Chapter 3.2 Damage and control of eriophyoid mites in crops 3.2.1 Stylar feeding injury and control of eriophyoid mites in citrus

Abstract

This chapter describes the various citrus plant alterations caused by eriophyoid mite feeding and relates plant injury to current control practices respective to species. According to Jeppson and coworkers, seven vagrant species infest citrus and injure plant tissues via stylar feeding: the citrus rust mite (CRM), the citrus bud mite (CBM), the pink citrus rust mite, the brown citrus mite, the citrus blotch mite, Cosella fleshneri , and the citrus leaf vagrant. Visible characteristics of injury differ according to citrus variety and the maturity of fruit. When CRM injury occurs on fruit during the exponential growth phase before fruit maturity, further growth leads to a breaking up of the dead epidermis and subsequent wound periderm formation beneath the epidermis. Cracks develop in the epidermis, but the epidermal layer does not break up into separate patches. The cracks result in a rough texture that cannot be polished, while the oxidized cell contents give the fruits their brownish-black color. This early season CRM injury is defined as “russet” condition.