ARS Biocontrol Roadmap Comments_V2

Answers to each of the 5 questions below will be submitted at: https://arsbiocontrol.ars.usda.gov/

1. How can we improve this Roadmap that integrates biocontrol with other bio-based strategies and emerging tools?

The Roadmap presents a good first step toward the development and adoption of biocontrol and other bio-based strategies in agricultural production under a shared vision for sustainable pest, weed, and disease management. Its long-term impact, however, will depend on how effectively these concepts are translated into coordinated research, practical applications, and measurable outcomes for growers. The document could be improved by clearly articulating how biocontrol and other bio-based strategies could be integrated across different production systems or describing the barriers preventing its integration.

The Roadmap states that biocontrol is less expensive and more sustainable than traditional chemistry; however, this premise is not necessarily true nor supported by the evidence. The performance of biocontrol products is often more inconsistent than traditional chemistry. As such, appropriate grower expectations for bio-based control efficacy must be set.  We also have a long history of biological controls that have been unreliable. Some weed control programs have been delayed by ineffective biocontrol efforts. For example, the hydrelia fly was developed as a classic biocontrol for hydrilla and was released in Florida for diecious hydrilla control. Unfortunately, only about 10 percent suppression of diecious hydrilla was observed. It was also released for monoecious hydrilla control in North Carolina, but no individuals were ever found to persist on monoecious hydrilla. Another example is the use of the milfoil weevil in the control of Eurasian watermilfoil. While the weevil is effective at managing Eurasian watermilfoil when the insect is present at very high densities, it is rare for the required densities to occur in the environment.

While the Roadmap provides a broad overview of available technologies, it would benefit from a more defined framework showing how these tools interact—biologically, logistically, and economically—to achieve sustainable pest, weed, and disease control. Further, it is unclear how developed some of these technologies are. For example, while smart plant technology is introduced, there was little description of how developed this technology is or how quickly it could be implemented in production systems. Additionally, the Roadmap could strengthen its focus on adoption pathways and outcomes. Identifying specific barriers—such as regulatory constraints, production scalability, technology accessibility, storage stability and cost of implementation—and outlining approaches to address them would make the document more actionable.

Finally, although one of the stated purposes of the Roadmap is to “identify stakeholder needs related to biocontrol,” it does not address the specific challenges or priorities of growers. The Roadmap lacks a description of stakeholder needs or how they might be supported in this process, leaving a gap between the proposed research framework and the practical realities faced by growers. The Roadmap could be improved if key considerations such as product reliability, economic feasibility, regulatory barriers, and on-farm implementation. Without these perspectives, the Roadmap risks overlooking the practical conditions necessary for widespread adoption and long-term success.

• Are your industry needs and the associated research goals, strategies, and tools reflected in the Roadmap, and if not, what science and tools are missing?

From a weed science perspective, the Roadmap only partially reflects current discipline and industry needs. While it outlines a range of biological, bio-based and emerging tools, it lacks detail on how these can be effectively applied to the unique challenges of weed control. The most significant omission is the lack of discussion on herbicide-resistant weeds, a major issue in agricultural production. The Roadmap would be strengthened by explicitly linking biocontrol research to resistance mitigation and how biocontrol can be integrated into integrated weed management approaches on farm. For example, biotechnological tools, such as gene drives, could be explored to reduce the spread of herbicide resistance genes in specific weed populations or to suppress and reduce the size of resistant populations before they become dominant.

Another example pertains to research being conducted by an Israeli-based group named WeedOut, in collaboration with the University of California, Davis. They have explored and begun the EPA registration process for a sterile pollen technique (SPT) to manage Palmer amaranth populations. This method involves applying X-ray irradiated pollen from male plants to female plants, which results in sterile weed seeds and a reduction in the weed seed bank.

In addition, the document could better address the practical aspects of adoption for weed-focused biocontrol tools. This includes improving formulation stability, delivery systems, and field persistence of bio-based weed control products under field-based environmental variability. Greater emphasis on decision-support tools and precision technologies (i.e. AI-driven weed identification and targeted application systems) would also align with grower needs. Regulatory uncertainty surrounding the approval and use of bioherbicides and genetically engineered biocontrol agents also remains a significant barrier that must be considered early in research planning. This coupled with inconsistent or limited funding for long-term biocontrol research could hinder progress especially considering that all listed multistate biocontrol research projects referenced in the Roadmap are inactive or terminating.

• Please indicate your top problems or industry needs that could be solved by biocontrol or bio-based tools, and suggest the tools that would help solve your problems.

• Formulation chemistry. The formulation chemistry of biocontrol agents is crucial, as many of these agents cannot be sprayed with conventional pesticides due to stability or compatibility issues. This forces farmers to make another trip across the field thus using more time and fuel. These hurdles must be overcome before we can even consider integrating them into tank mixes or applications. The USDA should invite formulation chemists to the discussion to see if there are cost effective ways to allow these products to be co-applied with conventional pesticides.

• The spread of herbicide-resistant weeds and lack of effective bioherbicide options. Bioherbicides derived from microbial metabolites or plant secondary compounds could aid in the development of new modes of action and help manage resistant populations. Additionally, gene-editing tools and gene drives could eventually be explored to slow or disrupt the spread of resistance traits in problematic species.

