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Sowing is an experience that is always very satisfying and educational. We can learn a lot from the whole process, from the first day we take a seed and put it in a pot, since there are usually no problems. Now, the ones that are ... they can kill our plants in a matter of days.
Perhaps it has ever happened to you, that you had healthy and growing seedlings, and that suddenly they have started to wither. You haven't seen any signs of plague, so it was almost certainly the damping-off. But what exactly is this? Can it be prevented?
What is damping-off?
Damping-off is an English term that refers to the fungal wilt of seedlings. It is also known as seedling rot or seedling drop. This disease is caused by fungi, mainly by those of the genus Phytophthora, Rizoctonia and Pythium.
The problem with these organisms is that they reproduce so quickly that they kill the plant in a matter of very little time. So sadly the best cure is prevention, since no truly effective fungicides have been found to date that can eliminate them. For this reason, it is important to understand how to prevent this disease and properly care for our plants to avoid their loss, which is related to the proper use of planting techniques and with information about rhizoctonia, which is another related pathogen.
How to prevent it?
Although the seedling mortality rate is very high once the fungus has started to harm it, in reality it is very easy to prevent. To do this, I recommend you follow these tips:
- Use whenever you can new and / or clean substrate and seedbeds.
- Treat the seeds with fungicide (for example, copper or sulfur) before sowing them, and the seedbed once a month with broad-spectrum liquid fungicide for greater effectiveness.
- Put the seedbeds in full sun, unless it is a shade species.
- Evita overwatering, which can encourage fungal growth.
- put a maximum of 2 seeds in each alveolus to avoid overcrowding.
- If there are any seedlings that start to decline, take it off and do a fungus treatment.
In this way, you will surely be able to raise a large number of plants .
Hello Monica !!!
I'm about to stratify coniferous seeds and I'm reading the fateful damping off process.
About your article I would like to ask you some questions.
Before putting the seeds, have to stratify them, do I have to put copper or sulfur fungicide or both?
Do I put them in the water where you have to put the seeds for 24 hours or after taking them out of the water?
The trays that I am going to use are totally new, do I have to spray them with copper, sulfur or both?
The substrate will surely have to be 50/50 peat and sand. Do you have to spray the substrate with the fungicide of copper, sulfur or both?
I take the sand out of the stream near my house and put it in the microwave for 15 minutes at maximum power. Could you do the same with the peat or just apply the copper fungicide, sulfur or both?
Once the seedlings are in their seedbeds and placed in the sun and well ventilated, do we have to continue doing the fungicide treatment of copper, sulfur or both?
Every how many days do you have to repeat the treatment?
Can copper and sulfur be mixed in the same water? For example, copper is 3g per 1 liter of water and sulfur the same, I put in 1 liter of water, 3g of copper and 3g of sulfur? Or would it be to put 3g of copper and 3g of sulfur in 2 liters of water?
I know that there are many questions but there are also many doubts where it is not explained well in the sites that I have consulted.
Thanks in advance
Hi Ricard.
I answer you in parts 🙂:
-Before stratifying them you can give them a bath with sulfur or copper (it is not necessary to mix them, since both have the same anti-fungal properties).
-You can give them that bath in a glass and have them there for 24 hours.
-If the trays are new, it does not matter to do any treatment.
-The substrate is recommended to treat it. All you have to do is sprinkle the surface with sulfur or copper and then spray it with water.
-When they germinate, and during the spring, it is highly recommended to continue treating the substrate with sulfur or copper. In summer, liquid fungicides should be used.
-The treatment is repeated once a week or every 15 days; when you see that there are almost no more.
-If you want to mix them, you can do it by adding 7g of copper and another 7g of sulfur in 1l of water.
A greeting.
From what I understand, I can sulphate the substrate by dusting the copper for slame and pulverizing the water.
For the sand that I get from the torrent, can I bathe it (after having washed it) with copper and leave it there for 24 hours to sterilize it?
As far as I know, conifers are always associated with a fungus in order to live. The microcurl of the roots must have it. If I treat the substrate with fungicide, do you think the roots will be able to micro-crimp?
In the germination instructions that I have, it says nothing about putting fungicide on the seeds. Hence my doubt on the subject.
I don't know if I can put the page I bought the seeds from here.
I'm going to give you the instructions (translated) for the germination of the seeds.
