ELEMENTAL MARKING OF ARlHROPOD PESTS IN AGRICULroRAL SYSTEMS: SINGLE AND MULnGENERAnONAL MARKING

Use of elemental markers to study movement of arthropod pests of field crops is reviewed. Trace elements, rubidium (Rb) and cesium (Cs), have provided a nondisruptive method of marking natural adult populations via developmental stage consumption of treated host plants. Multigenerational marking occurs with the transfer of elemental markers from marked adults to reproductive products, including eggs, egg masses, and spermatophores. For highly mobile insects such as Lepidoptera, recovery of marked eggs is superior to the more typical recapture of marked adults. Preliminary studies required to refine marking and detection techniques are described, and results of ongoing field studies of meso-scale movement in Heliothis virescens (F.) and Helicoverpa zea (Boddie) using elemental marking and recovery of eggs are reported. Additionally, the problem of mark variability is discussed.