• Better, faster identification of what part of the field to treat. Many of these biocontrol products are more expensive than conventional pesticides. Research into supporting technologies could find more efficient ways to identify which portions of a field need treatment and help mitigate these costs. For example, AI-based weed detection systems, precision sprayers, and drone-based mapping could optimize bio-based applications to specific species and growth stages thus improving efficiency and cost-effectiveness. Expanded research funding and regulatory clarity are essential to advance these innovations from the lab to the field.

• Who are the potential collaborators in biocontrol and bio-based tools that would address your industry’s top problems.

Potential collaborators include USDA-ARS and university weed science programs with expertise in weed science, biological control, plant–microbe interactions, and resistance management. This would include collaborators from the WSSA,  Entomological Society of America (ESA), American Phytopathological Society (APS), and the American Society of Agronomy, Crop Science Society of America and the Soil Science Society of America (ASA-CSSA-SSSA), as well as the American Farm Bureau Federation (AFBF), National Farmers Union (NFU), National Alliance of Independent Crop Consultants (NAICC).

Partnerships with biotechnology companies developing microbial or RNA-based bioherbicides and exploring gene-editing or gene-drive applications for weed suppression would aid in the development of these tools. Collaboration with engineering and data science teams developing precision application technologies could further bridge the gap between lab-based research and field implementation.

In addition, strong engagement with extension specialists, grower organizations (corn, cotton, soybeans, wheat, specialty crops/fruits and vegetables) and other federal agencies such as EPA, Department of the Interior, USDA IR-4 Program and Forest Service, USFWS, and NMFS, will be essential for developing practical, compliant, and scalable solutions.

Industry partnership is likely a key to the success of this endeavor. Collaborators could include biocontrol product developers, agrichemical manufacturers and distributors such as Bayer, BASF, Corteva, Syngenta, Winfield United, Valent Bioscience’s, Harpe Bioherbicides, Rosens, DPH Biologicals, or similar industry organizations like CropLife America (CLA) and Chemical Producers and Distributors of Agrotechnology (CPDA). Most agrichemical manufacturers have biological based product offerings, as do most of the major agrichemical distributors. Many of the recommendations made to farmers at the retail level are the result of messaging from the distribution network. Effectively deploying any new technology will depend in part on involving this part of the agricultural supply chain. This kind of collaboration can bring diverse insights.

• Who should we invite from your organization or industry to a workshop on biocontrol and bio-based tools? Would you prefer in-person, hybrid, or virtual workshops?

Representatives from university-based weed science programs, USDA-ARS weed and invasive plant research units, and extension specialists actively engaged in integrated weed management should be invited. It would also be valuable to include regulatory scientists familiar with bioherbicide approval processes and funding program officers to discuss support for biocontrol research. Below are a few examples of weed scientists, and regulatory and industry specialists with relevant expertise and interest:

• Dr. John Wallace, Penn State: expertise in cover crops for integrated weed management.
• Dr. Steve Duke, USDA ARS Retired: an internationally recognized expert on weed management and biopesticides
• Dr. Marcelo Moretti, Oregon St, WSSA Biocontrol Section Chair, 2025
• Megan Schill and Muthukumar Bagavathiannan. Texas A&M, Exploring Weed Suppression Abilities in Sorghum bicolor with High Sorgoleone Production.
• Debra Smitherman Scott McElroy. Auburn University; Utilizing Cover Crops as a Weed Management Tool for Combatting Amaranthus spp. Resistance.
• T. Casey Barickman, Charles Cantrell, Amber Reichley. USDA-Natural Products Utilization Research Unit, MS; A Water Soluble β-Triketone Enriched Extract of Manuka Oil: Increased Weed Control Efficacy Compared to Two Organic Non-Selective Herbicides.
• Ping Gong and Seung Ho Chung. US Army Engineer Research and Development Center, Vicksburg, MS; Rapid and Accurate Characterization of Target Genes for Genetic Biocontrol of Invasive Aquatic Plant Species.
• Dr. Bill Chism (experience from the federal regulatory side)
• Linda Hollis, EPA OPP Brach Chief for Biochemical Pesticide Branch
• Shannon Borges, EPA OPP, Acting Director for the Biopesticides, and Pollution Prevention Division (BPPD)
• Dr. Lynn Sosnokie, Cornell; expertise in novel weed management technologies and specialty crop production
• Dr. Kevin Bradley, Univ. of Missouri; experience evaluating several forms of integrated weed management such as electrocution, harvest weed seed control, cover crops, etc., understands what is practical at scale.
• Dr. Chandrashekar Aradhya; Head of Herbicide Resistance Management at Bayer
• Michael Duff, Vice President of Biostimulants, Research and Product Development at Rosen’s Inc.; Much of his work has focused on developing biological formulations that are compatible with other pesticides and fertilizers.

Given the need for broad participation across regions and institutions, a hybrid workshop format might be ideal. It would allow in-person collaboration among researchers and policymakers while enabling remote participation from industry scientists, growers, and extension personnel who may have limited travel budgets or field responsibilities. A virtual workshop may better ensure equal access and input from participants though.

More info is at: https://arsbiocontrol.ars.usda.gov/