THIS STANDARD RESEARCH PROPOSAL ADDRESSES MOLECULAR, CELLULAR AND WHOLE-PLANT APPROACHES TO UNDERSTANDING HOW GROWTH AND DEVELOPMENT AFFECT PLANT PRODUCTIVITY. THIS RESEARCH FOCUSES ON RHIZOMES, VEGETATIVE/REPRODUCTIVE STRUCTURES THAT ARE A VALUABLE ASSET IN PRODUCTIVITY OF BIOMASS, FORAGE, AND TURFGRASSES CULTIVATED ON &GT;60 MILLION US ACRES AND LIKELY TO INCREASE. RHIZOMES ALSO ENHANCE 'WEEDINESS' OF UNDESIRABLE PLANTS THAT INFEST MILLIONS OF ACRES, REDUCING CROP PRODUCTIVITY AND HINDERING UTILIZATION OF POTENTIALLY VALUABLE GENES IN BREEDING. INFORMATION ABOUT RHIZOMATOUSNESS FROM BOTANICAL MODELS EXTRAPOLATES WELL. RELATIVES OF SORGHUM, A MODEL FOR RHIZOMATOUSNESS, WILL BE STUDIED. COMPARATIVE AND ASSOCIATION GENETICS WILL CLARIFY THE GENETIC CONTROL OF RHIZOMATOUSNESS FROM SORGHUM HALEPENSE, DISCERN NOVEL QTLS FROM THOSE SHARED WITH S. PROPINQUUM, AND INVESTIGATE CANDIDATE GENES BY SEVERAL APPROACHES. EXPRESSION PROFILING DURING EARLY STAGES OF RHIZOME DEVELOPMENT AND INGENOTYPES WITH DIFFERENT QTLS FOR RHIZOMATOUSNESS WILL REVEAL GENE NETWORKS, FUNCTIONAL GROUPS AND SPECIFIC GENES ASSOCIATED WITH SPECIFIC S. HALEPENSE QTLS FOR ENHANCED RHIZOMATOUSNESS. AT THE INTERSECTION OF POSITIONAL, EXPRESSION, FUNCTIONAL, COMPARATIVE AND ASSOCIATION GENETIC EVIDENCE, A TRACTABLE NUMBER OF CANDIDATE GENES ARE EXPECTED TO BE STRONGLY IMPLICATED IN THE GENETIC AND DEVELOPMENTAL CONTROL OF RHIZOME GROWTH, PERHAPS INITIATING FUNCTIONAL TESTS BY MEANS SUCH AS CRISPR/CAS GENOME EDITING. THESE APPROACHES WILL ALSO PROVIDE NEW INFORMATION ON GENETIC CONTROL OF TILLERING, ANOTHER IMPORTANT DETERMINANT OF PLANT PRODUCTIVITY. FINDINGS ARE EXPECTED TO ADVANCE KNOWLEDGE TOWARD DEVELOPMENT OF NOVEL METHODS TO ENHANCE PRODUCTIVITY OF DESIRABLE PLANTS AND CONTROL UNDESIRABLE ONES, ALSO TRAINING YOUNG SCIENTISTS IN INTEGRATIVE CONTEMPORARY APPROACHES TO ADDRESSING AGRICULTURAL CHALLENGES.