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Common Names: Eulophid Wasp, Whitefly Parasite

Scientific Name: Order Hymenoptera, family Eulophidae, Encarsia formosa

Size: Less than 1/25"

Identification: Adult wasps have a black head and thorax and yellow abdomen.

Biology and Life Cycle: Females lay fifty to one hundred eggs singly in whitefly nymphs. Parasitized whitefly nymphs turn black. Sweet potato whiteflies turn brown. Small wasps the size of a pinhead emerge from mature whitefly nymphs through a small hole. Complete metamorphosis.

Habitat: Greenhouses. This species cannot survive cold winters.

Feeding Habits: Adult whitefly parasites also kill whitefly nymphs by direct feeding. Eggs hatch into larvae inside whitefly nymphs.

Economic Importance: Control of whiteflies and aphids. They are most effective at 65-80°F with high light intensity and relative humidity of 50-70 percent.

Natural Control: None needed--beneficial insect.

Organic Control: None needed.

Insight: Whitefly parasites can help control pests that cause serious damage to tomatoes, cucumbers, and ornamental plants. They attack the whitefly in its immature stages, laying eggs in the third and fourth stages while feeding on the first and second stages. Early, preventative applications of Encarsia formosa prior to heavy infestations is recommended. They are expensive and should only be used as part of an overall organic program.

Widespread spraying of pyrethroids and other synthetic toxic pesticides on cotton crops has destroyed this beneficial natural control and cost the farming industry millions of dollars. Use one to five insects per square foot of plant area, one to eight per plant in greenhouses. There are several other species of Encarsia that are effective in field crops.


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