaging innovations. Storage and distribution costs can be substantial because many biopesticides require cold-chain logistics to preserve microbial viability. This is particularly challenging in tropical or developing regions where infrastructure is limited. At the field level, biopesticides may also appear more expensive due to the need for repeated applications and specific dosage requirements, which translates to higher labor and input costs. For example, semiochemicals such as pheromone dispensers provide excellent population-level control but require multiple units per hectare, raising the overall expense. The high cost of biopesticides varies widely across categories depending on production and formulation requirements. Microbial biopesticides such as Bacillus thuringiensis (Bt) are among the least expensive because spore-forming bacteria can be mass-produced through fermentation and remain relatively stable, making them competitive with synthetic insecticides in some regions (Kumar et al., 2019). In contrast, fungal products like Beauveria bassiana and Metarhizium anisopliae are more expensive than Bt, since they require longer culture cycles, specialized substrates, and careful drying to maintain viability (Chandwani et al., 2023). Viral biopesticides such as nucleopolyhedroviruses (NPVs) are the costliest, as they depend on labor-intensive insect rearing and complex purification. Botanical products such as neem (Azadirachta indica) fall in the mid-range but are costlier than Beauveria bassiana production (Lavoir et al., 2022). Semiochemicals, such as pheromones, tend to be relatively expensive, though generally less so than botanical pesticides (Bourguet and Guillemaud, 2016). Their cost is influenced by the precision required in chemical synthesis and the extensive use of field dispensers. For example, controlling codling moths in European orchards using semiochemicals can cost nearly twice as much per hectare compared to conventional pesticide sprays (Kovanci, 2017). Among biopesticides, Bt and Beauveria are the most cost-competitive with synthetic pesticides, whereas semiochemicals, botanicals, and viral agents remain considerably more expensive, with costs increasing in that order.

Regulatory and legal hurdles also present a major bottleneck to the wider adoption of biopesticides, often making their registration slower, costlier, and more complex compared to that of synthetic pesticides. Although biopesticides are generally safer for humans and the environment, they are subject to the same rigorous frameworks designed primarily for chemicals, which demand extensive toxicological, ecotoxicological, and environmental fate data (Soetopo and Alouw, 2023). For small-scale innovators and local producers, especially in developing countries, meeting these data requirements can be prohibitively expensive. In the United States, the EPA's Biopesticide Division has streamlined some processes, allowing faster registration for products like Bacillus thuringiensis, but even there, dossiers require detailed molecular characterization and efficacy trials. In the European Union, the regulatory landscape is particularly challenging: Directive 91/414/EEC and its successors impose strict standards, and dossiers can take 5–7 years for approval, delaying market entry and discouraging investment (Marchand, 2024). In countries such as India and Nigeria, while registration systems exist under pesticide control authorities, the lack of harmonized guidelines for microbial, botanical, and semiochemical products creates uncertainty and inconsistent approvals. Moreover, because biopesticides are living organisms or complex natural mixtures, regulators struggle to apply conventional criteria, such as defining active ingredients in botanicals or stability in viral formulations, leading to prolonged negotiations and repeated dossier revisions. Legal frameworks also differ by region, making international commercialization difficult. For instance, a product approved in the UK or USA may require a completely new dossier in South Africa (Mawcha et al., 2025a). These hurdles not only raise costs but also reduce farmer access to innovative biopesticides, ultimately slowing their contribution to sustainable pest management. Biopesticides face significant regulatory and legal hurdles that slow their commercialization. Sundh and Eilenberg (2021) maintained that in the US, the EPA provides a relatively supportive framework with reduced data requirements, allowing approvals within 1–2 years, though small firms still struggle with efficacy trial costs. In contrast, the EU applies the same strict regulations as chemical pesticides, often taking 3–8 years and demanding extensive toxicological and environmental data, which discourages SMEs. In India, registration costs are lower, but weak enforcement allows substandard products that reduce farmer confidence, while in much of Africa, unclear and fragmented regulations delay both local and international products (Reddy et al., 2024). Globally, the lack of harmonized standards means the same biopesticide must undergo costly, duplicate evaluations in different regions. These hurdles disproportionately affect smaller developers, limiting innovation and slowing the adoption of safer, sustainable alternatives.

Addressing the limitations of biopesticides requires achieving a balance between efficacy, environmental stability, and cost-effectiveness. The concept of slow release, which involves the controlled and sustained delivery of active substances over time, aligns closely with this objective. Effective slow-release systems rely on formulation technologies, protective additives, environmental stabilizers, biological enhancements, and optimized delivery methods. These strategies ensure that active ingredients are protected from degradation, consistently available to target pests at effective concentrations, and reduce the need for frequent reapplication. Accordingly, the discussion will now explore how each of these technologies facilitates slow release and serves its intended functions.

The effectiveness of biopesticides depends, in part, on their potency, formulation, and method of application. There are several application methods, which will be discussed here, starting with seed treatment. Seed treatment application of biopesticides involves coating seeds with biological agents, such as beneficial bacteria, fungi, or viruses, before planting. These biopesticides create a protective barrier, preventing soil-borne pathogens and insect pests from attacking young seedlings during germination and early growth stages. There are different types of seed treatments, including seed bio-priming, seed encapsulation, and gel seeding. Bio-priming integrates biological seed treatment with hydration, coating seeds with beneficial microorganisms like Trichoderma spp., Bacillus subtilis, or Pseudomonas fluorescens to suppress soil-borne pathogens and promote plant growth (Shil et al., 2025). This method improves seed vigor, accelerates germination, and strengthens plant defense mechanisms while reducing reliance on chemical pesticides. Seed encapsulation, on the other hand, encloses seeds within a protective coating, often using biodegradable polymers, hydrogels, or nutrient-rich materials, to enhance viability, storage, and controlled germination (Sarma et al., 2023). Widely used in precision agriculture, encapsulation ensures uniform seed distribution and facilitates microbial delivery for improved crop establishment. Gel seeding involves suspending seeds in a moisture-retaining gel to improve germination and early seedling development, providing a controlled environment that maintains hydration and prevents desiccation (Western, 2012). Particularly beneficial for small or delicate seeds like carrots and lettuce, gel seeding enhances seed-to-soil contact, reduces transplant shock, and improves seedling survival rates, making it a valuable tool for optimizing crop performance. Despite its simplicity, this application method has demonstrated consistent efficacy across diverse agricultural systems, as evidenced by a global meta-analysis by Lamichhane et al. (2022). The analysis reported significant improvements, including a 7% increase in seed germination, a 91% improvement in seedling emergence, a 53% enhancement in plant biomass, a 55% reduction in disease incidence, and a 21% increase in crop yield. Representative success stories of seed treatment are summarized in Table 5.

