Tuesday, December 11, 2007 - 3:47 PM
1076

Pseudophilothrips ichini, an approved biological control agent of Brazilian peppertree, Schinus terebinthifolius: Biology, host range, and impact studies

James P. Cuda, jcuda@ufl.edu1, Julio C. Medal, medal@ufl.edu1, Judy L. Gillmore, jlgi@ufl.edu1, and J. Henrique Pedrosa-Macedo, johpema@netpar.com.br2. (1) University of Florida, Department of Entomology & Nematology, Natural Area Drive, Bld. 970, Gainesville, FL, (2) Universidade de Federal do Parana, Engenharia Florestal, Rua Bom Jesus, 650, Curitiba, Parana, Brazil

Brazilian peppertree (BP), Schinus terebinthifolius Raddi, is an evergreen shrub or small tree native to Argentina, Paraguay and Brazil. This invasive plant, introduced into the US as a landscape ornamental in the 19th century, readily invades disturbed sites and natural communities. BP forms dense thickets that completely shade out and displace native vegetation, reducing the biodiversity of the native plant and animal communities. Direct contact with a toxic resin produced by the plant also can cause dermatitis. Exploratory surveys conducted in Brazil in the 1980s produced several promising insect natural enemies. One of the most damaging is the thrips Pseudophilothrips ichini (Hood). Feeding damage by the insect not only kills the meristems and causes flower abortion but also suppresses the growth of young plants (stem length by 40% and biomass by 46%) and curtails seed production in mature trees. Total development time (egg to adult) requires ca. 40 days, and up to four generations are produced annually. Host specificity studies conducted in Brazil and Florida using 46 plant species in 18 families indicated that P. ichini is capable of continuous reproduction only on BP and its congener S. molle L., an ornamental tree in California native to Peru that is becoming invasive in some areas. If released in Florida, P. ichini is unlikely to survive in the arid environment where S. molle thrives in California. In addition, field surveys in Brazil confirmed that under natural conditions where both Schinus species coexist, S. molle is not attacked by P. ichini.


Species 1: Thysanoptera Phlaeothripidae Pseudophilothrips ichini
Species 2: Sapindales Anacardiaceae Schinus terebinthifolius (Brazilian peppertree, Christmas berry)
Species 3: Sapindales Anacardiaceae Schinus molle (California peppertree, Peruvian peppertree)