MAIZE IS A SOCIALLY AND ECONOMICALLY IMPORTANT CROP, HOWEVER, ITS PRODUCTION IS SEVERELY HINDERED BY DISEASES THAT ARE CAUSED BY VARIOUS BACTERIAL, FUNGAL, AND VIRAL PATHOGENS. THERE ARE NUMEROUS APPROACHES TO REDUCE THE NEGATIVE EFFECTS OF DISEASE ON MAIZE PRODUCTION BUT BREEDING FOR IMPROVED RESISTANCE STANDS OUT AS A SUSTAINABLE AND EFFECTIVE METHOD. DESPITE ITS PROMISE, BREEDING FOR DISEASE RESISTANCE IN MAIZE IS CHALLENGING, AS RESISTANCE IS CONDITIONED BY MANY SMALL EFFECT GENES. IDENTIFYING THESE SMALL EFFECT GENES IS DIFFICULT AND COMBINING IDENTIFIED RESISTANCE GENES INTO A SINGLE VARIETY IS LABORIOUS. THIS PROJECT AIMS TO BETTER IDENTIFY RESISTANCE GENES IN MAIZE LINES THAT ARE MORE AMENABLE TO USE IN AN APPLIED BREEDING PROGRAM.THIS PROJECT FOCUSES ON A SINGLE DISEASE, FUSARIUM SEEDLING ROT, WHICH IS CAUSED BY THE FUNGAL PATHOGEN FUSARIUM VERTICILLIOIDES. FUSARIUM SEEDLING ROT OCCURS AT EARLY STAGES IN MAIZE'S DEVELOPMENT BEFORE IT HAS HAD THE OPPORTUNITY TO FORM EFFECTIVE PHYSICAL BARRIERS TO FUNGAL INFECTION AND COLONIZATION. THIS MEANS THAT MAIZE'S RESISTANCE TO THIS DISEASE IS MORE DEPENDENT ON ANTI-FUNGAL BIOCHEMICALS THAT ARE PRODUCED IN RESPONSE TO INFECTION. ONE TYPE OF BIOCHEMICALS THAT HAVE BEEN SHOWN TO BE IMPORTANT IN FUSARIUM SEEDLING ROT RESISTANCE ARE TERPENOID PHYTOALEXINS. ACCURATE DETECTION AND QUANTIFICATION OF THESE PHYTOALEXINS WAS NOT POSSIBLE UNTIL THE PAST DECADE.THIS PROJECT WILL USE DIFFERENT MAIZE LINES THAT VARY IN THE QUANTITY AND QUALITY OF PHYTOALEXIN GENES AND PHYTOALEXIN PRODUCTION. BY MEASURING HOW THESE LINES RESPOND TO F. VERTICILLIOIDES INFECTION WE WILL BE ABLE TO IDENTIFY THE GENES AND PHYTOALEXINS THAT PROMOTE FUSARIUM SEEDLING ROT RESISTANCE. THIS PROJECT WILL OFFER GENETIC AND BIOCHEMICAL INSIGHTS ON MAIZE RESISTANCE TO A KEY DISEASE, WHICH CAN IN TURN BE UTILIZED BY PLANT BREEDERS TO IMPROVE MAIZE PRODUCTION IN A SUSTAINABLE FASHION.