Some benefits of seed treatments include a reduced need for foliar pesticide applications and a lower quantity of active ingredients compared to traditional spraying methods. Choudhary et al. (2021) has shown that biopesticide seed treatments can effectively control soil-dwelling insects, plant-parasitic nematodes, fungal pathogens, root rot, and damping-off diseases. Seedling root dip is a valuable technique that enhances plant establishment, early growth, and resistance to soil-borne diseases by treating seedling roots with a nutrient-rich or biologically active solution before transplanting. The process involves trimming damaged or excessively long roots and then immersing them in the prepared dip solution for several hours, ideally up to 24 h, to allow absorption of essential nutrients and beneficial microbes (Gregorio et al., 2010). This coating helps seedlings adapt to new soil conditions, reducing transplant shock and improving survival rates, making root dips particularly useful for bare-root plants. The root dip mixture typically includes organic materials such as compost, manure, or microbial inoculants like Trichoderma spp. and Pseudomonas fluorescens, which promote beneficial soil interactions while suppressing harmful pathogens. By optimizing root health and microbial activity, this method ensures stronger plant development and resilience in various growing conditions. Seedling root dip treatment is especially effective for crops that require early protection against nutrient deficiencies and environmental stress (Ronga et al., 2021). Research highlights its benefits for different plant types, particularly those vulnerable to soil-related challenges. For instance, Ronga et al. (2021) demonstrated that pepper seedlings treated with phosphorus-enriched root dips exhibit improved nutrient uptake and resistance to adverse soil conditions. Similarly, rice seedlings benefit from phosphorus and biofertilizer slurry treatments, leading to stronger root development and increased resilience against acidic soils (Goswami and Kalidas-Singh, 2023). By integrating seedling root dips into cultivation practices, farmers can enhance plant vigor, improve crop survival rates, and establish more sustainable agricultural systems.

Soil drenching is an effective technique for applying biopesticides directly to the root zone through water-based solutions, ensuring beneficial microbes or bioactive compounds penetrate the soil to target pests, pathogens, and nematodes while promoting plant health (Sri et al., 2025). Unlike foliar sprays, this method allows biopesticides to establish themselves in the rhizosphere, forming a protective barrier against harmful organisms. Common biopesticides used in soil drenching include microbial agents such as Trichoderma spp., Bacillus subtilis, and Pseudomonas fluorescens, which suppress fungal infections and enhance root development. Additionally, entomopathogenic fungi like Beauveria bassiana and Metarhizium anisopliae effectively control soil-dwelling insect pests. The success of soil drenching depends on maintaining optimal conditions, including soil moisture, pH balance, and proper dilution ratios, to ensure microbial activity and pest suppression. For best results, soil moisture should be at field capacity, meaning adequately moist but not waterlogged, allowing biopesticides to reach the root zone without excessive runoff. The ideal pH range is 5.5–7.0, as extreme acidity or alkalinity can diminish microbial viability (Adeniji et al., 2024). Dilution ratios vary depending on the formulation, but a common recommendation is 1:100 to 1:500, ensuring proper dispersion while maintaining potency for effective pest control (Aremu et al., 2012). Soil drenching helps manage root-knot nematodes (Meloidogyne spp.), fungal pathogens such as Phytophthora spp., Fusarium spp., and Pythium spp., as well as aphids and scale insects (Aphis spp., Coccidae family), using moist, organic-rich soils that are ideal for the activity and persistence of these BCAs. Soil drenching has shown notable success across crops: Trichoderma harzianum reduced damping-off in tomato and improved seedling vigor in India (Bhardwaj, 2019); Pseudomonas fluorescens suppressed sheath blight and enhanced yield in rice (Nur Mawaddah et al., 2023); and Beauveria bassiana controlled root-feeding insects while promoting growth in cucumber under greenhouse conditions (Spescha et al., 2023). These examples demonstrate that soil drenching can combine disease suppression, pest reduction, and plant growth promotion, making it a versatile strategy in sustainable agriculture.

Agricultural pest control mechanisms brought about through irrigation systems are known as microbigation. This technique focuses on pest control and soil health improvement by introducing beneficial microbes and entomopathogenic nematodes that suppress harmful pathogens, enhance plant resilience, and promote sustainable farming practices. This method integrates pest management with plant nutrition delivery, ensuring that biopesticides reach the root zone and foliage effectively. Thus, microbigation is particularly useful for managing soil-borne diseases and improving microbial diversity in agricultural ecosystems (Bonaterra et al., 2022). A mix of microbigation and fertigation reduces labor costs, minimizes environmental contamination, and enhances the absorption of biopesticides, and maintains soil moisture levels, promoting microbial activity and thus leading to improved pest control and crop health. The controlled delivery through irrigation systems ensures that biopesticides remain active for longer periods, reducing the need for frequent applications. The active period of biopesticides can further be enhanced through liquid formulations (emulsion and suspension), encapsulation formulations (microencapsulation), and oil-based formulations. The liquid formulation ensures uniform distribution, microencapsulation enhances stability, and the oil-based formulation promotes adherence to the root system (Hegde and Vijaykumar, 2022). To avoid clogging in irrigation lines and enhance absorption by plant roots, microbial biopesticides should be formulated with stabilizers and surfactants. For optimal operation, the water pH should be around 5.5–7.0 to avoid clogging, the temperature should be around 18–25 °C to support microbial activity, and using mesh filters (100–200 microns) helps remove debris and prevent blockages (Wolcott et al., 2022). Bacillus thuringiensis and Trichoderma spp. are better suited for this application method because they target soil-borne pathogens and insect pests. Microbigation has shown notable successes: in Italy, Trichoderma harzianum and Paecilomyces lilacinus remained viable and suppressed soil-borne pathogens (Boari et al., 2008); in Brazil, drip-applied Azospirillum brasilense in maize enhanced root growth, nitrogen uptake, and yield (Galindo et al., 2022); and in Spain, Trichoderma asperellum fertigation in tomato reduced Fusarium oxysporum while improving vigor and fruit production (Leuratti et al., 2025), confirming the potential of irrigation-based microbial delivery for the sustainable intensification of agriculture.

