Bacterial spot of pepper and tomato

The causative agent of the disease is the gram-negative, motile, rod-shaped bacterium Xanthomonas euvesicatoria. This pathogen causes bacterial spot in Solanaceae, affecting all aerial parts of the plant throughout the entire growing season, from seedling stage to maturity.

The primary crops susceptible to this infection are bell peppers and tomatoes. The pathogen can survive in crop debris, soil, and seeds, making it a persistent challenge for both greenhouse and open-field production systems if integrated pest management is not implemented.

The characteristic symptoms appear as small, water-soaked spots that eventually turn dark and necrotic, often surrounded by a yellow halo. On fruit, the lesions present as raised, scab-like spots that significantly degrade fruit quality and market value, making them unsuitable for fresh consumption.

Development and spread of the pathogen are favored by high humidity and moderate temperatures ranging from +20°C to +30°C. The bacteria are easily dispersed through rain splash, overhead irrigation, contaminated tools, and infected plant material handled by workers in the field.

The economic impact involves defoliation, stunted growth, and heavy yield losses. To mitigate the spread, it is crucial to use pathogen-free seeds, practice crop rotation, implement strict sanitation in greenhouses, and apply copper-based bactericides at the earliest sign of disease outbreaks.