Here it goes:
PINE
(Pinus strobus)
The seeds of the eastern white pine are relatively easy to germinate and grow. The dormancy within the seed is short and easily broken. This is achieved by a short cold stratification period in the refrigerator.
First soak the seeds in water for 24 hours. Completely drain all the water and place the seeds in a zippered freezer bag. Place the seeds in the fridge, it is important that during this period the seeds do not dry out or become flooded, otherwise the pre-treatment will be ineffective.
After about 8 weeks in these conditions the seeds are ready to be sown. In general, seeds will stop germinating unless treated this way, simply sowing untreated seeds in compost at room temperature will not break dormancy and germination can be disappointing.
Fill your chosen container with a good quality general form compost. Suitable containers can be flower pots, seed trays or plug trays, or even makeshift containers with drainage holes.
Firmly firm the compost and sow the seeds on the surface. If you are sowing in plug trays, sow 1 or 2 seeds per cell. Cover the seeds with a couple of millimeters of vermiculite or failing that a thin layer of sifting compost.
Follow with gentle watering and keep them at room temperature. Germination will begin a few weeks after sowing. Seedlings are reasonably robust and problem free and generally grow to a height of 5-12 cm in the first growing season depending on sowing date and cultural techniques. The densely planted seedlings are at risk of fungal diseases such as "DAMPING OFF" caused by the fungi PHYTOPHTHORA, RIZOCTONIA, PYTHIUM, which can cause the rapid loss of many seedlings.
Developing seedlings should be well in the sun, kept well watered, and free of competitive weeds. Growth will accelerate in the second and subsequent years and developing saplings will be relocated as needed, preferably during the dormant season. After perhaps two or three years they are ready to be planted in their permanent position. This species will grow very large, very fast so plant far away from buildings, power lines, etc.
As you can see, it does not put any of the fungicide and it is driving me crazy !!!!
All the best
Hi Ricard.
The sand yes, you can bathe it with copper to eliminate the fungi that it may have.
The substrate is always recommended to treat with fungicide. Although it is true that conifers need to establish a symbiotic relationship with fungi (mycorrhizae) to be able to develop under conditions, when they are grown in pots they must be treated with fungicides since they are seeds, otherwise we will most likely lose them. .
What can be done is to buy mycorrhizae, which begin to be sold in nurseries, and start using them when the seedlings have passed the first 3 months of life, which are the most complicated.
Another option is to use cinnamon, which has anti-fungal properties but is less potent.
A greeting.
Thanks for the information!
I'll tell you how it went.
regards
Good luck!!
Good morning, Dra Monica, I am growing topito pepper crops near Cartagena, Colombia. Due to temperature conditions and other factors, many plants suffered from this disease. I would like to know if it is possible to favor the birth of new roots on the affected area and thus save the plants? Beforehand thank you very much.
Hi Fredy.
First of all, thanks for calling me a doctor but I'm not 🙂.
The damping-off is a terrible disease for the seedlings, all tend to die since the roots, when we realize it, are already very affected.
The best that can be done is to prevent it, doing preventive treatments with fungicide, or if they are plants for human consumption as is the case, sprinkling with sulfur or copper in spring and autumn.
A greeting.
Hi Ms. Monica, after a cordial greeting, I ask, does applying mycorrhizae in solid or liquid have the same effect on plants?
Do you think damping off can be controlled by having a suitable and clean substrate? and controlling the amount of water?
thanks for your reply
romulus solano
Hi Romulo.
The truth is that I have never bought mycorrhizae and I do not know if it has a different effect depending on the mode of application. I think that in liquid it has a faster effect as they are already diluted in water, but I don't know 100%.
Regarding damping-off. If a suitable and clean substrate is used and the risks are also controlled, the risk of its occurrence is minimal, but existent. It is always better to be safe.
A greeting.
Good morning I have several tomato plants that are presented hanging from the stem that I can put to cure them
Hi Patricia.
You can treat them with copper (spring and fall) or fungicide spray (summer).
A greeting.
Hi there! Plants that suffered damping off can survive? In that case, will they have growth problems or something similar?
Hi loneliness.
They do not usually, because they think that the fungus goes from the roots upwards. The trunk falls ill quickly, and since it is such a young plant it usually dies.
That is why it is important to treat with fungicides before the seed even germinates.
A greeting.