Trunk injection is a precise biopesticide application method that delivers pest control agents directly into the stem or trunk of woody plants. By injecting biopesticides into the xylem, active ingredients are transported throughout the plant via the transpiration stream, ensuring systemic protection against pests such as borers and fungal pathogens (Li and Nangong, 2022). This technique is especially valuable for managing diseases in trees and high-value crops where foliar sprays or soil drenches may be ineffective or environmentally hazardous. One of its key advantages is the efficient delivery of biopesticides while minimizing environmental impact. Unlike aerial or soil applications, trunk injection eliminates spray drift, reduces worker exposure, and prevents contamination of non-target organisms. It is widely used in forestry, urban landscaping, and commercial agriculture, particularly for crops like avocados and citrus trees (Archer, 2022; Li and Nangong, 2022). Biopesticides used in trunk injection typically consist of microbial agents, botanical extracts, and carrier substances that facilitate systemic movement within the plant. Microbial biopesticides, such as Beauveria bassiana and Metarhizium anisopliae, target insect pests by colonizing their bodies and disrupting physiological functions. Botanical extracts, including essential oils like mint and cinnamon, have been studied for their ability to move through the vascular system, providing pest control benefits (Werrie et al., 2021). Carrier substances, such as water-based or oil-based solutions, improve absorption and stability, ensuring effective distribution of active ingredients. This method is used to treat various plant diseases, particularly those affecting trees and woody plants. Common diseases managed through trunk injection include oak wilt, Dutch elm disease, and sudden oak death (Phytophthora infection). According to Passey et al. (2019) trunk injection can aid combat apple scab and fire blight in apple trees, root rot and thrips in avocado trees, and powdery mildew and downy mildew in grapevines. In Florida, injection of oxytetracycline and microbial antagonists into citrus trees significantly suppressed Candidatus Liberibacter asiaticus (Hu et al., 2018), the causal agent of huanglongbing, prolonging tree productivity. In California vineyards, trunk injection of Trichoderma harzianum reduced grapevine trunk diseases caused by Phaeomoniella chlamydospora and Neofusicoccum spp., improving vine vigor and yield (Wallis et al., 2025). Similarly, in Central America, avocado orchards injected with Bacillus subtilis formulations experienced reduced wilt symptoms associated with Ralstonia solanacearum and Phytophthora cinnamomi, contributing to healthier root systems and an extended orchard lifespan (Hyakumachi et al., 2013). These examples demonstrate trunk injection's potential as a precise delivery method that enhances disease suppression while minimizing off-target effects.

Aerial application involves the dispersal of agricultural treatments using aircraft or drones, enabling extensive coverage of large farms while optimizing labor efficiency and ensuring uniform distribution of the applied substances. This method is designed for speed, precision, and effectiveness, helping to control pests, enhance crop productivity, and reduce soil compaction. Technological advancements, such as GPS-guided spraying and precision targeting, have further improved aerial application, making it more effective and environmentally sustainable (Rathod and Shinde, 2023). Its effectiveness depends on low wind speeds (below 10 mph) to minimize drift, moderate temperatures to prevent rapid evaporation, and humidity levels above 50% to ensure proper adhesion of spray droplets to crops (Awais et al., 2022). The best time for aerial spraying under these conditions is early morning or late afternoon when weather factors are most favorable. The efficiency of this method is further enhanced by factors such as large land area, uniform crop height, and even terrain, ensuring optimal coverage and penetration (Chen H. et al., 2021). To address environmental challenges that may impact the effectiveness of the application, GPS-guided spraying and precision targeting may be required to minimize waste and maximize efficiency. Environmental sustainability is maximized when the applied substances are biopesticides or other biological control agents, reducing chemical exposure and promoting eco-friendly pest management. As technological advancements continue, drones may be equipped with sophisticated sensors and data analytics capabilities to enable real-time monitoring of pest populations, leading to more strategic and environmentally friendly spraying techniques, defining precision agriculture. In Brazil, aerial spraying of Bacillus thuringiensis (Bt) formulations on soybean successfully controlled caterpillars such as Anticarsia gemmatalis, reducing chemical insecticide use across millions of hectares (Cai and Dimopoulos, 2024). In North America, aerial release of baculoviruses against the gypsy moth (Lymantria dispar) achieved significant population suppression while preserving natural enemies. Likewise, in Australia, aerial application of entomopathogenic fungi such as Metarhizium anisopliae has been employed to manage locust swarms, providing environmentally safer alternatives to broad-spectrum chemical insecticides (Scanlan et al., 2001). These case studies highlight the potential of aerial biopesticide applications to deliver scalable and effective solutions within integrated pest management programmes.

