Soybean yield differences are a combination of the genotype, environmental conditions, and management practices. Understanding how these factors interact through the analysis of the components involved in yield determination, provides a way to increase potential and actual yields in Kentucky. Two irrigated experiments were conducted to quantify differences in the mechanisms of yield determination across soybean maturity groups (MG) 2 to 5 (Chapter 1), and to quantify management options (seeding rate and choice of MG cultivar) that increase yield potential of double crop soybean systems (Chapter 2). Results showed that cultivars used different physiological strategies to achieve high yields, but these were not always consistent across the environments studied. High yields were often associated to a higher efficiency partitioning biomass to seeds that lead to a higher seed number in some cultivars, as well as associated to low seed growth rates (Chapter 1). The choice of MG cultivar had a greater impact on double-crop soybean yields than increasing seeding rates from 40 to 54 seed m-2. The higher seeding rate increased yields by 5% without an interaction with cultivar. Optimal MG choices for double-crop soybean in KY were dependent on the environment.