THIS PROJECT SEEKS TO DISCOVER METHODS TO ALLOW CREATION OF MAIZE LINES THAT PRODUCE GRAIN WITH 1) OPTIMIZED NUTRITIONAL QUALITY FOR HUMANS AND ANIMALS AND 2) HIGH AGRONOMIC AND PROCESSING QUALITY IMPARTED BY HARD KERNEL TEXTURE. MAIZE GRAIN OFFERS THE ADVANTAGES OF EXTREMELY HIGH YIELDS AND ADAPTABILITY TO VARIOUS CLIMATES AND GEOGRAPHIC LOCATIONS, BUT SUFFERS FROM SUB-OPTIMAL NUTRITIONAL QUALITY IN TERMS OF AMINO ACID BALANCE. A LONG-STANDING BODY OF RESEARCH HAS SUCCEEDED TO IMPROVE AMINO ACID CONTENT SO THAT MAIZE GRAIN POTENTIALLY CAN BE A BETTER FOOD SOURCE. HOWEVER, THE CHANGES ACHIEVED SO FAR ARE INEXTRICABLY LINKED TO A DELETERIOUS ALTERATION IN KERNEL QUALITY. SPECIFICALLY, WHEN NUTRITIONAL QUALITY IS IMPROVED, THE HARD OUTER LAYER OF THE KERNEL THAT IMPARTS GOOD QUALITIES FOR GRAIN STORAGE, PROCESSING, FOOD APPLICATION, AND RESISTANCE TO DISEASE IS LOST. THIS RESEARCH WILL TEST SEVERAL NOVEL METHODS OF ADDING GENETIC CHANGES TO THE NUTRITIONALLY IMPROVED LINES THAT WILL RESTORE KERNEL HARDNESS WHILE KEEPING THE NUTRITIONAL ADVANTAGES AND AVOIDING YIELD DECREASES. TO IMPROVE KERNEL HARDNESS, THE PROJECT WILL MODIFY PRIMARY METABOLISM IN THE ENDOSPERM COMPONENT OF KERNELS, TARGETING STORAGE PROTEIN SYNTHESIS, STARCH SYNTHESIS, AND THE COORDINATED REGULATION OF THOSE TWO PROCESSES.WITHIN PROGRAM AREA PRIORITY A1152, PHYSIOLOGY OF AGRICULTURAL PLANTS, THIS RESEARCH ADDRESSES PRIMARY METABOLISM IN AN AGRICULTURALLY IMPORTANT PLANT, MAIZE (ZEA MAYS), WITH PARTICULAR RELEVANCE TO THE COUPLED TRAITS OF NUTRITIONAL QUALITY OF FOOD AND FEED, AND THE ECONOMICALLY SIGNIFICANT CHARACTER OF KERNEL HARDNESS.