The most suitable biopesticides for aerial application in agriculture are microbial biopesticides due to their effectiveness, environmental safety, and scalability. Among these, Bacillus thuringiensis (Bt) is widely used for controlling caterpillar pests in crops like corn and cotton because of its stability as a spore-forming bacterium and its tolerance to UV exposure (Khan et al., 2016). Similarly, entomopathogenic fungi such as Beauveria bassiana and Metarhizium anisopliae have proven highly effective in oil-in-water formulations that withstand aerial dispersal conditions, targeting a broad spectrum of insect pests (De Oliveira et al., 2018). Viral biopesticides like Helicoverpa armigera nucleopolyhedrovirus (HaNPV) are used in cotton pest management and benefit from microencapsulation techniques that enhance their persistence in open environments (Pobożniak and Olczyk, 2025). These microbial biopesticides, their formulations, and the optimal environmental conditions are also suitable for foliar spray, a less sophisticated method of biopesticide application. It involves applying biologically derived substances directly to plant leaves (using sprayers like handheld, boom, backpack etc.), allowing for rapid absorption and enabling plants to utilize the active compounds quickly to combat pests and diseases. Foliar spray aids the active ingredient target insect pests, fungal infections, and bacterial pathogens that reside on the plant surface, reducing their population before they can cause significant damage. One unique advantage of foliar application is its ability to deliver biopesticides precisely to areas where pests are most prevalent. Modern advancements such as drone-assisted spraying and electrostatic technology improve droplet adhesion and coverage, maximizing pest control efficiency (Wu et al., 2024). Foliar spray remains one of the most widely adopted methods of biopesticide application, with demonstrated success across diverse crops. In India, foliar spraying of Beauveria bassiana effectively reduced whitefly (Bemisia tabaci) infestations in cotton, contributing to lower reliance on synthetic insecticides (Ghosal, 2018). In Kenya, neem-based foliar formulations controlled diamondback moth (Plutella xylostella) in cabbage, improving marketable yield and farmer income (Akol et al., 2002). Similarly, in the United States, foliar applications of Bacillus subtilis biocontrol products suppressed powdery mildew in strawberries, enhancing fruit quality and reducing disease-related losses (Awan and Shoaib, 2019). These instances highlight foliar spraying as a reliable and effective approach for administering biopesticides within integrated crop protection frameworks. Table 6 presents a consolidated overview of the seven application methods, outlining their respective strengths, weaknesses, opportunities, and threats, along with supporting diagrams and cited references.

Once the active ingredients are delivered to specific parts of plants, they produce three primary effects: antimicrobial activity, growth promotion, and/or induction of systemic resistance (ISR). Microbial biopesticides employ various mechanisms to directly inhibit pathogen growth and insect herbivores. These beneficial microbes secrete a diverse array of secondary metabolites, including toxins, chitinases, glucanases, lipopeptides, siderophores (iron-chelating molecules), hydrogen cyanide, and phenazine derivatives, all exhibiting broad-spectrum antimicrobial activity. Some of these microorganisms (mostly bacteria) also act as plant growth-promoting microorganisms (PGPMs), enhancing crop growth through intricate biochemical processes that improve nutrient acquisition and bolster plant defenses (Liu et al., 2025). For example, PGPMs synthesize phytohormones such as auxins, gibberellins, and cytokinins, which stimulate cell division, elongation, and differentiation, thus enhancing overall plant development. Moreover, certain PGPMs, like rhizobia and free-living nitrogen fixers, produce nitrogenase, converting atmospheric nitrogen into nitrate essential for plant proteins and other cellular components. Many PGPMs additionally release organic acids that solubilize otherwise inaccessible phosphorus in the soil, making this critical nutrient available for uptake. These processes support vital metabolic functions ranging from chlorophyll synthesis to DNA replication, contributing to both immediate growth and long-term plant health. Furthermore, when biological control agents (BCAs) interact with plant cells, their components are recognized as microbe-associated molecular patterns by pattern recognition receptors (Bhardwaj et al., 2024). This recognition triggers signaling cascades, such as mitogen-activated protein kinase pathways, which lead to the upregulation of defense-related genes and the production of protective compounds, including phytoalexins and pathogenesis-related proteins. The stability of the biopesticides in these processes is enhanced by appropriate formulation and delivery techniques, as extensively elaborated in Kala et al. (2020). Given the wide array of biopesticides and their complementary advantages over synthetic chemical pesticides it will be of interest to understand their adoption and use in sustainable agriculture.

The application and implementation of biopesticides in large-scale farming is gaining traction in defining sustainable agriculture. Almost all types of biopesticides types are used, but microbial biopesticides are the most popular. Microbial biopesticides have emerged as powerful tools in sustainable pest management, offering effective alternatives to synthetic pesticides amid growing concerns over resistance development and environmental impact. Raghuvanshi (2015) documented the effective field deployment of entomopathogenic fungal consortia comprising Beauveria bassiana and Metarhizium anisopliae, similar to commercial formulations such as Bio-Magic Plus^®, Eco-Bio Insecticide^®, and Myco-Jet^®, in Maharashtra, India. When administered to crops including aubergine, sugarcane, tomato, and chili, these biocontrol agents achieved pest suppression efficiencies of up to 85%, with concomitant yield enhancements reaching approximately 25%. Mollah and Hassan (2023) reported that the sequential deployment of Trichoderma harzianum, comparable to commercial formulations such as TRICHODEX^®, Foster^®, and Bactogang-24^®, in aubergine (Solanum melongena) cultivation in Bangladesh markedly suppressed Leucinodes orbonalis infestations. This intervention resulted in a yield increase from 14.8 to 21.7 tons per hectare, representing a 46% enhancement relative to untreated control plots. Bacillus thuringiensis (Bt), as demonstrated by Ortiz and Sansinenea (2022), was formulated in products analogous to Dipel^®, Thuricide^®, and Ecotech Pro^® and applied to maize and various horticultural crops in Mexico and Colombia. These biopesticidal applications achieved pest suppression rates between 70% and 90%, accompanied by yield increases of 15% to 20%, thereby validating the compatibility of Bt-based interventions within both organic and conventional agricultural paradigms. Similarly, Fenibo et al. (2023) documented a report in which smallholders employing Bt in maize and cabbage farming in Ghana and Kenya experienced pest reductions of 65%−85%, yield increases of up to 28%, and a 60% decrease in synthetic pesticide use. A study conducted in commercial vegetable greenhouses in the Netherlands assessed the efficacy of Pseudomonas fluorescens, comparable to Bio-Foray^® and Pseudostar^®, and Trichoderma harzianum in suppressing soil-borne phytopathogens (Mihajlović et al., 2017). The treatments reduced disease incidence by 60%, improved plant resilience, and led to 10%−15% higher yields compared to chemically managed controls. The observed trend (as shown in Table 7) of using microbial biopesticides suggests that the percentage of pest reduction is higher than the percentage of reduction in synthetic pesticide use, which, in turn, is higher than the percentage of yield increase.

