Bacterial canker, Clavibacter michiganensis, subsp. michiganensis (Cmm), is a vigorous pathogen persisting in contaminated soil and seed and causing significant damage to tomato production worldwide. Protocol optimization aims to determine the best method of Cmm inoculation, and screening for the disease. A recombinant inbred line (RIL) population of tomato, segregating for Cmm resistance, will be used to identify and map genes conferring resistance. The ultimate goal is to develop tomato varieties with resistance to Cmm.