Description, causes and treatment of fusarium potato, control measures
Fusarium is a disease that affects many plants, including potatoes. It also received another name - fusarium wilting or dry rot. Fusarium in potatoes is caused by the action of spore fungi of the species Fusarium oxysporum. According to the description of experts, this disease is especially common in the Far East, as well as in the south and southeast of the Russian Federation. The disease is very dangerous; it is capable of destroying huge areas of potatoes and tomatoes in a short time.
Reasons for the development of fusarium potato
As already noted, the causative agent of the disease is a certain type of fungus. It can be stored for a long time in various conditions: in plant debris, in planting soil or seeds. In these cases, the fungus enters the plant environment through their root system. The fungus begins to develop, which leads to the formation of fusarium. In most cases, the channels of the plants through which nutrients move are simply clogged.
Fungi enter the root system through the roots, damaged during the processing of the soil around the rhizome, by insects (bear or wireworm).
In addition, the infection and development of fusarium can occur for the following reasons:
- the use of inoculum previously infected with the disease;
- before planting, the soil is poorly prepared, no treatment for fusarium has been carried out;
- storage conditions for potatoes were not maintained;
- crop rotation was not maintained, potatoes were planted for several years on the same bed;
- influence of weather conditions;
- invasion of pests;
- lack of mineral and organic fertilizers.
The main symptoms
The period of tying and development of tubers is considered the most dangerous for infection with Fusarium. Plant wilting begins only a month after infection.
The main signs of the disease include:
- rolling of leaves at the top of the bush - this begins at the earliest stage of the disease;
- appearance yellow color on potato leaves, which first droop, and then simply fall off, appears when large areas of the beds are infected;
- the appearance of brown stems, especially in the upper part of the bush;
- stems with high humidity begin to rot;
- the stems are pulled out of the soil without any effort;
- the appearance of a brown core on the inside of the cut stem;
- the presence of dry rot on the tubers during the storage period of potatoes;
- the appearance of gray-brown spots on potato tubers;
- the core of the tubers becomes dry and porous, the peel shrinks, and voids appear in the core;
- on infected tubers in spring, the eyes germinate very slowly, their processes are weak and resemble a thin web.
Preventive procedures
To prevent the disease in order to reduce the risks of infection with fusarium, it is necessary:
- use only healthy planting material;
- choose varieties of planting material only those that are able to resist fusarium;
- choose planting material that is treated by the manufacturer against fungal wilting, such seeds have a distinctive color;
- before laying for storage, as well as before planting, treat the potato tubers with a fungicide;
- strictly follow the rules of crop rotation;
- mercilessly remove infected plants, together with the root soil;
- burn infected plant residues;
- carefully handle garden tools that were used to work with infected plants;
- thoroughly clean shoes from contaminated soil;
- chlorine treatment of all containers that were used for the preparation of planting material;
- thoroughly disinfect the soil, especially greenhouse;
- fertilize the planting soil with potassium oxide or lime.
Preparations for fusarium wilt
Control measures against fusarium wilt of potatoes are divided into two main groups: biological and chemical.
Biological agents
Biological agents are used to protect against diseases during preparation for planting. For this, drugs such as Baktofit, Integral, Fitosporin-M have found applications.
Baktofit
Biktofit is a microbiological preparation designed to combat fungal diseases of various plants, including fusarium of potatoes. It acts directly to suppress the development of Fusarium pathogens - fungi. This drug is not recommended to be mixed with other agents intended to stimulate plant growth, as well as with some fertilizers.
The drug is available in powder or suspension form. For use in small household plots, one package contains from 10 to 12 g of the drug.
The consumption of the drug is determined by the manufacturer's instructions. Usually it is 1 g of the drug per 1 liter of water.
Integral
Integral has been created relatively recently. It contains live bacteria and has a fungicidal effect. It can perform many functions, from protecting plants to accelerating seedlings by 1–2 days. It is also used to disinfect seeds and accelerate growth.
Fitosporin-M
The drug can be used for various purposes, but in most cases it is used for processing vegetables.
Before planting, potato tubers are processed in the following proportion: 3 tablespoons of the preparation for 1 glass (250 g) of water.
