Adult thrips are about 1.5 mm, females slightly larger than males. The body is dark colored with a lighter section at the end. They have light-colored legs, antennae are also light in color. The wings are light in color with a somewhat darker band in the longitudinal direction, wings form a light band in the longitudinal direction of the thrips. The larvae are yellow, with light-colored legs and antennae. Characteristic for the black greenhouse thrips are the dominating dark-colored droplets that they carry long period of time at the end of their body. Over time they fall off and remain sticked on the leaf surface as small black spots.
Damage and distribution in the crop:
They are mainly leaf dwelling species. Adult thrips often sit on the upperside of the leaf while larvae sit together in groups on the underside. Both larvae and adults are not very mobile. When disturbed they run away but they are generally found sitting quiet close to each other on the leaves. The damage from the black greenhouse thrips consists of silver-gray spots on the leaves which contain black dots of excrement of the thrips. In case of a heavy infestation they scrape the whole leaf surface so the leaves will dry out and fall off. In some crops, they can occur on fruits where they cause necrotic spots.
lifecycle black greenhouse thrips:
- eggs in the leaf, covered with small 'cap'
- mainly females, males rare
- parthenogenetic reproduction
- female lays about 50-70 eggs
- Development time: 35-40 days
- female lives 30-40 days
- several generations per year
host plants black greenhouse thrips;
- rather polyphagous
- mainly subtropical host plants
Products against greenhouse thrips: