|Freeman, Thomas - NORTH DAKOTA STATE UNIV|
Submitted to: International Entomophagous Insect Workshop
Publication Type: Abstract Only
Publication Acceptance Date: December 12, 2000
Publication Date: N/A
Technical Abstract: Some adult insects produce copious amounts of waxy particles immediately after emergence. Adults spread these waxy particles over all parts of their body, except for their eyes. The waxy particles are formed by specialized wax. The Aleyrodinae, e.g., the silverleaf whitefly, Bemisia argentifolii, and the greenhouse whitefly, Trialeurodes vaporariorum, form near-circular particles about 1 micrometer in diameter; the Aleurodicinae, e.g., the giant whitefly, Aleurodicus dugesii, form waxy fragments 10-30 micrometers in length and 2-2.5 micrometers in width. Particles are formed as the adult rakes its tibia across extruding waxy filaments breaking them off. Copious amounts of waxy particles are also dislodged from the insect, covering nymphs and surrounding leaf surfaces. The adult dustywing, Semidalis flinti, is a predator of whitefly eggs and nymphs which forms circular waxy particles about 1 micrometer in diameter. These particles are formed by numerous specialized pores, rosette-like in appearance, on the abdomen. Each pore extrudes dual waxy ribbons. As the ribbons extend beyond the pore, the ends curl back to make contact with the ribbon and form a circle. The curled end breaks free from the extruding ribbon to form circular waxy particles which the adults use to cover all parts of their body except for their eyes. The lipid portion of the circular waxy particles from S. flinti consisted largely of a 24-carbon fatty acid, tetracosanoic acid, with lesser amounts of hydrocarbons and fatty alcohols. In comparison, the waxy particles found on adult whiteflies are composed of a mixture of long-chain aldehydes and long-chain alcohols: the major components had carbon chain lengths of 30 for A. dugesii, 32 for T. vaporariorum, and 34 for B. argentifolii and B. tabaci.