Whitefly
From Free net encyclopedia
{{Taxobox | color = pink | name = Whitefly | image = Weisse-Fliege.jpg | image_width = 240px | image_caption = Whiteflies | regnum = Animalia | phylum = Arthropoda | classis = Insecta | ordo = Hemiptera | subordo = Homoptera | familia = Aleyrodidae }}
The whiteflies, comprising the family Aleyrodidae, are small homopterans which feed on the underside of plant leaves. When you tap the leaf, a swarm of flies will cloud before re-settling under the leaf. Whiteflies damage plants when they feed upon the phloem. The plants lose turgor and react to the flies' toxic saliva. As whiteflies congregate in large numbers, they overwhelm plants quickly. They also excrete honeydew, which promotes mold growth and can ruin a cotton crop with its stickiness.
One well known species is the greenhouse whitefly (Trialeurodes vaporariorum) which is a major pest in greenhouses but there are other pest species such as the bandedwinged whitefly and the silverleaf whitefly.
Whitefly control is difficult. The greenhouse whitefly has developed resistance to many pesticides. The USDA recommends "an integrated program that focuses on prevention and relies on cultural and biological control methods when possible." [1] They advise use of yellow sticky traps to monitor infestations and only selective use of insecticides.