Despite the significant length (some species up to 2 mm), this filiform, transparent worm cannot be seen with the naked eye. Roots, stems, leaves and flowers are affected.
Infection occurs with planting material. You can purchase an affected leaf or baby. The danger is any soil purchased in the store, garden land. Less likely to be infected through forest land.
By removing a diseased leaf or stepson on the affected plant, and then touching a healthy plant with these hands, you can infect it with nematodes. Parasites enter plant tissue through stomata or wounds.
It is almost impossible to cure a sick plant or disinfect the soil!
An adult nematode lays larvae inside itself, a cyst is formed, with a very stable protective shell. It will be stored for many years in unfavorable conditions, in the absence of moisture, when frozen, even when heated to 100 degrees. Poisons, even the strongest ones, also do not destroy the cyst, but only adults kill. Such poisons cannot be used in indoor conditions, they are dangerous both for the plant itself and for humans.
Signs of a nematode
1. The sheet suspiciously does not give children for a long time. There may be other reasons for this, but this should be alarming. If the kids still hatch, they grow very badly. If you carefully examine the root system of the leaf, you can find bloating galls there. Kids, sheet, earth, dishes - everything must be destroyed and your hands washed.
2. If a young plant is affected by a nematode, then this is expressed in the following:
- the stem extends and thickens;
- growth slows or stops altogether;
- even a very young rosette develops a huge number of tiny stepsons in the axils of the leaves, but they hardly grow;
- petioles of leaves and peduncles shorten, the uppermost leaves are practically devoid of petioles;
- the rosette is squat, the center of the rosette often does not rise, but rather below the extreme leaves;
- a large number of tops are molded one on top of the other;
- leaf blades acquire a dark green color, become hard as if leathery, in the center the leaves are disproportionately small, elongated, sometimes as if pointed to the end, convex, the edges are bent inward, sometimes the tips of the leaf are "needle";
- petioles, veins of the leaf may have swellings, growths, deformity of the leaf, yellowing, then death;
- violet is easily exposed to disease;
- flowers do not form or are obtained ugly, asymmetric, rigid, small;
- wilting of leaves, despite optimal watering - nematodes feed on plant sap, nutrients are consumed for the formation of galls, in addition, vascular blockage occurs, all this complicates sap movement and nutrition, leaves lose turgor;
- violet roots have a characteristic appearance - in healthy senpolia, the roots are fibrous, delicate, thin, diverge in all directions, like tassel hairs; no thickening in the form of a "carrot" or celery root should appear.
When affected by nematodes, the resulting bloats on the roots merge into warty growths 2-3 cm in size - these are the so-called galls, in which the larvae grow and turn into sexually mature individuals. The number of larvae there is terrifyingly huge. There should also be no nodules on the roots, balls that look like beads. The color of healthy roots is light brown, yellowish, the very young tips of the roots are white. When galls appear on the root system, part of the roots dies, they become brown, black.
All this should be taken into account when you bought senpolia and after quarantine for a period of 2-3 weeks you are going to transplant it into a new pot.
Nematode control and prevention measures
- Addition to the substrate of the drug "Fitoverm" in the form of a powder (the active substance aversectin) - the substance does not kill nematodes, but causes their deorynthesis, the pest dies from exhaustion before it has time to find the root, and will invade it. Do not apply phytoverm with irrigation or spraying.
- You can try to add the drug nematocide or dosamet (thiazone) to the soil before planting.
- Apply drugs that strengthen the immunity of the plant, increasing the resistance of the plant to adverse conditions.
- Use drugs related to chitosans that stimulate the development of chitinoparasitic microorganisms in the soil. Presumably, the earth from under the flowers of marigolds contains such microflora, it has been noticed that nematodes are not activated in it. You can water violets with the infusion of these flowers or add dried and ground marigold flowers to the ground.
- Maintain the soil acidity not more than 6.5 pH. Nematodes do not like an acidic environment, peat is poorly tolerated, so it is advisable to add it when composing an earthen substrate. To prevent the soil in the pot from snapping, you can water with peat infused water.
- Wash your hands after work with each individual plant that inspires concern.
- Do not grow children in a common area, it is advisable to plant them after separation from the mother's leaf in a separate container.
- It is better to keep pots with violets on separate pallets, which must be washed very carefully from time to time. Water draining from an infected plant is contagious.
- Create the most favorable conditions for violets, prevent excess humidity, which contributes to the rapid development of nematodes. Provide the necessary batteries. Timely micronutrient feeding reduces the activity of nematodes, biohumus application has a similar effect, therefore, Terra Vita soil based on biohumus is good for preparing a substrate for violets.
- When buying violets, it is advisable that the leaf is cut right before your eyes from a healthy-looking plant. Otherwise, the sheet must be rooted in a separate container on a separate windowsill. Leaves petioles leave a minimum of 1.5-2 cm. There should be no ulceration, swelling, deformities on the petiole and leaf.
- When seating children, carefully consider the roots for the presence of the smallest balls and nodules. During transshipment and transplantation, if the earth feed is destroyed, dead sections of the roots are visible. In a healthy plant, the earthen lump does not fall apart if it is removed from the pot, and white root tips are visible throughout its surface.
- If you find one of the signs of nematode damage, look for other signs. Depending on the species of nematodes, they can be different. With a strong defeat, it is better to get rid of the plant.
- When using used pots, in order to prevent them, they must be carefully treated with some kind of aggressive liquid to remove congestion in the sewer, applying it with a brush so as not to damage your hands. Close the pots with plastic wrap so that the liquid does not dry out, and rinse thoroughly after 15-20 minutes.
Caring for sick violets
If a rare variety of violets turned out to be affected and you want to preserve it at all costs, then the following measures can be proposed:
- find an intact leaf, cut off most of the petiole and try rooting it
- if the top is not damaged, try to cut it off and re-root
- create ideal conditions for the affected plant, change the soil by removing the affected roots, observing preventive measures
The main thing is to try to prevent the invasion from spreading to healthy plants. The carrier of the infection can be flying sucking insects .
The author of the article Rusinova T.A.
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