The trend observed in microbial biopesticides also appears in the use of botanical biopesticides in sustainable agriculture. For example, neem-based extracts from Azadirachta indica, widely applied in Indian cropping systems, achieved up to a 75% reduction in pest populations, a 50% decrease in synthetic pesticide use, and a 20% increase in crop yields (Ngegba et al., 2022). Some examples of commercial neem extract products are NeemBaan^®, Margosom^®, Anosom^®, and Derisom^®, while Pyrethrum 5EC^®, EverGreen^®, and Monterey Bug Buster-O^® are examples of pyrethrum-based formulations. Similarly, pyrethrum-based formulations derived from Chrysanthemum species, utilized in African fruit orchards, resulted in an 85% pest reduction, a 60% decline in chemical pesticide application, and a 25% yield boost (Riyaz et al., 2022). The case studies reported by Munyore and Rioba (2020), Lengai et al. (2020), and Malinga and Laing (2022) follow the same trend. Munyore and Rioba (2020) reported a 65% decline in pest incidence, a 45% reduction in supplementary pesticide usage, and an 18% improvement in marketable yields where garlic (Allium sativum) extracts were used in greenhouse vegetable production. Lengai et al. (2020) recorded a 70% decrease in pest pressure, a 55% reduction in conventional pesticide reliance, and a 20% increase in yield where chili pepper (Capsicum spp.) extracts were used in integrated pest management strategies for tomatoes and cucumbers across Southeast Asia and Africa. As expected, Malinga and Laing (2022) achieved a 75% reduction in bollworm infestation, a 65% decrease in synthetic pesticide use, and a 22% improvement in yield while treating a cotton plantation with eucalyptus oil extracted from Eucalyptus species. The trend can be expressed as ↓I% > ↓P% > ↑Y%, where ↓I% is the percentage reduction of pest infestation, ↓P% represents the percentage reduction of synthetic pesticide use, while ↑Y% stands for the percentage increase in yield. For simplicity, we term this expression the IPY trend, representing the common direction of tiered performance indicators for the successful application of biopesticides.

The most significant parameter that drives the trend is the pest loss percentage (↓I%), which can be used to indicate the success of biocontrol measures, as shown by the use of entomopathogenic nematodes (EPNs) in different major cropping systems. In Poland, Steinernema feltiae (e.g., Entonem^® and NemaShield^®) and S. carpocapsae (e.g., Entonem^®) were successfully applied as foliar treatments in wheat fields to combat the cereal leaf beetle (Oulema melanopus), achieving up to 70% larval suppression and improving plant vigor (Mazurkiewicz et al., 2021). In Egypt, large-scale integration of Heterorhabditis bacteriophora (NemaSeek^®) and S. glaseri (comparable to Galleria-Pro^®) with organic soil amendments in wheat and barley fields led to 60%−85% suppression of cereal cyst nematodes and yield gains under sustainable cultivation practices (Abd-Elgawad, 2025). A European case study in organic horticulture demonstrated that EPNs like H. bacteriophora and S. feltiae, applied via drip irrigation in vegetable systems, achieved up to 90% pest control, confirming their compatibility with large-scale organic systems (Furmanczyk and Malusà, 2023). Additionally, in North African tomato production, cadaver-based applications of Heterorhabditis indica provided 65–75% reduction in root–knot nematodes and sustained crop protection for up to 2 months while improving fruit yield and quality (Abd-Elgawad, 2024). Koppenhöfer et al. (2020) reported that globally, mechanized application of S. feltiae and H. bacteriophora in strawberries and turfgrass systems yielded 50%−90% pest reduction, confirming the adaptability of EPNs to high-value crops and scalable operations. These studies affirm the scalability, pest specificity, and value of EPNs in ecologically intensive farming models.

Recent large-scale field studies have underscored the robust potential of natural enemies to deliver significant pest suppression and crop protection benefits in commercial agriculture. In Belgian cereal farms, the implementation of within-field wildflower strips led to a 60%−85% increase in aphid predation by natural enemies such as lady beetles and hoverflies, demonstrating the ecological intensification value of conservation biological control (Hatt et al., 2017). Beyond pest management, the integration of within-field wildflower strips confers a range of ancillary agronomic benefits. These include enhanced biodiversity, improved soil structure, attenuated soil erosion, optimized water infiltration, bolstered pollination efficacy, and elevated aesthetic quality of agricultural landscapes. Similarly, a meta-analysis across Sub-Saharan African vegetable systems revealed that augmentative releases of predators like Phytoseiulus spp. achieved 35%−80% pest suppression while preserving the diversity of native beneficial insects (Ratto et al., 2022). In Chinese wheat systems, large-scale applications of Aphidius gifuensis and Chrysoperla sinica led to up to 80% reduction in aphid populations and 15%−18% yield increases, reinforcing the yield benefits of natural enemy-based interventions (Ali et al., 2018). Mass releases of Trichogramma spp. in Southeast European maize fields effectively suppressed Ostrinia nubilalis by over 70%, drastically reducing pesticide reliance and representing one of the most successful parasitoid-based controls in monoculture grain systems (Ivezić et al., 2022). Furthermore, in organic strawberry systems in California, the strategic use of banker plants in combination with Orius insidiosus reduced thrips and whitefly damage by 60%, contributing to improved fruit quality without synthetic inputs (Van Lenteren, 2012). Collectively, these studies affirm that natural enemies provide ecologically grounded alternatives to chemical pest control that can be effectively applied across diverse crops and regions.

