Black Leg In Seedlings. How To Fight? What To Do? Prevention. Photo

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Black Leg In Seedlings. How To Fight? What To Do? Prevention. Photo
Black Leg In Seedlings. How To Fight? What To Do? Prevention. Photo

Video: Black Leg In Seedlings. How To Fight? What To Do? Prevention. Photo

Video: Black Leg In Seedlings. How To Fight? What To Do? Prevention. Photo
Video: Damping Off In Seedlings - 8 Ways You Can Prevent It 2023, March

The black leg is a real scourge of seedlings, most often it affects seedlings of crops such as tomatoes, bell peppers, eggplants, cucumbers, various types of cabbage, radishes, lettuce, and from flowering plants - petunias and others grown through seedlings. In this article, we will talk about what a black leg is and how you can deal with it, including in the most effective ways, as well as how to prevent its appearance, that is, about preventive measures.

Black leg on tobacco seedlings
Black leg on tobacco seedlings


  • What is black leg seedling?
  • Why does a black leg form and develop?
  • Preventive measures against black leg seedlings
  • Fight against black leg seedlings
  • We fight with a black leg with folk remedies

What is black leg seedling?

Black leg - this is how gardeners who produce seedlings for personal plots or for sale usually call the root rot of the seedling neck. This is a fungal disease, in the end, with active development, it causes lodging of seedlings and their complete death.

You can understand that your seedlings were struck by a black leg if you carefully examine the base of the seedling stalk, there, in the presence of this disease, you can see a change in the color of the tissue, that is, its blackening, and with the active development of this fungal disease - and rotting of the plant tissue as once at the location of the root collar of the seedlings.

Usually, the black leg is most actively manifested from the moment when the sprouts of the hatched seeds just appear above the soil surface and until the moment when seedlings form two or three true leaves.

Why does a black leg form and develop?

There are quite a few reasons for the formation and active development of such a disease as the black leg of seedlings, it may be the soil deliberately infected with the fungus of the black leg; excessively thickened crops, when moisture stagnates for a long time at the base of the seedlings, which, in combination with above-zero temperatures, gives prerequisites for the development of the disease; excessive soil moisture, when moisture simply does not have time to evaporate and be used by plants; lack of fresh air - when the gardener, fearing a draft, does not ventilate the room at all; an excess amount of moisture in the soil, combined with an abundance of heat - these are ideal conditions for the rapid development of black leg seedlings; sharp changes in temperature - when the gardener, on the contrary, is overly keen on airing the room, which sometimes leads to temperature fluctuations of five or more degrees.

If one or more of these conditions take place, then sometimes only seven days are enough from the beginning of the development of the black leg to the complete blackening of the seedling stems and the death of the seedlings. If you take such seedlings in your hands, you can feel with your fingers how the stems are very softened or, conversely, are characterized by increased fragility.

Mushrooms belonging to the genera Olpidium, Pythium, or Rhizoctonia cause the formation of a black leg. All these harmful fungi live in the topsoil and consume dead plant tissue. At high humidity, fungi cease to feed on dead tissues and begin to feed on living tissues, or they can feed on both tissues at the same time. So, it is the root collar of the seedlings that is at risk during this period.

Thickened planting contributes to the development of black leg on seedlings
Thickened planting contributes to the development of black leg on seedlings

Preventive measures against black leg seedlings

To begin with, you always need to purchase high-quality seeds of modern varieties and reliable manufacturers with a written, not stamped date on the seed package. At the same time, try to give preference to the seeds of new varieties, but with a proven reputation, that is, reviews of which are already available, and you can compare one or another variety with a description from the manufacturer. And of course, try to acquire varieties that are either tolerant or immune to this disease.

If you are not sure of the quality of the seed, then before sowing, we strongly recommend holding them for a quarter of an hour in a light pink solution of potassium permanganate, and then rinse in running water. For the prevention and disposal of seeds from the fungus, if it is present on them, soaking the seeds in a solution of the Fitosporin preparation can help. You can soak the seeds for just a quarter of an hour, and then rinse them in running water. Fitosporin can be used as a prevention of the appearance of a black leg and after picking seedlings, a day after picking seedlings, gently process the soil around the seedlings, trying not to fall on the leaves. The main thing during treatments is just to moisten the soil with a solution of the preparation, they cannot "fill" the seedlings.

Always observe the optimum sowing time for your seeds. For a particular variety, for a particular crop, the time of sowing seeds is always indicated on the package. Often, even a region is indicated there with reference to the sowing time, you should not ignore this information.

You should not rush too much with sowing seeds, the room may not be warm enough, it can be snowing outside the window and it can be quite cold, and the cold from the window will only slow down the development of seedlings, make it difficult to evaporate excess moisture and allow the black leg to actively develop on your seedlings.

Provide enough lighting for your plants, depending on which crop you are growing. With a lack of light, the processes of photosynthesis slow down, evaporation of moisture decreases, the immunity of plants decreases, as a result of all this, a black leg appears.

