Proteus mirabilis

Proteus mirabilis is a facultative anaerobic gram-negative bacterium belonging to the Enterobacteriaceae family. In agronomy, this microorganism is primarily considered an opportunistic pathogen capable of causing bacterial soft rots in a wide range of agricultural crops, particularly under conditions of high humidity and poor post-harvest management.

This bacterium typically infects vegetable crops, including potatoes, onions, cabbage, and various root vegetables. The infection frequently enters plant tissues through mechanical injuries, surface cracks, or sites of pest damage, rendering the tissues susceptible to rapid bacterial degradation and tissue collapse.

The primary symptom of the infection is the rapid softening of tissues, accompanied by a foul odor and a change in tissue color to dark or water-soaked patches. Over time, the affected plant parts turn into a viscous, slimy mass, leading to complete loss of marketability and total destruction of the harvest during storage.

The development of Proteus mirabilis is favored by temperatures ranging from 25 to 35 degrees Celsius and excessive moisture in the air or soil. The pathogen spreads rapidly through contaminated tools, containers, irrigation water, and insect vectors that compromise the physical integrity of the plant's epidermis.

Protection measures focus on crop rotation, thorough cleaning and disinfection of storage facilities before harvest storage, and timely pest control to prevent surface injuries. It is critical to maintain optimal storage conditions, such as low temperatures and effective ventilation, which inhibit the rapid proliferation of these bacteria.