Advances in agroecological pest control have demonstrated the effectiveness of live pesticidal plants, used as repellent, banker, and trap crops (RBT plants), in large-scale farming systems, particularly within push-pull frameworks. Push–pull frameworks constitute an integrated pest management (IPM) system that employs dual tactical interventions: intercropped repellent species that deter pest colonization within the field (push), alongside perimeter-planted attractant trap crops that lure pests away from the target crop (pull), thereby optimizing pest suppression and safeguarding crop yield. In East African cereal systems, the integration of Desmodium (push) and Brachiaria (pull) across over 500,000 hectares has consistently achieved over 80% suppression of stemborers and 90% control of Striga weed, leading to substantial maize yield recovery (Khan et al., 2023). Similarly, a novel combination of nighttime light traps with push–pull intercropping in Ethiopia reduced fall armyworm (Spodoptera frugiperda) egg mass infestations by up to 90%, enhancing farmer-led maize protection efforts (Gebreziher and Gebreazgaabher, 2024). The later authors also reported that in China, maize used as a trap crop in vegetable systems attracted up to 80% of fall armyworm (Spodoptera frugiperda) infestations to field margins, significantly limiting pest pressure on main crops and reducing pesticide use.

Cabbage farms in Tanzania that deployed an integrated pest management approach, utilizing African nightshade as a repellent and mustard as a trap crop, achieved up to an 80% suppression of diamondback moth populations, resulting in yield increases of 20%−30% without the use of synthetic pesticides (Okoma et al., 2025). In crucifer vegetable production, push–pull systems integrating marigold and mustard achieved a 70%−85% reduction in pest populations and enhanced beneficial parasitoid activity, as demonstrated in Brazil (da Silva et al., 2022). Likewise, Kenyan tomato systems that utilized Ocimum spp. as repellent intercrops and decoy trap plants saw up to 78% control of Tuta absoluta, alongside increased biodiversity of natural enemies (Chidawanyika et al., 2025). Finally, UK strawberry farms using synthetic semiochemical-enhanced trap crops around fields reported 60%−70% suppression of the European tarnished plant bug (Lygus rugulipennis), a significant outcome achieved without synthetic pesticides (Fountain et al., 2021). These case studies jointly substantiate the strategic transferability of botanical intercropping and trap-cropping systems as sustainable pest management interventions across diverse agroecosystems. Beyond using non-crop live plants, crop plants also have been fortified with protectants, producing RNAi- and Bt-crops.

RNA interference (RNAi) is a post-transcriptional gene silencing mechanism that utilizes double-stranded RNA (dsRNA) to initiate a cascade resulting in the degradation of complementary messenger RNA (mRNA) sequences. The dsRNA is initially processed into short interfering RNAs (siRNAs) by the RNase III enzyme Dicer (Zhang et al., 2025). These siRNAs are then incorporated into the RNA-induced silencing complex (RISC), where the strand complementary to the target mRNA is selectively retained. The RISC, with Argonaute proteins as central components, directs sequence-specific cleavage of the target mRNA, thereby effectively downregulating gene expression. RNAi presents a highly promising strategy for pest control through its inherent target specificity (Chen et al., 2024). This molecular approach allows for the silencing of genes crucial for pest reproduction, survival, or pathogenicity, without adversely affecting non-target or beneficial organisms. The specificity arises from the requirement for near-perfect sequence complementarity between the siRNAs and the pest's mRNA, ensuring that off-target gene suppression is minimized. Deployment strategies for RNAi in agroecosystems include both transgenic and exogenous methods. In host-induced gene silencing (HIGS), crops are genetically engineered to express dsRNA constructs that target pest genes, thereby conferring systemic resistance through intracellular uptake and processing. Alternatively, spray-induced gene silencing (SIGS) involves the topical application of formulated dsRNA, often enhanced by nanoparticle carriers or other stabilizing agents to improve environmental persistence and uptake efficiency. Current research focuses on optimizing dsRNA delivery, enhancing stability under field-like conditions, and broadening the spectrum of target pests through refined bioinformatic analyses to avoid off-target effects (Basso et al., 2025). As advances in molecular biology and nanotechnology continue to evolve, RNAi is poised to become a cornerstone of species-specific, environmentally conscious pest management strategies in modern agroecosystems.

Recent field-scale studies have shown RNA interference (RNAi) to be a highly promising strategy for pest control in large-scale agriculture, with several applications achieving remarkable suppression rates. In the United States, MON 87411 transgenic maize expressing dsRNA targeting the Snf7 gene in Diabrotica virgifera (Western Corn Rootworm) recorded over 95% suppression of pests, significantly reducing yield losses and setting a benchmark for RNAi-based pest control (Mendoza-Alatorre et al., 2025). A follow-up regulatory trial also confirmed >90% WCR reduction with minimal off-target impacts, bolstering its environmental safety (Christiaens et al., 2022). In Germany, gene target screening via dsRNA in Leptinotarsa decemlineata (Colorado potato beetle) achieved >80% pest mortality by silencing critical genes involved in development and metabolism (Mehlhorn et al., 2021).

Similarly, in Brazil, the topical application of non-transformative dsRNA targeting Spodoptera frugiperda ATPase genes led to up to 80% larval mortality under field conditions, highlighting the feasibility of spray-based RNAi (Cagliari et al., 2019). In India, dsRNA foliar sprays on chickpea crops targeting Helicoverpa armigera protease genes resulted in over 75% larval suppression and increased pod yields in open-field evaluations (Mamta and Rajam, 2017). Field-scale RNAi trials in Belgium tested formulations for the Colorado potato beetle and Tuta absoluta, achieving 65%−85% pest reduction while emphasizing product scalability and readiness for regulatory clearance (De Schutter et al., 2022). Lastly, field trials in southern China applied siRNA sprays against Plutella xylostella on crucifer crops, achieving up to 70% larval mortality, thereby reducing reliance on conventional insecticides (Gong et al., 2013). These case studies demonstrate that RNAi can provide species-specific, effective, and scalable pest control solutions across diverse agroecosystems, as is also expected from Bt-crops.