When growing seedlings, try not to use banal wooden boxes and plastic dishes, but peat tablets or peat-humus pots. These rather modern "devices" will allow to avoid the appearance of a black leg or reduce the risk of its appearance several times. In addition, seedlings do not need to be removed from peat-humus cups, for example - they can be planted directly into the soil of the greenhouse or into open ground, without damaging the root system at all. Although such cups cost a little more than plastic containers, they will significantly facilitate your work and keep the roots of the seedlings intact, and you will get an earlier harvest.

It is important to take care of the soil before placing the seeds there. For example, unfamiliar soil in which you have no confidence can be etched. The best option is a banal dark pink solution of potassium permanganate. It is prepared as follows: you need to dissolve three grams of potassium permanganate in a bucket of soft (that is, melt or rain) water. It also helps to disinfect the soil and rid it of the black leg, treatment with drugs such as Radiance, Renaissance or Baikal, that is, with EM drugs, or spill it with boiling water, destroying both bad (unfortunately, good) bacteria and fungi at once.

After the soil has been disinfected in one way or another, let it "breathe" for three days, and then you can start sowing. If the soil is too "greasy" with an abundance of nutrients, it will not be worse if on its surface you sprinkle a layer of river sand, previously washed in three waters, calcined and dried - it will retain excess moisture and prevent the fungus from developing intensively.

In the event that you are completely sure of the quality of the soil, then you can add a good drug to it, which many use to prevent black leg and other infections - Trichodermin. This drug is easy to obtain and it is not expensive.

After sowing, most gardeners cover a common container with seedlings with food or ordinary plastic wrap or glass. So, this can and even should be done: a semblance of a greenhouse is created, however, every day the air in such a greenhouse needs to be ventilated by lifting the film and sprinkling the soil from the spray bottle if it starts to dry out in order to prevent the earthen coma from drying out.

Black-footed roots and stems of seedlings
Black-footed roots and stems of seedlings

Fight against black leg seedlings

If the black leg was noticed late and about a third of the seedlings are already infected with the infection, then the first thing to do is to prevent the spread of the infection, that is, remove the sick and burn them. Ideally, the remaining seedlings should be transplanted into new, clean soil, but if they are very small, then you can process the places where diseased seedlings grew with a pink solution of potassium permanganate.

All other plants without signs of infection must be treated with Fitosporin. At the same time, watering the finished solution is necessary exclusively under the root system of still healthy plants. If the disease has overtaken the seedlings, when the plants have already managed to form a couple of true leaves, then the Fitosporin solution can be used to treat all the plants of the seedlings as a whole, falling on the leaves, and on the stems, and on the ground.

If this drug is not at your disposal, then you can try to use copper-based drugs to combat the black leg, for example, Bordeaux liquid (1% solution is enough), copper oxychloride (1.5% solution), copper sulfate (1% solution). If none of this is available, or the use of these drugs is unacceptable for you, then you can use a weak (crimson) solution of potassium permanganate and spray the soil around healthy seedlings after removing all diseased ones.

In case of severe infection, when the black leg has hit more than half of the seedling plants and there is nowhere to transplant them, and there is nowhere to take fresh soil, you can sprinkle the soil with a mixture of one teaspoon of copper sulfate and one glass of wood ash crushed into dust, or better - soot, this is the norm for square meter of crops.

In the event that the defeat is strong and you have at your disposal both the place and the soil to transplant healthy seedlings there, then it is better to unpack them into separate cups, using exclusively disinfected soil to fill them. You can disinfect the soil using the methods described above, or take the required amount of soil and calcine it in the oven at 100 degrees for a quarter of an hour. But even after that, it is still advisable to shed the soil with Fitosporin or Baktofit. After planting plants in such soil, they, as a rule, do not get sick, but you can overcome a little and a week after their growth in a new place, rearrange the cups in a room with a temperature a couple of degrees below the one where they stood before.

We fight with a black leg with folk remedies

In conclusion, we will give examples of folk remedies for fighting the black leg. In fact, there are a lot of such means of struggle, but we have chosen the most effective ones.

In the first place - dusting the soil with wood ash or wood soot with a layer of just a few millimeters. Gardeners claim that the black leg does not develop on such soil, and the seedlings grow beautifully.

In second place is watering the seedlings with a solution of ordinary baking soda - you only need one teaspoon of soda per glass of water, this volume is enough for a square meter of the seedling box, and you need to water it once a week.

In third place is the soaking of seeds in Epin's solution, while the ampoule is dissolved in a liter of water and the seeds are soaked in it overnight, gardeners claim that such seedlings are not affected by a black leg.

So, it is clear that a black leg can be dealt with both through competent preventive measures, that is, to prevent its appearance at all, and with the help of various means of dealing with it. But do not think that this disease is not worth focusing on. The black leg is very dangerous and if you miss the moment of mass destruction of seedlings, it will be impossible to return the lost days, and the seedlings will only have to be thrown away, so be careful about this disease.

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