Biological pest control It is an essential technique and increasingly widespread both in agriculture, gardening and urban spaces for offering ecological and sustainable alternatives to the use of chemicals. Thanks to this method, it is possible to manage organisms that damage crops, gardens, and environments, using other living beings that act as specific natural enemies of the target pests.
In addition to its agricultural and livestock use, biological control has been successfully transferred to homes, parks, urban green areas and even greenhouses and nurseries, adapting to different needs and contexts. This strategy allows reduce the use of chemical pesticides, protect human health and preserve the natural balance of ecosystems.
If you are looking for an effective, safe and environmentally friendly solution, get to know it in depth. how biological pest control works and what their applications, advantages, limitations, and real-life examples are, is essential. This article compiles all the relevant information, integrating the latest trends and insights in the sector.
What is biological pest control?
El biological pest control, also known as biocontrol, is a strategy that employs living organisms —predators, parasitoids, or pathogens—to manage pest populations and keep their levels below the economic threshold of harm. In essence, this method mimics natural ecosystem processes to restore balance between predators and prey, minimizing the environmental impact.
Compared to the traditional approach based on phytosanitary products, biological control focuses on selectivity and coexistenceBiological control agents are typically species that naturally keep specific pests at bay without endangering biodiversity or contaminating natural resources. Ladybugs, lacewings, parasitoid wasps, entomopathogenic bacteria, fungi and viruses are just some of the main protagonists in this natural struggle.
The responsible use of biological control has a positive impact on soil health and crop resilience, as well as curbing the development of resistance, an increasingly common problem with conventional pesticides.
How biological pest control works
The fundamental principle of biological control lies in taking advantage of the natural relations of antagonism between organisms: some species act as natural enemies of others. The mechanism is based on the introduction or enhancement of biological agents (predators, parasitoids, or pathogens) that attack, parasitize, infect, or displace the main pest from the environment.
Its implementation usually follows these steps:
- Identifying the type of pest and understanding of its life cycle.
- Selection of the biological control agent more effective and specific for the target pest.
- Introduction (or natural promotion) of these organisms in the environment where the pest thrives.
- Monitoring and tracking of the results, evaluating the evolution of populations of both the pest and the control agent.
- Maintenance and conservation of the favorable conditions to ensure the continued action of the useful agent.
Unlike pesticides, biological agents They do not usually completely eliminate the pest, but rather stabilize their population at non-harmful levels, avoiding cycles of resurgence and the emergence of resistance.
Types of biological pest control
Biological control can be classified into various modalities according to its implementation strategy:
- Classical or imported biological control: It consists of the introduction of exotic natural enemies (not originally present in the ecosystem) to combat invasive or foreign pests. Example: the introduction of the beetle Rhodolia cardinalis to control the ribbed scale in citrus fruits.
- Augmentative or incremental biological control: It is about increasing in a way artificial population of beneficial agents through periodic or massive (flooding) releases into the crop. It is common in greenhouses and high-value crops.
- Biological conservation control: Power the natural presence of native enemies in the agroecosystem, improving their living conditions (shelters, hedges, nectariferous plants, reduction of pesticides) to prevent future infestations.
The choice of treatment method always depends on the type of pest, the crop, the environment, and the long-term objectives.
Classical biological control: restoring balance against invasive species
Used especially against exotic pests, classical control has proven to be very effective in cases such as the fight against corrugated mealybug In citrus groves, where highly selective foreign predators were introduced. Success lies in in-depth prior research to ensure that the introduced agent does not negatively alter the local ecosystem.
Augmentative biological control: intensive reinforcement of beneficial agents
In this approach, they are released large amounts of beneficial organisms (e.g. Trichogramma wasps or ladybugs) at two key moments:
- Inoculative releases: small amounts at the beginning of the cycle so that the agent can establish itself and multiply.
- Flood releases: large quantities for immediate and effective control in times of high pest pressure.
Biological conservation control: enhancing the native
The most sustainable strategy: create a favorable habitat for native natural enemies, such as ladybugs, lacewings, and beneficial spiders. Maintaining hedges, planting flowers and herbs, and minimizing pesticides provides shelter, food, and reproduction for these natural allies.
What organisms are used in biological pest control?
In biological control they are mainly used three large groups of organisms:
- Predators: They actively feed on the pest. Examples: ladybugs (Coccinellidae) against aphids, lacewings against thrips and mites, predatory mites for pest mites, beneficial spiders or insectivorous birds.
