Dampling Off

The gardeners who are growing tomatoes in their vegetable garden have practiced of raising tomato seedlings from the tomato seeds. The gardeners know the fact that some tomato seeds generally fail to germinate after they are sown. The damping off pathogens infect the tomato seeds as the seeds swell in presence of moisture in the tomato seed bed. The tomato seeds become soft and change into brown color. The seeds become invisible due the decomposition caused by the damping off pathogens.

Tomato seeds germinate and emerge above the soil surface in about 8 days after sowing. Just after the tomato seedlings emerge from the soil surface, they die. The affected regions in the roots or crown of the seedlings are pale brown, looks like water-soaked region. The tomato seedlings die as the stems of the tomato seedlings collapsed due to the damping off pathogens. The symptom may vary. In this case the tomato seedlings cannot grow well as result of rot in root or collar. As the result of the damage, the seedlings of the tomato die.

After 8 days of sowing tomato seeds, young tomato seedlings emerge above the soil surface. Damping off pathogen affects root or stem of the tomato seedlings. Because of the damage on root or stem, plants may start wilting. The root rot causes the tomato seedlings like nutrient deficient seedlings. The root rot blocks the movement of soil water and nutrients to the whole tomato seedlings.

Several fungal pathogens are involved in the damping off of the tomato seedlings. Pythium and Phytophthora cause damping off in cool climate and wet soil condition. Some other fungal pathogens are also involved to cause damping off of the seedlings of several plant species including the tomato seedlings. They are Fusarium and Rhizoctonia which attack the tomato seedlings in warm and dry conditions.

To check the attack of damping off pathogen in the tomato seedlings, soils or sowing medium should be sterilized. A practice of treatment of tomato seeds is also done. For it the tomato seeds are dipped in hot water at 500c for 30 minutes. Then the tomato seeds are treated with a fungicide. Pasteurize the soils or seedling raising medium for sowing the tomato seeds. Treat the soils with fungicide drench immediately after you see any symptoms of damping off in the tomato seedlings. What fungicide is required is also an important question. You better take the information from the local agricultural extension worker.

Precautions must be done to raise the seedlings of tomato if you are growing tomatoes for any purpose. Water the seed bed when the bed becomes dry. Water the tomato seedbed in the late morning. When you are transferring the young tomato seedlings from tray, use pots or transplant containers new or treated with household disinfecting chemicals or fungicide. Don’t drench the seedlings with dirty water.

For growing tomatoes, it is general practice that farmers raise the seedlings of the tomato by themselves. If you are sowing tomato seeds in seedbeds, you better chose the locations that are well drainable. Dry and well ventilated seed bed is preferred. You are advised to raise the seedbeds for raising the tomato seedlings.

The gardeners who are growing tomatoes in their vegetable garden must be very careful during the sowing of the tomato seeds. Don’t sow the tomato seeds densely. If you have sterilized seedbeds, be careful not to use contaminated hand tools for handling the health tomato seedlings. Before the gardeners go to the seedbeds, they should wash their hands and the tools. Please don’t use the water from ponds to water the tomato seedlings. It is because the pond water is source of fungal contamination.

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