Morganellaceae

The Morganellaceae family consists of a group of Gram-negative bacteria that are increasingly recognized for their role as phytopathogens in various agricultural systems. These microorganisms possess a high potential for tissue degradation, causing significant damage to a wide variety of crop plants. By producing extracellular enzymes that dissolve the middle lamella of cell walls, they are highly efficient at inducing tissue maceration.

The primary diseases caused by these bacteria are various types of soft rots. The infection targets the parenchyma cells of host plants, leading to a rapid collapse of tissue integrity. Plants affected by these pathogens typically show symptoms such as water-soaked lesions that quickly become soft, mushy, and often emit a foul odor as the tissue disintegrates under the action of bacterial enzymes.

Host crops include a broad range of agricultural produce, especially those with high water content. Common targets are bulbs (onions, garlic), tubers (potatoes), and various vegetables such as tomatoes and leafy greens. The versatility of these bacteria as polyphagous pathogens makes them a constant threat in both the field during the growing season and in storage facilities post-harvest.

Disease development is heavily dependent on environmental conditions, with high humidity and temperatures between 20°C and 30°C creating an optimal environment for bacterial proliferation. Factors like physical damage, poor drainage, or pest infestations provide the entry points required for the bacteria to colonize healthy tissue. Once established, the bacteria can spread rapidly, especially in crowded storage environments.

Management and control strategies rely on an integrated approach to reduce bacterial populations and limit spread. Key practices include maintaining good field hygiene, crop rotation to reduce soil inoculum, and ensuring that crops are harvested under dry conditions to minimize wounding. For storage protection, proper ventilation and climate control are essential to prevent the spread of decay from infected individual units to the rest of the stock.