"Common bean (Phaseolus vulgaris L.) is an important grain legume that is high in protein, dietary fiber, and micronutrients. Common beans are diverse in seed types and are grown worldwide, especially in Americas, Africa and Asia. However, bean diseases have severely constrained bean production and farmers have experienced significant crop losses especially those with low input small-scale farms in developing countries. Fusarium root rot (FRR) is a commonly recognized soil-borne disease to cause lesion and necrosis on roots of common beans. In the first part of this study, different Fusarium species isolated from infected bean roots were screened for virulence. Variations of virulence among tested isolates and genotypic variation of plant responses were found. A Fusarium brasilense isolate was selected from tested isolates and used in greenhouse phenotyping of a recombinant inbred line (RIL) population of MLB-49-89A x CAL96 for FRR resistance in the second part of this study. QTL mapping was conducted with field and greenhouse generated data. Eight QTL related to FRR resistance for disease severity score, root biomass, and root/shoot biomass reduction were identified. Disease resistance (R) genes were found in/near three of the QTL regions. In the last part of this study, R genes identified through the transcriptome profiles of two navy beans were characterized and 24 of these R genes were found to contain SNPs. A map was created to overlay genomic regions of R genes and QTL for FRR resistance. The results of this study provide useful information that can be applied to the development of FRR resistant common bean cultivars."--Page ii.
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