The most dangerous tomato disease is bacterial cancer. Rod-shaped bacteria that do not move are the causative agents of this tomato disease. The usual summer average temperature is an excellent medium for the reproduction of these bacteria. Only at a temperature of +50 degrees do bacteria die.
Throughout their development, tomatoes are affected by bacterial cancer. Due to this disease, tomato tissue is mechanically damaged. The first symptoms that tomatoes get bacterial cancer can appear within two to three weeks after the seedlings have been planted in open ground. There are two forms of this disease.
In the first form, the entire vascular system of the plant is affected, from this it withers and completely dies. This is the most dangerous form of bacterial cancer.
The second form is manifested in the fact that the fruits and the whole plant are covered with spots, ulcers grow throughout the plant. If you cut a leaf of tomato infected with bacterial cancer, you can observe a darkening of the vascular system.
This disease is dangerous because bacteria can easily transfer to other plants, although they are not mobile, they get this with the help of wind and rain. Science has proven that on sandy soil these bacteria are much more stable than on soils rich in humus and others. They remain even in the fruits when they are completely decomposed for two to three years.
Even the seeds of bacteria infected with bacterial cancer are a direct source of this dangerous disease. Therefore, to avoid trouble when growing tomatoes, you need to use only proven and high-quality seeds. If there is any doubt, it is better to treat the seeds with a solution of formalin or hydrochloric acid before planting. This procedure will take only ten minutes, but there will be a guarantee that the seeds are healthy. If infection does occur, diseased plants must be urgently destroyed, and the soil completely changed or disinfected.