The large-scale deployment of Bt maize (Zea mays) expressing the Cry1Ab protein in the United States since the mid-1990s has proven highly effective in controlling populations of the European corn borer (Ostrinia nubilalis). This genetic modification has contributed to increased yield stability through consistent pest suppression, significantly reducing the dependency on chemical insecticides. The implementation of integrated refuge strategies (planting non-Bt crops alongside Bt crops) further supports the durability of Bt maize by mitigating the risk of field-level resistance development, thereby ensuring the sustainability of pest management practices (Ostlie et al., 1997). Low refuge compliance in Bt maize has been reported to accelerate pest resistance development (Kang et al., 2025). In China, extensive cultivation of Bt cotton (Gossypium hirsutum) has led to a marked decline in populations of the major pest cotton bollworm (Helicoverpa armigera). The targeted expression of Bt toxins improves pest suppression while simultaneously enhancing crop productivity, decreasing pesticide application rates, and contributing to improved environmental conditions and farmworker safety (Lü et al., 2018). In South Africa, empirical studies validate the field performance of Bt maize, particularly in mitigating infestations from key pests such as Busseola fusca. The expression of specific Cry proteins significantly reduces pest pressure, leading to improved crop yields and a notable decrease in pesticide reliance (Kotey et al., 2017). Just recently, Nigeria approved four TELA maize varieties in January 2024. These are stacked for insect resistance and drought tolerance, with reported yield potentials reaching up to 10 t/ha under optimal management, significantly higher than the national average of approximately 6 t/ha for comparable hybrids (Oyekunle et al., 2023). However, not all experiences have been positive. Burkina Faso, once an early adopter of Bt cotton, phased out its use in 2016 due to concerns over lint quality (Luna and Dowd-Uribe, 2020). This case serves as a cautionary example, highlighting the importance of pairing biotech traits with high-performing cultivars and robust seed systems. In North America, genetically modified Bt maize (Zea mays) and Bt cotton (Gossypium hirsutum) predominate, owing to their enhanced resistance to lepidopteran pests and the resultant reduction in synthetic insecticide applications (Yang et al., 2022). In Asia, nations such as India and China have widely adopted Bt cotton, while the Philippines has recently sanctioned the commercialization of Bt brinjal (Herring, 2023). While Bt crop biotechnology is predominantly utilized in corn and cotton, it has also expanded into other economically significant crops.

The global adoption of Bt crops has similarly influenced agricultural sectors beyond maize and cotton. In India, Bt brinjal (Solanum melongena) has shown efficacy in controlling the fruit and shoot borer, although concerns remain regarding genetic diversity and potential biopiracy implications. China's Bt rice (Oryza sativa) demonstrates strong potential for yield enhancement and pesticide reduction, but its commercialization has faced regulatory delays linked to economic and policy concerns, with an opportunity cost of $12 billion per year (Jin et al., 2019). Since 1995, Bt potatoes (Solanum tuberosum) have been used in the United States to manage Colorado potato beetle (Leptinotarsa decemlineata) infestations, reducing dependence on certain chemical insecticides. Their integration into integrated pest management (IPM) strategies has improved environmental sustainability and agricultural productivity, benefiting growers, consumers, and the U.S. economy (Anon, 2000). Further research in the Philippines highlights that adoption patterns of Bt tomato (Solanum lycopersicum) and Bt eggplant, particularly in small-scale farming systems, have demonstrated reductions in insecticide use while increasing marketable fruit yields (Ruane et al., 2023). Brazil's Bt soybean (Glycine max), widely cultivated for over a decade, has played a critical role in insect pest suppression, with adoption rates exceeding 80% by 2020/2021 and reaching 94% in the 2023/2024 crop season (Bueno et al., 2025). Meanwhile, Ghana has transitioned from confined trials to full regulatory approval, culminating in the commercial release of a pod-borer-resistant (PBR/Bt) cowpea (event 709A) between 2022 and 2024 (Addae et al., 2020). This variety targets yield losses caused by Maruca and other pod borers. The Philippines became the first Asian country to approve Golden Rice for commercial propagation in July 2021. This biofortified rice aims to combat vitamin A deficiency, particularly among children, though its approval has faced legal and civil society challenges. These case studies underscore the varied benefits, challenges, and regulatory frameworks shaping Bt crop technologies across different regions, emphasizing their significance in sustainable agriculture and integrated pest management (IPM). Their adoption strengthens local food security while demonstrating the seamless integration of Bt innovations within IPM-driven agricultural systems. A summary of Bt crops adoption among countries is shown in Table 8.

A reflection on the resourcefulness and permeability of biopesticides within the framework of Integrated Pest Management (IPM) underscores their pivotal role in sustainable pest suppression. As explained in previous sections, specific biochemical pesticides, including semiochemicals (e.g., sex pheromones, kairomones, and allomones) and plant-incorporated protectants (PIPs), pass through sophisticated technological process that remain largely beyond the reach of traditional technologies. Agriculture was central to the identity of early human civilizations, and traditional agro-technologies, such as the use of biopesticides, formed a core part of that culture. However, with current realities, societies that once celebrated biodiversity, farming, and food sufficiency are now re-evaluating the role and meaning of biopesticides. Ironically, biopesticides are now often perceived as novel or even foreign, prompting renewed efforts to raise awareness and promote their adoption. At the same time, agricultural technology (agrotech) is rapidly evolving, emphasizing both economic gain and ecological sustainability. This contrast suggests a historical disconnect, the nature of which remains open to investigation. It would be particularly interesting to determine whether this gap predates the Green Revolution, a pivotal era of agricultural change in the mid-20th century. While the Green Revolution significantly boosted global food production and addressed hunger in regions like India, Mexico, and Southeast Asia, it also introduced long-term environmental challenges such as soil degradation, water pollution, and pest resistance due to excessive chemical input use. Although the Green Revolution benefited many economically disadvantaged countries by enhancing food security, it also marked the beginning of unsustainable farming practices. Interestingly, prior to this shift, many of these regions seemed to employ eco-friendly subsistence farming methods. India, for example, has long been recognized for its abundance of neem, a plant celebrated for its pest control properties and medicinal value. In fact, disputes over biopiracy surrounding neem formulations highlight its deep-rooted significance in traditional agriculture. Given this context, claims such as that from Praneetvatakul et al. (2024), stating that “biopesticides are relatively new in agriculture, and lack of awareness may hinder their adoption, especially in developing and underdeveloped countries,” appear both controversial and debatable. These narratives often overlook the historical use of natural pest control methods in these regions. Rather than unfamiliarity with biopesticides themselves, it may be the modern, high-tech versions of agro-inputs that remain relatively unknown or inaccessible in these areas.

