PEST
 
   NAME
     Greenhouse or Black Thrips
     Heliothrips haemorrhoidalis
 
   ORDER
     Thysanoptera
 
   FAMILY
     Phlaeothripidae

Description of the Pest
The adult is up to 1.5mm long and is dark brown to black with the end of the abdomen being lighter in colour and having feathery wings and rarely flies. The tiny nymphs are lighter in colour and both adult and nymph have rasping and sucking mouthparts.

Life Cycle
This insect has a Hemimetabolous life cycle, ie. When the immature nymphs resemble the adults.
There are 4-nymphal stages with the first two on the plant and the last two in the soil or in leaf litter, where it is non-feeding.

Period of Activity and Distribution of the Pest
This pest is distributed world wide preferring hot dry weather in a shady cool position with some moisture and is active in the warmer months of the year. 

Susceptible Plants
This pest attacks a wide range of ornamental plants in including Fuchsia, Azalea (Rhododendron species) Viburnum, Cissus, Liquidambar, Vitis (Grapes), Passiflora (Passionfruit) species, Persimmon and Prunus species.

Morinda citrifolia is attacked by the greenhouse thrip (Heliothrips haemorrhoidalis) which is parasitic on noni leaves.

 Morinda citrifolia

Damage Caused
The adult and two first nymphal stages cause the damage by rasping and sucking plant tissue by forming colonies on the underside of the leaf. The leaf surface has a characteristic silvering appearance with blobs of excrement that are black or brown. The pest is also found between overlapping leaves where it attacks the underside and upper layer of the leaf.

Cultural control 
The infected plant may be sprayed with a soapy spray particularly on the underside of the leaves.

Biological control 
A parasitic wasp may reduce the numbers.

Chemical control 
The affected plants may be sprayed with insecticide including a systemic (Dimethoate) or contact (Maldison). Two applications are required with a 10 day spacing to allow newly hatched nymphs and resting adults that are found in leaf litter to emerge onto the plant.
Note
Always read the label for registration details and direction of use prior to application of any chemicals.