Tomato Diseases PDF Print E-mail

Below are some of the common diseases you should be on the lookout for regarding farming tomatoes in tunnels

  1. Powdery Mildew (Oidium):

    • Symptoms: The fruit remains uninfected but small circular shaped areas of a white fungus occurs predominantly on the upper leaf surface. As this grows, the leaf firstly turns yellow before it turns brown and shrivels up.
    • Cures: Sulfur as well as many fungicides can be used to control this disease.
  2. Catface, Cracking:

    • Symptoms: The fruit will be misshaped, often with cracks or lines coming from the base of the fruit. This condition is more common during abnormally cold weather and also aggravated by high nitrogen levels in the soil.
    • Cures: This can be easily managed by proper irrigation, monitoring the temperature as well as managing and monitoring the nutritional levels.
  3. Blossom-End Rot:

    • Symptoms: It starts as a light lesion at the blossom end of the fruit turning into a dark brown sunken lesion. This generally becomes larger and begins to sink more. The first fruits to show symptoms of this disease are generally half developed fruits.
    • Cures: To reduce the chances of this disease, apply lime or calcium based fertilizers before planting. The plants must also get a constant supply of moisture through irrigation. Mulch can also be applied.
  4. Yellow-Leaf Curl:

    • Symptoms: Initially the plant's leaves cup and twist in an upward direction. If the plant is severely affected, it will not bear any fruit. Less severe plants will have signs of the following:

      • Cupping of the leaf
      • Leaves start to turn yellow
    • Cure: Solanaceous weeds need to be removed from the tomato crop. The rate of the spread of disease can be slowed by applying a suitable mineral oil spray regularly to the plant which prevents the white fly of transmitting the disease to the plant.
  5. Early Blight:

    • Symptoms: The symptoms may occur on the stem, leaf or fruit, however it is more common for irregular brown lesions to occur, initially on older leaves. These lesions grow and expand eventually developing into black rings which are often surrounded by a yellow area. If there are many affected areas on the leaf, the leaf turns yellow and dries up.
    • Cure: To control early blight disease a fungicidal spray along with a blight forecasting system is the most effective method.