The paradox of biopesticide affordability vs. market dynamics stems from the contrast between their natural accessibility and the commercial dominance of advanced synthetic formulations. Biopesticides, derived from biological sources, have inherently low production and procurement costs, as many can be directly harvested, minimally processed, and applied effectively. Some biopesticidal agents, such as wild pesticidal plants, play a crucial role in strategies like the push-pull pest management system, where their natural repellency and attractant properties are leveraged without significant processing. Additionally, biopesticides can be used in crude or semi-formulated states, often demonstrating efficacy comparable to fully developed synthetic alternatives. Their extensive presence in Integrated Pest Management (IPM) frameworks, constituting over 50% of control strategies, highlights their compatibility and sustainability within eco-friendly agricultural practices. These advantages position biopesticides as a more cost-effective option than synthetic pesticides. However, despite these benefits, biopesticides remain at a pricing disadvantage due to factors such as limited production scale, shorter shelf life, and weaker distribution networks (Constantine et al., 2020), which hinder their accessibility and cost-effectiveness compared to synthetic pesticides. Bridging this gap requires strategic investment in infrastructure, policy incentives, and farmer education to enhance biopesticide affordability and competitive market positioning. While this gap persists, it would be constructive to classify biopesticides into two categories: “trado-tech” products, which are more affordable than synthetic pesticides, and high-tech products, which tend to be more expensive than their synthetic counterparts.

Even high-tech biopesticide products have the potential to be significantly cheaper than synthetic pesticides due to their simpler production processes. Unlike synthetic pesticides, which require complex chemical synthesis and petroleum-based raw materials, biopesticides are typically derived from naturally occurring microorganisms, plant extracts, or beneficial insect-derived compounds. Their reliance on renewable natural resources reduces both manufacturing costs and environmental impact. Additionally, biopesticides tend to be less toxic, leading to lower regulatory costs, simpler approval processes, and reduced safety requirements for handling and application (Mawcha et al., 2025a). These advantages contribute to their theoretical affordability. However, despite their cost-saving potential, biopesticides are frequently more expensive in practice. Limited production scale is one of the major reasons; many biopesticide manufacturers operate on smaller scales compared to large agrochemical companies producing synthetic pesticides, leading to higher per-unit costs. Furthermore, market penetration remains low due to various factors, including farmer hesitancy to adopt newer pest management strategies and a lack of awareness or education about their benefits. A shorter shelf life is another drawback; because biopesticides rely on living or naturally derived components, they often degrade more quickly, making storage and transportation more challenging and costly. In developing countries, weak distribution networks further hinder accessibility and affordability, as logistical inefficiencies drive up prices.

On the other hand, synthetic pesticides have dominated the market for decades, benefiting from well-established manufacturing infrastructure and economies of scale. Mass production allows synthetic pesticides to be produced in bulk, lowering costs. Their longer shelf life makes storage and transportation easier, ensuring availability over extended periods. Established trust within the agricultural sector also plays a role; farmers and agribusinesses are more likely to choose synthetic pesticides due to their familiarity and predictable results. Additionally, synthetic pesticides often receive substantial government and industry support, whether through subsidies, research funding, or distribution partnerships, further strengthening their cost competitiveness (López de Mesa, 2020). This situation creates a market paradox where a product (biopesticides) that is theoretically cheaper to produce ends up being more expensive to purchase and use. To address this gap, several measures are needed. Expanding production infrastructure and scaling up manufacturing will help reduce costs by improving efficiency. Greater investment in distribution networks and supply chains can enhance accessibility, especially in regions where biopesticides remain underutilized. Farmer education and awareness campaigns can encourage adoption by demonstrating their effectiveness and long-term benefits, including improved soil health and reduced environmental contamination. Finally, supportive policies, such as subsidies for biopesticide production or incentives for farmers to transition to eco-friendly pest management, could create a more level playing field. Ultimately, bridging the cost gap between biopesticides and synthetic pesticides requires coordinated efforts across research, industry, policy, and education. With increased adoption and investment, biopesticides could become more cost-effective, making sustainable and environmentally friendly pest control solutions a viable option for farmers worldwide. Research efforts should be strategically aligned to address these knowledge gaps until the cost of biopesticide formulations becomes economically competitive with that of synthetic chemical pesticides.

Biopesticides occupy a critical yet underutilized niche in modern agriculture, especially within Integrated Pest Management frameworks. Although rooted in traditional agro-technological practices, their contemporary iterations are often misconstrued as novel, overshadowed by the industrial dominance of synthetic pesticides. The paradox of their theoretical affordability and practical inaccessibility reflects systemic challenges, including limited production scale, short shelf life, and weak distribution networks, that inhibit their widespread adoption, particularly in developing countries. Addressing these barriers will require a multipronged approach: expanding manufacturing capabilities, strengthening supply chains, implementing policy incentives, and promoting farmer education. While efforts are underway to address the limitations of biopesticides, low-tech technologies such as botanical extracts, pesticidal plants (RBT plants), and entomopathogenic nematodes (EPNs) can be relied upon by farmers to achieve significant success. This transformation is essential not only for enhancing agricultural productivity but also for ensuring long-term environmental resilience and food security. By bridging historical knowledge with modern agrotechnology and aligning efforts across research, industry, and policy, the full potential of biopesticides as sustainable, cost-effective pest control agents can be realized.