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ARS Home » Research » Research Project #439642

Research Project: Integrated Management of South American Pests and Weeds

Location: Office of International Research Engagement and Cooperation

Project Number: 0210-22310-011-00-D
Project Type: In-House Appropriated

Start Date: Nov 8, 2020
End Date: Nov 7, 2025

Objective:
Objective 1: Conduct research on the systematics, biodiversity, and taxonomy of insects, pathogens and plants that are pests, or potential pests, of the Nation’s crops and natural ecosystems, as well as insects and microbes that are natural enemies of invasive pests. Especially those that show promise to be developed as biological control agents. Objective 2: Develop biological control programs for invasive plants threatening the US environments and agriculture, through the discovery, identification, efficacy testing, and safety testing of new biological control agents. This objective implies conducting faunistic and pathogen inventories to discover natural enemies that may serve as biological control agents for target species. It also involves studying the ecology and population dynamics of targeted weeds and their potential arthropod and pathogen biological control agents, and investigate the impact of weed suppression on community and ecosystem structure and function. Objective 3: Develop biological control programs for invasive arthropods threatening U.S. environments and agriculture, through the discovery, identification, efficacy testing, and safety testing of new biological control agents. Again, this involves conducting faunistic and pathogen inventories, as well as elucidating the biology, ecology and population dynamics of target insects and their potential arthropod and pathogen biological control agents. Objective 4: Conduct risk analyses to determine the environmental safety of new and existing potential biological controls, and investigate the impact of insect and plant suppression on community and ecosystem structure and function. This objective requires identifying the biological and physical parameters that affect the efficacy and safety of potential agents, including climatic conditions, host specificity, effective rearing conditions, and biogeography.

Approach:
Many of the invasive plants and arthropods in the United States are of South American origin, introduced without natural enemies from their native habitat. These organisms invade natural and agricultural communities, causing the disruption of ecosystem processes necessary for the sustenance of urban, agricultural, and natural areas. The research program at FuEDEI (ex-SABCL) aims at achieving long-term sustainable management of these invaders. Its Project Plan approved by OSQR in 2020 includes target weeds: the water fern (Salvinia molesta) commonly known as giant salvinia, Brazilian peppertree (Schinus terebinthifolius), Brazilian waterweed (Egeria densa), water primrose (Ludwigia hexapetala), water lettuce (Pistia stratiotes) and waterhyacinth (Pontederia crassipes ex-Eichhornia crassipes). Insect targets are cactus moth (Cactoblastis cactorum), little fire ant (Wasmannia auropunctata), Harrisia cactus mealybug (Hypogeococcus pungens), imported fire ants (Solenopsis invicta and S. richteri) and the Tawny crazy ant (Nylanderia fulva). The basic approach consists of the discovery, development, and release of natural enemies, and other biologically-based techniques such as semiochemicals. Research is required to determine the exact identity of both the invaders and their natural enemies, where to search for natural enemies of these invasive species, which of the various natural enemies are safe to import, and what effect such introductions could have on the invaded community. Long-term, sustainable, biological-control-based management of invasive species will result in the reduction of pesticide use, and provide landscape-level suppression of the targets. These research efforts will contribute to the recovery and rehabilitation of natural ecosystems and conservation of native species.