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Adult greenhouse whiteflies measure about 2 mm and are covered
with a white waxy powder. Their wings are positioned horizontally
and overlap slightly. The female greenhouse whitefly deposits its
oval-shaped eggs of 0,2 mm on the underside of leaves at the top
of the plant. After 2 - 3 days they turn black.
The larva that hatches is first mobile during a few hours to search
for a suitable place on the leaf to settle. Later on, and in the
subsequent larval stages and pupal stage, it does not move anymore.
The four larval stages look very similar, but differ clearly in
size.
The white, transparent pupa is round with an upright edge. The pupa
is covered with hairs.
An adult greenhouse whitefly emerges from the pupa through a T-shaped
exit hole.
On tomato, development from egg to adult takes 20 days at 27°C
or 38 days at 17°C, but on other host plants this can be quite
different.
Also fertility depends on temperature and host plant. A female lays
about 100 eggs on tomato, 200 eggs on cucumber and 300 eggs on eggplants.
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