As the National Seed Health System (NSHS) approaches its 25th anniversary in 2026, its mission remains as vital as ever: ensuring that seeds moving across international borders are healthy, tested, and trusted. Administered by Iowa State University’s Seed Science Center under authorization of USDA-APHIS, the NSHS has spent a quarter century protecting the integrity of U.S. seed exports and supporting the global agricultural supply chain.
“Healthy seeds are the foundation of healthy plants, resilient food systems, and sustainable trade,” said Dr. Scott Heuchelin, NSHS Director. “For a quarter century, the NSHS has worked to protect that foundation by ensuring that seed shipped across borders is safe, tested, and trustworthy.”
From Five to Thirty: Growth Rooted in Collaboration
When the NSHS was formally established in 2001, just five entities were accredited under the program. Today, that number has grown to 30—evidence of its credibility and continued relevance in a rapidly changing industry.
“Three of the five original accredited entities are still accredited today,” said Kelly Iverson, NSHS Administrator. “That kind of longevity speaks to the value and trust our partners place in the system.”
Iverson also reflected on two defining milestones in the program’s history.
“The creation of the NSHS itself was a major accomplishment,” she explained. “To be accepted nationally, it had to be passed into the federal rules and regulations. That happened in 1999 with the final rule, 7 CFR Part 353, thanks to the hard work of a dedicated group from industry, USDA APHIS PPQ, Iowa State University, State Departments of Agriculture, and others.”
A second milestone came in 2020, when the Administration Unit at the Seed Science Center was able to hire a full-time position dedicated to supporting daily program operations. “Prior to that,” Iverson said, “the NSHS was staffed through the part-time efforts of several employees. Having a full-time administrator has really strengthened our ability to serve accredited entities and respond to emerging needs.”
Global Partnerships for a Safer Seed System
The NSHS plays a critical role in fostering international trust and trade by promoting harmonization of seed health testing standards.
“Part of NSHS’s mission is to work on global harmonization to promote international phytosanitary reform and foster fair, equitable trade,” Iverson said. “This year, we became a member of ISHI, the International Seed Health Initiative, to collaborate on method validations. We’re also partnering with ISTA, the International Seed Trade Association, to develop an assay that meets the requirements of both organizations.”
Such partnerships help ensure U.S. seed companies maintain a strong reputation as reliable suppliers in global markets; a reputation backed by rigorous science and consistent testing protocols.
Science Driving the Future
When NSHS began, seed health testing relied on traditional methods such as selective media plating, freeze blotters, and grow-outs—procedures that could take many days to complete. Today, advances in molecular diagnostics are accelerating results. “There has been a shift toward qPCR assays, which provide faster and more precise detection,” Iverson noted.
Today, as global trade accelerates and climate change shifts pest and pathogen pressures, this work is more vital than ever.
“New challenges continue to emerge, from introduced or evolving diseases to the need for harmonized international testing standards,” Heuchelin said. “In partnership with USDA-APHIS, industry experts, and seed health specialists worldwide, NSHS continues to advance detection methods and enhance reliability to prevent the spread of seedborne pathogens.”
Currently, NSHS scientist Jeffrey Williams is developing a seed extract qPCR method for maize to detect Goss’s Wilt, in collaboration with industry partners—an example of how NSHS science remains at the forefront of protecting seed health.
Building on a Legacy of Trust
Over the past 25 years, NSHS has safeguarded billions of dollars in U.S. seed exports and built international confidence in American agriculture. Its publicly available testing methods, accessible through seedhealth.org, ensure consistency and transparency for laboratories and regulators worldwide.
“Looking forward,” said Dr. Heuchelin, “NSHS will continue to strengthen collaboration with researchers, industry, and regulatory partners to meet the challenges of a changing agricultural landscape. We are committed to integrating new technologies, enhancing diagnostic accuracy, promoting international phytosanitary harmonization, and fostering fair trade.”
As the program celebrates its 25th anniversary, both Heuchelin and Iverson agree that its success lies in a simple truth: healthy seeds are the first step toward global food security and the NSHS is ensuring that first step remains strong, science-based, and globally trusted.