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ARS Home » Southeast Area » Fort Lauderdale, Florida » Invasive Plant Research Laboratory » Research » Research Project #442561

Research Project: FDACS Assistance in Release, Establishment, and Evaluation of the Brazilian Pepper Biological Control Agents

Location: Invasive Plant Research Laboratory

Project Number: 6032-22000-013-098-A
Project Type: Cooperative Agreement

Start Date: Jun 1, 2022
End Date: Apr 30, 2023

1. Maintain laboratory colonies of the Brazilian pepper biological control agents. 2. Mass produce and release the Brazilian pepper biological control agents. 3. Confirm safety of the Brazilian pepper biological control agents.

Brazilian peppertree is one of the worst environmental and agricultural weeds worldwide. In the USA, this weed is one of the most aggressive and widespread invasive species in California, Florida, Hawaii, and Texas. Brazilian peppertree is a threat to diverse natural areas, agriculture, and cattle production. This weed has colonized most of the Florida peninsula, covering more than 280,000 ha, often with dense monospecific stands that eliminate native plant growth. Brazilian peppertree is a woody shrub that often grows in dense thickets in the invaded range. The male flowers produce abundant pollen that is exploited by native and introduced pollinators but is a source of nasal congestion, rhinitis, and other conditions in sensitive humans. The fruit are also toxic when consumed by birds and their volatiles can cause numerous respiratory and skin reactions in sensitive humans. The goals of this study are to document thrips mass production, release, and local persistence on Brazilian peppertree throughout the invaded range in Florida. While conducting these studies we also evaluated the effect of the number of agents released and time interval since release on thrips persistence. The overall goal is to reduce the competitive nature of the invasive weed using sustainable and cost-effective methods that reduce dependence on synthetic herbicides. The outline for how this issue will be approached is as follows: 1. Establishment of field populations of newly approved agents by mass production of laboratory colonies and release onto groomed field plants. 2. Improve mass production with examination of optimal plant fertilizer levels. 3. Measure impact of biological control on the weed by measuring plant demographic parameters. 4. Confirm quarantine host range testing by exposing vulnerable plants integrated in a garden of the host weed.