Encarsia formosa, EN-STRIP

Encarsia formosa

Female with thorax and head black-dark brown, abdomen yellow. Male totally black, male is rare.The parasitoid is around 0,6 mm in size. All developmental stages (except adult stage) live within the host's body (whitefly larva). About halfway the total development of the parasitoid the pupa of the greenhouse whitefly host turns black. When a tobacco whitefly is parasitized the pupa turns brown.

Encarsia formosa

Mode of action:

prefers 3rd and 5th whitefly instars for egg laying. Smaller stages of whitefly are preyed upon for host-feeding. This preying contributes considerably to the control activity of the parasitoids. Parasitization of Encarsia formosa is seriously hampered when large amounts of honeydew are present; a leaf surface with lots of haires has a negative influence on parasitization activity activity of Encarsia formosa.


EN-STRIP is being used in greenhouse crops as well as indoor plantscapes against greenhouse whitefly and tobacco whitefly. Consider repeated introductions. The product is sensitive towards chemical pesticides. Ask advice for an optimal introduction strategy.

Effect of EN-STRIP:

  • first pupae appear 203 weeks after introduction
  • parasitized whitefly larvae turn black or brown
  • greenhouse whitefly turns black, tobacco wjhitefly turns brown
  • young adult hatches through a round exit hole
  • adult parasitoids feed themselves from host larvae, so called host-feeding
  • sucked dead larvae remain on the underside of the leaves

The product EN-STRIP:

Product: parasitized whitefly pupae glued on cardboard cards. In total around 3000 parasitoids will hatch from the cards.

Shelf life: maximum 2 days at 8-10°C  in the dark

Climate: optimal conditions for Encarsia formosa are 20-25°C, minimum temperature is 12°C. Short day lenghts and low light intensity have a negative influence on their activity. 

Targets EN STRIP:

  • greenhouse whitefly
  • tobacco whitefly