Samira Khodayari

Spider mites (family Tetranychidae) are important pests of many agricultural, medicinal and ornamental plants worldwide. They possess needle-like chelicerae which pierce plant cells, often feeding on chloroplasts on the under surface of the leaf and cause upper leaf surfaces develop whitish or yellowish stippling. Additionally spider mites produce silk webbing which covers the leaves. In this chapter we present common control methods of these mites including biological control with emphasizing on the prey preference, switching behavior and mutual interference of a biological control agent, Phytoseius plumifer (Canestrini and Fanzago). Additionally the side effects of two acaricides, abamectin and fenpyroxymate, on this predator will be discussed.