Biological control of tarsonemid mites in greenhouse grown gerberas

Abstract: Several species of Phytoseiidae were evaluated as predators of Tarsonemus violae(Schaarschmidt) and the broad mite Polyphagotarsonemus latus (Banks) on gerbera plants inexperimental and commercial greenhouses. Amblyseius cucumeris, A. swirskii, Typhlodromipsmontdorensis and A. andersoni appeared to possess the best abilities to control tarsonemids inthis crop. These species displayed good survival and reduced mite densities at low levels directlyafter their releases. However, curative strategies did not effectively eliminate tarsonemids and thepredators could not keep pests density below economic damage threshold year round withoutfurther releases.