Identification of major parasitoids and predators used in biological control is a key aspect of integrated pest management (IPM). These natural enemies help control pest populations by parasitizing or preying on them, providing an eco-friendly alternative to chemical pesticides.

1. Predators

Predators are organisms that kill and consume multiple prey during their lifetime. Many of the major predators used in biological control are insects, which help control various pests in crops.

• Lady Beetles (Coccinellidae): Species: Hippodamia convergens, Coleomegilla maculata. Target Pests: Aphids, scale insects, mites, and small caterpillars. Significance: Lady beetles, particularly their larvae, are voracious aphid predators and can also feed on other small insects.
• Hoverflies (Syrphidae): Species: Syrphus ribesii. Target Pests: Aphids. Significance: The larvae of hoverflies can consume up to 400 aphids in their lifetime, making them effective natural enemies in managing aphid populations.
• Predatory Mites: Species: Phytoseiulus persimilis, Neoseiulus californicus, Amblyseius cucumeris. Target Pests: Spider mites (e.g., Tetranychus urticae). Significance: These mites actively hunt and consume pest spider mites, thus controlling mite infestations in crops.
• Entomopathogenic Nematodes: Species: Steinernema spp., Heterorhabditis spp.. Target Pests: Soil-borne insect pests (e.g., root weevils, soil-dwelling larvae). Significance: These nematodes enter the host insect, where they release symbiotic bacteria that kill the host. They are particularly useful for controlling soil-dwelling pests.
• Predatory Bugs (Hemiptera): Species: Orius insidiosus (minute pirate bug), Geocoris spp. Target Pests: Thrips, aphids, whiteflies, and other small insect pests. Significance: These bugs feed on a wide range of pest insects and help keep pest populations in check.

2. Parasitoids Parasitoids lay their eggs on or inside the bodies of insect hosts. The larvae feed on the host, ultimately killing it. Parasitoids are often highly specific to their hosts, making them effective in controlling pest species without harming other beneficial insects.

• Ichneumonid Wasps (Ichneumonidae): Target Pests: Caterpillars, beetle larvae. Significance: These wasps lay their eggs inside the body of caterpillars, and the emerging larvae feed on and kill the host. They are important in controlling pests such as caterpillars in crops.
• Braconid Wasps (Braconidae): Target Pests: Caterpillars, aphids, whiteflies, and other pests. Significance: Braconid wasps are highly diverse and parasitize a wide range of insect pests. For example, Aphelinus abdominalis parasitizes aphids, and Microplitis croceipes targets caterpillars.
• Chalcid Wasps (Chalcididae): Target Pests: Eggs and larvae of insect pests. Significance: Chalcid wasps parasitize the eggs and larvae of various insect species. For example, Trichogramma spp. parasitize the eggs of moths and butterflies, helping control pest populations.
• Tachinid Flies (Tachinidae): Target Pests: Caterpillars, beetles, true bugs. Significance: These flies parasitize a wide range of insect pests. Their larvae hatch inside the host, feeding on its tissues until the host is killed. They are effective in controlling caterpillar populations.
• Encarsia Formosa (Encarsia spp.):  Target Pests: Whiteflies (e.g., Trialeurodes vaporariorum). Significance: This parasitoid wasp is commonly used in greenhouse environments to control whitefly infestations. It parasitizes the immature stages of whiteflies.

3. Other Biological Control Agents

• Predatory Mites for Mite Control: Phytoseiulus persimilis for controlling spider mites.
• Parasitoid Wasps for Whitefly Control: Encarsia formosa for controlling whiteflies.

Key Factors for Effective Use:

• Target Pest: Identifying the correct natural enemy for the specific pest is crucial.
• Environmental Conditions: Natural enemies thrive under certain environmental conditions, so timing and placement are essential for successful control.
• Monitoring: Regular monitoring is necessary to track the effectiveness of the biological control agents and make adjustments if needed.