Book excerpt: This Research Topic is dedicated In Memoriam of Dr. Nicola Sante Iacobellis who contributed to the conception of this article collection † This Research Topic collects the selected contributions to the 14th International Conference on Plant Pathogenic Bacteria (14th ICPPB), “The Impact of Plant Pathogenic Bacteria on Global Plant Health”, which was held in Assisi (Italy) from July 3 to 8, 2022. Occurrence of bacterial disease in plant is the result of complex interaction between host, bacterium and environment. The mechanisms by which bacteria cause shifts in the biochemical and physiological processes required for the plant life cycle as well as the mechanisms by which hosts prevent or respond or defend against attack by bacteria are the central themes of this Research Topic.