Bacterial stem necrosis of tomato

Bacterial stem necrosis is a destructive disease affecting vegetable crops, particularly tomatoes, caused by phytopathogenic bacteria. It is essential to clarify that this condition is purely botanical and has no biological link to Treponema pallidum, which is exclusive to animal pathology.

This disease primarily attacks tomato plants in both greenhouse and field conditions. The bacteria infiltrate the plant through natural openings or mechanical wounds, systematically damaging the vascular system and preventing nutrient transport, which ultimately causes the plant to wilt and collapse.

Common symptoms include dark, necrotic lesions on the stem, which may crack or rupture. Internally, the pith of the stem turns brown, becomes soft, and eventually decomposes. Affected plants often exhibit the proliferation of adventitious roots along the stem as an abnormal growth response to the infection.

The development of the disease is highly favored by excessive humidity, poor air circulation in greenhouses, and high temperatures. Pathogens spread rapidly through contaminated irrigation water, dirty pruning tools, and insect vectors that feed on the soft, infected plant tissues.

Integrated pest management strategies are crucial for prevention. These include using disease-free seeds, strict sanitation of greenhouse facilities, disinfecting tools with appropriate agents, and improving plant spacing to increase airflow. Once a plant shows symptoms, immediate removal and destruction are necessary to prevent the spread to adjacent healthy plants.