by Eggplants are very delicate plants. They often suffer from attacks by insect pests and damage by various pathogenic fungi and bacteria. Both in open and protected soil, eggplants sometimes begin to wither and turn yellow. Why does this happen?
Of course, eggplants, like other plants, can wilt from lack of moisture. If the soil is dry, the leaves, starting from the top, lose turgor and droop. But as soon as you water the plantings, the plants “come to life” and, after a few hours, look like before.
With tracheomycotic wilts – verticillium and fusarium – the leaves turn yellow, wither, and after watering the turgor is not restored. The plants gradually die. And if the bushes have already formed fruits, they accumulate mycotoxins and become unfit for food.
The causative agents of tracheomycotic wilt are fungi of the genus Verticillium и Fusarium – live in the soil and affect plants, getting into the vascular system through damage to the roots. Very often this happens during picking or when transplanting plants to a permanent place. In addition, fungi can cause the development of root rot in eggplant seedlings.
How to recognize tracheomycotic wilt
With tracheomycotic wilt, the fungal hyphae grow in the plant’s vascular system, clogging it, preventing the flow of water and nutrients, causing poisoning of the plant organism. If we cut the stem, we will see a brown ring of damaged vessels.
Verticillium wilt manifests itself starting with older, lower leaves. First, the edges of the leaf blades turn yellow and curl, interveinal chlorosis appears, and then brown spots form, surrounded by a yellow border. Over time, the leaves dry out and fall off, but new ones can grow in their place, that is, the disease develops gradually, over a long period of time, affecting the vascular system from the bottom up.
With fusarium, not only the lower but also the upper leaves of plants wither and turn yellow, sometimes asymmetrically, necrotic areas appear on the root collar and roots. With high air humidity, the stems at the base can be covered with pink or orange spores of the causative fungus. And if verticillium usually affects individual bushes, then fusarium affects several closely growing plants, or even the entire bed. Therefore, it is important to take action as quickly as possible before the disease spreads.
What to do if eggplants are sick
Unfortunately, there are no effective treatments for plants dying from tracheomycotic wilt. External signs of fusarium and verticillium wilt usually appear when the plant’s vascular system is already affected. However, it is quite possible to suppress the spread of pathogenic fungi in the soil and protect healthy bushes.
First of all, it is necessary to remove diseased plants together with the clod of earth. It is also necessary to carefully remove the mulch around such bushes and the leaves lying on the ground, that is, all plant remains, and then throw them away or burn them (disease bushes cannot be put in the composter). After this, it is necessary to treat the garden tools with an antiseptic (for example, a 1% solution of Oxidez or Sanosil).
Fungi that cause tracheomycotic wilt, in particular fusarium, can penetrate the surface of a plant organ over time from the conducting vessels through undamaged tissues. Therefore, the sooner we remove the affected specimens, the better.
The soil and remaining plants should be watered with a solution of a biopreparation based on hay bacillus or trichoderma: Fitosporin-M, Baktofit, Baktogen, Alirin-B + Gamair, Bakterra, Trichoderma Veride 471, Trichoplant, Sporobacterin. As practice shows, hay bacillus preparations are more successful in dealing with the problem of tracheomycotic wilt during the growing season, since the fungi are able to populate plants, penetrating into the tissues.
On the eve of treatment, prepare a solution according to the instructions, water the plantings, and after 5-7 days, repeat the treatment and feed the remaining plants with a complex fertilizer with microelements (Kristalon Orange, Agricola for tomatoes, peppers, eggplants, Fertika Lux, AgroMaster 3:11:38+4, etc.). The main way to combat tracheomycotic wilt is prevention, and the primary task is to improve the soil.
Prevention of tracheomycotic wilt consists of the following:
- remove all plant debris in the fall and dig up the soil;
- carry out crop rotation, sow green manure plants after harvesting (cereals, cruciferous plants);
- normalize soil acidity, add ash, dolomite flour or chalk as needed;
- prevent the appearance of root rot on plants (monitor the air and soil temperature at the seedling growing stage, do not over-water, add loosening agents to the soil);
- populate the soil with beneficial microorganisms, use biopreparations based on Trichoderma, hay bacillus, pseudomonas;
- treat seeds with fungicides before planting;
- during the growing season, do not apply excessive amounts of nitrogen fertilizers, choose complexes that contain increased amounts of potassium, phosphorus and a full range of microelements;
- prevent the spread of insect pests.
The soil is home to a great variety of different microorganisms. In particular, fungi of the genus Fusarium and Verticillium participate in humus formation and are part of the normal soil biota. And the gardener’s task is not to make the soil sterile, but to maintain the microbiological balance of the soil, and thus the immunity of plants.
