Steps Toward Managing The Exotic Armored Scale Andaspis Punicae In Litchi In Florida And Puerto Rico

The exotic scale, Andaspis punicae (Homoptera: Diaspididae), was detected in 1993 in Florida invading litchi groves. It caused dieback of branches, reduced tree vigor and eventually killed the trees. During 2004 this scale was detected in Puerto Rico affecting litchis. The scale has also been associated with symptoms known as 'corky bark' in Florida. Here we present preliminary results of studies on scale biology, chemical control, efforts toward biological control with parasitoids and preliminary results of the possible association between the scale and the causal agent of 'corky bark'. On-going studies on scale biology demonstrated that the life cycle of the scales is longer than 40 days. Surveys in Florida and Guam showed that the scale was found in Litchi chinensis, Euphoria longan, Mangifera indica, Annona cherimola χ A. squamosa and Rambutan, Nephelium lappaceum. In Florida, levels of parasitism by the native parasitoid Encarsia lounsburyi (Hymenoptera: Aphelinidae) ranged between 2.9 and 26.1 percent. E. lounsburyi was also found parasitizing the scale species in Puerto Rico. Parasitism in Guam was caused by Encarsia inquirenda. The chemicals, KnackR (Pyriproxyfen), ApplaudR (buprofezin), imidacloprid and NovaluronR (benzoylurea) provided significant scale control 50 days after their application, but their use is restricted by application costs. Effect of a fungicide and an insecticide on scale development and symptoms of corky bark were studied during 2004.