Grafton-Cardwell, E.E. 2000 Citrus: integrating biological control and insecticide treatments for cottony cushion scale and other scale pests.. California Conference on Biological Control II, The Historic Mission Inn Riverside, California, USA, 11-12 July, 2000. Center for Biological Control, College of Natural Resources, University of California Berkeley
Notes: The insect growth regulators pyriproxifen and buprofezin are rapidly gaining registration in many crops for controlling various pests, especially Homopteran insects. In citrus, they exert excellent control of California red scale, Aonidiella aurantii. While the Environmental Protection Agency considers these to be "reduced risk" pesticides because of their low mammalian toxicity, these insecticides sometimes have severe consequences for integrated pest management programmes. Citrus relies heavily on vedalia beetle, Rodolia cardinalis, for control of cottony cushion scale, Icerya purchasi, and the insect growth regulators are highly toxic to predatory beetles. In our study, pyriproxifen was toxic for a longer period of time a greater number of life stages compared to buprofezin. Severe outbreaks of cottony cushion scale followed widespread use of pyriproxifen in 1998. When pyriproxifen use diminished in 1999, outbreaks occurred over a smaller area. These insecticides can potentially be used for citrus IPM if not sprayed during the period that vedalia beetle is most active, February-June. However, growers may be at the mercy of these insecticides gaining registration and extensive use in neighboring crops.