PLANT REPRODUCTION IS HIGHLY SENSITIVE TO CHANGING ENVIRONMENTAL CONDITIONS, WITH DEVIATIONS FROM OPTIMAL TEMPERATURE HAVING PROFOUND NEGATIVE EFFECTS ON MULTIPLE ASPECTS OF REPRODUCTION. PLANTS REPRODUCE THROUGH A PRECISE DEVELOPMENTAL PROCESS WHICH YIELDS FRUITS AND SEEDS THAT ARE THE CENTRAL PRODUCTS OF AGRICULTURE. SHORT- AND LONG-TERM INCREASES IN TEMPERATURE DURING PLANT REPRODUCTION PREVENT SUCCESSFUL FERTILIZATION, RESULTING IN IMPAIRED SEED AND FRUIT PRODUCTION THAT CAN LEAD TO DEVASTATING CROP LOSSES. IN PARTICULAR, THE DEVELOPMENT, GERMINATION, AND TUBE GROWTH OF POLLEN ARE ESSENTIAL FOR PLANT FERTILIZATION, BUT ALL OF THESE PROCESSES ARE EXTREMELY SENSITIVE TO HIGH TEMPERATURE STRESS. OUR TEAM HAS EXAMINED THE DETRIMENTAL EFFECTS OF ELEVATED TEMPERATURE ON REPRODUCTIVE SUCCESS OF TOMATO, AN IMPORTANT AGRICULTURAL SPECIES, AND HAVE BEGUN TO UNCOVER SIGNALS INDUCED BY HIGH TEMPERATURE THAT LEAD TO NEGATIVE IMPACTS ON POLLEN FUNCTION. WE HAVE FOUND THAT TOMATO POLLEN TUBES TRANSIENTLY EXPOSED TO ELEVATED TEMPERATURE HAVE INCREASED LEVELS OF REACTIVE OXYGEN SPECIES, A GROUP OF REACTIVE CHEMICALS THAT CAN DAMAGE CELLULAR MOLECULES. WE HAVE ALSO UNCOVERED A ROLE FOR FLAVONOLS - ANTIOXIDANT COMPOUNDS PRODUCED BY PLANTS - IN PROTECTING POLLEN FROM HIGH TEMPERATURE STRESS. THE GOAL OF THIS PROJECT IS TO BETTER UNDERSTAND HOW ELEVATED TEMPERATURE INCREASES REACTIVE OXYGEN SPECIES IN POLLEN AND HOW PLANTS CAN PROTECT THEMSELVES FROM THESE REACTIVE AND DAMAGING MOLECULES BY SYNTHESIS OF ANTIOXIDANTS. A GOAL IS TO APPLY THIS KNOWLEDGE TO BREEDING OR GENE EDITING TO YIELD TOMATO PLANTS BETTER ADAPTED TO INCREASES IN TEMPERATURE LINKED TO GLOBAL CLIMATE CHANGE.?