Damage by the Sun
When the tomatoes get over-exposed to the sun, it can cause damage to the fruit. Sometimes, because of high temperature, yellow or green-colored shoulders are developed on the fruit. Chlorophyll present in the shoulder area is not easily broken down. As a result, green patches appear in this region, which later become yellow instead of red. The solution to both the problems is to take proper precautionary measures so that the fruits are not exposed to the heat of the sun. Sun scald is one such problem which arises when there is heavy defoliation or pruning of leaves due to infestations of pests, worms etc.
Deficiency of Phosphorus
This can happen even if the soil of the tomato plant has sufficient amount of phosphorus. The reason is that when the surrounding temperature is very cold, the phosphorus present in the soil cannot be absorbed by the plant. Therefore, it is advisable not to plant tomatoes very early in the season. Plastic mulch can be used to increase the warmth of the soil. Usually, this problem is found in the early part of the growing season. It gets rectified as and when the soil temperature rises, and you do not have to add fertilizer to the soil.
Blossom End Rot
The early symptoms of this disease are slight tan and black spots at the blossom end of the tomato. The size of the spot increases and the fruit rots. This can happen if the temperature is a combination of extreme cold and excessive heat at the time of blossom set. Under such circumstances, deficiency of calcium can take place. It also occurs due to irregular supply of water to the plants, or excessive use of nitrogen fertilizers. In order to manage this problem, all the affected fruits should be removed. Watering the plants properly can prevent the problem from getting worse.
Tomato plants get affected by many different types of diseases. Here we have discussed some of the most commonly found diseases:
- Rot in Roots:
This is caused due to fungal infection. You cannot control the fungus that causes root rotting. Usually, these fungi develop if the drainage of the soil is not proper, or due to excess watering. So, this disease can be controlled by taking proper measures for soil improvement and adequate watering of the plants. You should not plant tomatoes or any other species in areas of the garden that have poor water drainage.
- Bacterial Canker:
The most common symptom of this disease is lowering of the leaves that are located in the lower portion of the stem. Brown-colored streaks often develop at the midribs of the leaves, which may later extend to the stem as well. Many other diseases have similar symptoms. So, to identify bacterial canker, a laboratory test is required. Once the disease is detected, the plant should be destroyed. The diseased plant should not be used for composting.
- Early Blight:
This disease affects the fruits, foliage, and stems of the plants. It is caused by a fungus. Usually, the symptoms show up when the weather is hot. Initially, it attacks the old leaves and black spots appear on them. Then, the affected leaves become dead and fall down. As a result, the fruit suffers sun scald. In case of a heavy infestation, even the stems and fruit come under the attack of the fungus. All the infected plants should be removed from the ground as soon as possible. The debris of the diseased plant should also be removed from the ground. There should be enough space between two plants to help in better air circulation. Sulfur or copper sprays will be useful in controlling further infection.