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Preserving Beneficial Predators in the Home Garden. Mary Barbercheck and Jermaine Hinds Penn State Department of Entomology. Principles of IPM. Manage system for productivity and beneficial processes Plant Positive vs. Pest Negative
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Preserving Beneficial Predators in the Home Garden Mary Barbercheck and Jermaine Hinds Penn State Department of Entomology
Principles of IPM • Manage system for productivity and beneficial processes • Plant Positive vs. Pest Negative • Use of decision-making criteria before action (or no action) • Integration of all suitable control techniques in a compatible manner • Limited pesticides, only as last resort Ladybeetle and Syrphid on Buckwheat Flowers
What are Natural Enemies? • Predators • Parasitoids • Pathogens Value of pest suppression estimated at $6 billion per year! Predatory Mite Ground Beetles Damsel Bug Insect-parasitic Nematode Insect-parasitic fungi Parasitic Wasps Spiders
Natural Enemies of Plant-Feeding Insects Predators – during development consume many insects Predatory mites, ground beetles, predatory bugs, spiders, daddy-longlegs, centipedes
Natural Enemies of Plant-Feeding Insects Parasitoids – during development consume one insect • parasitoid wasps, tachinid flies
Natural Enemies of Plant-Feeding Insects Pathogens - cause disease in host organism • fungi, bacteria, viruses, protozoa, nematodes
Biological Control Biological Control - Exploitation of natural enemies to hold pests below economically damaging levels Conservation • Improve environment for existing beneficial organisms Augmentative & Inundative • Purchase and release • Usually not long-term • Improve environment for applied beneficial organisms Pediobius wasp on Mexican Bean Beetle Aphid “mummies”after parasitoid emergence
Conservation Biological Control • Goal: Improve environment for beneficial organisms and processes • Habitat Management: provide resource plants or habitats, e.g., • cover crops • refuge strips of flowering plants • pollen and nectar resources required by many insect natural enemies
Minimize Disturbance Excessive tillage and pesticides may threaten and disturb beneficial insects • Destroy habitat • Directly kill insects Insects use undisturbed areas for foraging, refuge and overwintering Provide areas free of disturbance Conservation borders/strips: Hedgerows, perennial wildfllower strips, etc
Choosing the right plants Compatible with growing system Diversify! • Variety of flower colors, shapes and sizes • Choose different flower structures, tall an short • Choose species that ensure bloom throughout the growing season
Caution Pesticide Use Pesticides may harm beneficial insects! • Avoid spraying when insects are active • Pesticides should be used as a last resort • Rely on cultural and biological control measures • Use targeted/ least toxic pesticides
Some “Soft” Pesticides Safest • Insecticidal soap • Diatomaceous earth • Spinosad(Entrustr) • Various microbials • Particle films: bentonite, kaolinite(Surroundr) • Plant extracts and oils • Pheromones OK • Dormant and summer oils (narrow range petroleum, fish, plant) • Sulfur compounds • Botanicals • Pyrethrum (PyGanicr) • Neem
Considerations for pesticide use • Have a plan: How and when you will react to a pest outbreak • Decide in advance your‘action threshold’ • Where possible, use biological controls • Know your soft pesticide choices: what’s safe, what’s labeled, what works, cost. European Corn Borer Flea beetle
Microbial Controls • Insect Control: • B.t.varkurstaki • Beuveria spp. • (Mycotrol, Naturalis) • Metarhizium spp. (Met52) • Insect viruses Beauveria Insect Virus
Minimize Pesticide Non-target Effects • Kaolin clay particle film • Registered on a variety of fruits and vegetables • Prevents insect feeding and oviposition • Approved for organic production
Biological Control of Pests: Augmentative • Apply large number of organisms in same manner as a pesticide • Introduces large numbers of organisms for relatively fast-acting control • May or may not become established
Summary Beneficial insects: • Important for pest suppression! • Require undisturbed and resource-rich habitat to thrive How to conserve? • Minimize disturbance • Provide resources Food (nectar, pollen) Foraging sites Overwintering sites • Minimize pesticide use • Rely on cultural and biological methods of control