Philip Berger is an internationally known plant pathologist who has made significant contributions to both academia and regulatory science. A native of New Mexico, Berger received BA and MS degrees from the University of Minnesota in 1977 and 1980, respectively. He received a PhD in plant pathology in 1983 from Texas A&M University, and he served as a post-doctoral scientist at the University of Kentucky before joining the faculty of the University of Idaho in 1988. His research program spanned many areas of plant virology, including diagnostics, etiology, epidemiology, evolution, molecular biology, and biotechnological approaches toward virus disease diagnosis and control. At Idaho, he advanced through the professorial ranks and served as chair of the Plant Pathology Division and associate director of the Idaho Experiment Station.
In 2003, Berger joined the USDA Animal Plant Health Inspection Service (APHIS) in Raleigh, North Carolina, as the national science program leader for molecular diagnostics and biotechnology at the Plant Protection and Quarantine (PPQ) Center for Plant Health Science and Technology. In 2008, he became executive director for PPQ Science and Technology (S&T), overseeing seven national laboratories that support regulatory research for plant pest exclusion, detection, identification, management, and risk analysis. Berger played a key role in implementing or supporting nation-wide initiatives affecting PPQ's mission to safeguard U.S. agriculture and enhance safe trade.
An example of Berger's key contributions to PPQ was his leadership in advancing state-of-the-art and high-quality diagnostic technologies for regulatory decision making. Beginning with assays used to diagnose the select agent pathogen Ralstonia solanacearum R3B2, he supported robust and extensive clinical-level validations of crucial diagnostic methods used for regulatory purposes. The use of these methods helped the agency prevent spread of this pathogen after it was introduced into the United States in 2002 and prevented regulatory action in response to other incidents involving nonquarantine strains of R. solanacearum. Berger advanced capacity building in PPQ diagnostics to meet and maintain international quality management standards. In 2015, the PPQ Beltsville Laboratory became the first regulatory plant diagnostic laboratory in the United States to obtain ISO 17025 accreditation, resulting in international recognition of the high standards of PPQ diagnostic methods. Berger championed the adaptation of new technologies for regulatory diagnostics and led development of PPQ capacity for high-throughput sequencing and the development and validation of CANARY, a rapid pest detection technique that can be applied at ports of entry.
Berger founded and led the development of PPQ's National Plant Protection Laboratory Accreditation Program (NPPLAP), which accredits state and university partner labs to perform regulatory diagnostics. Through this program, PPQ was able to greatly expand national diagnostic capacity and effectively leverage the distributed system and capacity of the National Plant Diagnostic Network (NPDN) to aid in emergency responses to confine plant pathogens. The formation of complementary state–federal partnership networks has been critical in the response to serious outbreaks of diseases, such as sudden oak death (SOD), plum pox virus, and Huanglongbing (citrus greening) and has provided access to rapid, accurate, and effective diagnostic lab services in emergency and ongoing pest programs. Working with the NPDN, NPPLAP also helped establish a strong quality-management system to support U.S. plant disease diagnostics. Berger's support for plant health laboratory networks resulted in recognition of his leadership by the 2016 USDA Abraham Lincoln Honor Awards—the most prestigious departmental awards presented by the Secretary of Agriculture—in the category of “Increasing Global Food Security."
Berger has also played key roles in supporting PPQ regulatory programs, policies, and actions. For example, Berger has provided leadership in the USDA response to Huanglongbing disease, which now affects citrus in nearly every part of the United States where citrus is grown. He has provided scientific management of the Huanglongbing Multi-Agency Coordination Group portfolio to provide near-term solutions for citrus growers affected by this disease. He also advanced novel technologies to address this disease, including the development of risk-based predictive models, improved diagnostics, biological control programs, and detection of diseased trees using canines.
Berger has led the APHIS technical and scientific responses to numerous other introductions of exotic plant pathogens, including Phytophthora ramorum, plum pox virus, potato cyst nematode in Idaho, and gladiolus rust in Florida. Those responses have been effective: The risk posed by spread of P. ramorum in nursery stock has been reduced; potato cyst nematode has been contained and the risk to U.S. potato production has been reduced; plum pox virus has been eradicated in Pennsylvania; and gladiolus rust has been deregulated. When sweet orange scab and citrus black spot were detected in the United States, Berger led the validation of emergency-use diagnostic protocols for these pathogens, providing critical methods for survey and regulatory activities. To mitigate the impacts on growers affected by quarantines, he led the development of risk assessments that showed that fresh fruit is not a pathway for disease spread if the fruit undergoes certain packinghouse procedures. This information was used to update regulatory requirements and provided conditions to allow interstate movement of citrus outside quarantine areas.
As executive director for PPQ S&T, Berger also led PPQ's technical analyses for obtaining and maintaining U.S. import and export markets. Specifically, he enhanced the organization's capacity to analyze the risks associated with all requests to import agricultural commodities into the United States and to provide critical support to U.S. industries seeking access to foreign markets. These risk analyses inform the management work plans that allow commodities to safely enter the country. Without this critical work, markets for numerous U.S. exports also would be affected, and access to the U.S. market for many commodities would be curtailed or prohibited. Berger's leadership in the technical and analytical support for recent U.S. disease outbreaks—including flag smut of wheat in 2015 and bacterial leaf streak of corn in 2016—has protected growers from potential impacts on grain export markets.
Berger has been an active member of The American Phytopathological Society since 1977. He has served on numerous committees, including as chair of the Virology Committee. He also served as an associate editor of Phytopathology and has reviewed many manuscripts for Phytopathology and Plant Disease, as well as other virology journals. Berger has authored more than 90 refereed research papers, books, and book chapters.
