Tomato blossom-end rot

Blossom-end rot is a common physiological disorder affecting tomatoes, peppers, and other solanaceous crops. Unlike bacterial or fungal infections, it is caused by a localized deficiency of calcium within the developing fruit, which prevents cells from building strong walls and leads to tissue collapse.

The primary symptom is a water-soaked, light-colored spot on the blossom end of the fruit. As the fruit grows, the spot enlarges, turns dark brown or black, becomes leathery or sunken, and dries out. While the surface may appear dry, the internal tissue can sometimes rot further due to secondary infection by opportunistic pathogens.

Environmental stress is the main catalyst for this condition. Erratic watering, leading to rapid fluctuations in soil moisture, hinders the plant's ability to transport calcium from the roots to the fruit. High temperatures, excessive transpiration, and high salinity in the soil also exacerbate the condition by limiting nutrient uptake.

Prevention focuses on maintaining a steady supply of moisture to the plants. Consistent watering is essential for the even growth of fruits. If the soil is deficient, adding gypsum or lime before planting can help, while foliar applications of calcium sprays during the early stages of fruit development can provide a quick remedy when soil uptake is hampered.

• Maintain consistent soil moisture levels.
• Apply mulch to stabilize soil temperature and moisture.
• Avoid heavy nitrogen fertilization during fruit set.
• Use calcium-based foliar fertilizers.
• Plant in well-draining, nutrient-rich soil.

The economic impact of blossom-end rot can be severe, often resulting in significant yield losses for both home gardeners and commercial producers. By managing the irrigation strategy and monitoring the nutrient balance, growers can effectively reduce the occurrence of this disorder and ensure the production of healthy, high-quality fruits.