Effectiveness of the predatory beetle, Cybocephalus binotatus, in controlling mango scale populations in commercial orchards.
Lagadec M. D. le
Author Affiliation: Merensky Technological Services, P.O. Box 14, Duivelskloof 0835, South Africa.
: 141-146
Abstract : Cybocephalus binotatus, a predatory beetle of mango scale insects (Aulacaspis tubercularis) was introduced into the South African mango growing areas in 1995 and has since become well established. The effectiveness of this predator in controlling mango scales was investigated during the 1999/2000 mango season. A retrospective study correlating scale populations in mango orchards to Cybocephalus releases showed that Cybocephalus effectively reduced scale populations approximately two weeks after their release. Laboratory studies, trials carried out in insect-proof tents and large field trials revealed that the C. binotatus successfully controls scale populations to levels of 2-3% scale infestation and that the female predatory beetles produce only as many offspring as the scale population can support. The beetles are mass feeders and require a substantial scale population to sustain them. It was found that the rate of scale population decline was somewhat independent of the number of predatory beetles released and remained reasonably constant. For effective scale control, it is recommended that between 500 and 1000 beetles be released per hectare of cultivated mangoes. The study concluded that by combining the effects of predatory beetles and parasitic wasps the mango scale insects can be successfully controlled biologically.