** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** THE FUNGUS FUSARIUM GRAMINEARUM CAUSES IMPORTANT DISEASES OF WHEAT, BARLEY, RICE, MAIZE, AND OTHER CEREAL CROPS. FUSARIUM HEAD BLIGHT (FHB) OF WHEAT AND OTHER SMALL GRAINS, AND GIBBERELLA EAR ROT (GER) OF MAIZE, ARE THE MOST COMMON AND DAMAGING OF THESE IN THE U.S. AND WORLDWIDE.EVEN MORE CONCERNING THAN DIRECT YIELD LOSS FROM REDUCED GRAIN WEIGHT IS CONTAMINATION OF INFECTED GRAINS WITH MYCOTOXINS, E.G. DEOXYNIVALENOL (DON), THAT ARE DANGEROUS FOR HUMAN AND ANIMAL HEALTH, AND SUBJECT TO REGULATION TO ENSURE COMPLIANCE WITH LOW TOLERANCE LIMITS.BOTH FHB AND GER HAVE A COMPLEX EPIDEMIOLOGY THAT INCLUDES MULTIPLE ALTERNATE HOSTS AND A VERY STRONG INFLUENCE OF THE ENVIRONMENT ON DISEASE OUTCOMES AND TOXIN ACCUMULATION. THE PATHOGEN POPULATION EXHIBITS A HIGH DEGREE OFVARIATION AMONG STRAINS, FURTHER CONTRIBUTING TO THE UNPREDICTABILITY OF DISEASE AND TOXIN LEVELS FROM YEAR TO YEAR.SINCE A SERIES OF MAJOR EPIDEMICS IN THE U.S. COST WHEAT GROWERS AROUND $3 BILLION DURING THE 1990S, FHB HAS RECEIVED INCREASED RESEARCH ATTENTION AND THIS HAS RESULTED IN THE DEVELOPMENT OF IMPROVED DISEASE FORECASTING MODELS, MORE EFFICACIOUS FUNGICIDES AND APPLICATION TECHNOLOGIES, AND NEW SOURCES OF RESISTANCE IN WHEAT AND BARLEY. IN CONTRAST, THERE ARE VERY FEW SIMILAR RESOURCES FOR GER, DESPITE TOTAL LOSSES IN THE U.S. THAT WERE 160 TIMES GREATER THAN THOSE DUE TO FHB IN 2020-2022. FURTHERMORE, INFESTED MAIZE STUBBLE LEFT IN THE FIELD AFTER HARVEST IS A PRIMARY SOURCE OF SPORES THAT CAUSE FHB, WHICH CONTINUES TO BE ONE OF THE MOST DAMAGING DISEASES OF WHEAT AND BARLEY IN THE U.S. WITH THE EXISTENCE OF A SINGLE PATHOGEN POPULATION CAUSING MOST GER AND FHB IN N. AMERICA, WE NEED TO FOCUS MUCH MORE ATTENTION ON MONITORING, MODELING, AND MANAGING FUSARIUM GRAMINEARUM ON MAIZE IN ORDER TO REDUCE LOSSES FROM BOTH OF THESE IMPORTANT DISEASES. THE PROPOSED RESEARCH WILL ADDRESS THIS CRITICAL NEED BY DEVELOPING NEW TOOLS AND RESOURCES TO STUDY, TRACK, AND MODEL FUSARIUM STRAINSCAUSING GER. OUR LONG-TERM GOAL IS TO IDENTIFY MARKERS THAT COULD BE USED TO DETECT AND DIAGNOSEPATHOGEN STRAINS THAT POSE A PARTICULARLY HIGH RISK(E.G., THAT HAVE HIGH LEVELS OF AGGRESSIVENESS ON WHEAT, CORN, OR BOTH;THAT HAVE INCREASED TOLERANCE TO ENVIRONMENTAL STRESS LIKE HEAT OR DROUGHT;OR THAT ARE MORE RESISTANT TO FUNGICIDES) SO THAT WE CAN EFFECTIVELY MONITORSHIFTS IN THE FUNGAL POPULATION IN THE FIELD. INCORPORATION OF THIS INFORMATION WITH DISEASE FORECASTING MODELS WILL HELP US TO BETTER MANAGE FHB AND GER DISEASE EPIDEMICS, BY PROVIDING BETTER SURVEILLANCE AND PREDICTION TOOLS FOR GROWERS.