Screening of Various Herbicide Modes of Action for Selective Control of Algae Responsible for Harmful Blooms

摘要

This research seeks to identify reduced risk chemical compounds that have selective activity against harmful algal blooms (HAB). The U.S. Army Corps of Engineers is responsible for managing numerous large reservoirs throughout the country, and the recent proliferation of HAB and the limited tools available for controlling these nuisance algae at a large scale have caused many Corps resource managers to seek non-conventional control methods. Numerous herbicides that target plant-specific enzyme sites, such as phytoene desaturase (PDS) and acetolactate synthase (ALS), are currently under consideration for registration and use in aquatic sites by the U.S. Environmental Protection Agency (USEPA). These compounds exhibit a wide margin of safety for fish and wildlife, and have proven to be highly selective herbicides against numerous aquatic macrophyte species. Because algae, including cyanobacteria, and higher plants have many of the same enzyme systems, some of the enzyme-inhibiting herbicides may be active against algal species responsible for harmful blooms. The U.S. Army Engineer Research and Development Center, Aquatic Nuisance Species Research Program (ANSRP) has encouraged research into innovative methods for managing HAB. While selective control of harmful algae remains an elusive goal, herbicides with modes of action that target the PDS and ALS enzyme systems are being screened to determine if these compounds have the potential to selectively control or inhibit the growth of bloom-forming algae.