Klebsiella bacterial rot

Klebsiella aerogenes is a facultative anaerobic, Gram-negative bacterium recognized in agricultural practice as a causative agent of bacterial soft rot in a wide variety of plant species. The pathogen thrives by secreting potent pectinolytic enzymes that degrade the middle lamella of plant cell walls, leading to the disintegration of tissues.

Under field and greenhouse conditions, this pathogen primarily affects vegetable crops, including potatoes, onions, tomatoes, and cucumbers. It poses a significant threat during the post-harvest period, causing latent infections that manifest rapidly when storage facilities lack proper temperature control and ventilation.

Symptoms of the disease are characterized by tissue softening, where the affected areas become watery and often emit a foul, putrid odor. In advanced stages, the plant structure collapses completely, turning into a slimy, dark mass, which renders the produce entirely unmarketable and leads to significant economic losses for growers.

Optimal conditions for the development and spread of the bacterium include high relative humidity (above 80%) and moderate temperatures. The infection is typically spread through crop residues, infested soil, and contaminated agricultural tools that create wounds on healthy plants, allowing the bacteria to enter the inner tissues.

Effective management strategies rely on rigorous agricultural practices designed to minimize mechanical damage during harvest and storage. Preventive measures include:

• Maintaining optimal storage environments with low humidity and high air circulation.
• Implementing strict crop rotation and removing debris from fields after harvest.
• Sanitizing storage facilities and containers before housing new crops.
• Regularly inspecting and culling infected produce to prevent the spread of decay within batches.