Document Type : Original Article
Central Agricultural Laboratory of Pesticides, Agricultural Research Center,Sabahia, Alexandria
White mango scale, Aulacaspis tubercularis Newstead (Hemiptera: Diaspididae) is a serious pest on mango (Mangifera spp.), (Sapindales: Anacardiaceae) which became recently a troublesome pest in all mango orchards in Egypt. It causes fatal damage especially to late cultivars by sucking leaves which turn pale-green or yellow and ultimately die or fruit causing conspicuous pink blemishes around insect feeding sites resulting in external lesions rendering it unmarketable for export. Seasonal abundance was estimated throughout 2 successive years (2008 and 2009) and showed that the white mango scale (A. tubercularis) had four peaks for its population density during the two studied years, (April, August, October and December, 2008) and (March, July, September and December, 2009). Study of weather factors, [daily mean temperature (oC), relative humidity (%), dew point (oC) and wind speed (Km/h)] effects on A.tubercularis population density illustrated that there was significant positive relationship between (daily mean temperature and relative humidity) and counted population density, but there was a significant negative relationship between (wind speed and dew point) and counted population density. Two successive field experiments for eight weeks during early spring (2009 – 2010) aimed to test some summer/light mineral oils, (super masrona®, CAPL2® and Diver®) against A. tubercularis on mango trees. The tested mineral oils were effective by the following descending order : Diver > CAPL2® > super masrona® without significant differences between diver and CAPL2 and significant differences with super masrona, with the same effective trend and same statistical means, during the two seasonal experiments. The study recorded a little numbers of natural enemies (Parasitoids (Aphytis mytilaspidis (Le Baron)andEncarsia citrina (Craw) (Hymenoptera: Aphelinidae)), and predators (Chilocorus bipustulatus (L.) andScymnus syriacus Marseul (Coleoptera: Coccinellidae)). It may be killed by previous bad history of chemical insecticides usage in this area.