Pseudomonas tomato

A bacterial disease affecting tomato plants

Pseudomonas tomato

Tomato plant affected by Pseudomonas tomato

Pseudomonas tomato is a bacterial pathogen that causes bacterial speck disease in tomato plants. This disease is characterized by small, dark spots on the leaves, stems, and fruit of the plant, which can lead to reduced yield and quality of the tomatoes.

Pathogen

The bacterium responsible for this disease is Pseudomonas syringae pv. tomato. It is a Gram-negative bacterium that is rod-shaped and motile. Pseudomonas syringae pv. tomato is part of the larger Pseudomonas syringae species complex, which includes many pathovars that infect a wide range of plant hosts.

Symptoms

The primary symptoms of bacterial speck include small, dark, water-soaked spots on the leaves, stems, and fruit. These spots are usually surrounded by a yellow halo. On the fruit, the spots can lead to blemishes that reduce the marketability of the tomatoes. In severe cases, the disease can cause defoliation and fruit drop.

Disease Cycle

The bacterium survives in plant debris and can be spread by rain splash, irrigation, and contaminated equipment. It enters the plant through natural openings or wounds. The disease is favored by cool, wet conditions, which promote bacterial growth and spread.

Management

Management of bacterial speck involves a combination of cultural practices and chemical controls. Crop rotation and removal of plant debris can help reduce the inoculum in the field. Resistant varieties of tomatoes can also be used to minimize the impact of the disease. Chemical controls, such as copper-based bactericides, can be applied to reduce bacterial populations, although their effectiveness can be limited.

Related pages

• Tomato
• Pseudomonas syringae
• Plant pathology
• Bacterial diseases of plants