**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** THE NARROW GENETIC BASE OF UPLAND COTTON (GOSSYPIUM HIRSUTUM L.) HAMPERS THE LONG-TERM AND SUSTAINABLE ENHANCEMENT OF THE YIELD AND QUALITY OF LINT FIBER, ITS PRIMARY ECONOMIC PRODUCT. WE PROPOSE TO INTRODUCE ESSENTIAL NEW GENETIC VARIATION INTO THE UPLAND COTTON GERMPLASM BY CREATING NEW INTERSPECIFIC GENE COMBINATIONS, ALSO BY TESTING THE EFFICACY OF INTROGRESSED QUANTITATIVE TRAIT LOCI (QTL) ALLELES. SPECIFICALLY, WE WILL USE A CAREFULLY SELECTED SET OF QTL ALLELES INTROGRESSED FROM G. BARBADENSE THAT HAVE PREVIOUSLY BEEN IMPLICATED IN ENHANCING FIBER FINENESS AND ASSESSING THE STABILITY OF GENETIC IMPROVEMENT CONTRIBUTED BY THE INTROGRESSED ALLELES IN TWO ELITE BACKGROUNDS. FURTHER, WE WILL DEVELOP 'BREEDER FRIENDLY' TOOLS AND RESOURCES THAT ENHANCE THE ABILITY TO UTILIZE MARKER ASSISTED SELECTION TO MANIPULATE THESE FIBER QUALITY QTLS FOR A LONG-TERM AND SUSTAINABLE ENHANCEMENT OF FIBER FINENESS IN BREEDING PROGRAMS. THE TEAM OF SCIENTISTS COOPERATING ON THIS PROJECT, WHICH INCLUDE A BREEDER (CHEE) AND A GENOMICIST (PATERSON) WITH COMPLEMENTARY SKILL SETS, WILL WORK CLOSELY WITH AN ENGAGED STAKEHOLDER (KOTHARI) TO UNDERTAKE ACTIVITIES SALIENT TO PRE-BREEDING AND GERMPLASM ENHANCEMENT, AND DEVELOPMENT AND APPLICATION OF TOOLS TO PREDICT PHENOTYPE FROM GENOTYPE TO ACCELERATE BREEDING OF FINISHED CULTIVARS.