Soft rots caused by the bacterial pathogens Dickeya and Pectobacterium are destructive diseases of vegetables as well as ornamental plants. These pathogens can also cause blackleg disease on potatoes, which has resulted in significant economic losses in the United States and continues to devastate the potato industry. Very few management options exist to help control these necrotrophic bacterial pathogens. Due to the limited success of current approaches, there is a need for the development of disease resistance cultivars and alternative methods to reduce losses. My thesis research focused on understanding of molecular host-microbe interactions, evaluating bacterial sensitivity to antimicrobial agents, as well as identification of new hosts for soft rot pathogens. First, a global transcriptomic analysis (RNA-sequencing) was conducted to investigate the early interactions between D. dadantii and susceptible or tolerant diploid potato plants, with a goal of identifying factors involved in disease resistance. Tolerant potato plants displayed increased expression of genes involved in production of small naturally occurring compounds. The efficacy of potassium tetraborate tetrahydrate (PTB) on the inhibition of Dickeya and Pectobacterium spp. was evaluated and the underlying genetic mechanisms of spontaneous Pectobacterium spp. PTB insensitive mutants were proposed. Third, a D. dianthicola isolate was identified as causing disease in New Guinea Impatiens (NGI). This was the first report of Dickeya on NGI and highlights potential risks of the spread of this pathogen to crop fields. The studies contribute to the knowledge of Dickeya/Pectobacterium blackleg pathosystem, provide critical information to help in the development of disease management strategies and disease-resistant potatoes, and make available additional genome resources for researchers studying Dickeya and Pectobacterium spp.