- Parasitoids: They lay their eggs in or on the body of the pest, and the larvae feed on it, eventually causing its death. Examples: Trichogramma wasps against moth eggs, Aphelinus abdominalis against aphids, or parasitoid flies.
- Pathogens: Microorganisms that infect and make sick to the plague. They stand out bacteria (as Bacillus thuringiensis against caterpillars), entomopathogenic fungi (beauveria bassiana, Metarhikum anisopliae for insects), and virus (baculovirus against larvae).
Some agents, such as certain entomopathogenic nematodes, are also used in specific crops. And we must not forget the role of allelopathic plants, which emit natural compounds that repel pests or attract natural enemies.
Outstanding examples of biological control in agriculture and gardening
- encarsia formosa against whitefly on tomatoes and peppers under greenhouse conditions.
- Ladybugs (adults and larvae) for the control of aphids in vegetables and ornamentals.
- Bacillus thuringiensis to combat defoliating caterpillars in corn, brassica and fruit fields.
- Lacewings to stop populations of thrips, aphids and mites in orchards and gardens.
- Entomopathogenic fungi for the control of soil and foliage insects.
Applications of biological control in different crops
Biological control adapts to various types of crops:
- Horticultural crops: Tomatoes, peppers, cucumbers and strawberries use a combination of parasitoids, predators and fungi in greenhouses and open fields to control whiteflies, aphids and red spiders.
- Extensive crops: Corn, rice and wheat take advantage of bacteria such as Bacillus thuringiensis and the conservation of hedgerows to encourage native predators.
- Fruit trees and vineyards: Use of lacewings and parasitoid wasps to reduce mealybugs, moths, and aphids on citrus, vines, and fruit trees.
- Gardening and urban areas: Releases of ladybugs and predatory mites or application of natural fungi in parks, gardens, and nurseries.
- Greenhouses: Controlled environments where biological control is essential to prevent the accumulation of chemical waste.
Benefits of biological pest control
- Reducing the use of chemical pesticides: Reduces toxic waste in products, soil and water.
- Biodiversity conservation: Protects pollinators, auxiliary fauna and beneficial microorganisms.
- Preventing resistance in pests: The diversity of biological mechanisms slows the development of resistance.
- Safety for farmers and consumers: Less exposure to hazardous substances, better overall health.
- Improving soil health and crop resilience: Promotes a balanced diet and reduces plant stress.
- Medium and long-term economic sustainability: The initial cost of implementation is offset by savings in pesticides and crop stability.
Challenges and considerations when applying biological control
While biological control is highly advantageous, its success depends on several factors:
- Need for technical knowledge: Accurate identification of pests and natural enemies is key. Training is required to select the appropriate agent and its optimal release timing.
- Constant monitoring: It is essential to regularly monitor the balance between pest and control agent, assessing possible unwanted effects.
- Less immediate results than chemicals: The impact is usually gradual and requires patience, especially in open systems.
- Risk of affecting non-target species: The introduction of exotic species must be carried out after a thorough study of environmental risks.
- High initial cost: A higher investment may be required in the early years, especially for mass releases or pre-studies.
Biological control is often integrated into a integrated pest management (IPM), combining biological, cultural and, only ultimately, highly selective chemical techniques.
Complementary techniques and integrated strategies
Biological control techniques do not act alone. To ensure their success, they should be accompanied by other cultural and preventive methods:
- Crop rotation and plant diversification.
- Proper irrigation and nutrient management to avoid stress and weakness in plants.
- Manual or mechanical elimination of initial pest foci.
- Installation of hedges, plant strips and auxiliary insect shelters.
- Use of sexual confusion pheromones and traps for monitoring.
In certain crops, the use of pheromones, plant extracts and color traps effectively complements the action of biological agents.
Relevant success stories in biological control
There are outstanding examples of success that support the role of biological control:
- The use of Encarsia formosa wasp has made it possible to drastically reduce the presence of Whitefly in greenhouse tomato and pepper crops in different regions.
- The introduction of Rodolia cardinalis beetle to fight the corrugated mealybug It changed the citrus landscape and is considered one of the most successful and long-lasting biological controls worldwide.
- In the cultivation of strawberry, the release of lacewings and other predators has reduced dependence on pesticides and improved crop quality.
- En corn and other extensive crops, the continued use of Bacillus thuringiensis has allowed the control of caterpillars with minimal residue and without affecting pollinators.
These examples demonstrate that, when properly planned and tailored to each situation, biological control can deliver sustainable results, contributing to cleaner, more profitable, and safer production.
