TOMATO IS ONE OF THE MOST IMPORTANT VEGETABLES IN THE US, BUT PRODUCTION ACROSS THE COUNTRY IS INCREASINGLY THREATENED BY A THIRD RACE OF THE FUNGAL DISEASE, FUSARIUM WILT. PLANT RESISTANCE IS THE MOST EFFECTIVE MEANS OF DISEASE MANAGEMENT, AND VARIETIES BRED TO RESIST RACE 3 ARE AVAILABLE. HOWEVER, GROWERS HAVE BEEN SLOW TO ADOPT RACE 3 RESISTANT VARIETIES BECAUSE THESE ALL RELY ON A SINGLE GENE (I-3) FOR RESISTANCE, AND PRESENCE OF I-3 TYPICALLY RESULTS IN SMALLER FRUIT SIZE, WEAKER PLANTS, AND GREATER SENSITIVITY TO ANOTHER DISEASE, BACTERIAL SPOT. THIS PROJECT WILL COMBINE CONVENTIONAL BREEDING STRATEGIES WITH GENE EDITING TECHNIQUES TO DETERMINE THE CAUSE OF THESE NEGATIVE TRAITS AND TO ELIMINATE THEIR ASSOCIATION WITH THE I-3 GENE. BY THIS APPROACH, THE PERFORMANCE OF I-3-CONTAINING VARIETIES WILL BE IMPROVED AND THE UTILIZATION OF THIS GENE IN VARIETY DEVELOPMENT PROGRAMS WILL INCREASE, LEADING TO AN EXPANDED PORTFOLIO OF RACE 3 RESISTANT TOMATO VARIETIES, INCREASED GROWER ADOPTION, AND REDUCED CROP LOSSES DUE TO THIS DISEASE. ADDITIONALLY, NEW RACE 3 RESISTANCE GENES WILL BE IDENTIFIED FROM WILD TOMATO SPECIES, AND TRADITIONAL BREEDING METHODS WILL BE USED TO INCORPORATE THESE INTO IMPROVED TOMATO VARIETIES. THESE NEW GENES WILL BE COMBINED WITH I-3 AND WITH OTHER RACE 3 RESISTANCE GENES TO OBTAIN ENHANCED, LONG-LASTING RESISTANCE TO THIS DESTRUCTIVE DISEASE. ULTIMATELY, THESE EFFORTS WILL RESULT IN THE DEVELOPMENT OF IMPROVED FOL3 RESISTANT CULTIVARS, PROVIDING A MORE ECONOMICALLY SUSTAINABLE SOLUTION FOR TOMATO GROWERS THROUGHOUT THE US AND THE WORLD.