Biological Solutions

The wasp genus Aphidius is a large group containing numerous species, all of which attack aphids and provide natural control of aphids in backyard gardens, commercial fields, and urban landscapes. They are generally used in greenhouses.
Aphidius colemani are small braconid wasps. Females lay eggs singly in aphid nymphs. The wasp larvae consume the aphids from inside. As the larvae mature and the aphids are killed, the aphids turn into mummies. After the larvae pupate, each adult wasp emerges through an exit hole cut in the mummy. In addition to killing aphids directly, mechanical disturbance of aphid colonies by the searching behavior of the adult wasps causes many aphids to fall off the plants and die.

Red Scale Parasite (Aphytis melinus) California red scale is the favorite prey of these parasitic wasps, although citrus red scale, oleander scale, San Jose scale, ivy scale, and citrus yellow scale are other prey. Aphytis are shipped as adults, and the adult females lay their eggs in red scale. The larvae consume their host, and each A. melinus kills more than 30 scale insects.

Aphidius ervi attack many species of larger aphids such as the green peach aphid and brassica aphids.

A relatively large wasp (twice the size of Aphidius colemani) with a black, slender body with brown legs and long antennae. The female wasp injects an egg in the aphid with her ovipositor. Hatched larvae eat the aphid from the inside leading to the formation of a a golden-yellowish-brown mummy. Finally, a new adult parasitic wasp leaves the mummy through a round hole.

C. montrouzieri is a voracious feeder of mealybugs in both the larval and adult stages - a single larva may consume up to 250 small mealybugs.

These small wasps parasitize leafminer larvae in field and greenhouse crops. The parasitic wasp lays its eggs in or next to leaf miner larvae of the second and third instar. Diglyphus isaea kills leaf-miner larva in the mine and lays an egg on it. The egg develops into a parasitic wasp inside the mine (but outside the leaf miner), using the dead larva as food. Host-feeding also takes place. The young parasite larvae hatch from these eggs, and will then feed on the body fluids of the larvae. Duration of development; egg-adult, at 68ºF (20ºC) ± 16 days.