Parasites for Control of Aphids
Aphid parasite: Aphidius colemani
For green peach and melon aphids. Aphidius colemani is a small parasitic wasp that lays its eggs in aphids. The eggs hatch inside and the larvae spin cocoons which swell the aphid's body. The adult wasp then exits the aphid body, leaving behind a hard brown shell called an aphid mummy. Larval development takes 2 weeks at 21° C. (70° F.). These wasps do not diapause, and in fact are most effective from September -March because their own parasites are not present. Used with Aphidoletes in greenhouse peppers in Canada.
Optimal Environment: 50-76°F. Tolerates cool temp., low light.
Aphid parasites: Aphidius ervi and Aphelinus abdominalis
Tiny parasitic wasps that are unique in their ability to control potato aphids and greenhouse potato aphids.
Predators for Control of Aphids
Aphid Predatory Midge: Aphidoletes aphidimyza
This delicate midge produces orange larvae that feed on aphids. Females lay
100-200 tiny orange eggs near aphid colonies. Each larva kills from 4-65 aphids.
The short days of winter can cause diapause (dormancy) - prevent by supplemental
lighting (one 60 watt bulb per 30 feet, or 100 watt bulb per 65 feet).
Optimal Environment: 73-77°F, OK to 60°F; 80-90% RH.
Lacewings: Chrysoperla rufilabris
Lacewings are general predators: aphids are the main prey, but they also
feed on mealybugs, scales, spider mites, thrips, and small caterpillars. The
adult is 1/2-3/4 in. long, green or light brown, and has large clear wings with
lacy markings. The larvae are voracious predators known as aphid lions, and
look like small, mottled alligators. A single aphid lion will consume 200-300
aphids. Lacewing eggs are light green and elevated on tall slender stalks, but
lacewings almost never reproduce in the greenhouse.
Optimal Environment: 60-80°F.
Field-collected Ladybeetles: Hippodamia convergens
Ladybeetles are general predators that prefer aphids, but will also feed
on scales, thrips, and small caterpillars. They are expecially attracted by
aphids. Adult females lay clusters of orange, bullet shaped eggs on the underside
of leaves, but only near heavy aphid infestations. Adults can consume 5000 aphids
each during their lifetime. One pint contains approximately 9,000 ladybeetles
Optimal Environment: 61-82°F, OK to 55°F.
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