Dickeya lacustris

Dickeya lacustris is a gram-negative plant-pathogenic bacterium belonging to the family Pectobacteriaceae. This organism is recognized as a significant causative agent of soft rot, capable of affecting various crop species and causing substantial post-harvest and field losses.

The primary hosts for this pathogen include potatoes, tomatoes, and other solanaceous crops. The bacteria produce powerful cell-wall degrading enzymes (pectinases) that facilitate the rapid dissolution of plant cell walls, leading to tissue collapse and plant death under favorable conditions.

Common symptoms of an infection include severe wilting, chlorosis, and necrotic lesions on stems and leaves. When tubers or fruit are affected, they develop watery, discolored, and soft lesions. In advanced stages of infection, the infected plant organs turn into a liquid, malodorous mass, rendering the crop unmarketable.

The development and spread of Dickeya lacustris are heavily influenced by environmental factors, particularly warm temperatures and high moisture levels. The pathogen can persist in infested crop residues, soil, and water sources, spreading rapidly during wet seasons or through contaminated equipment during harvesting and handling.

Management strategies focus primarily on exclusion and sanitation, as there are no direct chemical curative treatments for bacterial soft rot. Producers should implement integrated pest management, which includes utilizing pathogen-free certified seeds, optimizing irrigation to prevent waterlogging, controlling insect vectors, and ensuring strict hygiene protocols for all storage facilities and machinery.