The biological control of Kelly’s citrus thrips in Australian citrus orchards
Abstract: Kelly’s citrus thrips (KCT) (Pezothrips kellyanus (Bagnall)) (Thysanoptera:Thripidae) has emerged in the 1990’s as a serious citrus pest in southern Australia, NewZealand and parts of the Mediterranean Basin. The feeding of KCT on young and maturefruit causes scurfing (or halo) marking and rind bleaching, respectively. These blemishesreduce fruit quality, thereby reducing the packout of export quality fruit and rendering somefruit unsaleable. Information about KCT biology and ecology has been scarce, and inAustralia the management of KCT has been limited to the use of several insecticides. Havingestablished that KCT pupate in the soil below the citrus canopy, we initiated a search forboth arboreal and soil-dwelling natural enemies with the aim of developing an IPM systemfor KCT in Australian citrus orchards. The abundance of KCT in the canopy is inverselyrelated to the mortality of the soil-dwelling life-stages of KCT. The study has identified arange of soil dwelling mite species that are either demonstrated or likely predators of KCT.The diversity and abundance of these predators and the incidence of KCT in study orchardsis examined. The potential implications for the IPM of KCT are discussed.