Location: Invasive Plant Research Laboratory
2012 Annual Report
The health and functioning of the greater Everglades ecosystem is being compromised by the proliferation of invasive exotic species. Brazilian peppertree (Schinus terebinthifolius Anacardiaceae) is acknowledged to be one of the most harmful invasive plant species decreasing biodiversity and proper functioning of the system. The plant presently covers over 280,000 ha in southern Florida alone. No-choice tests of Florida relatives of the weed in the same family were conducted with a prospective agent the thrips Pseudophilothrips ichini to determine risk to the most vulnerable species. Of the 13 species tested, a small number of larvae completed development on Pistacia vera, Metopium toxiferum and Schinus molle (all hosts from no-choice tests). Thrips choice tests were conducted between the weed and these three species. These results indicate that when the adults are given a choice they almost always chose to feed and lay eggs on the weed; a single thrips was found on Metopium in one of the choice tests. Multiple generation tests were initiated and suggest (though still underway) that the thrips will not be able to sustain a population only on these non-target species. Finally, research was initiated to determine if a different thrips population from a more tropical climate had different host specificity. However, results indicate that they constitute a similar threat to Metopium toxiferum, Pistacia vera, and Rhus typhina.