Iolinid mites against powdery mildew and russet mites in tomato protected crops

Abstract: The mites Homeopronematus anconai (Baker) and Pronematus ubiquitus
(McGregor) (Acari: Iolinidae) are common predators in berries and can occur spontaneously
on tomato plants, where other commercially available predatory mite species fail to establish.
This study on H. anconai was initiated to improve biological control of tomato russet mites
using either mite. The species rapidly reached high densities when pollen was supplied. It
showed potential to control not only russet mites but also powdery mildew. Different
greenhouse trials showed later on that both Tydeoids do so. This paper provides an overview
on the current status of commercial biological control using iolinids mites against powdery
mildew, from the first results showing powdery mildew control in tomato up to recent trials in other areas. Factors affecting the efficacy of iolinids in greenhouse crops are discussed.