In order to prevent or treat diseased potato bushes, it is recommended to spray them at intervals of 1 time in 10-14 days. The concentration of the drug should be: 10 g per 5 l of water. The deciduous mass of potatoes is sprayed.
Chemicals
Chemicals are used to protect potato tubers both during growing and during storage. For these purposes, such drugs as Titus, Maxim, Vist and Kolfugo Super have proven themselves well.
Titus
Titus is a systemic herbicide that can be applied to many plants, including potatoes and tomatoes. Its main purpose is weed control. Already after a few hours after treatment, the growth of weeds stops, and after 15–25 days the weeds die.
To process potatoes, you must prepare a solution of the drug. So, for processing one hundred square meters of potatoes it is necessary to dissolve 0.4-0.5 g of the drug in 2-3 liters of water.
Maxim
The drug is intended for the prevention and treatment of fungal diseases of various plants.On the other hand, it stimulates an increase in their immunity, and also prevents the development of various pests. It is widely used in the process storing potatoes.
This drug has one significant drawback - it does not treat fungal diseases inside the tubers.
To process potatoes, dissolve 4 ml of the drug in 2 liters of water and mix well. To process 1 kg of potatoes, you need to use 1 liter of water.
Whist
This drug is used mainly during the storage period of potatoes. Processing is carried out by fumigation - fumigation of tubers.
The drug is housed in smoke bombs of various sizes. It should be fumigated no later than a week after the potatoes were placed in storage.
Close all doors, gates and other openings in the store before processing. Then light the checkers and ventilate the closed room for at least 3 hours. After processing, the storage in a closed state must stand for at least a day.
Kolfugo Super
The active ingredient of the drug is carbendazim. The drug is intended for the prevention and treatment of plants from various diseases, including fusarium of vegetable crops.
To process potatoes, you need 0.5 liters of the drug per hectare of plants.
Processing scheme
The fight against fusarium potato begins with the preparation of planting material and planting. First of all, it should be remembered that you can only plant potatoes on the old beds after 5 years.
To grow a good and healthy crop, the following pattern should be followed:
- Inspect the seed in good light. Discard tubers suspected of having Fusarium disease, dents, spots, or other skin damage.
- Sprouting tubers. It should be started 25-30 days before planting. For germination, it is recommended to place the tubers in a room with a temperature of + 19–21 ⁰C.
- Select the strongest tubers with pronounced sprouts.
- Treat tubers with any disinfectant solution.
- Potatoes should be planted in pre-prepared soil. Planting depth should be within 10 cm.
- Until the stems close, the potatoes are earthed.
- For the purpose of prevention, when the tops reach about 25-30 cm, it is sprayed with one of the systemic fungicides.
- The next spraying should be done before flowering. To do this, you can use the drugs Epin, Oxygumat or Exiol.
- Then, after 1–2 weeks, the potatoes are treated with contact fungicides. It can be any drug.
- After flowering, the potatoes are treated with the Bravo preparation, and then after 7-10 days, repeated spraying is carried out with the same means.
- At the stage of potato ripening, it is sprayed with Alufit.
- 15–20 days before harvesting, it is recommended to cut the tops and take them out of the garden. Removing the tops promotes the rapid overgrowth of the tuber skin when it is damaged. And this will reduce the risk of disease during storage.
- Harvesting. This procedure should only be performed in dry weather.
- Laying tubers for storage. Storage for this begins to be prepared 2 months before the laying. It must be thoroughly disinfected. Bleach is well suited for this. To prepare a disinfectant mixture, you need 2 kg of lime per 10 liters of water.
What mistakes do gardeners make?
In the process of growing potatoes, gardeners most often make the following mistakes, which contribute to the development of fusarium:
- due to small planting areas, the order of crop rotation is not maintained;
- potato varieties are planted that are not immune to fusarium;
- harvesting is carried out without preliminary cutting of the tops;
- tubers are not examined before planting, and, as a rule, diseased specimens are planted;
- the storage is not disinfected before storage.
If you follow the recommendations presented above, then you can not be afraid of fusarium infection of potatoes.
