Wakgari, W.M. 2001 The current status of the biocontrol of Ceroplastes destructor Newstead (Hemiptera : Coccidae) on Citrus and Syzygium in South Africa.. Biocontrol Science and Technology 11(3): 339-352.

Notes: The incidence of parasitism and predation of the third instar and adult Ceroplastes destructor Newstead (Hemiptera: Coccidae) on Citrus reticulata (Blanco) and Syzygium (=Eugenia) malaccensis (L.) in the Western Cape, South Africa, was assessed from June 1997 to December 1999. Seven primary and three secondary parasitoids, as well as four predator species were identified. Aprostocetus (=Tetrastichus) ceroplastae (Girault) was the predominant parasitoid species accounting for 78.9% of the total primary parasitoids. Peak numbers of parasitoids and predators were synchronized with peak emergence of the scale stages susceptible to parasitism and predation, indicating that the scale-parasitoid/predator association contained a density-dependent regulatory mechanism. Parasitoids demonstrated density-dependence at the third instar and pre-ovipositing female stage for scales on C. reticulata and S. malaccensis, respectively whereas predators acted as a density-dependent mortality factor only during the pre-ovipositing female stage of scales C. reticulata. However; the density-dependent process of parasitism and predation fluctuated between generations, indicating that the regulatory effects of these mortality agents may not be strong enough to provide long-term suppression of scales under the current citricultural practices. Mortality due to disease was either inversely related or not related to scale density. Body-length of A. ceroplastae varied significantly between sampling periods, parasitoid sex and scale stage from which it was reared (P <0.001). The sex ratio of A. ceroplastae reared from early third instar C. destructor was male biased while that of parasitoids reared from mature adult female was slightly female biased.