Aged-residue method for evaluating toxicity of plant protection products to Stethorus punctillum (Weise) (Coleoptera: Coccinellidae)

Stethorus punctillum (Weise) (Coleoptera: Coccinellidae) is known as an obligate predator of spider mites. Currently there are no widely recognised laboratory methods for testing the effects of plant protection products (PPP) to this species. Here we present a method for evaluating the toxicity of PPP under extended laboratory conditions or as a persistence (aged residue) study, combining field applications with laboratory bioassays. S. punctillum larvae were exposed to treated apple leaf disks and their development through to pupation and adult emergence monitored. An assessment of reproduction was also performed. Example data corresponding to control, methoxyfenozide and fenoxycarb treatments are presented.